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Amombo, Noa Francoise Mystere. "Crystal engineering of selected phenolic acids." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/734.
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Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Chemistry
in the Faculty of Applied Science
at the
CAPE PENINSULA UNIVERSITY OF TECHNOLOGY
2014Crystal engineering based upon acid: base compounds have been studied in this thesis. Selected phenolic acids such as: vanillic acid (VA), phenylacetic acid (PAA), 4-hydroxyphenylacetic acid (HPAA), 3-chloro-4-hydroxyphenylacetic acid (CHPAA), caffeic acid (CFA), p-coumaric acid (pCA), trans-ferulic acid (tFER), 2-phenylpropionic acid (PPA) and 2-phenylbutyric acid (PBA) were the main compounds investigated. These phenolic acids have formed co-crystals/co-crystal hydrates, salts/salt hydrates and hybrid salt-co-crystals with acridine (ACRI), caffeine (CAF), cinchonidine (CIND), isonicotinamide (INM), isonicotinic acid (INA), nicotinamide (NAM), quinidine (QUID), quinine (QUIN), theobromine (THBR), theophylline (THPH) and urea (U). The two racemic compounds 2-phenylpropionic acid (PPA) and 2-phenylbutyric acid (PBA) were used to study chiral discrimination leading to the understanding of separation enantiomers. Compounds were prepared in different solvents (alcohols, ketone and distilled water) to investigate the relationship between solvents used and the crystalline product obtained. (If there is any effect on the crystalline compound obtained by changing the solvent). The structures were elucidated using single crystal X-ray diffraction. Ground products of obtained compounds were characterized by powder X-ray diffraction (PXRD). Thermal analyses like thermogravimetry (TG), differential scanning calorimetry (DSC) and hot stage microscopy (HSM) were used for the determination of thermal character of the new compounds. IR was also performed to characterize the new compounds. Non-isothermal TG was utilised to obtain kinetic parameters for the water and the methanol release in (pCA−)(QUIN+)•pCA•MeOH•H2O. A selective experiment was done in which quinidine and quinine were used to compete between selected phenolic acids (PAA and HPAA). viii The comparison of the crystal structures determined showed that, changing the phenolic acid while using the same co-crystal former has a significant effect on the type of compounds obtained. The obtained crystal structures were either co-crystal/co-crystal hydrates, salts/salt hydrates or hybrid salt-co-crystals which formed network via means of supramolecular interactions.
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Poquet, Laure. "Metabolism and effects of dietary phenolic acids." Thesis, University of Surrey, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504944.
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Ferulic acid is a secondary metabolite usually found as esters in plants and dihydrocaffeic acid results from the microbial metabolism of flavonoids and of caffeic acid, both widely distributed in food. Even though ferulic acid and flavonoids have been proposed to exert several beneficial effects on health, their in vivo activities could partly result from their microbial metabolites and strongly depend on their bioavailability. The absorption and metabolism of phenolic acids were studied in vitro with a model for the colonic epithelium composed of absorptive and mucus secreting cells, ex vivo with everted colonic sacs and liver slices, and in vivo with rats. The photoprotective effect of phenolic acids was tested in vitro on the keratinocytes HaCaT.The ferulic acid permeation was mainly by transcellular diffusion and also by a facilitated transport (S-MCT and MCTI). Intestinal cells conjugated ferulic acid with sulphate or glucuronide and reduced its unsaturated side chain. In rats, intestinal cells were more potent for glucuronidation of dihydrocaffeic acid, whereas the liver favoured sulphation, the methylation being regio-selective.
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Lal, Priya Kumari. "Maternal prenatal consumption of bioflavonoids and phenolic acids and risk of childhood brain cancer." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1080569687.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xvii, 274 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: J. Schwartzbaum, School of Public Health. Includes bibliographical references (p. 171-203).
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Yeung, Shing Joseph. "Role of mycophenolic acid in kidney transplantation." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31981860.
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Sorour, Noha. "Lipase-catalyzed synthesis of phenolic lipids in solvent-free medium using selected edible oils and phenolic acids." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97003.
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The enzymatic synthesis of phenolic lipids (PLs) in solvent-free medium (SFM), by transesterification of flaxseed and fish liver oils with selected phenolic acids was investigated, using Candida antarctica lipase as the biocatalyst. The enzymatic synthesis of phenolic lipids from flaxseed oil was optimized in terms of water activity, agitation speed, enzyme and phenolic acid concentrations. Increasing the water activity of the flaxseed oil reaction mixture from 0.18 to 0.38 resulted in a significant increase in the bioconversion yield from 62 to 77%. The highest enzymatic activity (178 nmol of PLs/g solid enzyme/min) was obtained with the use of 40 mg of solid enzyme (400 PLU)/mL reaction volume at 150 rpm. Under the optimized conditions there was a significant increase in the proportion of linolenic acid (C18:3 n-3), which increased from 57% in the flaxseed oil to 75 and 64% in the produced phenolic mono- and diacylglycerols, respectively. The volumetric productivity (Pv) of the transesterification of flaxseed oil and 3,4-dihydroxyphenyl acetic acid (DHPA) in SFM was increased 11-fold as compared to that in organic solvent medium. On the other hand, a bioconversion yield of 61% was obtained for the transesterification of fish liver oil with dihydrocaffeic acid (DHCA). Optimization of the enzymatic synthesis of phenolic lipids in SFM from fish liver oil was carried out, using response surface methodology (RSM), based on a four-factor-five-level central composite rotatable design (CCRD). The optimal conditions for the enzymatic reaction were obtained at 50.0ºC, 20.9 mM phenolic acid, 51.2 mg of solid enzyme (512 PLU)/mL, 160 rpm agitation speed, water activity of 0.5 and 3.45 mg Silica gel/mL. The bioconversion yield obtained under these optimized conditions was 86.5%, which is very close to the predicted value of 84.5%. Hence, the predicted values showed good validation with the experimental ones. The overall results demonstrated that RSM can be applied effectively to optimize lipase-catalyzed synthesis of phenolic lipids in SFM, from fish liver oil and DHCA. Under the optimized conditions, there was a significant increase in the relative proportions of the two highly desirable essential fatty acids, where (EPA, C20:5 n-3) was increased from 11.5% in the unmodified fish liver oil to 21.2, 20.7, 20.8, 20.1 and 19.8% in dihydrocaffeoylated, 3,4-dihydroxyphenyl acetoylated, caffeoylated, feruloylated and sinapoylated lipids, respectively, whereas (DHA, C22:6 n-3) increased from 12.0% to 21.4, 19.4, 27.5, 22.1 and 22.0%, respectively. Atmospheric pressure chemical ionization-mass spectrophotometry (APCI-MS) analyses confirmed the formation of six 3,4-dihydroxyphenyl acetoylated and six dihydrocaffeoylated lipids from the transesterification of flaxseed and fish liver oils in SFM using DHPA and DHCA, respectively, as substrates. Although the synthesized phenolic lipids demonstrated radical scavenging activity, expressed as IC50 from 1.6 to 3.7-fold higher than that of its corresponding phenolic acid, it was compared to that of α-tocopherol.La biosynthèse des lipides phénoliques sans solvent, par la transésterification de l'huile de graines de lin (HGL) et l'huile de foie de poisson (HFP) en utilisant comme substrats les acides phénoliques, a été étudiée en utilisant la lipase Candida antarctica comme biocatalyseur. L'optimisation de la biosynthèse des lipides phénoliques à partir de l'HGL a été investiguée en considérant l'activité thermodynamique de l'eau, la vitesse d'agitation, la concentration de l'enzyme et l'acide phénolique. Le rendement de la bioconversion a augmenté de 62 à 77% lorsque l'activité thermodynamique de l'eau du mélange réactionnel de l'HGL a augmenté de 0.18 à 0.38. L'activité enzymatique maximale (178 nmol de PLs/g solide enzyme/min) a été obtenue lors de l'utilisation de 40 mg d'enzyme solide (400 PLU/mL de volume réactionnel) à 150 rpm. En utilisant les conditions réactionnelles optimales, la proportion de l'acide linolénique (C18:3 n-3) a augmenté significativement de 57% dans l'HGL à 75 et 64% dans les produit mono- et diacylglycerols phénoliques, respectivement. La production volumétrique (Pv) de la transésterification de l'HGL et de l'acide dihydroxyphényl acétique (ADHP) en milieu non organique a été 11 fois supérieure à celle obtenue dans le milieu organique. Par ailleurs, le rendement de la bioconversion de 61% a été obtenu lors de la transésterification de l'HFP et de l'acide dihydrocafféique (ADHC). L'optimisation de la synthèse enzymatique des lipides phénoliques a été étudiée en utilisant la méthodologie des surfaces de réponse (MSR), basée sur le factorielle quatre à cinq niveaux sur un plan composite centrale rotatif. Les conditions optimales de la réaction enzymatique ont été déterminées comme suit: 50.0ºC, 20.9 mM d'acide phénolique, 51.2 mg d'enzyme solide (512 PLU)/mL, vitesse de l'agitation 160 rpm, 0.5 de l'activité thermodynamique de l'eau et 3.45 mg de gel Silicate/mL. Le rendement de bioconversion maximum obtenu expérimentalement de 86.5% est très proche de la valeur prédite de 84.5%. Ceci démontre une bonne validation du model. Les résultats, en général, démontrent que la MSR peut être appliquée effectivement pour l'optimisation de la biosynthèse des phénols lipidiques en l'absence de solvant à partir de l'HFP et l'ADHC en utilisant la lipase comme biocatalyseur. Dans les conditions optimales, il y a eu une augmentation significative des proportions relatives des deux acides gras essentiels désirés. L'EPA (C20:5 n-3) dans l'HFP modifié a augmenté de 11.5% à 21.2, 20.7, 20.8, 20.1 et 19.8% dans les lipides dihydrocaffeoylates, 3,4-dihydroxyphenyl acetoylates, caffeoylates, feruloylates et sinapoylates, respectivement, alors que (DHA, C22:6 n-3) a augmenté de 12.0% à 21.4, 19.4, 27.5, 22.1 et 22.0%, respectivement. Les analyses de l'ionisation chimique à pression atmosphérique-spectroscopie de masse (APCI-MS) confirment la formation de six 3,4-dihydroxyphényl acetoylates et de six lipides dihydrocaffeoylates, à partir de la transésterification de l'HGL et de l'HFP avec l'ADHP et l'ADHC, respectivement. Les lipides phenoliques synthetisés ont demontré un pouvoir radicalaire, exprimé par le IC50, de 1.6 à 3.7-fois supérieure à celui des acides phénoliques correspondants, mais il était comparable à celui de α-tocophérol.
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Al-Hadhrami, Mohamed N. (Mohamed Nasser). "Degradation of Phenolic Acids by Azotobacter Species Isolated from Sorghum Fields." Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc501189/.
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Sorghum plants excrete phenolic acids which reduce subsequent crop yields. These acids accumulate in field soil by combining with soil and clay particles to form stable complexes which remain until degraded by bacterial metabolism. The amount of phenolic acids in soil samples were obtained by gas chromatography measurements, while Azotobacter populations were obtained by plate counts in 40 sorghum field samples from Denton County, Texas. One can conclude that increasing the Azotobacter population in the soil increased the degradation rate of phenolic acids proportionally. It is proposed that seed inoculation will introduce selected strains of Azotobacter into the soil. The presence of Azotobacter should increase crop size in subsequent plantings.
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Patel, Chirag G. "The pharmacokinetics and pharmacodynamics of mycophenolic acid in kidney transplant recipients /." View online ; access limited to URI, 2006. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/fullcit/3239911.
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Mothapo, Mmaphefo Patricia. "Comparative evaluation of three fundamentally different analytical methods antioxidant activity determination with reference to bush tea (anthrixia phylicoides." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1517.
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Thesis (M.Sc. (Chemistry)) -- University of Limpopo, 2016In this study, antioxidant activity methodologies were evaluated in terms of analytical performances. The total antioxidant activity from Athrixia phylicoides leaves (Bush tea) determined using 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH•) method, cupric ion reducing power (CUPRAC) method and cyclic voltammetry (CV). Folin-Ciocalteu method was used to quantify total phenolic content (TPC) in Athrixia phylicoides leaves. The influence of chemical and physical parameters on the total phenolic content and antioxidant activity determination were investigated. Results from direct sample and crude sample were compared. Antioxidant activity and phenolic content from Athrixia phylicoides leaves were compared with those from commercialised green tea, black tea and rooibos tea using two chosen antioxidant capacity method with acceptable characteristics. Results from the evaluation of the methods demonstrated excellent recoveries (99 to 103%) consistently, good linearity within the calibration concentration range (R2 = 0.997) and repeatable low coefficient of variation < 5% were indicative of good precision except for CV method. The average total antioxidant activity of various extracts of Athrixia phylicoides leaves ranged from 0.039 to 0.122 mg/mL (EC50), 0.031 to 0.233 mg/mL (EC50) and 339 to 429 mV (anodic potential) for DPPH method, CUPRAC method and CV method, respectively. The total antioxidant activity values for each Athrixia phylicoides samples determined by CUPRAC method were higher than the values produced by DPPH and CV methods. The highest antioxidant activities in the DPPH and CUPRAC methods were found in water extracts (direct sample). However, concentrated samples for DPPH method and CV gave a different trend with the methanol extract (crude sample) displaying the highest antioxidant capacity. Increasing the infusion time only increased total antioxidant activity determined by CUPRAC method, whilst DPPH and CV methods had the highest antioxidant activity in the lowest infusion time (3 min). Even though the results are inconclusive with regard to the effect of solid to solvent ratio effect on the total antioxidant activity, 1:150 ratio and 1:100 ratio extracts for both CUPRAC and DPPH methods and for CV gave the highest antioxidant capacities, respectively. The total antioxidant activities in pure antioxidant standards and in the teas were ranked in the following order by both CUPRAC and DPPH methods: Quercetin > catechin > Trolox and Chinese green tea > Joko black tea > Athrixia phylicoides leaves > Laager rooibos tea, respectively. Comparative study showed the necessity of employing more than one method, as each method for the same sample yielded different results. CUPRAC and DPPH methods displayed higher sensitivity and repeatability as compared to the CV method with poor precision.
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Khoddami, Ali. "Phenolic Compounds in Grains of Australian-Grown Sorghums: Quantitative Analyses including Impacts of Malting and Effects on Broiler Nutrition." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14985.
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Grain sorghum (Sorghum bicolor) is one of the most important food and animal feed crops in arid and semi-arid regions of the world. Sorghum grain is rich in starch and contains many functional health-promoting compounds including B-group vitamins, vitamin E and a broad range of phenolics. There is increasing interest internationally to extend the commercial use of sorghum grain as an affordable but nutritious source of animal feed and as a functional food. The utilisation of energy by broiler chickens offered sorghum-based diets seems inadequate due to various factors such as kafirin, phytate and phenolic compounds, which may limit energy utilisation. The increased use of sorghum as a human food might be achieved partly through understanding the effects of various forms of grain processing. Malting is a biotechnological process that involves soaking, germination and kilning of the grain. For sorghum, malting has been identified as an effective process to increase the bioavailability of the macro- and micronutrients for sorghum based-foods but many questions concerning the biochemical effects of malting remain unanswered. There were two primary objectives for the research presented in this thesis: (1) To assess whether the abundance of phenolic compounds of a range of different classes influences energy utilisation in broiler chickens fed sorghum-based diets (Chapter 3), and (2) To evaluate the impact of malting on the abundance of several classes of sorghum phenolics (Chapter 4 to 6). A substantial collection of Australian-grown sorghum grains were analyzed for total phenolics, flavan-4-ols, antioxidant activity (DPPH; 2,2-diphenyl-1-picrylhydrazyl and ABTS; 2,2’-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid)), total flavonoids and total anthocyanins. Separation, identification and quantification of 3-deoxyanthocyanins, flavones, flavanones, as well as free, conjugated and bound phenolic acids, were also performed using high performance liquid chromatography (HPLC) and liquid chromatography coupled with mass spectrometry (LC-MS). Objective (1) was achieved through collaboration with experts in broiler chicken digestive physiology. A pigmented testa was found to be absent in all the Australian-grown sorghum cultivars examined (16 and 8 cultivars for Objectives (1) and (2), respectively), indicating that they were type I sorghums, which (by definition) lack condensed tannin. Analyses and assessments of other polyphenolic compounds, including flavan-4-ols and phenolic acids, appear to show that these have negative influences on broiler growth and meat production. The total phenolic content (TPC), in vitro antioxidant activity (DPPH and ABTS) and level of flavan-4-ols in the Australian sorghum grains ranged from 3.00 to 4.68 mg GAE/g, 8.50 to 14.47 mol TE/g, 18.81 to 33.73 umol TE/g and 0.84 to 7.98 abs/ml/g, respectively, where /g indicates per gram of grain on a dry matter basis in each case, as used for all experiments reported in this thesis. The total anthocyanin and total flavonoid level ranged from 1.30 to 11.55 abs/ml/g and 0.65 to 1.80 mg CE/g among the Australian sorghums tested. Levels of 3-deoxyanthocyanin ranged from 10.07 to 63.80 μg/g. The flavones detected in sorghum grain were apigenin (pale yellow) and luteolin (yellow). The flavone level ranged from 5.76 to 17.55 μg/g. The total content of flavanones (eriodictyol and naringenin) ranged from 29.39 to 189.62 μg/g, of which the eriodictyol content varied from 28.1 to 55.5% of total flavanones. Naringenin represented all of the flavanone content in one of the cultivars tested (cv. Block). Ferulic, caffeic, p-coumaric, syringic, vanillic, p-hydroxybenzoic and sinapic acids were detected in the grains of all sorghum cultivars tested. The total abundance of free phenolic acids ranged from 9.20 to 38.55 g/g. The most abundant of the free phenolic acids was caffeic acid, which varied from 1.47 to 18.35 g/g. Levels of total soluble conjugated phenolic acids in the sorghum grains varied from 44.50 to 96.76 g/g. Bound phenolic acids were the most abundant form of phenolic acids, with 228.57 to 580.33 g/g. Ferulic and p-coumaric acids were the predominant conjugated and bound phenolic acids among all the sorghum cultivars examined. In determining the effects of malting (soaking, germination and kilning) on the abundance of the grain phenolic compounds, eight different sorghum hybrids harvested from three different regions in eastern Australia in 2011 were analyzed. All the sorghum grains were tannin free based on both a bleach test and a vanillin-HCl assay. Malting decreased the total phenolic content and in vitro antioxidant activity in all samples. The grand means for total phenolics among all the sorghum cultivars were 2.77 and 2.48 mg GAE/g for raw and malted grain, respectively. For flavan-4-ols, the grand means for raw and malted sorghum grains were 2.98 and 2.23 abs/ml/g, respectively. On average, malting reduced the content of flavan-4-ols by 25%. Total anthocyanin levels more than doubled upon malting the sorghum whereas the total flavonoid level decreased by 12%. Luteolinidin, apigeninidin, 5-methoxy-luteolinidin and 7-methoxy-apigeninidin, which were detected as major 3-deoxyanthocyanins in all raw sorghum grains, were all found to increase in abundance upon malting. The content of luteolinindin and apigeninidin increased dramatically from 4.28 to 43.93 μg/g and from 4.43 to 37.89 μg/g, respectively. Overall, the level of flavones (apigenin and luteolin) increased by 68% after sorghum malting, whereas the level of flavanones decreased by 50%. The grand means for total free phenolic acids in raw and malted grains among the eight sorghum cultivars were 29.65 and 22.33 g/g, respectively. Reflecting the result for the distinct set of cultivars analysed above, caffeic acid was the most abundant free phenolic acid. The grand means for conjugated phenolic acids in the raw and malted sorghums were 74.88 and 73.46 g/g, respectively. While these values are very similar, malting did significantly affect the abundance of all conjugated individual phenolic acids. The grand means for bound phenolic acids in the raw and malted sorghums were 391.81 and 378.06 g/g, respectively. There was statistically significant change upon malting in the abundance of ferulic acid as major bound phenolic acid (344.71 and 333.02 g/g in raw and malted grain, respectively). The data obtained in this study on phenolic compounds in sorghum grain should be valuable for sorghum breeders in the selection of lines for specific end uses, food scientists developing sorghum-based products, broiler meat producers, and in the nutraceutical industry.
