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1
Bonetti, Sandra J. "Studies on the isolation and biotransformation of pyrrolizidine alkaloids and related bioactive compounds". Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/30244.
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Briars, Sally-Anne. "The calmodulin stimulated ATPase of Zea mays L". Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:afa92f78-633d-4ae5-8cf5-37ac077acab2.
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Maize coleoptile microsomal vesicles showing calmodulin-stimulated ATPase activity were isolated from 4.5 day old dark grown seedlings. Calmodulin-stiirmlated ATPase activity was maximal (8 nmoles min-1 (mg protein)-1) at 0.35 μM, inhibited by orthovanadate (Iso=20 μM), and specific for ATP. Calmodulin affinity chromatography was used to purify this ATPase after solubilisation with Triton X-100. Calmodulin-stimulated ATPase activity was present in the purified fraction, maximal stimulation (340 nmoles min-1 (mg protein)-1) occurring at 0.3 μM calmodulin. After reconstitution into asolectin liposomes, maximal calmodulinstimulated ATPase activity (500 nmoles min-1 (mg protein)-1) occurred at 0.025 μM. Affinity chromatography using buffers containing asolectin produced true basal activities; maximal calmodulin stimulation was at 0.01 μM (100 nmoles min-1 (mg protein)-1). These results suggest that a calmodulin-stimulated ATPase was purified from the microsomal fraction. Inclusion of protease inhibitors (PMSF, chymostatin) during purification and electrophoresis yielded a polypeptide of 140,000 Mr, similar to the Mr of erythrocyte calmodulin-stimulated, calcium-pumping ATPase (CSCPA). Polypeptides of Mr 91,000, 77-69,000, 51,000, and 40,000 were also present. A monospecific polyclonal antibody raised against erythrocyte CSCPA recognised the 140,000 Mr polypeptide from maize, giving strong evidence that maize cells may contain a polypeptide similar to erythrocyte CSCPA. The reaction mechanism of the proposed maize CSCPA was investigated. After purification in the presence of PMSF phosphorylation was present at 140,000 Mr; this turned over rapidly, was sensitive to hydroxylamine, dependent on calcium, inhibited by lanthanum and stimulated by calmodulin. This was consistent with formation of an acyl-phosphate intermediate, indicating that maize CSCPA is a P-type ATPase, having a reaction mechanism similar to that of the erythrocyte CSCPA. A monoclonal antibody (EA6) was raised to maize CSCPA purified without PMSF; this antibody recognised intact maize CSCPA and inhibited calmodulin-stimulated ATPase activity in microsomal fractions. This antibody also bound to other polypeptides present in microsomal and purified fractions, permitting tentative identification of proteolysis products.
3
Mostafa, Wael M. Abdel-Mageed. "Investigations of secondary metabolites from marine organisms". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Online version available for University member only until Sep. 1, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=53365.
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Tan, Lor-Wai. "Biochemical aspects of self-incompatibility in Petunia hybrida". Title page, Contents and Summary only, 1988. http://web4.library.adelaide.edu.au/theses/09A/09at161.pdf.
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King, Douglas Iain. "Kangaroo Island Propolis: Improved Characterisation and Assessment of Chemistry and Botanical Origins through Metabolomics". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17080.
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Introduction: Propolis, a sticky substance produced by bees from plant resins, has a long history of safe use medicinally. Kangaroo Island, SA (KI) lacks many introduced European plants bees preferentially collect resin from; consequentially, propolis from KI is produced from resinous native plants. Several identifiably reproducible pure-source KI propolis types exist. Research into medical use of compounds from KI native plants is limited. Metabolomics is a growing field of interest in natural products chemistry, including beehive products. Metabolomic and similarity-scoring assessment of KI propolis, through statistical evaluation of 1D 1H-NMR fingerprints, provides an entry point for research into medical use of KI native plant compounds. Many avenues to product discovery in pharmaceutical chemistry are suffering diminishing returns: metabolomics-guided natural products assessment has the potential for further identification of novel therapeutic compounds from resinous plants. Aim: To assess and identify, via metabolomic investigation of NMR fingerprints, major propolis types on KI, and to produce, from this, similarity-scoring tools for assessment of propolis samples. Method: KI propolis samples, identified as pure-source by TLC, and resinous KI plants were analysed by 1H-NMR and HPLC. Data points of interest were normalised and binned to form individual sample ‘fingerprints’. Data from these fingerprints were analysed by hierarchical clustering and principal component analysis (PCA) to confirm provisionally-identified pure-source propolis types and identify subtypes within propolis and resinous plant species. From this, calculator tools were created to score similarity (out of 1000) of 1H-NMR fingerprints to the average spectrum of pure-source propolis types, as well as to calculated mixtures of these average spectra. Assessment of the chemistry of two major KI propolis types identified (CP- and F-type) was made by fractionation and NMR, with one compound, 6,8-diprenyleriodictyol, isolated from CP-type propolis in quantity, submitted for epigenetic and other biological assays. Results: Source resinous plants were demonstrated, through hierarchical clustering and PCA, to cluster with propolis types arising from these sources, with closely related plants and sub-chemotypes clustering separately, confirming specificity. A number of previously-identified pure-source propolis types and known botanical sources were shown to have very high similarity (> 800/1000) to the expected propolis type. Calculator tools were observed to accurately predict the content of mixed propolis samples to within ± 10%. A number of methylflavanones, and two novel terminally-hydroxylated prenyldihydrochalcones were isolated from F-type propolis. 6,8-diprenyleriodictyol demonstrated a range of promising activity in biological assays. Conclusion: Metabolomic evaluation of 1H-NMR fingerprints can reliably identify and assess pure-source KI propolis and identify botanical origin of source resins. Similarity scoring calculators can accurately identify mixed-source propolis samples. KI propolis types are a rich source of pharmaceutically-interesting flavanones and related compounds, many of which are prenylated. 6,8-diprenyleriodictyol displays strong anti-inflammatory and anticancer activity, especially against Burkitt’s lymphoma. A number of possible epigenetic pathways for this activity were observed.
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WILSON, HEATHER-ANNE MARIE. "OPTIMIZING THE RELEASE OF BOTANICAL INGREDIENTS FROM ANTIPERSPIRANTS/DEODORANTS". University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1069796149.
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Logie, Catherine Gwynedd. "The pyrrolizidine alkaloids of Senecio chrysocoma and Senecio paniculatus". Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005000.
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In order to compare the pyrrolizidine alkaloid content of two closely related species, Senecio chrysocoma and S. paniculatus, nine populations of plants distributed between the two species, were examined. Three novel pyrrolizidine alkaloids, 7ß-angelyl-l-methylene-8∝-pyrrolizidine, 7ß-angelyl-l-methylene-8∝-pyrrolizidine and 7ß-angelyl-l-methyleneSO!-pyrrolizidine-4-oxide, as well as eight known pyrrolizidine alkaloids, 7-angelylhastanecine, 9-angelylhastanecine, 7-angelylplatynecine, 9-angelylplatynecine, 9-angelylplatynecine-4-oxide, sarracine, neosarracine and retrorsine, were isolated and identified by NMR and GC-MS techniques. Traces of five tiglyl isomers, 9-tiglylplatynecine, 9-tigl ylplatynecine-4-oxide, 7ß-tiglyl-l-methylene-8∝-pyrrolizidine, sarranicine and neosarranicine, were also isolated and tentatively identified; however, these compounds could have been artefacts of the extraction and analytical procedures. While both species of plant investigated, S. chrysocoma and S. paniculatus, were found to be morphologically different, their pyrrolizidine alkaloid content was, in fact, very similar. The presence of retrorsine in S. paniculatus plant extracts, but not in those from S. chrysocoma plants, was the only major chemical difference observed. It is perhaps significant that retrorsine was the only macrocyclic pyrrolizidine to be identified. A comprehensive, computerised database of physical data for pyrrolizidine alkaloids has been compiled, which has facilitated the identification of new pyrrolizidines and the examination of trends in proton and carbon-13 NMR data for pyrrolizidine alkaloids. A stereospecific synthesis of 7ß-angelyl-l-methylene-8∝-pyrrolizidine was undertaken toconfirm the absolute stereochemistry of the product isolated from S. chrysocoma and S. paniculatus. An inseparable 5:2 mixture of 7ß-angelyl-l-methylene-8∝-pyrrolizidine and 7ß-angelyl-l,2-didehydro-l-methyl-8∝-pyrrolizidine, together with a small amount of tiglyl isomer, was finally synthesised. The application of various chiral differentiating chromatographic and spectroscopic techniques confirmed that both the natural and synthetic products had the same stereochemistry, permitting the natural alkaloid to be identified as 7ß-angelyl-methylene-8∝-pyrrol izidine
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Chan, Kwok-yin. "A review on the effects of ginsenoside on cardiovascular diseases and the phytochemistry of ginsenoside extracts from panax notoginseng". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23424886.
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Mousa, Souad Abd. "Photochemistry of β-carbolines and azine dyes in solution and colloidal systems". Thesis, Swansea University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678433.
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Ulbrik, Teresa Yolanda Lustosa. "Cellulolytic fermentation by clostridium thermocellum". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/10027.
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Grue, Margaret Ruth. "A study of the alkaloid content of the Senecio speciosus/Macrocephalus complex". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005027.
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The isolation and identification of pyrrolizidine alkaloids from various plant species from 1988 to May 1991 are reviewed and the alkaloids of two indigenous plant species, Senecio speciosus Willd and Senecio macrocephalus DC, were investigated. A brief review of the methods used for isolation and identification of pyrrolizidines is also given. S. speciosus was found to contain two new alkaloids, 7-senecioyl-9-sarracinylheliotridine and 7-isosarracinyl-9- sarracinyl-heliotridine, which were identified using highfield NMR techniques. A number of other alkaloids were tentatively identified using GC-MS. S. macrocephalus contains very little alkaloid, but a number of pyrrolizidine alkaloids were tentatively identified using GC-MS. Standard alkaloids for GC-MS work were obtained both by extraction from a number of plant species and by synthesis of simple monoester alkaloids. In this process the alkaloid neosarracine, previously described by GC-MS, was isolated and NMR data for this compound are reported for the first time. S. speciosus and S. macrocephalus are morphologically very similar and their counterparts in the Grahamstown district exhibit features characteristic of both species. This could be due to hybridization, genetic mutation or simple variation within the species. The alkaloids of four local plant populations were examined in order to collect taxonomic markers whereby it was hoped that the Grahamstown plants could be satisfactorily classified. Three of the plant populations were found to contain 7-senecioyl-9-sarracinylheliotridine and 7-angelyl-9-sarracinyl-heliotridine. One population was found to contain the known alkaloid retrorsine along with the new alkaloid 2-hydroxy-l, 2-dihydrosenkirkine. The alkaloidal fractions of all four populations were compared using GC-MS and NMR techniques. Tentative taxonomic conclusions were drawn.