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Yeung, Shing Joseph, and 楊誠. "Role of mycophenolic acid in kidney transplantation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31981860.
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Williams, Jeffrey Douglas. "The flavonoids and phenolic acids of the genus Silphium and their chemosystematic and medicinal value." Thesis, View online, 2006. http://www.lib.utexas.edu/etd/d/2006/williamsj92964/williamsj92964.pdf#page=3.
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Thesis (Ph. D.)--University of Texas at Austin, 2006.Includes bibliographical references (p. 188-194). Also available via the World Wide Web: http://www.lib.utexas.edu/etd/d/2006/williamsj92964/williamsj92964.pdf#page=3
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Magnoumba, Legnanga Magalli Marcelline. "The trapping of methylglyoxal by phenolic acids : effect on antioxidant and antibacterial activity." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/65835.
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Methylglyoxal (MGO) is a reactive carbonyl species found in Manuka honey reported to cause advanced glycation end products (AGE) formation. AGE’s increase the risk for hyperglycaemia resulting in neuropathy, arteriosclerosis, retinopathy and Alzheimer’s disease. Phenolic acids such as pyrogallol (PY) are known to trap MGO, lessening the harmful effects of MGO as an AGE precursor. However, MGO is also a very effective antibacterial agent therefore; its trapping could have negative side effects. Manuka honey contains both phenolic acids such as gallic acid (GA), caffeic acid (CA) as well as MGO and it is unknown whether trapping of MGO by phenolic acids reduces the antioxidant activity of phenolic acids or the antibacterial activity of MGO. Phenolic acids PY, GA and CA were combined with MGO in a 1:1 and 1:2 ratio. The trapping of MGO with polyphenolic acids was determined with Liquid chromatography-mass spectrometry (LCMS). Total polyphenolic acids (TPC) was determined with the TPC assay. Antioxidant activity was determined with 2,2-diphenyl-2-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC) and Oxygen Radical Absorbance Capacity (ORAC) assays. The effect on cell number and viability was determined with crystal violet and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays on Caco-2 and SC-1 cells. Cellular antioxidant activity was determined with Dichlorodihydrofluorescein diacetate assay. Lastly, antibacterial activity was determined with the turbidity assay on Gram positive B. subtilis and Gram negative E. coli and the ultrastructural morphology of B. subtilis was further investigated with scanning electron microscopy. PY was the only phenolic acid used with trapping ability, forming mono- and di- adducts with MGO reported with the LCMS results, resulting in a decrease in TPC and antioxidant activity measured with the DPPH assay. GA did not show any alteration when combined with MGO at 1:1 and 1:2 ratio in all antioxidant content and activity assays. The antioxidant content of CA in combination with MGO was decreased, although its antioxidant activity (DPPH) was increased at 1:2 ratio. The antioxidant activity measured with the ORAC assay was increased with PY and CA combined with MGO. TEAC assay did not show any changes when phenolic acids were combined with MGO a 1:1 and 1:2 ratio. The cytotoxicity of phenolic acids combined with MGO did not cause a change in cell number or viability of SC-1 and Caco-2 cells. MGO and phenolic acids alone and in combination did no cause oxidative damage (without 2,2'-Azobis(2- amidinopropane) dihydrochloride (AAPH). All phenolic acids in combination with MGO retained the ability to reduce AAPH induced oxidative damage. The polyphenolic acids showed minor inhibition of the growth of B. subtilis and E. coli. PY only reduced the antibacterial activity of MGO at a 1:1 combination of B. subtilis. GA and CA did not alter the antibacterial activity of MGO when combined at 1:1 or 1:2 ratio. This study showed that phenolic acids with the ability to trap MGO can be altered by the mono- and di-MGO adduct formation, altering its antioxidant activity and can further alter the antibacterial activity of MGO.Dissertation (MSc)--University of Pretoria, 2017.
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Kerimi, Asimina. "Exploring mechanisms of action of flavonoids and phenolic acids on pathways of lipid metabolism." Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.578663.
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Epidemiological studies- indicate an association between the consumption of a 'diet rich in polyphenols and several health benefits. As diabetes and other lipid associated diseases are now reaching menacing proportions worldwide, the need for the development of cost-efficient prevention strategies effective at the population level becomes more essential than ever. Studies in the biological effects of polyphenols are now starting to include their hypoglycaemic and hypolipidemic properties and to investigate potential mechanisms through which they may exert their actions. The focus of the present study was to examine the action of various flavonoids and phenolic acids in pathways of energy metabolism and how they may affect the gene expression of critical enzymes involved in lipid and glucose metabolism. Studied flavonols (quercetin, kaempferol, galangin), and coffee phenolic acids and their metabolites (caffeic acid, dihydroferulic acid, protocatechuic acid) were identified as novel regulators of CPTIA, while quercetin was found to importantly upregulate CPTIA & PDK4 gene expression, to restrict glucose uptake and citrate synthase activity, and therefore was shown to potentially modulate energy metabolism in HepG2 cells. Dihydroferulic acid, the main microbial metabolite of chlorogenic acids from coffee was found to significantly increase PDK4 mRNA levels and enhance citrate synthase activity while it increased glucose uptake. On the other hand, a mixture of flavonols at in vivo relevant concentrations was able to produce a synergistic upregulating effect on CPTIA & PDK4, similar to that observed with quercetin, but an increase in glucose uptake. Further studies showed that the induction of CPTIA and PDK4 by quercetin was mediated by more than one transcription factors, with AMPK to have a pivotal role but Nrf2 driven antioxidant mechanisms not to be involved. From our data we hypothesised for quercetin that it sets the cell under a similar with mild starvation state as in between meals. Phenolic acids were further studied for their role in p-oxidation processes and it was demonstrated for the first time that they may form intermediates of p-oxidation as part of their metabolism in HepG2 cells. Our data suggest a novel but distinct role between flavonols and phenolic acids in lipid metabolism. Their action is defined both by direct interactions with enzymes involved in p-oxidation as well as by indirect actions on the transcriptional level. The biological importance of these findings requires further studies with additional models, which will expand our knowledge with regards to the role of polyphenols in lipid metabolism and any possible beneficial in vivo effects. III
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De, Paula Rosanna. "Effect of pasta processing on physicochemical properties of barley β-glucan and phenolic acids." Doctoral thesis, Università degli studi del Molise, 2014. http://hdl.handle.net/11695/66244.
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Il crescente interesse nella correlazione tra alimentazione e salute ha indotto la comunità scientifica ad un maggior impegno nel campo della ricerca di alcune sostanze dalle ri-conosciute proprietà salutistiche (phytochemicals), naturalmente presenti in una vasta gamma di prodotti di interesse agro-alimentare.
I cereali in genere, nonché i prodotti da essi derivati, sono tra gli alimenti più idonei a veicolare composti bioattivi (phytochemicals) come ad esempio β-glucani e composti fenolici. Evidenze scientifiche hanno dimostrato, infatti, che β-glucani e acidi fenolici possono avere importanti effetti fisiologici. Tuttavia, diversi studi riportano che il pro-cesso produttivo può influenzare positivamente o negativamente la componente bioatti-va, determinando pertanto cambiamenti nelle proprietà fisiologiche del prodotto finito.
Alla luce di queste considerazioni, l’attività di ricerca di dottorato ha avuto come prin-cipale finalità la produzione di pasta funzionale a base d’orzo ricca in β-glucani ed è sta-ta sviluppata in tre sezioni:
valutazione delle proprietà chimiche, molecolari e reologiche di sfarinati di orzo waxy in miscela e non con semola di frumento duro;
studio dell’impatto dei processi tecnologici sulla concentrazione e caratte-ristiche molecolari e di solubilità dei β-glucani in paste funzionali;
valutazione della capacità antiossidante e degli acidi fenolici delle paste a base d’orzo waxy prodotte nell’ambito della sperimentazione.
I risultati ottenuti consentono di affermare che il processo di pastificazione può influen-zare la componente bioattiva, in particolare β-glucani e acidi fenolici, presente nel pro-dotto finito. La presente attività di dottorato vuole fornire un contributo al mondo della ricerca e dell’industria, nonché fornire informazioni per la realizzazione di cibi funzionali a base d’orzo.The increasing interest in the relationship between health and nutrition has steered the scientific research towards studying the role of specific food components/ingredients (phytochemicals), which are naturally included in many foods, in the treatment and/or prevention of ailments. Cereals are generally suitable vehicles of bioactive substances (phytochemicals) such as β-glucan and phenolic compounds. Indeed, available literature report that β-glucan and phenolic compounds have a beneficial role in diet and health. However, the literature seems to show that processing of grains, such as pasta processing, may affect bioactive compounds, increasing or decreasing the health-enhancing properties of cereals pro-ducts. Based on these remarks, the current PhD research work aims at developing barley pasta rich in β-glucan as a functional food with the use of waxy barley as a rich source of so-luble dietary fiber, such as β-glucan, and phenolic acids. The research work includes three studies: in the 1st study chemical, molecular and rheological properties of waxy barley individually and in blend with semolina was investigated; in the 2nd study impact of processing (extrusion, drying and cooking) on the concentration and physicochemical properties of the flours and blends, and mo-lecular characterization of β-glucan, as well as viscosity of the developed pasta products was evaluated; in the 3th part of the research antioxidant properties and phenolic acid composi-tion of the developed pasta products was studied. The obtained results show that pasta processing may affect β-glucan and phenolic acids. This research would make a great contribution to the barley research and assist barley industry in the development of innovative functional foods.
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Skoglund, Maria. "Phenolic compounds in oats : effects of steeping, germination and related enzymes /." Uppsala : Dept. of Food Science, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200802.pdf.
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Bergvinson, David. "Role of phenolic acids in maize resistance to the European corn borer, Ostrinia nubilalis (Huebner)." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/7690.
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Host plant resistance of maize, Zea mays L., to the European corn borer (ECB), Ostrinia nubilalis Hubner, has been largely attributed to the hydroxamic acid DIMBOA. However, DIMBOA does not consistently account for observed resistance in both field and greenhouse environments. It was hypothesized that phenolic acids, a major secondary metabolite in plants, make an important contribution to resistance, through cell wall carbohydrate complexes. Preliminary studies incorporating ferulic acid into the meridic diet of the ECB did not show any adverse effects until 10 mg/g, a dosage that is approximately 30 times that found in maize. Semi-preparative samples of sugar conjugates of ferulic and p-coumaric acids were tested using leaf-feeding bioassays that showed phagostimulant activity at ecologically relevant dosages. These observations suggested that soluble phenolics did not make a major contribution to host plant resistance but may be used for host plant recognition by the ECB. Bound phenolics can form dimers with adjacent phenolic acids. It was hypothesized that these dimers, cross-linked phenolic acid-carbohydrate complexes, could constitute a quantitative defence against the ECB. Developmental studies of a resistant maize synthetic using leaf bioassays and standard phytochemical procedures showed ECB larvae prefer to feed on immature tissue within the whorl and on plants between the 3- and 7-leaf stages of development. These preferred tissues had elevated levels of DIMBOA and lower levels of cell wall phenolics and lower levels of detergent fibre than more mature leaf tissue. Leaf toughness related inversely to leaf consumption. Microspectrophotometer readings of abaxial, epidermal cell walls best predicted insect preference for leaf tissues of different maturity. These studies showed that leaf toughness, vis a vis phenolic acid-carbohydrate complexes, is one of the major resistance factors which can account for larval feeding behavior. Environmental factors also influence maize resistance, with light quality having a significant impact. Under reduced UV light conditions, maize resistance in both greenhouse and field environments was reduced as were the levels of cell wall bound cyclobutane dimers. Cyclobutane dimers appear to increase the mechanical strength of leaf tissue by cross-linking hemicelluloses. The changes in maize phytochemistry and nutritional quality that accompanied increased resistance were monitored for leaf(mature and immature), sheath, stalk, node and pith tissues. DIMBOA levels increased with selection as did fibre content and the cell wall phenolics p-coumaric acid and dehydrodiferulic acid. Cultivars developed at the International Center for Maize and Wheat Improvement have resistance to several lepidopteran borer species but the mechanism of this resistance is unknown. Correlations of field resistance were highest for fibre, dehydrodiferulic acid content and protein content. A nutritional model for host plant resistance in maize based on these three plant components was proposed that accounts for 78 to 87 percent of the variation in field damage ratings observed over two years. According to Feeny's hypothesis of plant apparency, maize appears to rely heavily on quantitative defences. This is logical given the extensive areas planted in maize, with many areas employing no-till practices and continuous cropping which elevate the apparency of maize to insect pests. Phenolic acid-carbohydrate complexes have been demonstrated in this study to be a major component in this defence strategy. (Abstract shortened by UMI.)
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Zhang, Chenzhu, and 张辰珠. "The effects of rapamycin and mycophenolic acid on inflammatory and fibrotic processes in the pathogenesis of lupus nephritis: animal and in vitro studies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45898935.
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Gillard, Conrad. "A novel process for the recovery of phenolic compounds from olive mill wastewater." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15964.
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Requirements for the treatment of wastewater have grown increasingly stringent in recent years, while industrial processes face increasing competition. As a result, there is a great demand for the development of processes that not only treat wastewater, but convert it into value added products. In this thesis, a new process of this nature is proposed. Specifically, a two-stage process is conceived to treat olive mill wastewater (OMW), and produce a concentrated stream of phenolic compounds. The primary pollutants found in OMW are phenolic acids and other phenolic compounds. These pollutants adversely affect plant, animal and human life. At present, no method to recover these valuable phenolic compounds from OMW is practiced on an industrial scale. In the first stage of the proposed process, the wastewater stream is heated and pressurised to near critical conditions. Under these conditions, a decarboxylation reaction occurs, converting phenolic acids into non-acidic phenolic compounds. In the second stage, the resulting phenolic products are separated from the aqueous stream, using a heat resistant polydimethylsiloxane membrane. This separation method is capable of producing a permeate with a concentration several orders of magnitude higher than that of the retentate. This thesis aims to generate the fundamental knowledge necessary for the design of each stage of this process.
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Johnsson, Pernilla. "Phenolic compounds in flaxseed : chromatographic and spectroscopic analyses of glucosidic conjugates /." Uppsala : Institutionen för livsmedelsvetenskap, Sveriges lantbruksuniv, 2004. http://epsilon.slu.se/9717372.pdf.
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fadhil, ali abd al-karim alkarim. "Reversed-phase and surfactant modified reversed-phase high and ultra-high performance liquid chromatography of phenolic and aliphatic carboxylic acids." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1574428923192499.
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Morton, Lincoln William. "The role of dietary phenolic compounds in the detoxification of reactive nitrogen species." University of Western Australia. Dept. of Medicine, 2003. http://theses.library.uwa.edu.au/adt-WU2003.0026.