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Logie, Malcolme Ronald Ruxton. "Photosynthetic gas exchange responses to light, temperature, carbon dioxide and water stress, and changes in photosynthetic pigments to light and water stress in two cultivars of Hordeum vulgare L". Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1003779.
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The gas exchange responses of two cultivars of Hordeum vulgare L., to light, temperature, CO₂ and water stress were investigated in the laboratory. The optimum temperature for net CO₂ assimilation was found to be 25°C and 22.5°C for cv. Clipper and cv. Dayan respectively. Net CO₂ assimilation was reduced at 30°C in cv. Dayan. At low light intensity the highest quantum yield efficiency was 0.051 mol.mol⁻¹ at 30°C for cv. Clipper, and 0.066 mol.mol⁻¹ at 20°C for cv. Dayan. At the same temperature, cv. Clipper had a higher water use efficiency than cv. Dayan, but stomatal conductance for cv. Dayan was higher than cv. Clipper. Stomatal limitation to CO₂ was lowest at the optimum temperature for CO₂ assimilation in both cultivars. Stomata limited CO₂ assimilation in cv. Clipper to a larger degree than in cv. Dayan. Relative stomatal limitation for cv. Clipper at 25°C was 0.280 ± 0.010, and for cv. Dayan at 22.5°C was 0.028 ± 0.011. Short-term exposure to elevated CO₂ concentrations increased CO₂ assimilation in both cultivars, but more so for cv. Clipper. Transpiration rate at elevated CO₂ partial pressures were higher in cv. Dayan than in cv. Clipper. At very high CO₂ (860 μmol.m⁻²s⁻¹) partial pressure water use efficiency in cv. Clipper was higher than cv. Dayan, but at low CO₂ partial pressures water use efficiency in cv. Dayan was higher than cv. Clipper. Water stress reduced the relative leaf water content and net CO₂ assimilation in both cultivars. Cultivar Dayan was more tolerant to water stress, and CO₂ assimilation in this cultivar was less affected by water stress. In both cultivars water stress increased the concentration of chlorophyll a, chlorophyll b, and chlorophyll a+b. The chlorophyll a:b ratio remained relatively constant throughout the stress period. No correlation between relative leaf water content and total carotenoid concentration was observed.
13
Chen, Zewei. "Authentication of Complex Botanical Materials by Chemometrics and Chemical Profiling". Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1617010785195628.
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Swartz, Vuyiswa Gladys. "Phytochemical studies of Helichrysum patulum". Thesis, University of the Western Cape, 2006. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3651_1189147447.
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Since Helichrysum is known by the indigenous people of Africa for therapeutic properties, such as against colds, flu and wounds, the aim of this study was to focus on the patulum species found predominantly in the Western Cape region of South Africa and by means of isolation and identification of the plant constituents, be able to relate the therapeutic activity on the basis of literature precedents, to the compounds extracted.
15
Burdon, Jeremy N. "The role of ethylene in fruit and petal abscission in the red raspberry (Rubus idaeus L. cv. Glen Clova)". Thesis, University of Stirling, 1987. http://hdl.handle.net/1893/26678.
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Weakening of fruit and petal abscission zones in Rubus idaeus L. cv. Glen Clova was accompanied by increased rates of ethylene production. Both processes were accelerated by a supply of exogenous ethylene. In the ripe fruit natural ethylene levels were saturating. The rise in ethylene production clearly preceded petal abscission but in fruit the increase virtually coincided with the start of weakening. Raspberry fruit of other varieties and blackberries clearly showed the abscission zone weakening could precede any increase in ethylene production. The internal ethylene concentrations of Glen Clova fruit at the mottled stage reached those levels which had to be added to stimulate abscission (ie 0.25 to 0.5 ppm). This is the very stage at which abscission zone weakening was first noticeable. Both fruit and petal abscission was retarded by the application of inhibitors of ethylene production ( AVG, Co 2+) or action (Ag+ ). Likewise a reduction in the internal ethylene under hypobaric pressure also retarded fruit abscission. None of these treatments were totally capable of preventing abscission. In fruit abscission the receptacle appears to have an important role. The increase in receptacle ethylene production precedes that of the drupelets. The enlargement and swelling of the receptacle tissues are important in both abscission zone weakening and ethylene production. This receptacle development may in turn be controlled by the development of fertilised drupelets. The ethylene production in both fruit and petal abscission is limited initially by the supply of ACC. In both cases endogenous ACC levels increase in step with ethylene production. Ethylene's role as a coordinating/accelerating agent in fruit and petal abscission is discussed.
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Owens, Zachary J. "The purification and electrochemistry of his-tagged photosystem II". [Denver, Colo.] : Regis University, 2009. http://165.236.235.140/lib/ZOwens2009.pdf.
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Bartonek-Roxå, Eva. "Recombinant peroxidases and xylanases I. Cloning and production of a peroxidase from horseradish : II. Characterisation of functional domains of thermostable xylanases from Rhodothermus marinus /". Lund : Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/68945038.html.
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Buisson-Provost, Dominique. "Light-activated phytotoxic thiophenes in Flaveria linearis L". FIU Digital Commons, 1990. http://digitalcommons.fiu.edu/etd/1818.
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Chromatographic analyses of crude leaf extracts of Flaveria linearis L. revealed the presence of four acetylenic monothiophenes. Three of these metabolites were purified and structurally characterized by UV, NMR, IR, and GC-MS. Germination, growth, and survival/mortality studies with and without UVA, the activating wavelengths of these metabolites, were conducted with the crude leaf extracts and the purified compounds (taken individually and combined) against selected crop species (lettuce, radish, and carrot).
Results suggest that acetylenic metabolites are phytotoxic against lettuce, carrot, and radish, but with variability in response among species. These variations in sensitivity and the allelopathic potential of F. linearis is discussed.
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陳國賢 i Kwok-yin Chan. "A review on the effects of ginsenoside on cardiovascular diseases and the phytochemistry of ginsenoside extracts from panax notoginseng". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31970382.
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Whitney, Sarah E. C. "The interaction of cellulose with xyloglucan and other glucan-binding polymers". Thesis, University of Stirling, 1996. http://hdl.handle.net/1893/2243.
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This thesis examines the interaction of xyloglucan, the major hemicellulosic component of type I primary plant cell walls, with cellulose. Initial attempts to form xyloglucan-cellulose complexes by in vitro association methods are described, which gave low levels of interaction, with features not similar to those found in primary wall networks. The majority of the work focusses on the use of the bacterium Acetobacter aceti ssp. xylinum (ATCC 53524), which synthesise highly pure, crystalline cellulose as an extracellular polysaccharide. Addition of xyloglucan to a cellulose-synthesising bacterial culture results in the formation of cellulose-xyloglucan networks with ultrastructural and molecular features similar to those of the networks of higher plants. Applicatioon of the bacterial fermentation system is extended to incorporate the polysaccharides glucomannan, galactomannan, xylan, mixed-linkage glucan, pectin and carboxymethylcellulose, all of which impart unique architectural and molecular effects on the composistes formed. Preliminary data on the mechanical properties of composite structures under large and small deformation conditions are also described.
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Sanchez, Rodolfo Marcchiori. "Estudo fitoquímico e propriedades biológicas da Dipteryx alata Vogel (baru) /". Ilha Solteira, 2014. http://hdl.handle.net/11449/123176.
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Orientador: Rosangela da Silva de LaurentizBanca: Jean Richard Dasnoy Marinho
Banca: Lizandra Guidi Magalhães
Resumo: Devido à importância do bioma cerrado, inclusive para a manutenção de outros biomas interligados, nas últimas décadas pesquisadores das mais variadas áreas vêm propondo alternativas de uso das espécies do cerrado como forma de preservar a fauna e flora local. Uma das formas para auxiliar na preservação dessas espécies esta o estudo sobre constituintes fitoquímicos e propriedades medicinais de plantas desse bioma usadas na medicina tradicional. O objetivo desse estudo é a confirmação do potencial terapêutico bem como da toxicidade dessas plantas usadas na medicina tradicional local, bem como estudar o potencial medicinal de plantas ainda não investigadas. A espécie Dipteryx alata Vogel (baru) é uma das espécies nativas do cerrado que apresenta grande potencial nutricional e farmacológico a ser investigado, pois segundo a medicina tradicional ela é utilizada no combate à bronquite, diarreia, disenteria, dor, dor de garganta, gripe, picada de cobra, tosse e como cicatrizante, entretanto, apenas a atividade contra picada de cobra foi cientificamente comprovada. Desta forma, na tentativa de aliar o valor nutricional da polpa dos frutos do baru a um possível efeito terapêutico, foram realizados estudos sobre os fitoconstituintes presentes nesta parte da planta, a fim de guiar estudos sobre as possíveis propriedades biológicas valorizando o fruto como um alimento nutracêutico, em áreas de ocorrência da planta que apresentam elevados índices de doenças negligenciadas. Os resultados dos estudos fitoquímicos mostraram a presença de alcaloides, taninos, flavonoides, glicosídeos cardiotônicos e saponinas em consideráveis concentrações e antraquinonas em baixa concentração. A presença desses fitoconstituintes forneceu suporte para a realização de ensaios para a determinação do potencial antiparasitário. A atividade antimicrobiana também foi avaliada devido ao uso medicinal da planta para infecções do trato ...
Abstract: Due to the importance of the cerrado biome, including the maintenance of other interconnected biomes in recent decade's researchers from different fields have proposed alternative use of the cerrado species as a way to preserve the local fauna and flora. One way to help the preservation of species is the study of the medicinal properties of plants of this biome used in traditional medicine. The objective of these studies is to confirm the therapeutic potential and the toxicity of these plants used in traditional local medicine as well as studying the medicinal potential of plants yet to be investigated. The specie Dipteryx alata Vogel (baru) is a native species of the cerrado with great nutritional and pharmacological potential to be investigated, because according to traditional medicine it is used to combat bronchitis, diarrhea, dysentery, pain, sore throat, flu, snakebite, cough and as cicatrizant, however, only the activity against snakebite has been scientifically proven. Therefore, trying to combine the nutritional value of baru fruits pulp to the potential therapeutic effect, studies on the determination of phytochemicals present were performed to guide studies on possible biological properties valuing the fruit as a nutraceutical food in areas of occurrence of the plant that show high negligible diseases indices. The results of the phytochemical studies showed the presence of alkaloids, tannins, flavonoids, saponins and cardiotonic glycosides in considerable amounts and anthraquinones at low concentration. The presence of these phytochemicals has given support for conducting tests to determine the antiparasitic potential. Antimicrobial activity was also evaluated due to the medicinal use of the plant for the urinary tract infections. In addition, the cytotoxicity of the pulp was also evaluated on LLC- MK 2 cells to support the safe use of the fruit. Antimicrobial assays were performed using the bacterial strains Proteus sp., E. ...
Mestre
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Silva, Marcelo José Dias. "Estudo fitoquímico e biológico dos extratos das folhas de Mimosa caesalpiniifolia Bentham /". Araraquara, 2016. http://hdl.handle.net/11449/139452.
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Orientador: Wagner VilegasCoorientador: Marcelo Aparecido da Silva
Banca: Marcos José Salvador
Banca: Claudia Quintino da Rocha
Banca: Camilo Dias Seabra Pereira
Banca: Douglas Gatte-Picchi
Resumo: Mimosa é um dos maiores gêneros da família Fabaceae e subfamília Mimosaceae, são fontes de alcaloides, ácidos fenólicos, terpenoides, carotenoides e principalmente flavonoides. Apesar da maioria das espécies serem encontradas na Caatinga e Cerrado, principalmente na região nordeste do Brasil, ainda são poucos os estudos químicos e biológicos sobre essas plantas. Por isso, neste trabalho contribuímos no conhecimento a respeito dessa família, investigando as folhas de Mimosa caesalpiniifolia, indicada contra doenças inflamatórias, antimicrobianas e infecções. O extrato foi preparado por percolação com etanol 70% com rendimento em massa de 25%. Em seguida, foi fracionado usando técnicas cromatográficas convencionais. As estruturas foram identificadas por análises espectroscópicas (UPLC-MS; ESI-IT-MSn e RMN de 1H e de 13C). A investigação química levou à identificação de vinte e sete substâncias sendo três flavonoides descritos pela primeira vez na literatura. Na quantificação dos marcadores químicos, em 100,0 mg do extrato hidroalcoólico de Mimosa (EHM), há 0,82 mg de galato de etila (1) e 0,44 mg de cassiaoccidentalina A (21). No ensaio de genotoxicidade, o EHM nas doses de 62,5 e 125 mg/Kg e na fração acetato de etila (Fr-EtOAc) na dose de 62,5 mg/Kg não apresentaram efeitos tóxicos. Os resultados demonstraram que o EHM foi capaz de prevenir lesões oxidativas do DNA nas células do fígado induzidas pelo peróxido de hidrogénio in vitro e diminuição de danos genômicos foi detectada em células de fígado após a exposição à Fr-EtOAc. No ensaio de colite o EHM na dose de 125 mg/Kg apresentou efeito preventivo e a Fr-EtOAc na dose de 50 mg/Kg efeito terapêutico com redução na intensidade das lesões. No ensaio de edema de orelha... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Mimosa is family Fabaceae and subfamily Mimosaceae, are sources of alkaloids, phenolic acids, terpenoids, carotenoids and flavonoids mainly. Although most species are found in Caatinga and Cerrado, especially in northeastern Brazil, there are few chemical and biological studies on these plants. Therefore, this work contribute knowledge about this family, investigating the leaves of Mimosa caesalpiniifolia indicated against inflammatory, antimicrobial and infections. The extracts were prepared by percolation with 70% ethanol to yield 25% mass. Then they were fractionated using conventional chromatographic techniques. The structures were identified by spectroscopic analysis (UPLC-MS, ESI-IT-MSn and 1H NMR and 13C). The chemical research led to the identification of twenty-seven substances with three flavonoids first described in the literature. In quantification of chemical markers in 100.0 mg of the hydroalcoholic extract of Mimosa (EHM), there are 0.82 mg of ethyl gallate (1) and 0.44 mg cassiaoccidentalina A (21). In the genotoxicity test, the EHM at doses of 62.5 and 125 mg/kg and the ethyl acetate fraction (Fr-EtOAc) at a dose of 62.5 mg/kg showed no toxic effects. The results showed that the EHM was able to prevent oxidative DNA damage in liver cells induced by hydrogen peroxide in vitro and decreased DNA damage was detected in liver cells following exposure to Fr-EtOAc. In the EHM colitis test in a dose of 125 mg/kg showed a preventive effect and Fr-EtOAc 50 mg / kg therapeutic effect with a reduction in the intensity of the lesions. In the test ear edema induced by the EHM xylene (125 and 250 mg/kg) significantly inhibited 52% and 64%, respectively, and exhibited 82% antidiarrheal activity induced by castor oil. In the antifungal assay FR-EtOAc showed... (Complete abstract click electronic access below)
Doutor
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Santos, Dayane Graziella Pereira de Oliveira dos 1988. "Produção de biomassa e teor de cumarina em folhas de guaco (Mikania laevigata Sch. Bip. ex Baker) em diferentes idades da planta /". Botucatu, 2016. http://hdl.handle.net/11449/138871.
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Orientador: Lin Chau MingBanca: Alexandra Christine Helena F. Sawaya
Banca: Marcos Roberto Furlan
Resumo: A espécie Mikania laevigata Sch. Bip. ex Baker, popularmente conhecida como guaco, pertence à família Asteraceae, é originária da região sul do Brasil e está entre as plantas medicinais adotadas pelo Sistema Único de Saúde do Brasil. M. laevigata é uma opção agrícola promissora no cultivo das medicinais, estando acessível ao pequeno produtor, tendo em vista a crescente demanda do mercado consumidor brasileiro por fitoterápicos. Uma vez que as plantas medicinais são classificadas como produtos naturais, a lei permite que sejam cultivadas e comercializadas desde que se atinja o padrão de qualidade necessário. O presente trabalho foi instalado e conduzido na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - UNESP, Campus de Botucatu, Estado de São Paulo. O objetivo desta pesquisa foi avaliar a produtividade de biomassa e teor de cumarina do guaco colhido em diferentes idades da planta. Foi observada maior produtividade para as variáveis avaliadas aos onze meses de idade do guaco, obtendo 0,96 t ha-1 de matéria seca de folha sendo que não houve diferença estatística quanto ao teor de cumarina aos 7, 9, e 11 meses de idade de Mikania laevigata. Nas condições em que foi realizada a pesquisa, o maior rendimento de biomassa x teor de cumarina foi obtido aos 11 meses de idade do guaco, o qual possibilitou o melhor resultado para o rendimento extrativo de cumarina em folhas secas.
Abstract: The species Mikania laevigata Sch. Bip. ex Baker, popularly known as guaco, belongs to the Asteraceae family and it is native to southern Brazil it is among the medicinal plants adopted by the Unified Health System in Brazil (SUS). M. laevigata is a promising option in agricultural cultivation of medicinal plants and is accessible to small farmers, in view of the growing demand of the Brazilian market for herbal medicines. Since medicinal plants are classified as natural products, the law allows them to be grown and marketed it they achieve the required quality standards. This work was conducted at the Lageado Experimental Farm, Faculty of Agricultural Sciences - UNESP, Botucatu, State of São Paulo. The objective of this research was to evaluate the productivity of biomass and coumarin content of guaco harvested at different ages of the plant. It was observed higher productivity for the variables evaluated at eleven months of guaco, obtaining 0.96 t ha-1 of dry leaf and there was no statistical difference in the coumarin content at 7, 9, and 11 months of age Mikania laevigata. The conditions under which the survey was conducted, the higher biomass yield x coumarin content of guaco was obtained at 11 months of age, which enabled the best result for the extraction yield of coumarin in dry leaves
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Jones, Sarah Melissa Jane. "Isolation of xylanolytic multi-enzyme complexes from Bacillus subtilis SJ01". Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1004033.
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Cellulose and hemicellulose account for a large portion of the world‘s plant biomass. In nature, these polysaccharides are intertwined forming complex materials that require multiple enzymes to degrade them. Multi-enzyme complexes (MECs) consist of a number of enzymes working in close proximity and synergistically to degrade complex substrates with higher efficiency than individual enzymes. The cellulosome is a cellulolytic MEC produced by anaerobic bacteria that has been studied extensively since its discovery in 1983. The aim of this study was to purify a cellulolytic and/or hemicellulolytic MEC from an aerobic bacterium of the Bacillus genus. Several bacterial isolates were identified using morphological characteristics and 16S rDNA sequencing, and screened for their ability to degrade cellulose and xylan using a MEC. The isolate that produced a high molecular weight protein fraction with the greatest ability to degrade Avicel®, carboxymethyl cellulose (CMC) and birchwood xylan was identified as Bacillus subtilis SJ01. An optimised growth medium, consisting of vitamins, trace elements, birchwood xylan (as the carbon source), and yeast and ammonium sulphate (as the nitrogen sources), increased the production of CMCase and xylanase enzymes from this bacterium. The removal of a competing bacterial strain from the culture and the inhibition of proteases also increased enzyme activities. A growth curve of B. subtilis SJ01 indicated that xylanase production was highest in early stationary growth phase and thus 84 hours was chosen as the best cell harvesting time. To purify the MECs produced by B. subtilis SJ01 size-exclusion chromatography on a Sephacryl S-400 column was used. It was concluded that (for the purposes of this study) the best method of concentrating the culture supernatant prior to loading onto Sephacryl S-400 was the use of ultrafiltration with a 50 kDa cut-off membrane. Two MECs, named C1 and C2 of 371 and 267 kDa, respectively, were purified from the culture supernatant of B. subtilis SJ01. Electrophoretic analysis revealed that these MECs consisted of 16 and 18 subunits, respectively, 4 of which degraded birchwood xylan and 5 of which degraded oat spelt xylan. The MECs degraded xylan substrates (C1: 0.24 U/mg, C2: 0.14 U/mg birchwood xylan) with higher efficiency than cellulose substrates (C1: 0.002 U/mg, C2: 0.01 U/mg CMC), and could therefore be considered xylanosomes. Interestingly, the MECs did not bind to insoluble birchwood xylan or Avicel® and did not contain glycosylated proteins, which are common features of cellulosomes. This study is, therefore, important in revealing the presence of MECs that differ from the cellulosome and that may have particular application in industries requiring high xylanase activity, such as the paper and pulp industry. The abundant genetic information available on B. subtilis means that this organism could also be used for genetic engineering of cellulolytic/hemicellulolytic MECs.
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Tsui, Wing-yan Pamela. "Phytochemical investigation of plants used in traditional medicine in Hong Kong /". Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17594303.
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Gazola, Marcos Bertani. "Caracterização de polpas e bebidas à base de extrato hidrossolúvel de soja, amora, pitanga e mirtilo: análises reológicas, fitoquímicas, físico-químicas, microbiológicas e sensoriais". Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/742.