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[Truncated abstract. Please see the pdf format for the complete text.] Interest in the role of peroxynitrite in the pathogenesis of atherosclerosis has increased due to many in vitro studies which have demonstrated its potent oxidising and nitrating capability and immunohistochemical staining studies which demonstrate nitration of tyrosine in vivo. It is frequently suggested that the production of nitric oxide and superoxide at sites of inflammation implicates peroxynitrite as the major damaging reactive nitrogen species in vivo. Evidence for a role for peroxynitrite is often demonstrated by measurement of 3-nitrotyrosine yet even this cannot distinguish peroxynitrite from other nitrating species. Clearly, however, if peroxynitrite is important in atherogenesis, then identification of mechanisms for its detoxification could provide a means of preventing such effects. Therefore, this Thesis has sought to determine whether phenolic compounds of dietary origin can be preferentially nitrated by reactive nitrogen species thereby protecting endogenous structures, such as low density lipoproteins, from atherogenic modifications. This Thesis focuses upon phenolic acids as they have received relatively less attention than other classes of phenolic compounds, such as flavonoids, yet they are quite abundant in socially important beverages such as red wine. In order to complete the required analyses, the development of methods to detect phenolic acids and their nitration products together with 3-nitrotyrosine, dityrosine and 5-nitro-γ-tocopherol was necessary. The initial in vitro experiments described herein sought to determine the products of reaction of peroxynitrite with phenolic acids of the 4-hydroxy and 3,4-dihydroxy type and then to examine whether these products could account for a protective effect upon tyrosine, lipids and endogenous anti-oxidants, if any was observed, when isolated LDL was treated with SIN-1, which releases peroxynitrite through the simultaneous generation of nitric oxide and superoxide. A concurrent minor focus was to examine the relationship between structure and activity of these phenolic acids under various regimes of oxidative insult. These experiments indicate that, at least in this in vitro model, oxidation is a dominant mechanism over nitration. Peroxynitrite was shown to nitrate coumaric acid in moderate yields but exclusive oxidation of caffeic acid appeared to occur. Although a potential role for γ-tocopherol as an anti-nitration agent was inferred, all types of chemical treatment of LDL in the presence of phenolic acids yielded oxidation as the primary end point. In fact, nitration of tyrosine was not detected and nitration of coumaric acid was at the limit of detection. Since nitration of tyrosine is generally regarded as important in many disease states, a more physiological nitrating mechanism involving artificially stimulated neutrophils was used. This system demonstrated that although physiologically relevant reactive nitrogen species can result in nitration of phenolic compounds, in a complex system including biological structures (LDL) and phenolic compounds, oxidation but not nitration of all species appears to occur. As a consequence of the results above, an examination of carotid plaque was undertaken to determine to what extent nitration occurred relative to oxidation in atherosclerotic tissue. These studies applied methods developed herein to detect 3-nitrotyrosine and dityrosine in complex biological matrices as markers of nitration and oxidation respectively. The data obtained demonstrated that nitration was a minor modification of protein (0.01%) compared to oxidation (0.3%) even in a highly diseased tissue such as carotid artery plaque. A secondary study examining plasma revealed that dityrosine, which has been implicated in irreversible albumin aggregation in chronic renal failure and more recently in heart disease, is elevated in chronic renal failure subjects compared to well matched controls. A separate examination of plasma from healthy subjects revealed that in both the fasting and post prandial state 3-nitrotyrosine could not be detected and, in fact, interfering species could be problematic in the GC-MS analysis of 3-nitrotyrosine. The lack of nitration of any substrate observed in vitro using reactive nitrogen species generated in the aqueous phase, the relative lack of nitration of tyrosine in plaque proteins and the lipophilicity of nitric oxide, the precursor of all reactive nitrogen species, suggested that nitration could be more closely associated with lipid structures. The known ability of γ-tocopherol to form 5-nitro-γ-tocopherol was used to probe this concept. The 5-nitro-γ-tocopherol content of lipid extracts obtained from carotid artery plaques was very high (30%). This indicated that nitration is predominantly a lipid phase phenomenon and that nitrating species are present in much greater abundance than oxidising species in vivo.
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Paracatu, Luana Chiquetto [UNESP]. "Ácido cafeico e seus ésteres: inibição do burst oxidativo de neutrófilos e efeito anti-Helicobacter pylori." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/93126.
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Universidade Estadual Paulista (UNESP)
A ação patogênica do Helicobacter pylori envolve a colonização do trato gastrointestinal e a produção de EROs por neutrófilos atraídos e ativados pelo agente da infecção. A reação mediada pelos PMN é, todavia, ineficaz para eliminar o H. pylori e as EROs contribuem para a lesão tecidual e desenvolvimento de gastrites e úlcera péptica. O ácido cafeico é um dos mais importantes compostos fenólicos, e apresenta diferentes propriedades biológicas, entre elas antioxidante e antimicrobiana. O objetivo deste estudo foi avaliar a atividade antioxidante e anti-H.pylori do ácido cafeico e seus ésteres. Foram avaliados os ésteres: cafelato de metila, cafelato de butila e cafelato de heptila e realizada uma comparação entre as propriedades antioxidantes do ácido cafeico e tais ésteres, por meio de ensaio de quimiluminescência dependente de luminol e lucigenina, ensaio de inibição da produção do ácido hipocloroso e também ensaios morfológicos com e sem a presença de NBT. Os resultados deste estudo mostraram que os ésteres do ácido cafeico apresentaram melhores resultados em comparação com o ácido cafeico para a capacidade antioxidante. O cafelato de heptila apresentou os melhores resultados para a quimiluminescência dependente de luminol e lucigenina induzida por H. pylori e/ou zymozan opsonizado na concentração de 10 µM e 1 µM . O efeito do ácido cafeico e seus ésteres, também foi estudado na inibição da produção de ácido hipocloroso por neutrófilos ativados com PMA. O cafelato de heptila novamente provou ser melhor em capacidade antioxidante, levando a crer que a lipofilicidade deste composto...
The pathogenic action of Helicobacter pylori involves the colonization of the gastrointestinal tract and ROS production by neutrophils attracted and activated by the agent of infection. However, the reaction mediated PMN is ineffective to remove the H. pylori and ROS contribute to tissue damage and development of gastritis and peptic ulcer. Caffeic acid is one of most important phenolic compounds, and has different biological properties including antioxidant and antimicrobial activities. The aim of this study was to evaluate the antioxidant and anti-Helicobacter pylori activity of caffeic acid and esters. Esters evaluated: methyl caffeic acid ester, butyl caffeic acid ester and heptyl caffeic acid ester and a comparison between the antioxidant properties of caffeic acid and these esters through luminol and lucigenin chemiluminescence assay dependent, inhibition of production of hypochlorous acid assay, morphological tests with and without the presence of NBT. The results of this study showed that the esters of caffeic acid had better results in comparison with caffeic acid to their antioxidant capacity. The heptyl caffeic acid ester showed the best results for the luminol and lucigenin dependent chemiluminescence induced by H. pylori and / or opsonized zymozan in the concentrations of 10 µM and 1 µM. The effect of caffeic acid and esters, was also studied in inhibiting of production of hypochlorous acid by neutrophils activated with PMA. The heptyl caffeic acid ester again proved to be better at antioxidant activity, implying that... (Complete abstract click electronic access below)
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Talag, Agela Hussain Mohammed. "Phytochemical investigation and biological activities of Sanicula europaea and Teucrium davaeanum : isolation and identification of some constituents of Sanicula europaea and Teucrium davaeanum and evaluation of the antioxidant activity of ethanolic extracts of both plants and cytotoxic activity of some isolated compounds." Thesis, University of Bradford, 2016. http://hdl.handle.net/10454/14482.
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The aim of this research was to investigate the phytochemistry of two species Sanicula europaea and Teucrium davaeanum which are traditionally used in treatment of wounds. Four compounds were isolated from the 80% methanolic extract of S. europaea; bis-(2-ethylhexyl) phthalate (1), palmitic acid (2), rosmarinic acid (3), saniculoside N (4). Compounds 1 and 2 were isolated for the first time from this species. The structure elucidation of the isolated compounds was on the basis of 1D, 2D NMR spectroscopy and mass spectrometry measurements. Two compounds were isolated from the crude glycosides extract of T.davaeanum; 6 is a phenylethanoid glycoside and 8 is an iridoid glycoside, from the data available these may be new compounds for which the names davaeanuside A and davaeanuside B are proposed respectively." The total polyphenol content of S. europaea L, T. davaeanum leaves-flowers and T. davaeanum stem were found to be 5.0, 1.20 and 0.65 mg per 100 mg dried plant material respectively. A study of the antioxidant activity of the 50 % ethanol extracts of S. europaea and T. davaeanum showed that on a mg/mg basis S. europaea and T. davaeanum have approximately 5%, 8 % antioxidant capacity of Trolox respectively. A study of the cytotoxic activity of davaeanuside A (6), iridoid glycoside (7), davaeanuside B (8) and saponin compound (10) isolated from the crude glycosides extract of T. davaeanum revealed that saponin compound (10) inhibited the growth of Hela cells by 50 % at 50 μg/ml, P< 0.001, but the other compounds did not show activities against the tested cell lines at 100 μg/ml. The results of this work provide some basis for the traditional use of these species in the treatment of wounds.
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Amann, Laura. "Development and Validation of an Analytical Method for Phenolic Acid Extraction from Cereals and Quantification using HPLC-UV." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-77227.
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Cereals are rich in phenolic acids, a group of secondary plant metabolites that are associated with reduced risk of chronic diseases. The objective was to develop and internally validate a method for extraction and quantification of phenolic acids in cereals using HPLC-UV and to apply this method for quantification of the content of phenolic acids in several species of Swedish cereals. Different procedures for extraction of phenolic acids from cereal grains using acid or base hydrolysis with and without subsequent enzymatic treatment were tested. Both the extraction procedure and the chromatographic conditions for quantification with HPLC-UV were optimized. Phenolic acids from 14 cereal samples, representing different cultivars of rye, wheat, barley, and oat, were extracted and analyzed under optimized conditions. Using the optimized method, 15 phenolic acids could be quantified with limits of detection and quantification ranging from 0.4 to 11.4 µg/g and from 1.3 to 38.0 µg/g, respectively. The hydrolysis procedure and further sample treatment showed a substantial effect on the yield of phenolic acids from cereals. The highest yield was achieved by 90‑minute base hydrolysis at room temperature using sodium hydroxide solution containing ascorbic acid and EDTA. Mean recoveries ranged from 88 to 108%. The following phenolic acids were found in the analyzed cereal grains with ferulic acid being the most abundant one: p‑hydroxybenzoic acid, vanillic acid, vanillin, caffeic acid, syringic acid, ferulic acid, sinapic acid, and 3,4‑dihydroxybenzaldehyde. A further compound was p‑coumaric acid or the co‑eluting syringaldehyde or a mixture of both. The content of phenolic acids in Swedish cereals ranged from 6 µmol/g DM in rye to 3 µmol/g DM in oat and a barley cultivar. In conclusion, a simple and accurate method for extraction and quantification of phenolic acids in cereals was developed and successfully applied.Getreide ist reich an Phenolsäuren, einer Gruppe pflanzlicher Sekundärmetabolite, die mit einem verringerten Risiko für chronische Erkrankungen in Verbindung gebracht wird. Ziel war es, eine Methode zur Phenolsäure-Extraktion aus Getreide und Quantifizierung mittels HPLC-UV zu entwickeln, intern zu validieren und diese im Anschluss anzuwenden, um den Phenolsäure-Gehalt in mehreren schwedischen Getreidearten zu quantifizieren. Verschiedene Verfahren zur Phenolsäure-Extraktion aus Getreide unter Verwendung von Säure- oder Basenhydrolyse mit oder ohne nachfolgender enzymatischer Hydrolyse wurden getestet. Es wurden sowohl das Extraktionsverfahren als auch die chromatographischen Bedingungen zur Quantifizierung mittels HPLC-UV optimiert. Phenolsäuren von 14 Getreideproben, darunter Kultivare von Roggen, Weizen, Gerste und Hafer, wurden unter optimierten Bedingungen extrahiert und analysiert. Mit der optimierten Methode konnten 15 Phenolsäuren mit Nachweisgrenzen von 0,4 bis 11,4 µg/g und Bestimmungsgrenzen von 1,3 bis 38,0 µg/g quantifiziert werden. Hydrolyseverfahren und weitere Probenbehandlung haben die Phenolsäure-Ausbeute von Getreide wesentlich beeinflusst. Die höchste Ausbeute wurde durch eine 90‑minütige Basenhydrolyse bei Raumtemperatur unter Verwendung von Natronlauge mit Ascorbinsäure und EDTA erzielt. Die mittlere Wiederfindung betrug 88 bis 108%. In den untersuchten Getreideproben wurden folgende Phenolsäuren gefunden mit Ferulasäure als häufigster Verbindung: p-Hydroxybenzoesäure, Vanillinsäure, Vanillin, Kaffeesäure, Syringasäure, Ferulasäure, Sinapinsäure und 3,4‑Dihydroxybenzaldehyd. Eine weitere Verbindung war p‑Cumarsäure oder der co‑eluierende Syringaldehyd oder eine Mischung aus beiden. Der Phenolsäure-Gehalt reichte von 6 µmol/g DM in Roggen bis 3 µmol/g DM in Hafer und einem Gerstenkultivar. Zusammenfassend wurde eine einfache und genaue Methode zur Phenolsäure-Extraktion und Quantifizierung in Getreide entwickelt und erfolgreich angewendet.
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Maleckienė, Rūta. "Rausvažiedės ežiuolės (Echinacea Purpurea (L.) Moench) ekstraktų, gautų skirtingais metodais, palyginimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080626_143812-69618.
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Rausvažiedė ežiuolė (Echinacea purpurea (L.) Moench) apibūdinama kaip priemonė skatinanti medžiagų apykaitą; stimuliuojanti metabolizmo pakitimus ir ląstelių natūralią gynybą esant lėtinėms ir ūmioms ligoms; antiseptikas; dezinfekuojantis žaizdas agentas; vaistas. Darbo tikslas buvo atlikti fenolinių junginių analizę rausvažiedės ežiuolės (Echinacea purpurea (L.) Moench) ekstraktuose, gautuose skirtingais metodais, naudojant spektrofotometrinį metodą ir efektyviąją skysčių chromatografiją. Darbo uždaviniai buvo optimizuoti ekstrakcijos sąlygas (maceracijos metodu) įvertinant skirtingas metanolio koncentracijas ir ekstrakcijos trukmės įtaką fenolinių junginių kiekybinei sudėčiai ekstraktuose; paruošti ekstraktus maceracijos, soksleto ir ekstrakcijos superkritiniais skysčiais metodais; optimizuoti efektyviosios skysčių chromatografijos sąlygas; atlikti kokybinę ir kiekybinę fenolinių junginių analizę Rausvažiedės ežiuolės ekstraktuose, įvertinant a) skirtingas ekstraktų paruošimo metodikas; b) skirtingas augalo dalis.
Tyrimo metu optimizuotos ekstrakcijos sąlygos (maceracijos metodu); nustatyta, kad daugiausiai fenolinių junginių išekstrahuota naudojant 70 % metanolį per pirmas 4 ekstrakcijos valandas. Paruošti ekstraktai maceracijos, soksleto ir ekstrakcijos superkritiniais skysčiais metodais. Spektrofotometru nustatyta, kad daugiausiai fenolinių junginių išekstrahuojama maceracijos metodu — 3 kartus daugiau nei soksleto metodu ir 14 kartų daugiau nei ekstrakcija... [toliau žr. visą tekstą]Echinacea purpurea (L.) Moench (family Asteraceae) herbal medicines and dietary supplements are traditionally used as immunostimulants in the treatment of inflammatory and viral diseases. Employed are roots and aerial parts. The main active compounds of Echinacea purpurea (L.) Moench are alkamides and polyacetylenes, caffeic acid derivatives, polysaccharides and glycoproteins. With regard to caffeic acid derivatives, several compounds have been identified from the hydrophilic fractions of Echinacea extracts, such as caftaric acid, chlorogenic acid, caffeic acid and cichoric acid. Cichoric acid is found to be the main phenolic compound in E. purpurea. From the caffeic acid derivatives, only cichoric acid has shown immunostimulatory properties, promoting phagocyte activity in vitro and in vivo. In addition, cichoric acid has antihyaluronidase activity, and has a protective effect on the free-radical-induced degradation of collagen. Cichoric acid has also shown antiviral activity and has recently been found to inhibit HIV-1 integrase and replication. Tasks of investigation: to prepare samples for phenolic acids analysis by supercritical fluid, soxhlet extractions and maceration methods and optimize SPE parameters. Evaluate amount of cichoric acid and compare it in different parts of plant by spectrophotometric method. Optimize HPLC analysis conditions and identify the main phenolic acids by HPLC. Compare amounts of phenolic acids between plant parts and extraction methods... [to full text]
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Paracatu, Luana Chiquetto. "Ácido cafeico e seus ésteres : inibição do "burst" oxidativo de neutrófilos e efeito anti-Helicobacter pylori /." Araraquara : [s.n.], 2012. http://hdl.handle.net/11449/93126.