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A geografia brasileira e suas dimensões continentais tornam o país apto para cultivo e desenvolvimento de diferentes espécies vegetais, ocupando o ranking de terceiro maior produtor mundial de frutas e o segundo de soja. As tendências globais apontam o crescimento do mercado de bebidas não alcoólicas, em particular a base de frutas e extratos hidrossolúveis de soja. Diante destes fatos, este trabalho buscou a caracterização de polpas e bebidas de pitanga (Eugenia uniflora L.), amora (Morus nigra) e mirtilo (Vaccinium spp.), provenientes de plantações comerciais e do bioma Floresta com Araucária na região sudoeste do Paraná, através de análises físico-químicas, microbiológicas, reológicas, fitoquímicas, antimicrobianas e sensorial. Entre as análises físico-químicas de conteúdo mineral, proteínas, sólidos, lipídios e glicídios, o pH e a relação sólidos solúveis totais/acidez titulável total (SS/ATT) foram os descritores que melhor explicaram a diferença entre as polpas e as bebidas (Análise de Componentes Principais). A prospecção de fitoquímicos nos extratos das polpas dos frutos revelou a presença de diversos metabólitos secundários, principalmente flavonas, flavonóis, xantonas e flavanonóis. Os extratos polares apresentaram maior riqueza desses constituintes. Os extratos foram também analisados por meio de infravermelho, possibilitando a observação de que, o etanol 70% é o solvente mais indicado na pesquisa de antioxidantes, em comparação com o éter de petróleo e o éter etílico, por apresentar maior poder de extração de grupamentos polares, bem como pela presença de picos de absorção de O-H em todas as polpas. Não houve diferença estatística (p 0,05) nas capacidades antioxidantes das polpas, contudo o maior teor de fenólicos totais obtido ocorreu na polpa de mirtilo. Os testes de atividade antimicrobiana indicaram poder fungistático da polpa de mirtilo para a levedura Cândida tropicalis, com concentração inibitória mínima de 833,33 μg mL-1. As curvas de escoamento demonstraram comportamento não newtoniano com características pseudoplásticas, com excelente ajuste ao modelo de Ostwald-de-Waele. O efeito da temperatura sobre a viscosidade aparente das polpas foi verificado através de equação do tipo Arrhenius e analisado em relação à energia de ativação, cujo maior valor foi obtido para a polpa de amora. A análise sensorial das bebidas preparadas apontou para aceitação das mesmas perante os provadores, indicando potencial para a industrialização.The Brazilian geography and its continental dimensions make the country suitable for cultivation and growth of different plant species, occupying the ranking of third largest world producer of fruits and the second of soybean. Global trends point to the growing market of non-alcoholic beverages, particularly, the ones with fruits and soybean water extracts base. Before these facts, this research sought the characterization of pulps and beverages of pitanga (Eugenia uniflora L.), mulberry (Morus nigra) and blueberry (Vaccinium spp.), from commercial plantations and the biome Araucaria Forest in the southwest of Parana, through the physico-chemical, microbiological, rheological, phytochemical, anti-microbiological and sensory analysis. Among the physico-chemical analysis of mineral content, protein, solids, lipids and carbohydrates, the pH and the relation total soluble solids/ total tritable acidity (SS/ATT) were the descriptor that best explained the difference between pulps and beverages (Principal Component Analysis). The phytochemical prospection in the extract of the fruits’ pulps revealed the presence of several secondary metabolites, mainly flavones, flavonols, xanthones and flavanonols. The polar extract presented higher richness of these constituents. The extracts were also analyzed through infrared, allowing the observation that ethanol 70% is the most suitable solvent in antioxidants search, compared with petroleum ether and ethyl ether, because of its greater potential for polar groups extraction and the presence of O-H absorption peaks in all pulps. There was not statistic differences (p 0,05) in the antioxidants capacities of the pulps, however, the highest total phenolics obtained occurred in the mulberry pulp. The antimicrobiological activity tests indicated fungus power of the blueberry pulp for the Cândida tropicalis yeast, with minimum inhibitory concentration of 833,33 μg mL-1. The flow curves demonstrated a non Newtonian behavior with pseudoplastic characteristics, with excellent adjust to the Ostwald-de-Waele model. The temperature effect on the viscosity of pulps was verified through the equation of Arrhenius sort and analyzed in relation to activation energy, which highest value was obtained for the mulberry pulp. The sensory analysis of the prepared beverages pointed to the acceptability of the tasters, indicating potential to industrialization.
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Sanchez, Rodolfo Marcchiori [UNESP]. "Estudo fitoquímico e propriedades biológicas da Dipteryx alata Vogel (baru)". Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/123176.
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000824410.pdf: 976765 bytes, checksum: 5590643000ccb76d948b31c347eb1bba (MD5)Devido à importância do bioma cerrado, inclusive para a manutenção de outros biomas interligados, nas últimas décadas pesquisadores das mais variadas áreas vêm propondo alternativas de uso das espécies do cerrado como forma de preservar a fauna e flora local. Uma das formas para auxiliar na preservação dessas espécies esta o estudo sobre constituintes fitoquímicos e propriedades medicinais de plantas desse bioma usadas na medicina tradicional. O objetivo desse estudo é a confirmação do potencial terapêutico bem como da toxicidade dessas plantas usadas na medicina tradicional local, bem como estudar o potencial medicinal de plantas ainda não investigadas. A espécie Dipteryx alata Vogel (baru) é uma das espécies nativas do cerrado que apresenta grande potencial nutricional e farmacológico a ser investigado, pois segundo a medicina tradicional ela é utilizada no combate à bronquite, diarreia, disenteria, dor, dor de garganta, gripe, picada de cobra, tosse e como cicatrizante, entretanto, apenas a atividade contra picada de cobra foi cientificamente comprovada. Desta forma, na tentativa de aliar o valor nutricional da polpa dos frutos do baru a um possível efeito terapêutico, foram realizados estudos sobre os fitoconstituintes presentes nesta parte da planta, a fim de guiar estudos sobre as possíveis propriedades biológicas valorizando o fruto como um alimento nutracêutico, em áreas de ocorrência da planta que apresentam elevados índices de doenças negligenciadas. Os resultados dos estudos fitoquímicos mostraram a presença de alcaloides, taninos, flavonoides, glicosídeos cardiotônicos e saponinas em consideráveis concentrações e antraquinonas em baixa concentração. A presença desses fitoconstituintes forneceu suporte para a realização de ensaios para a determinação do potencial antiparasitário. A atividade antimicrobiana também foi avaliada devido ao uso medicinal da planta para infecções do trato ...
Due to the importance of the cerrado biome, including the maintenance of other interconnected biomes in recent decade’s researchers from different fields have proposed alternative use of the cerrado species as a way to preserve the local fauna and flora. One way to help the preservation of species is the study of the medicinal properties of plants of this biome used in traditional medicine. The objective of these studies is to confirm the therapeutic potential and the toxicity of these plants used in traditional local medicine as well as studying the medicinal potential of plants yet to be investigated. The specie Dipteryx alata Vogel (baru) is a native species of the cerrado with great nutritional and pharmacological potential to be investigated, because according to traditional medicine it is used to combat bronchitis, diarrhea, dysentery, pain, sore throat, flu, snakebite, cough and as cicatrizant, however, only the activity against snakebite has been scientifically proven. Therefore, trying to combine the nutritional value of baru fruits pulp to the potential therapeutic effect, studies on the determination of phytochemicals present were performed to guide studies on possible biological properties valuing the fruit as a nutraceutical food in areas of occurrence of the plant that show high negligible diseases indices. The results of the phytochemical studies showed the presence of alkaloids, tannins, flavonoids, saponins and cardiotonic glycosides in considerable amounts and anthraquinones at low concentration. The presence of these phytochemicals has given support for conducting tests to determine the antiparasitic potential. Antimicrobial activity was also evaluated due to the medicinal use of the plant for the urinary tract infections. In addition, the cytotoxicity of the pulp was also evaluated on LLC- MK 2 cells to support the safe use of the fruit. Antimicrobial assays were performed using the bacterial strains Proteus sp., E. ...
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徐永欣 i Wing-yan Pamela Tsui. "Phytochemical investigation of plants used in traditional medicine in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31213704.
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The Best M.Phil Thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,1995-1997published_or_final_version
Chemistry
Master
Master of Philosophy
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Romão, Gabriela Brasil. "Estudo in vitro da ação de extrato hidroetanólico de Cordia verbenacea DC. em espécies reativas de oxigênio de importância biológica /". Araraquara, 2016. http://hdl.handle.net/11449/141992.
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Orientador: André Gonzaga dos SantosCoorientador: Marcos Antônio Corrêa
Banca: Dulce Helena Siqueira Silva
Banca: Iguatemy Lourenço Brunetti
Resumo: A erva-baleeira, Cordia verbenacea DC., é uma espécie de planta originária do Brasil, encontrada principalmente na Floresta Tropical Atlântica. É largamente utilizada na medicina tradicional por apresentar, principalmente, ação anti-inflamatória. Dados recentes da literatura mostraram que esta ação está relacionada à presença de compostos fenólicos, flavonoides e sesquiterpenos, além de ser constatada a atividade antioxidante em diferentes extratos de C. verbenacea. Epécies reativas de oxigênio e nitrogênio são produzidas constantemente no organismo, podendo causar danos ou benefícios aos sistemas biológicos. Estão altamente relacionadas com o processo de envelhecimento do organismo, e, consequentemente, do envelhecimento cutâneo. A busca e pesquisa de cosméticos com ativos naturais com propriedades antioxidantes tem aumentado significativamente. Este estudo teve como objetivo avaliar a ação do extrato hidroetanólico 70 % de folhas de C. verbenacea (EtOH 70 %) em diferentes espécies reativas de oxigênio de importância biológica, para uma possível aplicação na prevenção do envelhecimento cutâneo. Inicialmente, foram comparados os extratos etanólico, hidroetanólico 70 % e aquoso de folhas de C. verbenacea a fim de selecionar o extrato com maior teor de compostos fenólicos totais e flavonoides totais, além de maior atividade antioxidante. O extrato EtOH 70 % foi selecionado para avaliação da atividade antioxidante in vitro frente a diferentes espécies reativas (radicais modelo ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Erva-baleeira, Cordia verbenacea DC., is a native Brazilian plant species, mainly found at the Atlantic Forest. It is widely used in traditional medicine mostly for its anti-inflammatory properties. Literature data shows that this activity is related to the presence of phenolic compounds, flavonoids and sesquiterpenes, it was also verified the antioxidant activity for different extracts of C. verbenacea. Reactive oxygen and nitrogen species are constantly produced in the organism and might cause damage or benefits on biological systems. They are highly related to the ageing process of the body and, consequently, to skin ageing. The research for natural cosmetics drugs with antioxidant properties has had a significant increase and, therefore, the aim of this study was to evaluate the antioxidant activity of an hydroethanolic extract of C. verbenacea leaves (EtOH 70 %) on different reactive oxygen species of biological importance. Initially, the ethanolic, hydroethanolic (70 %) and aqueous extracts of C. verbenacea leaves were compared to select the extract with a higher total phenolic content and total flavonoid content, as well as higher antioxidant activity. The EtOH 70 % extract was selected for in vitro evaluation of its antioxidant activity against different reactive species (radicals model or bioprocess model involving these species), but also to evaluate its cytotoxicity, the chromatographic profiles in TLC and HPLC and to develop a phytocosmetic contaning the extract, ... (Complete abstract click electronic access below)
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Lee, Iris. "Development of capillary electrophoresis for the analysis of phenolics and glucoraphanin in Brassica oleracea". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2012. https://ro.ecu.edu.au/theses/445.