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Orientador: Luiz Marcos da FonsecaBanca: Cibeli Bonacorsi
Banca: Valdecir Farias Ximenes
Resumo: A ação patogênica do Helicobacter pylori envolve a colonização do trato gastrointestinal e a produção de EROs por neutrófilos atraídos e ativados pelo agente da infecção. A reação mediada pelos PMN é, todavia, ineficaz para eliminar o H. pylori e as EROs contribuem para a lesão tecidual e desenvolvimento de gastrites e úlcera péptica. O ácido cafeico é um dos mais importantes compostos fenólicos, e apresenta diferentes propriedades biológicas, entre elas antioxidante e antimicrobiana. O objetivo deste estudo foi avaliar a atividade antioxidante e anti-H.pylori do ácido cafeico e seus ésteres. Foram avaliados os ésteres: cafelato de metila, cafelato de butila e cafelato de heptila e realizada uma comparação entre as propriedades antioxidantes do ácido cafeico e tais ésteres, por meio de ensaio de quimiluminescência dependente de luminol e lucigenina, ensaio de inibição da produção do ácido hipocloroso e também ensaios morfológicos com e sem a presença de NBT. Os resultados deste estudo mostraram que os ésteres do ácido cafeico apresentaram melhores resultados em comparação com o ácido cafeico para a capacidade antioxidante. O cafelato de heptila apresentou os melhores resultados para a quimiluminescência dependente de luminol e lucigenina induzida por H. pylori e/ou zymozan opsonizado na concentração de 10 µM e 1 µM . O efeito do ácido cafeico e seus ésteres, também foi estudado na inibição da produção de ácido hipocloroso por neutrófilos ativados com PMA. O cafelato de heptila novamente provou ser melhor em capacidade antioxidante, levando a crer que a lipofilicidade deste composto... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The pathogenic action of Helicobacter pylori involves the colonization of the gastrointestinal tract and ROS production by neutrophils attracted and activated by the agent of infection. However, the reaction mediated PMN is ineffective to remove the H. pylori and ROS contribute to tissue damage and development of gastritis and peptic ulcer. Caffeic acid is one of most important phenolic compounds, and has different biological properties including antioxidant and antimicrobial activities. The aim of this study was to evaluate the antioxidant and anti-Helicobacter pylori activity of caffeic acid and esters. Esters evaluated: methyl caffeic acid ester, butyl caffeic acid ester and heptyl caffeic acid ester and a comparison between the antioxidant properties of caffeic acid and these esters through luminol and lucigenin chemiluminescence assay dependent, inhibition of production of hypochlorous acid assay, morphological tests with and without the presence of NBT. The results of this study showed that the esters of caffeic acid had better results in comparison with caffeic acid to their antioxidant capacity. The heptyl caffeic acid ester showed the best results for the luminol and lucigenin dependent chemiluminescence induced by H. pylori and / or opsonized zymozan in the concentrations of 10 µM and 1 µM. The effect of caffeic acid and esters, was also studied in inhibiting of production of hypochlorous acid by neutrophils activated with PMA. The heptyl caffeic acid ester again proved to be better at antioxidant activity, implying that... (Complete abstract click electronic access below)
Mestre
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Michelin, Daniele Carvalho. "Estudo químico-farmacológico de Operculina macrocarpa (L.) urb. (Convolvulaceae) /." Araraquara : [s.n.], 2008. http://hdl.handle.net/11449/102459.
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Resumo: Operculina macrocarpa (L.) Urb., Convolvulaceae, popularmente conhecida como batata-de-purga ou jalapa, é utilizada pela população como laxante e no tratamento da leucorréia. O objetivo deste trabalho foi realizar o controle de qualidade da droga vegetal, otimizar o processo extrativo desta espécie, avaliar a atividade laxante e antioxidante da raiz desta planta, realizar ensaios toxicológicos e ainda caracterizar fitoquimicamente a espécie por CLAE (Cromatografia Líquida de Alta Eficiência) e EM (Espectrometria de Massas). Foram realizados testes farmacopéicos de controle de qualidade, que comprovaram a autenticidade e a qualidade da droga vegetal. Avaliou-se a atividade laxante de O. macrocarpa através de diferentes modelos experimentais de trânsito intestinal utilizando o extrato hidroetanólico, o chá, a resina e os ácidos caféico, clorogênico e ferúlico. Verificou-se que o extrato hidroetanólico, o chá e os ácidos fenólicos apresentaram atividade laxante no modelo experimental avaliado e para atividade antioxidante foi observada uma discreta atividade para o extrato, o chá e a resina comparados com o padrão de ácido caféico. Na avaliação toxicológica o extrato hidroetanólico e o chá apresentaram uma diminuição nos valores das transaminases séricas AST (Aspartato aminotransferase) e ALT (Alanina aminotransferase), sugerindo hepatotoxicidade. Foi traçado o perfil químico do extrato hidroetanólico, do chá e da resina onde foram identificados os ácidos caféico, ferúlico, clorogênico, metil-ferúlico, quínico, dicafeoil-quinico e dímero do ácido caféico por CLAE e EM. Os ácidos fenólicos identificados foram quantificados por CLAE. Os resultados obtidos neste estudo químico-farmacológico de Operculina macrocarpa são fundamentais para o futuro desenvolvimento de um produto farmacêutico... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: Operculina macrocarpa (L.) (Urb.), Convolvulaceae, popularly known as 'batata-depurga', is used by the population as a laxative and for the treatment of leucorrhea. The aim of this work was to carry out the quality control of vegetal drug, evaluate the antioxidant and laxative activity of the root of this plant, to carry out toxicology assays and phytochemical characterization by HPLC (High Performance Liquid Chromatography) and MS (Mass Spectrommetry) of this specie. Pharmacopeial tests of quality control had confirmed the authenticity and quality of sample. The laxative activity was evaluated by different experimental models for the hydromethanolic extract, tea, resin, and caffeic, chlorogenic and ferulic acid. The results showed that hydroethanolic extract, tea and phenolic acids had significant activity in experimental model tested. The results showed a little antioxidant activity for the extract, resin and tea when compared with standart caffeic acid. In the toxicological evaluation hydroethanolic extract and tea had presented alterations in the seric levels of transaminases ALT (Alanine aminotransferase) and AST (Aspartate aminotransferase) suggesting hepatotoxicity. Chemical profile of ethanolic extract, tea and resin was carried out by HPLC and MS and these techniques could identify caffeic, ferulic, chlorogenic, methylferulic, quinic, dicaffeoylquinic acids and a caffeic acid dimer. The phenolic acids were quantificated by HPLC. The results obtained in the chemical-pharmacological study of Operculina macrocarpa are fundamental for the future development of a pharmaceutical product with standarts of safety and efficacy... (Resumo completo clicar acesso electronic access below)
Orientador: Hérida Regina Nunes Salgado
Coorientador: Wagner Vilegas
Banca: Clélia Akiko Hiruma Lima
Banca: Luis Vitor Silva do Sacramento
Banca: Marco Vinícius Chaud
Banca: Dominique Corine Hermine Fischer
Banca: Hérida Regina Nunes Salgado
Doutor
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Kurth, Caroline [Verfasser], Georg [Akademischer Betreuer] Pohnert, and Rainer [Akademischer Betreuer] Beckert. "Sulfated phenolic acids as readily activatable storage forms of antifouling agents in marine plants / Caroline Kurth. Gutachter: Georg Pohnert ; Rainer Beckert." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2015. http://d-nb.info/1077478208/34.
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Kheder, Fadi. "Production et purification d'acide férulique estérases. Application à la synthèse d'esters phénoliques." Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL075N/document.
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L’induction de la synthèse d’une acide férulique estérase (AFE) a été étudiée chez Streptomyces ambofaciens ATCC 23877. L’activité la plus élevée a été détectée en présence de son de blé désamidonné ou de xylane d’avoine (0,22, 0,21 mU/mg protéine, respectivement). Des productions d’AFE en bioréacteur ont également été réalisées en utilisant 1% (p/v) de son de blé comme inducteur. Le niveau de production de l’AFE a été trois fois plus important en bioréacteur qu’en fiole d’Erlenmeyer. L’AFE de Streptomyces ambofaciens ATCC 23877 et celle de Humicola sp., présente dans un mélange enzymatique commercial (DepolTM 740L), ont été partiellement purifiées et caractérisées. A l’issue de la purification, l’activité AFE de Streptomyces ambofaciens ATCC 23877 a été trop faible pour pouvoir être utilisée ultérieurement en synthèse. Par contre, le potentiel de l’AFE de Humicola sp., concentrée par précipitation à l’acétone, pour la synthèse de différents esters phénoliques a été testé. Les meilleurs rendements de conversion ont été observés lors de l’absence de substitutions sur le cycle aromatique de l’acide phénolique ou en présence de groupements hydroxyles. Les synthèses en milieu non aqueux (M2B2) se sont montrées infructueuses en raison, peut-être, d’un effet néfaste du solvant sur l’enzymeThe induction of the ferulic acid esterase (FAE) synthesis was studied with Streptomyces ambofaciens ATCC 23877. The highest activity was detected in the presence of either destarched wheat bran or oat spelt xylan (0,22, 0,21 mU/mg protein, respectively). FAE productions in bioreactor were also carried out using 1% (w/v) of wheat bran as inducer. The FAE production level was three times higher in bioreactor than in Erlenmeyer flask. FAE of Streptomyces ambofaciens ATCC 23877 and that of Humicola sp., present in an enzymatic commercial mixture (DepolTM 740L), were partially purified and characterised. At the end of the purification, FAE activity of Streptomyces ambofaciens ATCC 23877 was too weak to be used later in synthesis. However, the FAE potential of Humicola sp., concentrated by acetone precipitation, for the synthesis of various phenolic esters was tested. The best conversion yields were observed in the absence of substitution on the phenolic acid aromatic cycle or in the presence of hydroxyl groups. The synthesis in non-aqueous medium (M2B2) were unsuccessful maybe because of an harmful effect of the solvent on the enzyme
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Jardini, Fernanda Archilla. "Avaliação da atividade antioxidante da romã (Punica granatum, L.) - participação das frações de ácidos fenólicos no processo de inibição da oxidação." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-30062008-163119/.
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Os antioxidantes de origem natural têm importância na área de alimentos, pois podem representar uma alternativa de substituição aos antioxidantes sintéticos. Os compostos fenólicos, presentes nos vegetais, desempenham importância na inibição da oxidação, A romã (Punica granatum, L.) é rica em compostos fenólicos como as antocianinas, flavonóides e ácidos fenólicos. Avaliou-se a atividade antioxidante da polpa e semente de romãs plantadas no Brasil (Pernambuco), e foi feita a obtenção dos extratos e frações de ácidos fenólicos da fruta, que foram submetidos aos testes de co-oxidação de substratos β- caroteno e ácido linoléico, em meio emulsionado, e ao método Rancimat, em meio lipídico. Também foi avaliado o comportamento cinético da atividade antioxidante para os extratos e frações de ácidos fenólicos. Verificou-se que os extratos aquosos da polpa e semente apresentaram significativa inibição da oxidação a concentrações baixas, em ambos os testes utilizados, fato atribuído à grande quantidade de compostos fenólicos presentes nestes extratos, em relação aos demais. A avaliação cinética dos extratos aquosos demonstrou que estes também foram mais eficientes ao longo do processo oxidativo, apresentando-se mais estáveis do que o antioxidante sintético BHT. As frações de ácidos fenólicos esterificados a compostos solúveis da polpa foi a fração que apresentou maior inibição da oxidação, e também maior quantidade de compostos fenólicos, apresentando uma atividade cinética bastante eficiente. Entretanto, as frações de ácidos fenólicos livres da polpa e semente apresentaram porcentagens de inibição da oxidação bastante altas a uma concentração menor. A semente da romã apresenta em sua composição de ácidos graxos o ácido graxo punícico. Este ácido é um isômero conjugado do ácido linolênico, e que constitui 58% da composição total de ácidos graxos da semente da fruta, sendo seu principal ácido graxo.The antioxidants of natural origin have an important role on food science, because they may substitute the synthetic antioxidants. The phenolic compounds of vegetables play an important role as oxidation inhibitors. The pomegranate (Punica granatum, L.) is rich in phenolic compounds as anthocianins, flavonoids and phenolic acids. The antioxidant activity of extracts and acid phenolic fractions obtained from the pulp and seeds of brazilian pomegranate (from Pernambuco) was evaluated, by the co-oxidation of β-carotene and linoleic acid assay and the Rancimat method. The kinetic behavior of the antioxidant activity of the extracts and acid phenolic fractions by the co-oxidation of β-carotene and linoleic acid test was evaluated, too. It was noted that the aquous extracts from the pulp and seeds have significant antioxidant activity at slow concentration. It was possible by the high content of phenolic compounds present on those extracts. The kinetic behavior showed that the aquous extracts was the most efficient along the oxidative process, showing larger stability than the antioxidant BHT. The pulp\'s of bound acid phenolic fraction by soluble compounds was the most efficient among the acid phenolic fractions, and it has major amount of phenolic compounds. The pomegranate seed has the punicic acid on its fatty acid composition. The punicic acid is a I conjugated inolenic acid isomer.The punicic acid is present at 58% from the total fatty acids from the fruit, being its principal fatty acid.
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Strapcová, Zuzana. "Chemická a senzorická charakterizace ciderů vyrobených z odrůd jablek charakteristických pro ČR." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401939.
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This master thesis deals with the investigation of selected chemical and sensory characteristics of ciders, which were made from four selected apple varieties. The theoretical part describes the chemical composition of apples, cider, the technology of production and production in the world. The next section describes the analytical methods used to determine chemical characteristics not only in ciders but also in other alcoholic beverages. The experimental part focuses on the determination of chemical characteristics such as the content of organic acids, carbohydrates, total phenolic content, alcohol antioxidant activity and elemental composition. The purpose of the work was to find out how different varieties differ in chemical composition. The produced ciders were subjected to sensory analysis to evaluate the selected cider sensory parameters, which were in the natural state and with the addition of carbon dioxide. The results show that ciders of different varieties differ in chemical composition. Malic acid was the most cider's abundant of the organic acids in the range of 2759 – 4411 mg·l-1. Another acid represented was lactic acid in the range of 166,2 – 288,1 mg·l-1. The glucose content of each cider was determined between 845,3 – 1159,8 mg·l-1and fructose 32,6 – 406,7 mg·l-1. Potassium 944,29 – 1073,98 mg·l-1 was the most represented of all elements. The total phenolic content was determined to be in the range of 164,2 – 214,1 mg of GAE·l-1and the antioxidant activity of 0,192 – 0,318 mg·l-1. These differences in chemical composition were also reflected in sensory evaluation. According to the overall assessment, the best cider was made from the Granny Smith variety, which contained the most organic acids and carbohydrates. It has been found that by adding carbon dioxide, sensory parameters such as colour, taste and smell are altered.
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Spáčil, Zdeněk. "Mass Spectrometry of Biologically Active Small Molecules : Focusing on polyphenols, alkaloids and amino acids." Doctoral thesis, Stockholms universitet, Institutionen för analytisk kemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-33233.
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The foci of this dissertation are on advanced liquid chromatography (LC) separation and mass spectrometry (MS) techniques for the analysis of small bioactive molecules. In addition to discussing general aspects of such techniques the results from analyses of polyphenols (PPs), alkaloids and amino acids published in five appended studies are presented and discussed. High efficiency and well understood principles make LC the method of choice for separating analytes in many kinds of scientific investigations. Moreover, when LC is coupled to an MS instrument, analytes are separated in two stages: firstly they are separated and pre-concentrated in narrow bands using LC and then separated according to their mass-to-charge (m/z) ratios in the MS instrument. Some MS instruments can provide highly accurate molecular weight measurements and mass resolution allowing identification of unknown compounds based purely on MS data, thus making prior separation unnecessary. However, prior separation is essential for analyzing substances in most complex matrices – especially useful is the ultra-high performance LC (UHPLC). The advantages of using UHPLC rather than HPLC for the analysis of PPs in tea and wine were evaluated in one of the studies this thesis is based upon. The phenolic composition of red wine was also examined, using a novel LDI technique, following solid phase extraction (SPE). A class of small aromatic molecules (medicinally important alkaloids) also proved to be amenable to straightforward analysis, by thin layer chromatography (TLC) work-up followed by LDI-MS. Finally, a LC-MS method for monitoring neurotoxins (β-N-methyl-amino-L-alanine and 2,3-diaminobutyric acid) in complex biological matrices was developed and applied. Overall, the studies show that careful attention to the physicochemical properties of analytes can provide insights that can greatly facilitate the development of alternative methods to analyze them, e.g. by LDI.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: In press. Paper 5: Manuscript.
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Ndolo, Victoria Uchizi. "Characterisation of chemical components in manually isolated aleurone and associated layers from maize, wheat and barley kernels." Elsevier, 2013. http://hdl.handle.net/1993/30914.
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Health benefits related to consumption of whole grains have been attributed in part to phytochemical and micronutrient composition. Understanding the composition, structure and distribution of these components in different cereal grains is of potential importance in aiding the selection of whole grains and their processed fractions for inclusion in the diet, and as ingredients in development of new food products. The aim of this research was to characterise the chemical components in the botanical fractions of yellow corn, barley, wheat. Manual separation, a tedious and laborious technique that yields pure fractions, suitable for compositional analysis, was used to separate whole grains into pericarp, aleurone layer, germ and endosperm fractions. Component identification and quantification of tissue components was accomplished by several techniques. The study also explored the possibility of using spectral characteristics fluorescence intensity values to provide rapid estimates of the concentrations and distribution of ferulic acid (FA), a major phenolic compound in cereal grains. While composition of phenolic acids and carotenoids was similar, the distribution was significantly different (P < 0.05) among cereal types and grain fractions. Phenolic acids were concentrated in pericarp and aleurone fractions, followed by the germ and the endosperm had the lowest levels. Yellow corn exhibited the highest values. Carotenoids, lutein and zeaxanthin were concentrated in the germ and aleurone layer of wheat and barley while in yellow corn it was in the endosperm and aleurone layer. This is the first study to report on carotenoid composition of aleurone fractions. Mineral elements, thiamine and niacin were higher in wheat aleurone than in purple barley and yellow corn aleurone layers. These findings suggest that yellow corn aleurone layers have potential as a functional food ingredient despite the low micronutrient content. A positive, significant correlation (r= 0.421, p < 0.0001) was found between fluorescence intensity values and ferulic acid concentration. Thus, fluorescence intensity profiles are a promising approach for rapid assessment of FA concentration in grain in-situ. This work has provided information that would act as a database for selection of cereal fractions and guide the miller to obtain grain fractions with enriched levels of phytochemicals and micronutrients.February 2016
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Vera, Krimer Malešević. "Fenolni potencijal uljanih pogača." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=101055&source=NDLTD&language=en.