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Capillary electrophoresis (CE) has been used increasingly more over the last decade in the area of food analysis. Numerous food products and food components have been analysed using this technique because of its high efficiency and short separation times. However, the inherent lack of detection sensitivity in CE combined with the complex matrices present in many food samples, especially those of plant origins, is one of the contributing factors to the limited development on CE in this particular area of food analysis. In this project, the potential of CE as a tool in the analysis of vegetables belonging to the family Brassica oleracea was investigated. Capillary zone electrophoresis (CZE), the most frequently used CE mode in food analysis, has been employed to quantitatively determine the phenolic acids present in vegetables of B. oleracea. A simple and rapid CZE method for the baseline resolution of four hydroxycinnamic acids was developed. Peak efficiencies and separation time were optimised by adjustment of the borate buffer concentration (15 mM sodium tetraborate pH 9.13) with the optimum method having a separation time of 7 min with detection limits ranging from 1.1 to 2.3 mg/kg of vegetables. The developed CZE method was applied to resolve the key flavonoids in broccoli extracts, however, detection sensitivity was poor for these compounds. To overcome this limitation an online pre-concentration method, large volume sample stacking (LVSS), was used to enable quantitative determination of flavonols in broccoli. This LVSS-CZE method allowed for the separation of two flavonols, kaempferol and quercetin, within 8 min with average enhancement factors of approximately 20 when compared to the original CZE method, giving detection limits of 0.6 and 0.9 mg/kg of broccoli. Resolution of the two flavonols was optimised by varying the borate buffer concentration and pH (the optimum values are 10 mM sodium tetraborate pH 8.40) and by using a longer capillary (85 cm). Different LVSS parameters including stacking voltage and sample injection times were also investigated. Micellar electrokinetic chromatography (MEKC), the second most commonly employed CE mode in food analysis, was used for the quantitative determination of glucoraphanin, a predominant glucosinolate in broccoli. A MEKC system was developed in which the surfactant, sodium cholate was used as the pseudo stationary phase and separation of glucoraphanin was achieved in less than 5 min with detection limits ranging from 0.1 to 4 mg/100g of vegetables or seeds. Furthermore, and as a direct result of the requirement for a glucoraphanin standard, a preparative HPLC experiment was devised for the undergraduate chemistry program within Edith Cowan University. All the developed CE methods were validated with repeatability studies and linearity measurements and then successfully applied to the quantitative determination of the target analytes in a range of B. Oleracea vegetables and seeds. The accuracy of the CE quantitative data was ascertained by comparison to those from HPLC analysis.
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Sweeney, Alan Peter. "Studies towards the development of two dimensional high performance liquid chromatographic systems for the separation of complex samples /". View thesis, 2002. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20031013.085943/index.html.
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Thesis (Ph.D.) -- University of Western Sydney, 2002.A thesis submitted to fulfil the requirements for the degree of Doctor of Philosophy, School of Science, Food and Horticulture, University of Western Sydney, August, 2002. Includes bibliographical references (leaves 247-260).
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Silva, Mayara Gobetti Fernandes da. "Avaliação do potencial alelopático de raízes de capim annoni-2 (Eragrostis plana Nees) e estudo fitoquímico". Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1113.
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CAPESO Capim Annoni-2 (Eragrostis plana Nees), considerado uma planta daninha invasora e de difícil erradicação, tem a capacidade de dominar o meio em que se encontra, sobrepondo-se a espécies nativas e agroeconômicas. Parte desta capacidade está relacionada a efeitos alelopáticos causados por aleloquímicos liberados por esta espécie. Assim, a identificação desses aleloquímicos pode ser uma boa alternativa para produção de bio-herbicidas. Neste estudo, determinou-se o potencial alelopático de extratos brutos de éter de petróleo, acetato de etila e metanol provenientes da raíz de E. plana Nees coletadas no verão na área experimental do curso de Agronomia da UTFPR - câmpus Pato Branco, como também um estudo fitoquímico para elucidação estrutural de possíveis aleloquímicos. O potencial alelopático foi avaliado a partir de bioensaios de germinação e crescimento de radícula e hipocótilo, utilizando-se duas espécies receptoras (Ipomoea grandifolia e Euphorbia hetetophylla) e três concentrações dos extratos brutos (200, 400 e 600 ppm). Como resultados observou-se que os extratos brutos de éter de petróleo e acetato de etila atuam principalmente na cinética do processo de germinação, retardando-o, enquanto que o extrato bruto de metanol atuou, sobretudo na diminuição da germinação, inibindo 75,4% em comparação com o branco (água destilada), causando até deformidades e mortes de plântulas, estes dados para a espécie receptora E. heterophylla, a mais afetada. Quanto ao bioensaio de crescimento de hipocótilo e radícula, o extrato bruto de metanol foi o menos eficaz, destacando-se o extrato bruto de éter de petróleo a 600 ppm contra a espécie receptora I. grandifolia, causando uma diminuição no crescimento da radícula e hipocótilo de 66,3% e 65,5%, respectivamente, e o extrato bruto de acetato de etila também a 600 ppm contra a espécie receptora E. heterophylla, causou uma diminuição de 63,6% e 72% do comprimento do hipocótilo e radícula, respectivamente, ambos em comparação com seus respectivos brancos (água destilada). Através do estudo fitoquímico foi proposta a estrutura de um diterpeno, por meio do fracionamento e purificação do extrato bruto de éter de petróleo, e um composto, cuja estrutura não foi ainda completamente elucidada, este a partir do extrato bruto de metanol. Os efeitos alelopáticos apresentados pelas raízes do Capim Annoni-2, foram bastante efetivos, podendo estes serem atribuídos as substâncias fitotóxicas isoladas nesse estudo.
The Grass Annoni-2 (Eragrostis plana Nees), considered a noxious invasive and difficult to eradicate plant has the capacity to dominate the environment they are in, superseding Agrieconomic and native species. Part of this ability is related to allelopathic effects caused by allelochemicals released by this species. Thus, the identification of these allelochemicals can be a good alternative for the production of bio-herbicides. In this study, we determined the allelopathic potential of crude extracts of petroleum ether, ethyl acetate and methanol from the root of E. plana Nees collected in the summer in the experimental area of the course of Agronomy UTFPR - Pato Branco campus, as well as a phytochemical study for structural elucidation of potential allelochemicals. The allelopathic potential was assessed from bioassays of germination and growth of radicle and hypocotyl, using two receptor species (Ipomoea grandifolia and Euphorbia hetetophylla) and three concentrations of crude extracts (200, 400 and 600 ppm). As a result it was found that crude extracts of petroleum ether and ethyl acetate act mainly on the kinetics of the germination process by slowing it, while the crude methanol extract worked, especially in reducing the germination inhibiting 75.4% in comparison with blank (distilled water), causing deformities, and even death of seedlings these data to the recipient E. heterophylla, most affected. Regarding the growth bioassay hypocotyl and radicle, crude methanol extract was the least effective, highlighting the crude extract of petroleum ether at 600 ppm against receiving I. grandifolia species, causing a decrease in the growth of radicle and hypocotyl 66.3% and 65.5%, respectively, and the crude ethyl acetate extract also receiving 600 ppm against E. heterophylla caused a decrease of 63.6% and 72% of the length of the hypocotyl and radicle respectively, both compared with their white (distilled water). Through phytochemical study was proposed structure of a diterpene, through the fractionation and purification of the crude extract of petroleum ether, and a compound whose structure has not been fully elucidated, this from crude methanol extract. The allelopathic effects shown by the roots of the grass Annoni-2, were quite effective, these can be attributed to the isolated phytotoxic substances in this study.
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Mokgadi, Janes. "Pressurized hot water extraction of nutraceuticals and organic pollutants from medicinal plants". Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1004999.
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This thesis explores the robustness and the versatility of pressurized hot water extraction (PHWE) for a variety of analytes and matrices. Applications discussed include: selective extraction of alkaloids in goldenseal followed by their degradation studies; in-cell clean-up of pesticides in medicinal plants employing custom made molecularly imprinted polymers (MIPs) sorbents; in-cell pre-concentration followed by desorption of aflatoxins in plants with MIPs; desorption of pesticides from electrospun nanofiber sorbents; and removal of templates from MIPs sorbents. It was demonstrated that selective extractions could be achieved by just changing the temperature of water while adjusting the pressure. For instance, the alkaloids in goldenseal (hydrastine and berberine), were extracted at 140 °C, 50 bars, 1 mL min⁻¹ in 15 min; organochlorine pesticides from medicinal plants were extracted at 260 °C, 80 bars, 1 mL min-1 in 10 min; while aflatoxins AFG2, AFG1, AFB2 and AFB1 were extracted at 180 °C, 60 bars and a flow rate of 0.5 mL min⁻¹ in 10 min. The selectivity of PHWE was further enhanced by combining it with selective MIPs sorbents at higher temperatutes. In-cell clean-up of interfering chlorophyll was successfully removed from the medicinal plants during pesticides analysis while clean-up of aflatoxins AFG2, AFG1, AFB2 and AFB1 was achieved in two extraction cells connected in series. Ultrasound was also combined with PHWE for extraction of hydrastine and berberine at 80 °C and 40 bars in 30 min. PHWE was further evaluated for removal of templates from quercetin, phthalocynine and chlorophyll MIPs. The templates were thoroughly washed off their MIPs within 70 min with PHWE compared to over 8 h for Soxhlet and ultrasound assisted extraction. Pesticides were also desorbed from electrospun nanofibers at 260 °C, 80 bars in 10 min employing only water at 0.5 mL min⁻¹. In the light of green chemistry, the decrease in the usage of organic solvents was 100%, resulting in no organic solvent waste.
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Moro, Isabela Jacob. "Avaliação da atividade citotóxica e tipo de morte em linhagens celulares humanas tratadas com derivados vegetais e metabólitos secundários de Baccharis trimera (Less.) DC. /". Araraquara, 2016. http://hdl.handle.net/11449/141942.
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Orientador: André Gonzaga dos SantosCoorientador: Christiane Pienna Soares
Banca: Dulce Helena Siqueira Silva
Banca: Denise Crispim Tavares
Resumo: Produtos derivados de fontes vegetais tem demonstrado seu potencial no combate a diversas doenças, inclusive o câncer, à exemplo dos alcaloides derivados de Catharantus roseus (L.)G. Don, vincristina e vimblastina. A diversidade estrutural das moléculas encontradas em espécies vegetais concebem perspectivas de uso in natura bem como servem de inspiração para o desenvolvimento de outras entidades químicas que serão destinadas ao combate de doenças. O material de estudo pertence a espécie Baccharis trimera (Less.) DC, popularmente conhecida como carqueja e com amplo uso tradicional, principalmente para o alívio de afecções digestivas. O estudo teve por objetivo o fracionamento cromatográfico de derivados vegetais de partes aéreas de B. trimera e a avaliação da citotoxicidade e estudo de morte em linhagens de células humanas normal e tumorais tratadas com o OE, suas frações e componentes, além da flavona eupatorina isolada do extrato acetato de etila. O potencial citotóxico foi avaliado através do método da sulforrodamina B e os estudos de morte através de ensaios de Anexina-V, Hoechst/iodeto de propídeo e ativação de caspase-3. As linhagens celulares humanas utilizadas foram de câncer de mama (MCF-7), hepatocarcinoma (HepG2) e a linhagem de mama normal (MCF-10). As amostras avaliadas foram o óleo essencial, suas frações e componentes (α-humuleno, trans-cariofileno e óxido de cariofileno), além da eupatorina. Os constituintes majoritários do óleo essencial identificados por CG-E... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Natural products diversity is an important source to find potential treatments against various diseases, including cancer. Vincristine and vimblastine, alkaloids derived from Catharantus roseus (L.) L. Don, are some of the examples. The structural diversity of molecules from plant species allow the in natura usage and also the development of other chemical entities that will be used to diseases control. Baccharis trimera (Less.) DC., popularly known as carqueja, has an extensive traditional use, especially for digestive disorders. The aims of this study were the chromatographic fractionation of aerial parts from carqueja, in vitro evaluation of the cytotoxic potential through sulforhodamine B assay and cellular death by Annexin-V assay, Hoechst/propidium iodide method and caspase-3 activation, in normal and tumor cell lines treated with essential oil, its fractions and components, and the flavone eupatorin isolated from ethyl acetate extract. The cell lines used were human breast cancer (MCF-7), hepatocellular carcinoma (HepG2) and normal breast line (MCF-10a). The evaluated samples were: essential oil, its fractions and components (α-humulene, β- caryophyllene and caryophyllene oxide) and eupatorin. The major constituents of the essential oil identified by GC-MS were: β-caryophyllene (18.9%), bicyclogermacrene (15.6%), germacrene D (10.5%), δ-cadinene (6.6%). Other components of the essential oil, such as α-humulene (2.3%) and caryophyllene oxide (2.9%) were also identified.... (Complete abstract click electronic access below)
Mestre
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Silva, Paulo Roberto Arbex [UNESP]. "Caracterização da composição química dos óleos essenciais de Lychnophora pinaster Mart. em função da sazonalidade". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/93527.
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silva_pss_me_botfca.pdf: 1572244 bytes, checksum: cb40193cc7c83afdae5bc11bdedce824 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Avaliou-se a influência da sazonalidade no rendimento e composição química dos óleos essenciais de Lychnophora pinaster. O material vegetal foi coletado em Carrancas e Ingaí, Minas Gerais, no verão, outono, inverno e primavera de 2012. Foram utilizadas três populações nativas, denominadas Serra Branca, Serra do Salto (provenientes de Carrancas) e Serra da Arnica (Ingaí). Foram amostrados 25 acessos por população e os óleos essenciais das folhas extraídos por hidrodestilação e a análise da composição química conduzida em CG-EM. A sazonalidade não exerceu influência no rendimento médio de óleo essencial das populações Serra Branca e Serra do Salto e destas, Serra do Salto apresentou em todas as estações do ano maior rendimento médio (0,43% a 0,61%). Para Serra da Arnica observou-se estatisticamente influência da sazonalidade no rendimento médio de óleo essencial no inverno (0,79%). Os óleos essenciais das três populações apresentaram as mesmas substâncias, cujas majoritárias foram o trans-cinamato de metila e o trans-cariofileno. Serra Branca apresentou em todas as estações a maior proporção relativa média de trans-cariofileno (16,01% a 23,1%), alfa-humuleno (4,64% a 6,7%), óxido de cariofileno (4,79% a 5,76%) e cedr-8-(15)-en-9-alfa-ol (1,98% a 2,73%). Nesta população, os acessos que mais se correlacionaram com o acúmulo das substâncias com maior proporção relativa média, nas quatro estações foram: Pop 101, Pop 103 e Pop 125 (óxido de cariofileno), Pop 113 e Pop 123 (trans-cariofileno e alfa-humuleno) e Pop 112 e Pop 119 (trans-cinamato de metila). Serra do Salto apresentou a...
The influences of seasonality on the yield and the chemical composition of the essential oils from Lychnophora pinaster were evaluated. The plant material was collected in the regions of Carrancas and Ingaí, State of Minas Gerais, Brazil, during the whole year of 2012. Three native populations were sampled: Serra Branca, Serra do Salto (Carrancas), and Serra da Arnica (Ingaí) – a total sample of 75 plants (25 for each population). The essential oils were extracted by hydro-distillation and the analyses of chemical composition were made by GC-MS. The seasonality did not present a significant effect on the average essential oil yield of the Carrancas populations – Serra do Salto showed the highest values on essential oil production (0.43% to 0.61%). For the population of Serra da Arnica, the seasonality presented significant influence on essential oil yield and the winter sample showed the highest values in this population (0.79%). Chemically all populations presented the same composition and the main substances were trans-methyl cinnamate and trans- caryophyllene. The Serra Branca population presented the highest relative proportion of trans-caryophyllene (16.01% to 23.1%), alpha-humulene (4.64% to 6.7%), caryophyllene oxide (4.79% to 5.76%) and cedr-8-(15)-en-9-alpha-ol (1.98% to 2.73%). In this population the plants with highest correlation with the accumulation of main substances during the whole year were Pop-101, Pop-103... (Complete abstract click electronic access below)
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Silva, Paulo Sérgio Siberti da 1988. "Caracterização da composição química dos óleos essenciais de Lychnophora pinaster Mart. em função da sazonalidade /". Botucatu, 2013. http://hdl.handle.net/11449/93527.
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Orientador: Marcia Ortiz Mayo MarquesBanca: Elizabeth Orika Ono
Banca: Paulo Roberto Hrihorowitsch Moreno
Resumo: Avaliou-se a influência da sazonalidade no rendimento e composição química dos óleos essenciais de Lychnophora pinaster. O material vegetal foi coletado em Carrancas e Ingaí, Minas Gerais, no verão, outono, inverno e primavera de 2012. Foram utilizadas três populações nativas, denominadas Serra Branca, Serra do Salto (provenientes de Carrancas) e Serra da Arnica (Ingaí). Foram amostrados 25 acessos por população e os óleos essenciais das folhas extraídos por hidrodestilação e a análise da composição química conduzida em CG-EM. A sazonalidade não exerceu influência no rendimento médio de óleo essencial das populações Serra Branca e Serra do Salto e destas, Serra do Salto apresentou em todas as estações do ano maior rendimento médio (0,43% a 0,61%). Para Serra da Arnica observou-se estatisticamente influência da sazonalidade no rendimento médio de óleo essencial no inverno (0,79%). Os óleos essenciais das três populações apresentaram as mesmas substâncias, cujas majoritárias foram o trans-cinamato de metila e o trans-cariofileno. Serra Branca apresentou em todas as estações a maior proporção relativa média de trans-cariofileno (16,01% a 23,1%), alfa-humuleno (4,64% a 6,7%), óxido de cariofileno (4,79% a 5,76%) e cedr-8-(15)-en-9-alfa-ol (1,98% a 2,73%). Nesta população, os acessos que mais se correlacionaram com o acúmulo das substâncias com maior proporção relativa média, nas quatro estações foram: Pop 101, Pop 103 e Pop 125 (óxido de cariofileno), Pop 113 e Pop 123 (trans-cariofileno e alfa-humuleno) e Pop 112 e Pop 119 (trans-cinamato de metila). Serra do Salto apresentou a... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The influences of seasonality on the yield and the chemical composition of the essential oils from Lychnophora pinaster were evaluated. The plant material was collected in the regions of Carrancas and Ingaí, State of Minas Gerais, Brazil, during the whole year of 2012. Three native populations were sampled: Serra Branca, Serra do Salto (Carrancas), and Serra da Arnica (Ingaí) - a total sample of 75 plants (25 for each population). The essential oils were extracted by hydro-distillation and the analyses of chemical composition were made by GC-MS. The seasonality did not present a significant effect on the average essential oil yield of the Carrancas populations - Serra do Salto showed the highest values on essential oil production (0.43% to 0.61%). For the population of Serra da Arnica, the seasonality presented significant influence on essential oil yield and the winter sample showed the highest values in this population (0.79%). Chemically all populations presented the same composition and the main substances were trans-methyl cinnamate and trans- caryophyllene. The Serra Branca population presented the highest relative proportion of trans-caryophyllene (16.01% to 23.1%), alpha-humulene (4.64% to 6.7%), caryophyllene oxide (4.79% to 5.76%) and cedr-8-(15)-en-9-alpha-ol (1.98% to 2.73%). In this population the plants with highest correlation with the accumulation of main substances during the whole year were Pop-101, Pop-103... (Complete abstract click electronic access below)
Mestre
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Dalbosco, Talita. "Avaliação do potencial alelopático dos extratos foliares brutos do capim-annoni-2 (Eragrostis plana Nees) e estudo do óleo essencial". Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/737.