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U okviru disertacije ispitana je mogućnost eksploatacije nusproizvoda (nastalih tokom procesa hladnog presovanja ulja) kao izvora prirodnih fenolnih kiselina. Odabir je obuhvatio uzorke uljane tikve, crnog kima, lana i nara. Radi oslobađanja vezanih fenolnih kiselina i u cilju procene njihovog ukupnog sadržaja i distribucije (u čvrstim uzorcima), primenjena je alkalna hidroliza sa dodatkom L-askorbinske kiseline i EDTA. Dobijeni rezultati pokazuju da se sve analizirane pogače mogu se koristiti za dobijanje vrednih fenolnih kiselina, pri čemu raspodela fenolnih kiselina zavisi od vrste uljane pogače. Koncentracija slobodnih fenolnih kiselina se pokazala značajnom za pogaču uljane tikve, estarski vezanih za pogače nara i lana, a nerastvornih-vezanih za pogače crnog kima i nara. Od svih analiziranih uzoraka kora nara je sadržala najviše estarski vezanih fenolnih kiselina zahvaljujući veoma visokom sadržaju galne kiseline. Nakon određivanja fenolnih kiselina u nusproizvodima, analiza glavnih komponenti (PCA) je omogućila razdvajanje biljnih uzoraka u grupe prema poreklu i smanjila broj fenolnih kiselina neophodnih za njihovu karakterizaciju, što može imati potencijalnu primenu u skriningu fenolnih kiselina i određivanju kvaliteta/autentičnosti uljarica i njihovih nusproizvoda.Within the thesis, the possibility of by-products (formed during the process of cold oil pressing) exploitation as a source of natural phenolic acids was examined. Selection of the samples included pumpkin, black cumin, flax and pomegranate. For the purpose of bonded phenolic acids release and for the total phenolic acids content and distribution (in the solid samples) assessment, the alkaline hydrolysis with the addition of L-ascorbic acid and EDTA was employed. The results show that all analyzed cakes can be used to obtain valuable phenolic acids, while the distribution of phenolic acids depends on the type of oil cakes. The concentration of free phenolic acids proved to be significant for a pumpkin oil cake, ester for pomegranate and flax oil cakes, and insoluble-bound for black cumin and pomegranate oil cakes. Of all analyzed samples, pomegranate hull contains the highest content of ester-linked phenolic acids, due to a very high content of gallic acid. After phenolic acids determination in the by-products, principal components analysis (PCA) allowed the separation of plant samples in groups according to origin and reduced the number of phenolic acids necessary for their characterization, which may have potential application in the screening of phenolic acids and determining the quality/authenticity oilseeds and their by-products.
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Jardini, Fernanda Archilla. "Atividade dos compostos fenólicos antioxidantes da romã (Púnica granatum, L.) -- avaliação in vivo e em culturas de células." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-31052010-150831/.
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Os radicais livres são formados constantemente em nosso organismo, e em quantidades controladas desempenham alguns papéis fisiológicos. Entretanto, sua presença em quantidades acima daquelas aceitáveis passa a ser um fator de risco para funcionamento adequado do organismo. Muitas doenças crônicas degenerativas têm sua origem no desequilíbrio do estado redox. Apesar de possuir um sistema de proteção antioxidante endógeno, o organismo pode ser beneficiado pela presença de compostos antioxidantes exógenos, como os compostos fenólicos encontrados em alguns alimentos. A romã (Punica granatum, L) é uma fruta que apresenta elevados conteúdos destes compostos. Foram obtidos os extratos e as frações de ácidos fenólicos da polpa e das sementes da fruta, e avaliou-se a capacidade antioxidante através de três métodos in vitro: o de co-oxidação de substratos (β- caroteno e ácido linoléico), o do radical DPPH• e o ORAC. Em todos os testes foram obtidos resultados que indicaram uma elevada atividade antioxidante, principalmente para a fração de ácidos fenólicos livres (AFL) da polpa. Frente a estes dados, a fração foi submetida a um ensaio de transporte celular, o qual foi possível verificar que os diferentes ácidos fenólicos ali encontrados foram capazes de atravessar a membrana celular. A fração AFL da polpa propiciou uma redução na produção de espécies reativas intracelulares e efeitos sobre a proliferação e a viabilidade em células das linhagens Caco-2, HeLa e MDCK. Por fim, o ensaio in vivo avaliou, sob condições fisiológicas normais, o efeito do extrato aquoso e da fração AFL sobre a oxidação lipídica e na atividade do sistema enzimático de defesa antioxidante. O tecido cerebral apresentou uma redução significativa nos níveis de lipoperoxidação. A atividade das enzimas superóxido dismutase, catalase e glutationa peroxidase apresentou resultados bastante díspares e sugerem que as respostas não seguem um padrão único e podem variar de acordo com o órgão analisado, respondendo com o aumento ou a diminuição da atividade enzimática de acordo com suas funções fisiológicas.Free radicals are continuosly formed in our organism, and under suitable amounts they play physiological roles. However, when there´s a higher presence in their levels than the acceptable ones, they turn into a risk factor to the adequate work of the organism. Most of the degenerative illness are originated from the redox state desequilibrium. Although the organism has an endogenous antioxidant defence system, it may be beneficiated by the presence of antioxidant compounds of exogenous origen, as the phenolic compounds that are found in some kinds of food. The pomegranate (Punica grantum, L.) is a high phenolic compound fruit. The extracts and phenolic fractions both from the pulp and seeds of the fruit were obtained and their antioxidant activity was obtained using three in vitro methods: the co-oxidation of substrates (β-carotene and linoleic acid), the DPPH• radical and the ORAC. For all of them the results have showed a great antioxidant activity, higher than those of the free phenolics acids´fraction (FPA) of the pulp. Face to these data, the fraction was taken to a cellular transport assay, which was possible to verify that the different phenolic acids present at FPA were able to cross the cellular membrane. The FPA pulp´s fraction provocated a down in production of the the intracelular reactive species and had effects into the cellular proliferation and viability of the Caco-2, HeLa and MDCK cells. Finally, the in vivo tryout was made using rats submitted to normal physiologic conditions and the effects of the aquous extract and FPA fraction over the lipidic oxidation and the activity of the enzymatic system of antioxidant defence were avaliated. The brain tissue showed a significant reduction about the lipoperoxidation levels. The results about the activity of the enzymes superoxide dismutase, catalase and glutathione peroxidase were so different between themselves, which suggests that the enzymes don´t follow an only standard of response, and the reply can vary in accordance with the analyzed organ. The increase or the reduction of the enzymatic activity can occur by the physiologic conditions that the organ is able to do.
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Fukuji, Tatiana Shizue. "Propostas metodologicas para componentes em matrizes alimenticias, alimentos enriquecidos e contaminantes utilizando eletroforese capilar acoplada a espectrometria de massas e detecção UV/VIS." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-28032012-100624/.
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O trabalho envolve o desenvolvimento de métodos para análise de alimentos visando a determinação de ácidos fenólicos em frutas, ácido fólico em farinhas enriquecidas e corantes Sudan em produtos de pimenta utilizando eletroforese capilar nos modos de detecção UV e MS. A separação de dez ácidos fenólicos (ácidos clorogênico, siríngico, p-cumárico, benzóico, p-hidroxibenzóico, ferúlico, vanílico, cafeico, gálico e protocatecuico) foi obtida por eletroforese capilar de zona (CZE). Um eletrólito composto de 50 mmol L-1 de tetraborato e 7,5% metanol (v/v) permitiu a separação em linha de base dos dez ácidos fenólicos em menos de 15 minutos. A fim de promover o \"clean-up\", pré-concentração e liberação dos ácidos fenólicos esterificados, um procedimento de extração líquido-líquido seguido pela hidrólise alcalina foi realizado. O método foi validado obtendo-se limites de detecção de 1,63-3,80 µg mL-1 e limites de quantificação de 4,95-11,39 µg mL-1. O método otimizado foi aplicado para análise de frutas como a abiu-roxo (Chrysophyllum caimito), amora silvestre (Morus nigra L.) e tomate de árvore (Cyphomandra betacea), identificando os ácidos fenólicos na fração livre e hidrolisada. Este trabalho também otimizou o processo de extração e caracterizou a composição de ácidos fenólicos na forma livre e hidrolisada presentes no açaí Juçara (Euterpe precatória Mart.), açaí do Pará (Euterpe oleracea) e em produtos comercias de açaí como polpa congelada e \"açaí na tigela\". Para a determinação do ácido fólico, estudos de pré-concentração online foram realizados. A focalização do ácido fólico foi obtida por CZE e MEKC, devido a fenômenos de isotacoforese transiente. Um método de extração simples baseado na dissolução da farinha em solução de Na2HPO4 seguida de ultrassom e adição de HCl concentrado foi adotado. Entretanto, a detecção do ácido fólico no extrato foi obtida por MEKC com injeção de grande volume de amostra em condições eletroforéticas de 40 mmol L-1 TBS e 30 mmol L-1 SDS, 15 kV a 310 nm. Os limites de detecção e de quantificação atingidos foram de 0,047 e 0,14 µg mL-1, sendo adequados para quantificação do ácido fólico em farinhas de trigo. Um método para determinação de corantes Sudan (I, II, III e IV) em alimentos foi desenvolvido por cromatografia eletrocinética micelar (MEKC) com preenchimento parcial do capilar. A separação dos quatro corantes foi obtida utilizando-se um preenchimento de 25% do capilar (volume total) com eletrólito composto por 40 mmol L-1 NH4HCO3, 25 mmol L-1 SDS e 32,5% ACN (v/v). O restante do capilar foi preenchido com um tampão composto de 40 mmol L-1 NH4HCO3 e 32,5% (v/v) de ACN. Após otimização do método por CE-UV o método foi aplicado para o acoplamento ao CE-MS. Para detecção dos compostos no MS os parâmetros de ionização foram otimizados. A separação em linha de base dos quatro compostos foi obtida em menos de 10 min com limites de detecção de 0,57 a 0,75 µg mL-1 para detecção no UV-Vis e 0,05 a 0,2 µg mL-1 para detecção no MS. O método foi eficaz para a determinação destes corantes adicionados a amostras de molho de tomate e pimenta e chilli em póThe present work involves the development of methods for food analysis in order to determinate phenolic acids in fruits, folic acid in enriched flour and Sudan dye in chilli products by capillary electrophoresis with UV/Vis and MS detection. The separation of ten phenolic acids (benzoic, caffeic, chlorogenic, p-coumaric, ferulic, gallic, p-hydroxybenzoic, protocatechuic, syringic, and vanillic acid) was obtained by capillary zone electrophoresis (CZE). An electrolyte composed by 50 mmol L-1 of tetraborate and 7,5% methanol (v/v) allowed the baseline resolution of all phenolic acids under investigation in less than 15 min. In order to promote sample clean up, to preconcentrate the phenolic fraction and to release esterified phenolic acids from the fruit matrix, elaborate liquid-liquid extraction procedures followed by alkaline hydrolysis were performed. The proposed method was validated with limits of detection of 1.63-3.80 µg mL-1 and limits of quantification of 4.95-11.39 µg mL-1. The optimized method was applied to evaluation of phenolic contents of abiu-roxo (Chrysophyllum caimito), wild mulberry (Morus nigra L.) and tree tomato (Cyphomandra betacea). This work also optimized the extraction process and characterized the free and hydrolysed forms of phenolic acids in Juçara açaí (Euterpe precatória Mart.), Pará´s açaí (Euterpe oleracea) and commercial products such as frozen pulp and açaí desserts. For the determination of folic acid, on-line preconcentration studies were performed. The focalization of folic acid was obtained by CZE and MEKC by transient isotacophoresis. A simple method of extraction based on dissolution of flour in a Na2HPO4 solution followed by ultrasonication and the addition of concentrated HCl was adopted. However, the detection of folic acid in flour extract was obtained by MEKC with the large volume sample injection with eletrophoretic conditions of 40 mmol L-1 TBS and 30 mmol L-1 SDS, 15 kV and 310 nm. The limits of detection and quantification reached were 0.047 and 0.14 µg mL-1, which are suitable limits to quantify folic acid in enriched wheat flours. A method of Sudan dyes (I, II, III and IV) was developed by micellar electrokinetic chromatography (MEKC) with partial filling technique. Filling 25 % of the capillary with a MEKC solution containing 40 mmol L-1 NH4HCO3, 25 mmol L-1 SDS and 32.5 % ACN (v/v), a baseline separation of the four azo-dyes was obtained. The rest of capillary was filled with 40 mmol L-1 NH4HCO3 and 32.5 % ACN (v/v). After the optimization by CE-UV the method was applied to CE-MS coupling. To detect the compounds in MS the ionization parameters were optimized. The baseline separation of four compounds was obtained in less than 10 min with limit of detection within 0.57 to 0.75 µg mL-1 to UV-Vis detection and 0.05 to 0.2 µg mL-1 to MS detection. The method was efficient in the determination of these dyes spiked in tomato chilli sauces and chilli powder.
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Camargo, Adriano Costa de. "Hurdles and potentials in value-added use of peanut and grape by-products as sources of phenolic compounds." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-09112016-171820/.
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Recent studies have demonstrated that peanut and grape processing by-products may be richer sources of bioactive compounds as compared to their original raw material and feedstock; however, before their application as a source of nutraceuticals or in the prevention of lipid oxidation in food systems, certain technological challenges have to be addressed. This study discusses recent advances in the application of plant food processing by-products as sources of phenolic compounds with special emphasis on the profiling and screening of phenolics using high-performance liquid chromatography-mass spectrometry, their potential health benefits, and microbiologial safety. The major findings are summarized in chapters 2, 3, and 4. The first chapter deals with phenolics from grape by-products. In general, insoluble-bound phenolics were more effective in inhibiting copper-induced human LDL-cholesterol oxidation in vitro than free and esterified phenolics. Phenolic extracts from all fractions inhibited peroxyl radical-induced DNA strand breakage. The third chapter brings about the effects of gamma-irradiation on the microbial growth, phenolic composition, and antioxidant properties of peanut skin. Gamma-irradiation at 5.0 kGy decreased the microbiological count of the product. Total phenolic and proanthocyanidin contents, ABTS radical cation, DPPH radical, hydrogen peroxide, and hydroxyl radical scavenging capacities as well as the reducing power of the sample were increased upon gamma-irradiation in both the free and insoluble-bound phenolic fractions. The bioactivity of the free phenolics against in vitro human LDL-cholesterol oxidation and copper induced DNA strand breakage was improved upon gamma-irradiation. Phenolic compounds were positively or tentatively identified and their distribution was in the decreasing order of free > esterified > insoluble-bound forms. Procyanidin dimer A was increased in all phenolic fractions, whereas procyanidin dimer B decreased. Gamma-irradiation induced changes may be explained by molecular conversion, depolymerization, and cross-linking. In the fourth chapter, the ability of selected enzymes in improving the extraction of insoluble-bound phenolics from the starting material (experiment I) or the residues containing insoluble-bound phenolics (experiment II) were evaluated. Pronase and Viscozyme improved the extraction of insoluble-bound phenolics. Viscozyme released higher amounts of gallic acid, catechin, and prodelphinidin dimer A compared to Pronase treatment. Furthermore, p-coumaric and caffeic acids, as well as procyanidin dimer B, were extracted with Viscozyme but not with Pronase treatment. Solubility plays an important role in the bioavailability of phenolic compounds, hence this study may assist in better exploitation of phenolics from winemaking by-products as functional food ingredients or supplements.Estudos recentes têm demonstrado que subprodutos da indústria processadora de amendoim e uva podem ser mais ricos em compostos bioativos em comparação às suas matérias-primas. No entanto, alguns desafios tecnológicos precisam ser enfrentados antes da sua aplicação como fonte de compostos nutracêuticos ou na prevenção da oxidação lipídica em sistemas alimentares. Este estudo discute os recentes avanços na aplicação de subprodutos da indústria processadora de amendoim e uva como fontes de compostos fenólicos. Especial ênfase foi dada a sua caracterização por cromatografia líquida acoplada à espectrometria de massas, aos potenciais benefícios à saúde e à segurança microbiológica. As principais conclusões estão apresentadas nos capítulos 2, 3 e 4. O primeiro capítulo trata de compostos bioativos de subprodutos da indústria de suco de uva e da produção vinícola. A fração da qual foram extraídos os compostos fenólicos ligados à parede celular foi predominante. Em geral, esta fração também foi a mais eficaz na inibição da oxidação do LDL - colesterol in vitro quando comparada à fração que continha os fenólicos livres e os esterificados. Os compostos fenólicos de todas as frações inibiram o dano oxidativo ao DNA induzido por radicais peroxila. O terceiro capítulo fala sobre os efeitos da irradiação gama sobre a carga microbiana, a composição fenólica e as propriedades antioxidantes da película de amendoim. A irradiação gama (5,0 kGy) diminuiu a contagem microbiana do produto. Os compostos fenólicos totais, o teor de proantocianidinas e a capacidade dos extratos em neutralizar radicais como o ABTS, DPPH e espécies reativas de oxigênio como o peróxido de hidrogênio e radicais hidroxila, assim como o poder redutor da amostra, aumentaram devido à irradiação gama em ambas as frações (contendo fenólicos livres e ligados à parede celular). A bioatividade dos compostos fenólicos livres contra a oxidação do LDL-colesterol in vitro e contra os danos oxidativos ao DNA aumentou com a irradiação gama. Os compostos fenólicos foram positivamente ou tentativamente identificados, distribuindo-se entre: fenólicos livres > esterificados > ligados. Houve aumento na concentração de dímeros de procianidina A em todas as frações, enquanto a concentração de dímeros de procianidina B diminuiu. Essas alterações podem ser explicadas pela conversão molecular, despolimerização e formação de ligações cruzadas. No quarto e último capítulo, enzimas selecionadas foram aplicadas à matéria-prima inicial (experimento I) ou nos resíduos contendo apenas compostos fenólicos insolúveis (experimento II). Pronase e Viscozyme aumentaram a extração de compostos fenólicos insolúveis (ligados à parede celular). Viscozyme liberou maiores quantidades de ácido gálico, catequina e dímero de prodelfinidina A em comparação ao tratamento com Pronase. Além disso, os ácidos p-cumárico e ácido caféico, bem como o dímero de procianidina B, foram extraídos com Viscozyme, mas não com Pronase. A solubilidade desempenha um papel importante na biodisponibilidade de compostos fenólicos. Desta forma, o terceiro estudo oferece uma alternativa para a exploração de compostos fenólicos de subprodutos da indústria vinícola como ingredientes alimentares com propriedades funcionais ou suplementos alimentares.
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Comunian, Talita Aline. "Simultaneous encapsulation of echium (Echium Plantagineum L.) seed oil, phytosterols and phenolic compounds: characterization and application of microcapsules." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-23022018-135021/.
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The consumption of omega-3 fatty acids and phytosterol promotes the reduction of cholesterol and triacylglycerol levels. However, such compounds are susceptible to oxidation, which hampers their application. First, the aim of this work was to encapsulate echium oil (Echium plantagineum L.), source of omega-3 fatty acids, with hydrophilic phenolic compounds (sinapic acid and rutin) by double emulsion followed by complex coacervation in order to evaluate the best hydrophilic phenolic compound. In this case, sinapic acid showed better performance as antioxidant. Then, the second objective of this work was to study the microencapsulation of echium oil by complex coacervation using gelatin-arabic gum and gelatin-cashew gum as wall materials and sinapic acid and transglutaminase as crosslinkers. In this step, it was possible to observe that sinapic acid, besides to be an antioxidant, could also act as crosslinker. So, the third objective was to study the effect of sinapic acid in echium microparticles obtained by emulsion followed by spray or freeze drying using arabic gum as carrier agent in order to compare different encapsulation techniques. In addition to these methods, the fourth objective was to compare these techniques already mentioned to the combination of microfluidic devices and ionic gelation in order to encapsulate echium oil. In this case, sinapic acid and quercetin were also incoporated in the microcapsules. All the microcapsules/ microparticles obtained in the mentioned different techniques presented characteristics feasible for application and also promoted the protection of the oil. However, the encapsulation by complex coacervation and the addition of sinapic acid as crosslinkers was the method choosen for the coencapsulation of echium oil and phytosterols since presented the better results. Moreover, the treatment GA075 (microcapsule with gelatin-arabic gum as wall materials and 0.075g sinapic acid/ g gelatin) promoted the better protection to the encapsulated compounds. In this way, this treatment was applied into yogurt and compared to the one with the compounds nonencapsulated and the yogurt control. The yogurt containing microcapsules, presented a pH range from 3.89-4.17 and titratable acidity range from 0.798-0.826%, with good sensorial acceptance. It was possible to apply the microcapsules in yogurt, without compromising the rheological properties and physicochemical stability of the product, obtaining a functional product rich in omega-3 fatty acids, phytosterols and phenolic compound.O consumo de ácidos graxos ômega-3 e fitosterol promove a redução dos níveis de colesterol e triacilglicerol. No entanto, esses compostos são susceptíveis à oxidação, o que dificulta sua aplicação. Primeiramente, o objetivo deste trabalho foi encapsular o óleo de echium (Echium plantagineum L.), fonte de ácidos graxos ômega-3, com compostos fenólicos hidrofílicos (ácido sinápico e rutina) por emulsão dupla seguida de coacervação complexa com intuito de avaliar o melhor composto fenólico hidrofílico. Neste caso, o ácido sinápico apresentou melhor desempenho como antioxidante. Em seguida, o segundo objetivo deste trabalho foi estudar a microencapsulação do óleo de echium por coacervação complexa utilizando as combinações gelatina-goma arábica e gelatina-goma de caju como materiais de parede e ácido sinápico e transglutaminase como agentes de reticulação. Nesta etapa, foi possível observar que o ácido sinápico, além de ser um antioxidante, também pode atuar como agente de reticulação. Assim, o terceiro objetivo foi estudar o efeito do ácido sinápico em micropartículas de óleo de echium obtidas por emulsão seguida de atomização ou liofilização utilizando goma arábica como agente carreador, com a finalidade de comparar diferentes técnicas de encapsulação. Além desses métodos, o quarto objetivo foi comparar essas técnicas já mencionadas com a combinação de dispositivos microfluídicos e gelificação iônica utilizando o óleo de echium como composto bioativo. Neste caso, o ácido sinápico e a quercetina também foram incorporados nas microcápsulas. Todas as microcápsulas/ micropartículas obtidas pelas diferentes técnicas mencionadas apresentaram características viáveis para aplicação e também promoveram a proteção do óleo. No entanto, a encapsulação por coacervação complexa e a adição de ácido sinápico como reticulante foi o método escolhido para a coencapsulação de óleo de echium e fitosteróis, uma vez que apresentou melhor resultado. Além disso, o tratamento GA075 (microcápsula com gelatina-goma arábica como materiais de parede e 0,075g de ácido sinápico/ g gelatina) promoveu a melhor proteção aos compostos encapsulados. Desta forma, este tratamento foi aplicado em iogurte e comparado com o mesmo adicionado dos compostos não encapsulados e o iogurte controle. O iogurte contendo microcápsulas apresentou faixa de pH de 3,89-4,17 e acidez titulável de 0,798-0,826 %, com boa aceitação sensorial. Foi possível a aplicação das microcápsulas no iogurte, sem comprometer as propriedades reológicas e a estabilidade físico-química do produto, obtendo um produto funcional rico em ácidos graxos ômega-3, fitosteróis e compostos fenólicos.
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Reddivari, Lavanya. "Influence of genetic variability on specialty potato functional components and their effect on prostate cancer cell lines." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1330.
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Michelin, Daniele Carvalho [UNESP]. "Estudo químico-farmacológico de Operculina macrocarpa (L.) urb. (Convolvulaceae)." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/102459.
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Universidade Estadual Paulista (UNESP)
Operculina macrocarpa (L.) Urb., Convolvulaceae, popularmente conhecida como batata-de-purga ou jalapa, é utilizada pela população como laxante e no tratamento da leucorréia. O objetivo deste trabalho foi realizar o controle de qualidade da droga vegetal, otimizar o processo extrativo desta espécie, avaliar a atividade laxante e antioxidante da raiz desta planta, realizar ensaios toxicológicos e ainda caracterizar fitoquimicamente a espécie por CLAE (Cromatografia Líquida de Alta Eficiência) e EM (Espectrometria de Massas). Foram realizados testes farmacopéicos de controle de qualidade, que comprovaram a autenticidade e a qualidade da droga vegetal. Avaliou-se a atividade laxante de O. macrocarpa através de diferentes modelos experimentais de trânsito intestinal utilizando o extrato hidroetanólico, o chá, a resina e os ácidos caféico, clorogênico e ferúlico. Verificou-se que o extrato hidroetanólico, o chá e os ácidos fenólicos apresentaram atividade laxante no modelo experimental avaliado e para atividade antioxidante foi observada uma discreta atividade para o extrato, o chá e a resina comparados com o padrão de ácido caféico. Na avaliação toxicológica o extrato hidroetanólico e o chá apresentaram uma diminuição nos valores das transaminases séricas AST (Aspartato aminotransferase) e ALT (Alanina aminotransferase), sugerindo hepatotoxicidade. Foi traçado o perfil químico do extrato hidroetanólico, do chá e da resina onde foram identificados os ácidos caféico, ferúlico, clorogênico, metil-ferúlico, quínico, dicafeoil-quinico e dímero do ácido caféico por CLAE e EM. Os ácidos fenólicos identificados foram quantificados por CLAE. Os resultados obtidos neste estudo químico-farmacológico de Operculina macrocarpa são fundamentais para o futuro desenvolvimento de um produto farmacêutico...
Operculina macrocarpa (L.) (Urb.), Convolvulaceae, popularly known as 'batata-depurga', is used by the population as a laxative and for the treatment of leucorrhea. The aim of this work was to carry out the quality control of vegetal drug, evaluate the antioxidant and laxative activity of the root of this plant, to carry out toxicology assays and phytochemical characterization by HPLC (High Performance Liquid Chromatography) and MS (Mass Spectrommetry) of this specie. Pharmacopeial tests of quality control had confirmed the authenticity and quality of sample. The laxative activity was evaluated by different experimental models for the hydromethanolic extract, tea, resin, and caffeic, chlorogenic and ferulic acid. The results showed that hydroethanolic extract, tea and phenolic acids had significant activity in experimental model tested. The results showed a little antioxidant activity for the extract, resin and tea when compared with standart caffeic acid. In the toxicological evaluation hydroethanolic extract and tea had presented alterations in the seric levels of transaminases ALT (Alanine aminotransferase) and AST (Aspartate aminotransferase) suggesting hepatotoxicity. Chemical profile of ethanolic extract, tea and resin was carried out by HPLC and MS and these techniques could identify caffeic, ferulic, chlorogenic, methylferulic, quinic, dicaffeoylquinic acids and a caffeic acid dimer. The phenolic acids were quantificated by HPLC. The results obtained in the chemical-pharmacological study of Operculina macrocarpa are fundamental for the future development of a pharmaceutical product with standarts of safety and efficacy... (Resumo completo clicar acesso electronic access below)
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Ziółkowska, Anna. "Przemiany związków fenolowych w glebach łąkowych." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2019. http://dlibra.utp.edu.pl/Content/1245.
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Celem badań niniejszej pracy było określenie roli związków fenolowych w procesach przekształceń materii organicznej gleb łąkowych, prowadzących do powstania substancji humusowychThe aim of the research of this dissertation has been to determine the role of phenolic compounds in the processes of transformations of organic matter of meadow soils leading to the formation of humus substances
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Kamandulis, Mintautas. "Flavonoidų ir fenolinių rūgščių analizė kanadinės jakšūnės Desmodium canadense (L.) DC. žolėje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060706_143036-52316.
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Plants have many useful substances – and one of them is flavonoids with other phenolic compounds. This is a very big group of biological active compounds. Flavonoids have been referred to as "nature's biological response modifiers" because of their ability to modify the body's reaction to other compounds such as allergens, viruses, and carcinogens. They show anti-allergic, anti-inflammatory, and anti-cancer activity. In addition, flavonoids act as powerful antioxidants, providing remarkable protection against oxidative and free radical damage. As a result, consumers and food manufacturers have become increasingly interested in flavonoids for their healthful properties, especially their potential beneficial role in the prevention of cancer and cardiovascular diseases. Phenolic acids are interesting of their protective role against oxidative damage diseases (coronary heart disease, stroke, and cancers). One of possible sources of flavonoids and phenolic acids – Canadian thick-trefoil (showy trefoil) – Desmodium canadense (L) DC. This plant is not researched as good as many other plants, but there are some works on it. In Lithuania, KUM, there were some research works on Desmodium canadense (L.) DC. There was performed analysis of grass, collected in different phase of vegetation. Also was researched influence of mineral fertilising to amounts of flavonoids and phenolic acids.
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Gaivelytė, Kristina. "Šermukšnio (Sorbus L.) genties augalų fenolinių junginių tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140904_150010-61599.
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Sorbus L. gentis yra plačiai paplitusi pasaulyje. Šermukšnio genties augalų augalinės žaliavos fitocheminė sudėtis tiriama pasaulio mokslininkų, tačiau duomenys apie galimą fenolinių junginių įvairavimą yra nepakankami. Siekiant ištirti Lietuvoje natūraliai augančių ir auginamų kolekcijose šermukšnių (Sorbus L.) rūšių ir veislių lapų, žiedų ir vaisių flavonoidų ir fenolinių rūgščių kokybinės ir kiekinės sudėties įvairavimą, optimizuota efektyviosios skysčių chromatografijos (ESC) metodika. Ištirta paprastųjų šermukšnių (S. aucuparia L.) lapų, žiedų ir vaisių ėminių flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis bei nustatyti įvairavimo ypatumai augalo vegetacijos periodo metu. Ištirta Lietuvoje natūraliose augavietėse augančių S. aucuparia L. lapų ėminių flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis. Nustatyta kolekcijose auginamų Sorbus L. genties rūšių ir veislių augalų flavonoidų ir fenolinių rūgščių kokybinė ir kiekinė sudėtis bei jų kaupimosi dėsningumai. Atlikti Sorbus L. genties rūšių ir veislių vaisių fenolinių junginių antioksidacinio aktyvumo tyrimai taikant pokolonėlinės reakcijos metodą, nustatytas ryšys tarp fenolinių junginių kiekio šermukšnių vaisiuose ir antioksidacinio aktyvumo.Sorbus L. genus is widespread in the world. In the course of research carried out in various countries, analysis of the phytochemical composition of Sorbus L. species has been performed, however, information about possible variation of phenolic compounds is insufficient. In order to investigate qualitative and quantitative composition of phenolic acids and flavonoids in leaves, inflorescences and fruits of Sorbus L. growing in natural habitats and grown in collection in Lithuania HPLC method was developed. Variation patterns of the contents of phenolic compounds flavonoids in leaves, inflorescences and fruits of S. aucuparia L. during the growth season were determined. Qualitative and quantitative composition of phenolic acids and flavonoids in leaves of S. aucuparia L. growing in natural habitats in Lithuania was investigated. Qualitative and quantitative composition of phenolic acids and flavonoids of species and varieties of genus Sorbus L. plants, grown in collections, was investigated. Antioxidant activity of fruits of species and varieties of genus Sorbus L. was investigated applying postcolumn HPLC method and relationship between the amount of phenolic compounds and antioxidant activity was revealed.
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Lima, Fabíola Aliaga de 1984. "Estudo da biotransformação da farinha de centeio por tratamento enzimático e avaliação da bioacessibilidade de ácidos fenólicos pelo modelo de digestão 'in vitro' e de absorção por células intestinais Caco-2." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256639.