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O capim annoni-2, Eragrostis plana Nees, é uma espécie vegetal africana conhecida por sua capacidade invasora e, por este motivo, classificada como planta daninha, sendo considerada a mais agressiva e de mais difícil controle nos campos sulinos. Esta espécie ativa mecanismos de inibição de crescimento e germinação de outras espécies vizinhas no fenômeno denominado alelopatia. O estudo fitoquímico de E. plana Nees, justifica-se por se tratar de uma espécie com suposta atividade alelopática, bem como, em função de suas características e do impacto biológico e econômico causado por ela. Com o objetivo de identificar e caracterizar moléculas bioativas e avaliar seus efeitos alelopáticos, foram realizados os experimentos. As folhas de E. plana Nees, foram coletadas no inverno e verão, para análise fitoquímica, e a obtenção do óleo essencial das amostras foi feita por hidrodestilação e, posteriormente, filtrados e refrigerados até a análise cromatográfica gasosa acoplada a espectrometria de massas. Para os metabólitos secundários não voláteis, o material botânico foi submetido a extração exaustiva a frio, com éter de petróleo e acetato de etila. Os extratos foram submetidos à técnica de Infravermelho. Na identificação alelopática foram utilizadas sementes da espécie Ipomoea grandifolia em dois bioensaios comumente realizados em estudos alelopáticos. Os testes, de germinação e alongamento de radícula e hipocótilo foram monitorados diariamente por 7 dias, em condições controladas e realizados em câmaras BOD (Demanda Bioquímica de Oxigênio). Para os dois testes foram empregados 5 doses com diferentes concentrações de cada extrato em volume de 5 mL em cada placa de Petri. O delineamento utilizado foi o inteiramente casualizado com 4 repetições, sendo água destilada e Tween 80 + solvente extratores como testemunhas. Os dados foram submetidos ao teste de homogeneidade de variâncias, pelo teste de Cochran C e à análise de normalidade pelo teste de Shapiro–Wilk, com posterior análise de variância, ANOVA e teste de Tukey a 5% de significância para as variáveis homogêneas. O efeito alelopático apresentado pelas folhas de E. plana Nees, pode estar relacionado com os teores de terpenos observados na análise do óleo essencial, uma vez que os mesmos, possuem propriedades alelopáticas, conforme relatos da literatura. Os extratos brutos expressaram o potencial alelopático da E. plana Nees, interferindo no desenvolvimento da espécie receptora. A utilização destes extratos de forma direta ou como fonte de moléculas químicas, pode colaborar no desenvolvimento de novos bio-herbicidas.The grass - 2 lovegrass , Eragrostis plana Nees , is an African plant species known for its invasive capacity and , therefore , classified as a weed , and is considered the most aggressive and more difficult to control in the southern fields . This species active mechanisms of inhibition of germination and growth of neighboring species in the phenomenon called allelopathy . The phytochemical study of E. plana Nees , is justified because it is a species with alleged allelopathic activity and, depending on its characteristics and the biological and economic impact caused by it . In order to identify and characterize bioactive molecules and evaluate their allelopathic effects , the experiments were performed . The leaves of E. plana Nees were collected in winter and summer , for phytochemical analysis , and obtain the essential oil sample was taken by hydrodistillation and subsequently filtered and chilled to the gas chromatographic analysis coupled with mass spectrometry . For non- volatile secondary metabolites , the plant material was subjected to exhaustive cold extraction with petroleum ether and ethyl acetate . The extracts were subjected to IR technique . In allelopathic identification seeds of Ipomoea grandifolia species commonly performed in two bioassays in allelopathic studies were used . The tests , germination and radicle and hypocotyl elongation were monitored daily for 7 days under controlled and conducted in chambers BOD ( Biochemical Oxygen Demand ) conditions . For both tests 5 doses with different concentrations of each extract volume of 5 mL in each Petri dish were used. The experimental design was completely randomized with 4 replications, with distilled water and Tween 80 + solvent extractors as witnesses . The data were submitted to variance homogeneity test, the Cochran C and analysis of normality by the Shapiro - Wilk test, with subsequent analysis of variance , ANOVA and Tukey test at 5 % significance level for the homogeneous variables. The allelopathic effect exhibited by the leaves of E. Nees plane can be related to the levels observed in the analysis of terpenes of essential oil , since they possess allelopathic effects , as reported in the literature. The extracts expressed the allelopathic potential of E. plana Nees , interfering with the development of the receiving species . The use of these extracts directly or as a source of chemical molecules , can collaborate in developing new bio - herbicides.
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Adams, Zanele. "Comparative phytochemical analyses of Aloe Ferox Mill. found in Eastern and Western Cape provinces in South Africa". Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1013114.
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Castro, Rogério Cardoso de. "Caracterização por espectrometria de massas e investigação das atividades anti-inflamatória e gastroprotetora do extrato etanólico e diterpenos clerodânicos de folhas de Casearia sylvestris Swartz /". Araraquara, 2016. http://hdl.handle.net/11449/139430.
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Orientador: André Gonzaga dos SantosBanca: Fábio Ferreita Perazzo
Banca: Gustavo Henrique Bianco de Souza
Banca: Taís Maria Bauab
Banca: Alexandra Ivo de Medeiros
Resumo: O objetivo geral deste trabalho foi realizar um estudo químico-farmacológico do extrato etanólico de folhas de Casearia sylvestris Swartz (EEtCs), frações obtidas por extração em fase sólida (EFS1: apolar; EFS2: rica em diterpenos clerodânicos; EFS3: polar) e padrões de diterpenos clerodânicos (DC). Os objetivos da parte química foram caracterizar os padrões de DC por espectrometria de massas (full scan e fragmentação) com fonte de ionização por spray de elétrons (ESI-MS e MSn) e identificar DC no EEtCs e na EFS2 por ESI-MS, ESI-MSn e por cromatografia em camada delgada de alta eficiência com detecção por imagem química formada por espectrometria de massas com fonte de dessorção por spray de elétrons (HPTLC-DESI-MS-IMAGING). A parte farmacológica consistiu na investigação da atividade anti-inflamatória e gastroprotetora do EEtCs, frações (EFS1-3) e padrões de DC. A atividade anti-inflamatória foi avaliada por meio de ensaios em ratos, pleurisia induzida pela carragenina e edema de pata induzido por uma fosfolipase A2 de veneno de Bothrops jararacussu (BthTX-II), e os seguintes ensaios in vitro: atividade enzimática das ciclo-oxigenases 1 e 2 (COX-1 e COX-2) e produção de óxido nítrico (NO) e prostaglandina E2 (PGE2) por macrófagos estimulados por lipopolissacarídeo. A atividade gastroprotetora foi avaliada em modelo de lesões gástricas induzidas por indometacina em ratos e ensaio in vitro de atividade anti-Helicobacter pylori. Os resultados levaram às conclusões a seguir. A caracterização dos padrões de DC por espectrometria de massas permitiu estabelecer o padrão de fragmentação dos DC com anel diacetálico do tipo das casearinas, o qual representa uma importante fonte de informação para desreplicação em estudos metabolômicos de extratos vegetais... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aim of this study was to carry out a chemical-pharmacological study of the ethanol extract from leaves of Casearia sylvestris Swartz (EtECs), fractions obtained by solid phase extraction (SPE1: nonpolar; SPE2: rich in clerodane diterpenes; SPE 3: polar) and standards of clerodane diterpenes (CD). The objectives of the chemical step was to characterize standards of CD by mass spectrometry (full scan and fragmentation) using electrospray ionization (ESI-MS and MSn) and to identify CD in EtECs and SPE2 by ESI-MS, ESI-MSn and high performance thin layer chromatography/desorption electrospray ionization mass spectrometry imaging (HPTLC-DESI-MS-IMAGING). The pharmacological study consisted in investigation of anti-inflammatory and gastroprotective activities of EtECs, fractions (SPE1-3) and CD standards. The anti-inflammatory activity was assessed in rats through pleurisy induced by carrageenan and paw edema induced by phospholipase A2 from Bothrops jararacussu venom (BthTX-II), and the following in vitro assays: enzymatic activity of cyclooxygenases 1 and 2 (COX-1 and COX-2) and macrophage stimulation by lipopolysaccharide to investigate the production of nitric oxide (NO) and prostaglandin E2 (PGE2). The gastroprotective activity was assessed in a model of indomethacin-induced gastric lesions in rats and in vitro assay of anti-Helicobacter pylori activity. The results led to the following conclusions. The characterization of the standards of CD by mass spectrometry demonstrated that it was possible to establish the fragmentation pattern of CD with diacetalic ring like casearins, which is an important source of information for dereplication in metabolomics studies of plant extracts... (Complete abstract click electronic access below)
Doutor
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任黛. "篦子三尖杉的化學成分研究". Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3952202.
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Fuku, Sandile Lawrence. "An investigation of the phytochemistry and biological activity of Asparagus laricinus". Thesis, Bloemfontein: Central University of Technology, Free State, 2014. http://hdl.handle.net/11462/246.
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Thesis (D. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, 2014Medicinal plants are part of indigenous people‟s cultural heritage, thus since ancient times treatment of various diseases using medicinal plants has been part of human culture. The value of medicinal plants to mankind has been very well proven. It is estimated that 70% to 80% of people worldwide rely mainly on traditional health care systems, especially on herbal medicines (Stanley and Luz, 2003). In many societies the medicinal properties of plants were discovered mostly through trial and error, but use was also influenced by the belief systems of the people involved and often became entangled with religious and mythical practices (Mathias et al., 1996). Besides that, medicinal plants are proving to be rich resources of constituents that can be used in drug development and synthesis. Medicinal plants have been a source of a wide variety of biologically active compounds for many centuries and have been used extensively as crude material or as pure compounds for treating various disease conditions. Between 1% and 10% of plants out of an estimated 250 000 to 500 000 species of plants on earth are used by humans (Boris, 1996). 2 Plants used for medicinal purposes contribute significantly to the development of major medical drugs that are used today. Most common medicines have compounds extracted from plants as their primary active ingredients and many have provided blueprints for synthetic or partially synthesized drugs (Simpson and Ogorzaly, 2001). There has been a major resurgence of interest in traditionally used medicinal plants, with a number of international and local initiatives actively exploring the botanical resources of southern Africa with the intention to screen indigenous plants for pharmacologically active compounds (Gurib-Fakim et al., 2010; Rybicki et al., 2012). South Africa is considered a “hot spot” for biodiversity and more than 22 000 plant species occur within its boundaries. This represents 10% of the world‟s species, although the land surface of South Africa is less than 1% of the earth‟s surface (Coetzee et al., 1999). Plants have also been used by man for various purposes, among others as arrow and dart poisons for hunting, poisons for murder, hallucinogens used for ritualistic purposes, stimulants for endurance and hunger suppression, as well as medicine (Duke et al., 2008; Cragg and Newman, 2005). A derivative of the polyhydroxy diterpenoid ingenol isolated from the sap of Euphorbia peplus (known as “petty spurge” in England or “radium weed” in Australia), which is a potential chemotherapeutic agent for skin cancer, is currently under clinical development by Peplin Biotech for the topical treatment of certain skin cancers (Kedei et al., 2004; Ogbourne et al., 2004). Combretastatin A-4 phosphate, 3 a stilbene derivative from the South African bush willow, Combretum caffrum, acts as an anti-angiogenic agent causing vascular shutdowns in tumors (Newman et al., 2005; Holwell et al., 2002). Further reliance on plants for drug development is demonstrated by the use of galantamine hydrobromide, an alkaloid obtained from the plant Galanthus nivalis used traditionally in Turkey and Bulgaria for the treatment of Alzheimer‟s disease (Howes et al., 2003; Heinrich and Teoh, 2004). The plant chemicals used for the above-mentioned purposes are secondary metabolites, which are derived biosynthetically from plant primary metabolites (e.g. carbohydrates, amino acids and lipids). Secondary metabolites are organic compounds that are exclusively produced by plants and that are not directly involved in the normal growth, development and reproduction of a plant (Firn and Jones, 2003). Yet, they have many functions that are important for the plant‟s long-term health and appearance. Plants, being stationary, have to cope with a number of challenges, including engineering their own pollination and seed dispersal, local variation in the supply of the simple nutrients that they require to synthesize their food and the coexistence of herbivores and pathogens in their immediate environment. Plants have therefore evolved secondary biochemical pathways that allow them to synthesize a spectrum of organic molecules, often in response to specific environmental stimuli, such as herbivore-induced damage, pathogen attacks, or nutrient deprivation (Reymond et al., 2000; Hermsmeier et al., 2001). 4 The biosynthesis of secondary metabolites is derived from the fundamental processes of photosynthesis, glycolysis and the Krebs cycle to afford biosynthetic intermediates which, ultimately, result in the formation of secondary metabolites also known as natural products (Dewick, 2002). It is hypothesized that secondary metabolism utilizes amino acids and the acetate and shikimate pathways to produce “shunt metabolites” (intermediates) that have adopted an alternate biosynthetic route, leading to the biosynthesis of secondary metabolites (Sarker et al., 2006). Modifications in the biosynthetic pathways that produce secondary metabolites are probably due to natural causes (e.g. viruses or environmental changes) or unnatural causes (e.g. chemical or radiation processes) in an effort to adapt or provide longevity for the plant (Sarker et al., 2006). Plants‟ secondary metabolites can be classified into several groups according to their chemical classes, such alkaloids, terpenoids and phenolics (Harbone, 1984; Wink, 2003).