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Orientador: Gabriela Alves MacedoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Os ácidos fenólicos possuem propriedades biológicas que desempenham ação antioxidante, anti-inflamatória, antiproliferativa e antimicrobiana. Porém, esses fenólicos de cereais integrais podem ser difíceis de serem absorvidos totalmente pelo organismo, pois estão ligados a outros componentes da parede celular do vegetal ou a um antinutriente (taninos). O zinco, ferro e fósforo de grãos integrais são importantes para o desenvolvimento e manutenção do organismo. No entanto, os cereais ricos em fitato podem apresentar esses minerais complexados ao antinutriente e se tornarem indisponíveis para a absorção. Uma alternativa para melhorar a disponibilidade de ácidos fenólicos e minerais de cereais integrais é o tratamento enzimático. A tanase, tanino acil hidrolase (EC 3.1.1.20), é uma enzima com habilidade de atuar em ligações éster e depsídicas de taninos hidrolisáveis e já foi descrita como capaz de hidrolisar outros fenólicos como ácido tânico, ácido clorogênico, epigalocatequina, dentre outros. A fitase microbiana atua na desfitinização de cereais ricos em fitatos e sua ação melhora a bioacessibilidade de ferro e zinco na formulação infantil. A bioacessibilidade é uma alternativa aos ensaios 'in vivo' que apresentam alto custo de experimental, e pode ser medida pelo modelo de digestão 'in vitro'/absorção pelas células Caco-2. O objetivo deste trabalho foi verificar o efeito de tanase de 'Paecilomyces variotii' e fitase comercial, adicionadas à farinha de centeio, quanto ao teor de fenólicos totais e à identificação e quantificação por CLAE-DAD dos ácidos fenólicos; à capacidade antioxidante (DPPH, ORAC e FRAP); à disponibilidade de minerais (zinco e ferro); ao teor de antinutrientes (tanino hidrolisável e fitato); e à bioacessibilidade dos ácidos fenólicos da farinha. A tanase adicionada à farinha foi capaz de reduzir o teor de tanino hidrolisável, aumentar os fenólicos totais e potencializar a capacidade antioxidante. A farinha tratada com fitase apresentou menor teor de fitato e aumento no conteúdo de fósforo inorgânico proveniente da degradação enzimática. A disponibilidade de zinco e ferro, medida pela razão molar entre os minerais e o fitato foi melhorada após o tratamento da farinha com fitase. Foram identificados os ácidos ferúlico, sinápico e vanílico da farinha de centeio, que após o tratamento com a tanase apresentou aumento no teor de ácido ferúlico em cinco vezes em relação à farinha não tratada. Esse resultado evidencia a ação inédita da tanase de 'P. variotii' como possível feruloil esterase. A farinha biotransformada com tanase apresentou maior teor dos ácidos vanílico, ferúlico e sinápico, porém ao se avaliar a bioacessibilidade houve menor eficiência de transporte desses ácidos quando comparada à farinha controle. Provavelmente, a farinha biotransformada apresentou saturação desses fenólicos sobre a porção apical das células Caco-2 que reduziu a capacidade do transportador de ácidos monocarboxílicos (MCT1) nas duas horas de incubação. Isso corrobora com os resultados obtidos da exposição das células Caco-2 aos padrões de ácidos ferúlico e vanílico na concentração de 50 µl.ml-1 que apresentaram inibição da expressão gênica do MCT1. Contudo, o uso de enzimas como fitase e tanase na farinha de centeio é interessante, pois potencializa sua ação antioxidante, aumenta o teor de fenólicos, aumenta a disponibilidade de zinco e ferro, aumenta o conteúdo de fósforo e reduz os antinutrientes. Para trabalhos futuros seria relevante estudar o tempo de residência de ácidos fenólicos da farinha de centeio no ensaio de transporte celular, pois duas horas de incubação pode ter sido insuficiente para verificar todo o potencial da farinha tratada com tanase
Abstract: Phenolic acids have biological properties that perform antioxidant, anti-inflammatory, antiproliferative and antimicrobial. However, these phenolic of whole grains may be difficult to be completely absorbed by the body because they are connected to other cell wall components of plant or an antinutrient (tannins). Zinc, iron and phosphorus of whole grains are important for the development and maintenance of the organism. However, cereals rich in phytate may have these minerals complexed to antinutrient and become unavailable for absorption. An alternative to improve the availability of phenolic acids and minerals of whole grains is the enzymatic treatment. Tannase, tannin acyl hydrolase (EC 3.1.1.20) is an enzyme with the ability to act on ester bonds and depside bonds of hydrolysable tannins and has been described as capable of hydrolyzing tannic acid, chlorogenic acid, epigallocatechin, among others. Microbial phytase acts on dephytinization of cereals rich in phytate and its action improves the bioaccessibility of iron and zinc in infant formulation. Bioaccessibility is an alternative to in vivo tests that has expensive experimental cost, and can be measured by 'in vitro' model of digestion / absorption by the Caco-2 cells. The aim of this study was to investigate the effect of tannase Paecilomyces variotii and of commercial phytase added to rye flour, as to the total phenolic content and the identification and quantification by HPLC-DAD of phenolic acids; to the antioxidant capacity (DPPH, ORAC and FRAP); to the availability of minerals (zinc and iron); to the antinutrients content (phytate and hydrolyzable tannin); and as to bioaccessibility of phenolic acids of the flour. Tannase added to flour was able to reduce the hydrolyzable tannin content, increase total phenolic and enhance the antioxidant capacity. Flour rye treated with phytase decreased phytate content and increased content of inorganic phosphorus from enzymatic degradation. Availability of zinc and iron of the flour after treatment with phytase was improved, it was measured by the molar ratio between the mineral and phytate. Acids ferulic, sinapic and vanillic were identified and quantified of the rye flour, which after treatment with tannase showed an increase in ferulic acid content in five times bigger that the untreated flour. This result shows the tanase being an original action of 'P. variotii' as possible feruloyl esterase. Biotransformed flour rye with tannase showed a higher content of vanillic acid, ferulic and sinapic, however, when assessing the bioaccessibility was lower transport efficiency of these acids when compared to the control flour. Probably the biotransformed flour showed saturation of these phenolics about the apical portion of Caco-2 cells, they reduced the capacity of the monocarboxylic acids transporter (MCT1) within two hours of incubation. This corroborates the results of exposure of Caco-2 cells to standards of ferulic acid and vanillic at concentration of 50 ?l.mL-1, that showed inhibition of gene expression MCT1. However, the use of enzymes such as phytase and tannase in rye flour is interesting because it enhances antioxidant capacity, it phenolic content is incremented, availability of zinc and iron is bettered, increases the phosphorus content and reduces antinutrients. For further work, would be relevant the study of the residence time of the phenolic acids of rye flour on the cell transport assay, since two hours of incubation may have been insufficient to verify the full potential of flour treated with tannase
Doutorado
Ciência de Alimentos
Doutora em Ciência de Alimentos
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Vaitūnaitytė, Malvina. "Fenolinių junginių kokybinės ir kiekybinės sudėties įvairavimo šermukšnių (S. aucuparia l.) lapuose ir žieduose tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140630_134222-34665.
Full textAbstract:
Tyrimo objektas ir metodai: Sorbus L. genties augalo S. aucuparia L. lapų ir žiedų tyrimas. Bendras fenolinių junginių kiekis paprastojo šermukšnio augalinėse žaliavose nustatytas UV spektrofotometriniu metodu, fenolinės rūgštys ir flavonoidai nustatyti ESC metodu.
Darbo tikslas: nustatyti S. aucuparia L. lapuose ir žieduose esančius fenolinius junginius, jų kiekinės sudėties įvairavimą augalo vegetacijos metu ir augalinių žaliavų (lapų ir žiedų) laikymo metu.
Darbo uždaviniai: Surinkti ir susisteminti literatūros duomenis apie Sorbus aucuparia L., paprastojo šermukšnio augalinių žaliavų cheminę sudėtį, fenolinių junginių analizės metodus, poveikį ir panaudojimą medicinos praktikoje; Ištirti S. aucuparia L. lapų ir žiedų kiekybinę fenolinių junginių sudėtį ir nustatyti bendro fenolinių junginių kiekio įvairavimą augalo vegetacijos metu; Ištirti S. aucuparia L. lapų ir žiedų kokybinę ir kiekybinę fenolinių rūgščių ir flavonoidų sudėtį ir nustatyti jų kiekinės sudėties kitimą augalų vegetacijos periodo metu; Nustatyti S. aucuparia L. lapuose ir žieduose esančių fenolinių junginių kiekybinės sudėties kitimus augalinių žaliavų laikymo metu.
Išvados: S. aucuparia L. augalinės žaliavos gali būti kaip šaltinis išskiriant biologiškai aktyvius junginius, kurie gali būti naudojami medicinos praktikoje. S. aucuparia L. lapuose ir žieduose esančių junginių kiekis kinta augalo vegetacijos metu; lapuose daugiausia fenolinių junginių sukaupiama gegužės - birželio mėn., žieduose – žydėjimo... [toliau žr. visą tekstą]Object and methods: Sorbus aucuparia L. leaves and flowers study. Total amaunt of phenolic compounds in mountain ash leaves and flowers were evaluated using UV spectrophotometry, phenolic acids and flavonoids were identified and evaluated using HPLC. Aim: to identify and evaluate the content of phenolic compounds in rowan leaves and flowers during mountain ash vegetation and during plant materials (leaves and flowers) storage. Objective: to collect and organise the information about the use of Sorbus aucuparia L., S. aucuparia L. leaves and flowers acumulated compounds, phenolic compounds analysis methods and the impact of the use in medical practice; to perform quantitative analysis of S. aucuparia L. leaves and flowers phenolic compounds and to determine the total phenolics content during rowan growing season; to perform qualitative and quantitative analysis of S. aucuparia L. leaves and flowers phenolic acids and flavonoids and to determine the variation of the phenolics content during rowan growing season; to determine phenolic compounds content changes in Sorbus aucuparia L. plant materials (flowers and leaves) during them storage. Conclusions: S. aucuparia L. leaves and flower is a source of biological active substances which can be used in medicinal practice. Phenolic compounds content in S. aucuparia L. leaves and flowers change during vegetation; mainly phenolic compounds in leaves was accumulated in May - June, in flowers - in the beginning of flowering and massive... [to full text]
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Oliveira, Daniela Moura de. "Estudo de biodisponibilidade de compostos fenólicos do chá mate (Ilex paraguariensis)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-23052013-102833/.
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Introdução: O estudo da ação biológica de compostos bioativos e de nutrientes, a fim de que se possa explicar a relação entre o consumo de alimentos e a redução do risco de doenças, é uma das áreas que tem aplicação direta com a saúde pública. A erva mate (Ilex paraguariensis) é uma planta rica em compostos fenólicos (ácidos clorogênicos), extensivamente metabolizados após a ingestão. O conhecimento detalhado sobre os compostos formados pela metabolização dos mesmos, concentrações e tecidos-alvo é fundamental para o completo esclarecimento sobre os mecanismos de ação envolvidos. Objetivo: Avaliar a biotransformação dos ácidos fenólicos do chá mate in vivo em ratos Wistar. Métodos: Os animais foram eutanasiados 90 min (ensaio piloto) ou 30, 60, 120, 240 e 480 minutos (ensaio principal) após a administração de chá mate ou padrão de ácido 5-cafeoilquínico (5CQA) por gavagem. O grupo Controle recebeu solução salina. No ensaio piloto foram analisados plasma, fígado, rins, músculo, estômago e intestino delgado para identificação dos compostos fenólicos e com base nos resultados definida a dose de 2g de chá mate solúvel/kg de peso do animal para ser usada no ensaio principal, que corresponde a 240 mg de fenólicos totais/kg peso, dose administrada ao grupo Padrão na forma de 5-CQA. Quantificação dos compostos fenólicos foi realizada no plasma, fígado, estômago, intestino grosso e urina dos animais do ensaio principal. As análises foram realizadas por UPLC/DAD-MS, após desenvolvimento e validação das metodologias para extração e análise dos ácidos fenólicos nas amostras. O chá mate foi avaliado quanto ao perfil e teor de compostos fenólicos por UPLC/DADMS. Resultados: As metodologias desenvolvidas para extração e análise dos ácidos fenólicos nas amostras biológicas apresentaram bons níveis de recuperação e precisão. Os limites de detecção e quantificação foram determinados para cada fluido/tecido. No ensaio piloto, foram detectados ácidos clorogênicos intactos em todas as amostras, assim como uma série de metabólitos de fase I e II. No ensaio principal, os ácidos clorogênicos livres foram os principais ácidos fenólicos presentes no estômago e intestino grosso, enquanto no plasma, fígado e urina os compostos mais abundantes eram os metabólitos, em ambos os grupos, em especial o ácido caféico ligado ao ácido glicurônico/grupos sulfato e o ácido 3hidroxifenilpropiônico (livre) no grupo Erva Mate e os ácidos feruloilquínicos (FQAas) e ácido 3-hidrofenilpropiônico no grupo Padrão. Demonstrou-se que a absorção e metabolização dos ácidos clorogênicos começa no estômago, mas a maior parte é absorvida no intestino grosso, especialmente após metabolização por bactérias. Cerca de 4,0 por cento dos compostos ingeridos pelo grupo Erva Mate e 3,3 por cento pelo grupo Padrão (mol/mol) estavam presentes na urina na forma de ácidos clorogênicos e dos metabólitos avaliados, 8 hs após a gavagem. Conclusão: A absorção e metabolização dos ácidos clorogênicos começa no estômago. Houve diferenças no tipo e quantidade dos diferentes compostos formados a partir dos fenólicos do chá mate e do 5-CQA puro, demonstrando que o perfil de ácidos clorogênicos presentes no alimento influencia qualitativamente e quantitativamente os metabólitos formados. Maior ênfase deve ser dada aos metabólitos em estudos que avaliem as propriedades biológicas e mecanismos de ação dos compostos fenólicos da erva mate e outros alimentos fonteIntroduction: Evaluation of biological properties of bioactive compounds and nutrients, aiming to explain the relationship between food consumption and decreased risk of diseases, is a field of study directly related to public health. Yerba maté (Ilex paraguariensis) is a plant rich in phenolic compounds (chlorogenic acids) which are extensively metabolized after ingestion. Detailed knowledge about the metabolites, its concentrations and target tissues is fundamental to clarify the action mechanisms involved in disease prevention. Objective: Evaluating the biotransformation of Yerba maté phenolic acids in vivo in Wistar rats. Methods: Animals were euthanized 90 min (pilot study) or 30, 60, 120, 240 and 480 (main study) after administration of maté tea or 5-caffeoylquinic acid (standard) by gavage. Control group received saline solution. In the pilot study plasma, liver, kidneys, muscle, stomach and small intestine were analyzed for identification of phenolic compounds and the dose of 2 g maté tea/kg body weight was defined for the main study, which corresponds to 240 mg of total phenolic compounds/kg bw, dose administered to the Standard group as 5-CQA. Quantification was performed in plasma, liver, stomach, large intestine and urine in the main study. Analyses were performed using UPLC/DAD-MS, after development and validation of methodologies for extraction of phenolic acids from fluids and tissues. Maté tea phenolic compounds amount and profile were evaluated by UPLC/DAD-MS. Results: Developed methodologies showed good levels of recovery and precision. Limits of quantification (LQ) and detection (LD) were calculated for each biological matrix. In the pilot study, chlorogenic acids and their phase I and II metabolites were detected in all biological matrices. In the main study, the main compounds in gastric large and intestinal tissues were intact chologenic acids, whereas in plasma, liver and urine their metabolites were present in larger quantities, specially caffeic acid, bound to glucuronic acid and/or sulfate groups, and 3-hydroxyphenylpropionic acid in the free form on Yerba Mate group, and 3-hydroxyphenylpropionic acid and feruloylquinic acid on the group that received 5-CQA. It was demonstrated that chlorogenic acids absorption and metabolism begins in stomach, but most of the absorption takes place in the large intestine, especially after microbial metabolization. Approximately 4,0 per cent of compounds ingested by Yerba Mate group and 3,3 per cent by Standard group (mol/mol) were recovered in urine collected up to 8 hs after the gavage, in the form of chlorogenic acids and the evaluated metabolites. Conclusion: The absorption and metabolization of chlorogenic acids begins in the stomach. There were differences in the amount and type of compounds formed from maté tea or pure 5-CQA, showing that the profile of chlorogenic acids on food products may influences qualitatively and quantitatively the metabolites formed on the body. Greater emphasis should be given to metabolites in studies that assess biological properties and mechanisms of action of phenolic compounds from yerba mate and other food source
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Jelena, Pejin. "Ispitivanje sadržaja i antioksidativne aktivnosti fenolnih kiselina u toku proizvodnje slada i piva." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2009. https://www.cris.uns.ac.rs/record.jsf?recordId=71284&source=NDLTD&language=en.
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Cilj istraživanja doktorske disertacije je bio da se ukonitnuitetu ispita sadržaj ukupnih fenola, fenolnih kiselina ianitoksidativna aktivnost (antiradikalska aktivnost na DPPH ihidroksil radikale) u toku proizvodnje slada i piva (u ječmu,namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenojsladovini, sladovini tokom fermentacija, mladom pivu i pivu)proizvedenih od tri priznate sorte pivskog ječma: NS 525, NS565 i NS 583.Sadržaj ukupnih fenola u uzorcima ječma je bio: NS 525 -0,76; NS 565 - 0,75 i NS 583 - 0,70 mg GAE/g suve materije.Sadržaj ukupnih fenola u svim proizvednim sladovima (0,96;0,94 i 0,91 mg GAE/g suve materije za NS 525; NS 565 i NS583) je bio viši od sadržaja u ječmu. Sorta NS 525 je imalanajviši sadržaj ukupnih fenola tokom svih faza sladovanja, doksu sorte NS 565 i NS 583 imale niže sadržaje ukupnih fenola.Najniži sadržaj ukupnih fenola imala je sorta NS 583.U svim ispitivanim sortama ječma ferulna, p-kumarinska ivanilinska kiselina su bile dominantne u uzorcima ječma,tokom sladovanja i u proizvedenom sladu.Sadržaj ukupnih fenolnih kiselina u ječmu je iznosio za sortuNS 525 - 200,98; NS 565 - 184,10 i za NS 583 – 177,27 μg/g suvematerije. Sadržaj ukupnih fenolnih kiselina je rastao kod svihispitivanih sorti tokom močenja i dostigao maksimum u tokuprvog dana klijanja za NS 525 – 548,31; NS 565 – 518,65 i NS583 – 517,17 μg/g suve materije. Dobijeni rezultati su pokazalida je proces sladovanja imao značajan uticaj na sadržajpojedinačnih i ukupnih fenolnih kiselina.Sorta NS 525 je imala najvišu antiradikalsku aktivnost naDPPH radikale (EC50 za NS 525 - 0,658; NS 565 - 0,667 i NS583 - 0,758 mg/ml) što pokazuje da sorta ječma ima uticaja naantiradikalsku aktivnost na DPPH radikale. Za ispitivane sorteječma, antiradikalska aktivnost na DPPH radikale se povisilaznačajno tokom močenja. U proizvedenim sladovimaantiradikalska aktivnost na DPPH radikale bila je viša nego uječmu. Trend porasta i smanjenja antiradikalske aktivnosti naDPPH radikale tokom sladovanja je bio isti za sve ispitivanesorte ječma.Antiradikalska aktivnost na hidroksil radikale, izražena kaoEC50 vrednost, u ispitivanim sortama ječma je iznosila: NS 525– 0,352; NS 565 – 0,385 i NS 583 – 0,455 mg/ml. Može sezaključiti da je sorta NS 525 imala najvišu antiradikalskuaktivnost na hidroksil radikale. Antiradikalska aktivnost nahidroksil radikale se znatno povisila tokom močenja. Uproizvedenom sladu je antiradikalska aktivnost na hidroksilradikale bila viša nego u ječmu. Trend porasta i smanjenjaantiradikalske aktivnosti na hidroksil radikale tokomsladovanja je bio isti za sve ispitivane sorte ječma.Sorta NS 525 je imala najviši sadržaj ukupnih fenola kao inajvišu antioksidativnu aktivnost tj. DPPH i hidroksilantiradikalsku aktivnost. Ovi rezultati pokazuju da sortaječma može da utiče na antiradikalske osobine slada. Sorta NS525 je imala najviši sadržaj ukupnih fenola, ukupnih fenolnihkiselina i najvišu antiradikalsku aktivnost na DPPH i hidroksilradikale u toku sladovanja.U svim proizvedenim sladovinama, ohmeljenim sladovinama ipivima, ferulna, p-kumarinska, vanilinska i sinapinska kiselinasu imale najviše sadržaje. Sadržaj svih ispitivanih fenolnihkiselina je povišen nakon hmeljenja. Najviši ukupni sadržajfenolnih kiselina je odreñen u ohmeljenim sladovinama (NS525 - 461,41, NS 565 - 426,22 i NS 583 - 423,56 μg/100ml).Sadržaj ukupnih fenolnih kiselina je u svim proizvedenimpivima bio niži u odnosu na odgovarajuće ohmeljene sladovine.U sladovini proizvedenoj iz slada NS 525 je odreñena najvišaantiradikalska aktivnost na DPPH i hidroksil radikale štoukazuje da antiradikalska aktivnosti komponenti slada imauticaja na antiradikalsku aktivnost proizvedene sladovine. Uispitivanim sladovinama, nakon hmeljenja se znatno povisilaantiradikalska aktivnost na DPPH i hidroksil radikale.Antiradikalska aktivnost na DPPH i hidroksil radikale sesmanjila tokom glavne i naknadne fermentacije.U sladovini proizvedenoj od slada NS 525 sa najvišimsadržajem ukupnih fenola i ukupnih fenolnih kiselinaodreñena je najviša antiradikalska aktivnost na DPPH ihidroksil radikale. Tokom proizvodnje piva sadržaj ukupnihfenola se blago smanjio, što ukazuje da je proces proizvodnjeimao uticaja na njihov sadržaj. Trend smanjenjaantiradikalske aktivnosti na DPPH i hidroksil radikaleodgovara smanjenju sadržaja ukupnih fenola i ukupnihfenolnih kiselina tokom procesa proizvodnje piva.Primenjena GC-MS metoda za odreñivanje sadržaja fenolnihkiselina tokom procesa proizvodnje slada i piva se pokazalakao osetljiva, specifična i dobre ponovljivosti. Može seprimeniti za odreñivanje sadržaja fenolnih kiselina u ječmu,namočenom ječmu, zelenom sladu, sladu, sladovini, ohmeljenojsladovini, tokom fermentacije i u pivu.Sadržaj ukupnih fenola, fenolnih kiselina i antioksidativnaaktivnost slada, koji se koristi za proizvodnju piva, imajuznačajan uticaj na antioksidativnu aktivnost piva.Razumevanje promena sadržaja fenolnih kiselina iantioksidativne aktivnosti tokom proizvodnje slada i piva moženam pružiti vredne informacije o zaštiti endogenihantioksidanata u proizvodnji piva. Na taj način mogu seproizvoditi piva sa višom antioksidativnom aktivnošću i prematome i povišenom otpornošću prema lipidnoj oksidaciji istarenju piva.Studies carried out in the frame of the doctorial thesisaimed at continuous determination of the content oftotal phenolics, phenolic acids and antioxidant activity(antiradical activity on DPPH and hydroxyl radicals)during malt and beer production (in barley, steepedbarley, green malt, malt, wort, hopped wort,fermenting wort, green beer, and beer) produced fromthree accepted brewer’s barley varieties: NS 525, NS565, and NS 583.The total phenolics content in the barley samples was0.76 for NS 525, 0.75 for NS 565 and 0.70 mg GAE/gdry matter (d.m.) for NS 583. Higher content of totalphenolics was determined in the malt samples incomparison with the barley samples: (0.96, 0.94, and0.91 mg GAE/g d.m. for NS 525, NS 565, and NS 583,respectively). Variety NS 525 was the highest in totalphenolics content during all stages of malting whencompared to the other varieties. The lowest content oftotal phenolics was found in the variety NS 583.In all examined samples, ferulic, p-coumaric andvanillic acid dominated in the barley samples, duringmalting and in the produced malts.Content of total phenolic acids in the barley sampleswas 200.98 for NS 525, 184.10 for NS 565 and 177.27mg/g d.m. for NS 583. During steeping, the content oftotal phenolic acids increased for all samples reachingthe maximum at the first day of germination (NS 525 –548.31; NS 565 – 518.65, and NS 583 – 517.17 μg/gd.m.). The obtained results revealed that the maltingprocess had significant impact on the content of totaland individual phenolic acids.Variety NS 525 showed the highest antiradical activityon DPPH radicals (EC50 for NS 525 was 0.658, for NS565 0.667, and for NS 583 0.758 mg/ml) indicating thatbarley variety influences the antiradical activity onDPPH radicals. Antiradical activity on DPPH radicalssignificantly increased during steeping for allinvestigated barley varieties. Higher antiradicalactivity on DPPH radicals was determined inproduced malts when compared to correspondingbarley varieties. Similar increasing and decreasingtrends in the antiradical activity on DPPH radicalsduring malting were observed in all investigatedbarley varieties.The antiradical activity on hydroxyl radicals,expressed as EC50 value, in investigated barleyvarieties, was: 0.325 for NS 525, 0.385 for NS 565, and0.455 mg/ml for NS 583. It can be concluded thatbarley variety NS 525 showed the highest antiradicalactivity on hydroxyl radicals. The antiradical activityon hydroxyl radicals significantly increased duringsteeping. Higher antiradical activity on hydroxylradicals was determined in produced malts whencompared to corresponding barley varieties. Similarincreasing and decreasing trends in the antiradicalactivity on hydroxyl radicals during malting wereobserved in all investigated samples.Variety NS 525 had the highest content of totalphenolics and exhibited the highest antioxidantactivity that is antiradical activity on DPPH andhydroxyl radicals. These results suggest that varietycan influence the malt antiradical properties. VarietyNS 525 was the highest in total phenolics content, totalphenolic acids content and antiradical activity onDPPH and hydroxyl radicals during malting.The highest contents of ferulic, p-coumaric, vanillic,and sinapic acids were determined in all wort, hoppedwort and beer samples. Increased contents of allphenolic acids were observed after hopping. Thehighest content of total phenolic acids was determinedin the hopped worts (461.41 for NS 525, 426.22 for NS565, and 423.56 μg/100 ml for NS 583. The beerscontained less total phenolic acids when compared tothe corresponding hopped worts.Wort produced from NS 525 malt showed the highestantiradical activity on DPPH and hydroxyl radicalswhich indicates that the antiradical activity of maltcomponents affects the antiradical activity in producedwort. After hopping, antiradical activity on DPPH andhydroxyl radicals significantly increased in all worts.The antiradical activity on DPPH and hydroxylradicals decreased during primary and secondaryfermentation.Wort produced from NS 525 malt contained thehighest total phenolic content, total phenolic acidscontent and showed the highest antiradical activity onDPPH and hydroxyl radicals. During beer production,content of total phenolic compounds slightly decreasedwhich indicates that production process had aninfluence on their content. Similar decreasing trendsbetween the antiradical activity on DPPH andhydroxyl radicals and the contents of total phenolicsand total phenolic acids during beer production wereobserved.The applied GC-MS method for determination ofphenolic acids contents during malt and beerproduction was sensitive, specific and had goodrepeatability. It can be used for determination ofphenolic acids content in barley, steeped barley, greenmalt, malt, wort, hopped wort, during fermentationand in beer.The content of total phenolics, phenolic acids andantioxidant activity of malt used for beer productionhave significant influence on the beer antioxidantactivity. Understanding how the phenolic acids andantioxidant activity change during malt and beerproduction can provide valuable information aboutthe protection of endogenous antioxidants in beerproduction. In this way, the production of beer withenhanced antioxidant activity is possible and thereforehigher resistance to lipid oxidation and longer shelflifecould be introduced.
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Dagmey, Aurélien. "Enrichissement d’huiles alimentaires riches en acides gras polyinsaturés, par des composés phénoliques d’origine naturelle, afin de les protéger de la peroxydation lipidique, en vue d’une encapsulation pour augmenter la durée de conservation de ces huiles." Thesis, Compiègne, 2020. http://bibliotheque.utc.fr/EXPLOITATION/doc/IFD/2020COMP2553.
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Les acides linoléique (LA) et α-linolénique (ALA) sont deux acides gras polyinsaturés. Ils sont indispensables à l’Homme car nous sommes incapables de les synthétiser in situ. Ces deux acides gras sont les représentants des oméga-6 (LA) et oméga-3 (ALA). Bien qu’ils soient indispensables et donc nécessaires, l’enjeu du ratio oméga-6/oméga-3 entre ces deux familles est également important à prendre en compte dans l’alimentation. Les habitudes de consommation des Français, ces trente dernières années, ont fait évoluer la balance en défaveur des oméga-3 par rapport aux oméga-6. Or un rééquilibre de la balance oméga-6/oméga-3 tend à diminuer les risques cardiovasculaires. Les huiles de lin et de cameline sont des cultures endémiques en France extrêmement riches en ALA. Elles sont les plus adaptées à une complémentation en oméga-3 d’origine végétale. Cependant, les hautes teneurs en acides gras polyinsaturés de ces huiles sont responsables de leurs faibles stabilités oxydatives. La consommation d’huiles ou de graisses oxydées n’est pas recommandée car elle peut apporter des molécules toxiques. Ainsi l’enjeu de ce projet était d’améliorer la durée de conservation d’huiles riches en acides gras polyinsaturés en valorisant les antioxydants extraits des tourteaux obtenus après trituration des graines. Parmi les molécules étudiées, l’acide gallique, l’acide caféique, le gallate de propyle ainsi que les pinorésinol et laricirésinol purifiées du lin ont montré un réel intérêt pour ralentir l’oxydation, tandis que le sécoisolaricirésinol s’est montré inefficaceLinoleic (LA) and α-linolenic (ALA) acids are two polyunsaturated fatty acids. They are essential for humans because we are unable to synthesize them in situ. These two fatty acids are the representatives of omega-6 (LA) and omega-3 (ALA). Although they are essential and therefore necessary, the issue of the omega-6 / omega-3 ratio between these two families is also important to take into account in the diet. The consumption habits of the French over the past thirty years have shifted the balance against omega-3s compared to omega-6s. Or a rebalancing of the omega-6 / omega-3 balance tends to reduce cardiovascular risks. Linseed and camelina oils are endemic crops in France extremely rich in ALA. They are the most suitable for supplementation with omega-3 of plant origin. However, the high contents of polyunsaturated fatty acids in these oils are responsible for their low oxidative stabilities. The consumption of oxidized oils or fats is not recommended because they can contribute toxic molecules. The aim of this project was to improve the shelf life of oils rich in polyunsaturated fatty acids by enhancing the antioxidant extracts of the cakes obtained after crushing the seeds. Among the molecules studied, gallic acid, caffeic acid, propyl gallate as well as pinoresinol and lariciresinol purified from flax showed a real interest in slowing down oxidation, while secoisolariciresinol was ineffective
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Picoli, Junior Gilmar José [UNESP]. "Influência do glyphosate no perfil bioquímico e fisiológico de populações de azevém (Lolium multiflorum) suscetíveis e resistentes ao herbicida." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/135868.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
No Brasil, o azevém (Lolium multiflorum) foi identificado como resistente ao glyphosate se tornando um grande problema em determinadas lavouras. Dessa forma, entender o comportamento a nível bioquímico e fisiológico desta planta daninha são ferramentas que auxiliam num manejo eficiente. Com isso, o objetivo deste trabalho foi comparar o perfil bioquímico e fisiológico de populações de azevém suscetíveis e resistentes ao herbicida glyphosate aplicação do mesmo. Foram realizados quatro estudos em casa-de-vegetação com delineamento experimental inteiramente casualizados com quatro repetições sendo semeadas três populações de azevém (Lolium multiflorum) consideradas como suscetível (S), com suspeita de resistência (R1) e resistente (R2) ao herbicida glyphosate. No primeiro estudo foi obtido o controle aos 21 dias após a aplicação (DAA) e quantificada a massa seca aos 28 DAA das três populações. Os tratamentos foram constituídos da aplicação do herbicida glyphosate composto pelas doses: 0, 135, 270, 540, 1080, 2160, 4320, 8640 g e.a. ha-1. O segundo estudo teve como objetivo determinar a atividade da enzima fenilalanina amônia liase (PAL) nas diferentes populações as 12, 24, 48 e 72 horas após a aplicação (HAA). Os tratamentos foram compostos de duas doses (720 g e.a. ha-1 e 1080 g e.a. ha-1) mais uma testemunha sem aplicação. No terceiro estudo foram realizadas avaliações da fotossíntese nas três populações ao 1, 3, 7 e 28 DAA. As variáveis analisadas foram: taxa de assimilação líquida de CO2, condutância estomática, concentração interna de CO2, transpiração, eficiência do uso da água e eficiência instantânea de carboxilação. Os tratamentos foram compostos de duas doses (720 g e.a. ha-1 e 1080 g e.a. ha-1) mais uma testemunha sem aplicação. O quarto estudo teve o objetivo de quantificar compostos alterados da rota do ácido chiquímico. Para isso, foram utilizados os mesmos tratamentos do primeiro estudo e realizadas coletas das folhas aos 5, 11 e 28 DAA. Os compostos analisados foram: glyphosate, AMPA (ácido aminometilfosfônico), ácido chiquímico, ácido quínico, shiquimato-3-fosfato, os aminoácidos aromáticos fenilalanina, tirosina e triptofano, ácido ferúlico, ácido coumárico e ácido cafeico. Na população considerada resistente, a atividade da enzima fenilalanina amônia liase manteve-se alta após a aplicação do glyphosate. Todas as variáveis fisiológicas foram afetadas após a aplicação do glyphosate nas três populações, porém, R2 foi capaz de se recuperar apresentando valores semelhantes à testemunha. Os níveis de ácido chiquímico e quínico apresentaram padrões semelhantes onde houve aumento para as populações suscetíveis com o aumento da dose do herbicida enquanto que para a resistente os valores se mantiveram semelhantes. Ocorreu aumento dos níveis de shiquimato-3-fosfato para a população R2 se mantendo constante para as suscetíveis. Houve redução dos aminoácidos aromáticos com a aplicação do glyphosate para as populações suscetíveis.
In Brazil, ryegrass (Lolium multiflorum) was identified as resistant to glyphosate becoming a major problem in certain crops. Thus, understanding the behavior of the biochemical and physiological level of this weed are tools that help in efficient management. Thus, the aim of this study was to compare the biochemical and physiological profile of ryegrass populations susceptible and resistant to glyphosate after spray it. Four studies were carried out in greenhouse with experimental design completely randomized with four replications being seeded three populations of ryegrass (Lolium multiflorum) considered as susceptible (S), suspected of having resistance (R1) and resistant (R2) to the herbicide glyphosate. In the first study was measured the control at 21 days after application (DAA) and at 28 DAA, the dry mass the three populations. The treatments consisted of application of the glyphosate composed of doses: 0, 135, 270, 540, 1080, 2160, 4320, 8640 g a.i. ha-1. The second study aimed to determine the phenylalanine ammonia lyase (PAL) activity in different populations at 12, 24, 48 and 72 hours after application (HAA). The treatments consisted of two doses (720 g a.i. ha-1 and 1080 g a.i. ha-1) plus a control without application. In the third study were carried out photosynthesis assessments at three populations at 1, 3, 7 and 28 DAA. The variables analyzed were: CO2 net assimilation rate, stomatal conductance, CO2 internal concentration, transpiration, water use efficiency and instantaneous carboxylation efficiency. The treatments consisted of two doses (720 g a.i. ha-1 and 1080 g a.i. ha-1) plus a control without application. The fourth study aimed to quantify altered compounds of the shikimic acid pathway. For this, the same treatments of the first experiment were used and made collections of leaves at 5, 11, 28 DAA. The compounds analyzed were: glyphosate, AMPA (aminomethylphosphonic acid), shikimic acid, quinic acid, shikimate 3-phosphate, the aromatic amino acids phenylalanine, tyrosine and tryptophan, ferulic acid, coumaric acid and caffeic acid. The phenylalanine ammonia lyase enzyme was not influenced by glyphosate in resitant population. All physiological variables were affected after the application of glyphosate at the three populations, but R2 was able to recover with values similar to the control. The shikimic and quinic acid levels showed similar patterns where, there was an increase for susceptible populations with increasing doses of the herbicide while in resistant, the values remained similar. There was increase in levels of shikimate-3-phosphate to the R2 population, remaining constant for susceptible. There was a reduction of the aromatic amino acids with the application of glyphosate for the susceptible populations.
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Grzegorzewski, Franziska Verfasser], and Lothar [Akademischer Betreuer] [Kroh. "Influence of Non-Thermal Plasma Species on the Structure and Functionality of Isolated and Plant-based 1,4-Benzopyrone Derivatives and Phenolic Acids / Franziska Grzegorzewski. Betreuer: Lothar W. Kroh." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2010. http://d-nb.info/101461970X/34.
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