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Godschalx, Adrienne Louise. "Symbiosis with Nitrogen-fixing Rhizobia Influences Plant Defense Strategy and Plant-predator Interactions". PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3644.
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As sessile organisms, plants evolved a plethora of defenses against their attackers. Given the role of plants as a primary food source for many organisms, plant defense has important implications for community ecology. Surprisingly, despite the potential to alter entire food webs and communities, the factors determining plant investment in defense are not well-understood, and are even less understood considering the numerous symbiotic interactions in the same plant. Legume-rhizobia symbioses engineer ecosystems by fixing nitrogen from the atmosphere in trade for plant photosynthates, yet connecting symbiotic resource exchange to food web interactions has yet to be established. Here I test how rhizobia influence plant defense and tritrophic interactions in lima bean (Fabaceae - Phaseolus lunatus L.): a model plant in chemical ecology research characterized by a broad range of different defenses. Examining suites of traits among lima bean genotypes, highly cyanogenic cultivars and wild type plants (high cyanotypes) produce more hook-shaped trichomes, as a putative combined approach of chemical and mechanical defenses, forming defense syndromes to protect against multiple feeding guilds (Chapter 2). Testing costs that may have contributed to forming tradeoffs among strategies, high cyanotypes show reduced fitness under plant-plant competition relative to low cyanotypes, but when challenged with herbivory, high cyanotypes fitness reductions are no longer evident (Chapter 3). Young leaves, not reproductive organs, are the most cyanogenic lima bean organ, and removal quantitatively decreases fitness, supporting assumptions that the most valuable tissues will be most highly defended (Chapter 4). Testing the degree to which nitrogen-fixing rhizobia contribute to cyanogenesis, high cyanotypes form more nodules than low cyanotypes. Quantitative relationships between nodule number and plant traits highlight the role symbiotic investment plays a role in plant defense and nutritive phenotype, while simultaneously, genotypically-determined levels of defense shape plant investment in symbiosis (Chapter 5). Interestingly, traits that trade off by cyanotype (i.e. high cyanogenesis but low indirect defense) reflect the patterns in plants with nitrogen-fixing rhizobia. Rhizobia-inoculated lima beans show reduced indirect defenses, recruiting fewer parasitoid wasps (Chapter 6) and predatory ants (Chapter 7). Examining plant-ant attraction in greater detail, ants prefer headspace regions above EFN droplets, corresponding with species-specific differences in suites of volatiles, indicating EFN, like floral nectar, can be scented to manipulate insect behavior (Chapter 8). Overall, understanding when investing in traits to recruit predators is more effective than investing in defensive chemistry, and how particular ecological contexts, such as symbioses can influence the outcome of defense allocation strategies remains a fascinating area of research. Determining the mechanisms underlying why rhizobia and other belowground microbial symbionts influence their host plants' above ground interactions, whether plants traits affected by symbiotic microbes are simply a function of the costs and benefits from resource exchange, or whether symbionts can influence the success of primarily direct versus indirectly defended plants is an important question for understanding complex trophic systems and connecting to agricultural implications for more effective biological pest control.
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Ali, Marina. "Antimicrobial metabolites from Australian Acacia : thesis /". View thesis, 1998. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030825.144902/index.html.
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Nascimento, Marcel da Silva. "Abordagem fitoquímica e avaliação da atividade antioxidante e antiinflamatória do extrato e frações da entrecasca da Mimosa hostilis Benth". Pós-Graduação em Ciências Fisiológicas, 2013. https://ri.ufs.br/handle/riufs/3966.
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The use of medicinal plants for healing and prevention diseases is one of the oldest practices of mankind. Among the many plants used in folk medicine, the Mimosa hostilis Benth known as jurema black popularly used in skin problems and inflammation in general. This study aimed to perform phytochemical screening and evaluate the antioxidant and antiinflammatory activity of hydroethanolic extract (HEE) and its fractions, hexane (HXF), chloroform (CLF), ethyl acetate (EAF) and hydromethanol (HMF) obtained from the inner bark of M.hostilis. For this, the HEE and their fractions were subjected to classic phytochemical trials which involved qualitative chemical reactions that resulted in the confirmation of metabolites belonging to the classes of flavonoids, tannins, xanthones, triterpenoids, free steroids, saponins and phenols. The total phenolic content was also performed using the Folin-Ciocalteu method which it was higher in EAF (527.71 ¡Ó 30.80 mg GAE.g-1). To evaluate the antioxidant activity were used kidnapping free radical DPPH (2,2-diphenyl-1-picryl-hydrazyl) and inhibition of lipid peroxidation quantified by the thiobarbituric acid reactive substances (TBARS). The HEE, EAF and HMF had a higher inhibition percentage of DPPH free radical with indices 95.84%, 94.66% and 95.40%, respectively. The HEE and EAF showed higher lipid peroxidation inhibition percentage when induced by AAPH, while HMF was higher when induce by FeSO4. The biological activity investigated was antiinflammatory by reducing of ear edema and myeloperoxidase (MPO) activity. Ear edema was induced by 12-O-tetradecanoylphorbol acetate (TPA, 1 Ýg/ear) and the HEE effect or their fractions was evaluated by co-administration there of in doses of 1.0 and 3.0 mg/ear, with TPA in the right ear. Left ear was administered only the vehicle (acetone). After 6 h, the ear sites were removed and the edema was expressed from the mass variation between left and right ear, as well the myeloperoxidase activity (MPO) was measured. Co-administration of HEE caused significant inhibition (p<0.001) swelling and MPO activity (p<0.05) at both doses. In turn, HXF, CLF, EAF and FHM reduced similarly edema at a dose of 3.0 mg/ear and percent inhibition de 78%, 71%, 75% and 65%, respectively. The FAE and FHM inhibited MPO activity at doses 1.0 and 3.0 mg/ear (FAE: 86% and 93% for 1.0 and 3.0 mg/ear [p<0.001], respectively; FHM: 40% and 52% for 1.0 and 3.0 mg/ear [p<0.05], respectively). The CLF caused inhibition at a dose of only 3.0 mg/ear (72%, p<0.05) and HXF did not significantly alter MPO activity induced by TPA. If taken together these results indicate that the HEE and its fractions have antioxidant and antiinflammatory, allowing future studies with this plant to obtain bioactive compounds.O uso de plantas medicinais para cura e prevencao de doencas e uma das praticas mais antigas da humanidade. Uma das plantas utilizadas na medicina popular e a Mimosa hostilis Benth conhecida como jurema preta e usada popularmente em problemas de pele e inflamacoes em geral. O presente trabalho teve por objetivo realizar a triagem fitoquimica e avaliar a atividade antioxidante e anti-inflamatoria do extrato hidroetanolico (EHE) e das suas fracoes hexanica (FHX), cloroformica (FCL), acetato de etila (FAE) e hidrometanolica (FHM) obtidas das entrecascas da M. hostilis. Para isso, o EHE e suas fracoes foram submetidos a prospeccao fitoquimica classica a qual envolveu reacoes quimicas qualitativas que resultaram na confirmacao de metabolitos pertencentes as classes dos flavonoides, taninos, xantonas, triterpenoides, esteroides livres, saponinas e fenois. O teor de fenois totais tambem foi realizado utilizando-se o metodo de Folin-Ciocalteu cujo resultado foi maior na FAE (527,71 ¡Ó 30,80 mg de EAG.g-1). Para avaliar a atividade antioxidante foram utilizados os metodos de sequestro do radical livre (2,2-difenil-1-picril-hidrazil-DPPH) e da inibicao da lipoperoxidacao quantificada por meio das substancias reativas ao acido tiobarbiturico (TBARS). O EHE e as FAE e FHM tiveram um maior percentual de inibicao do radical livre DPPH com indices de 95,84%, 94,66% e 95,40% respectivamente. O EHE e FAE mostraram maior percentual de inibicao da peroxidacao lipidica quando induzida por AAPH enquanto a FHM, maior quando induzida por FeSO4. A atividade biologica investigada foi a anti-inflamatoria por meio da reducao do edema de orelha e pela atividade da mieloperoxidase (MPO). O edema de orelha foi induzido pelo 12-O-tetradecanoilforbol acetato (TPA, 1 Ýg/orelha) e o efeito do EHE ou das fracoes foi avaliado pela coadministracao dos mesmos, em doses de 1,0 e 3,0 mg/orelha, com o TPA na orelha direita. Na orelha esquerda foi administrado apenas o veiculo (acetona). Apos 6 h, os sitios de orelha foram retirados o edema expresso pela variacao da massa da orelha direita pela orelha esquerda, bem como a atividade de mieloperoxidase (MPO) foi mensurada. A coadministracao do EHE causou inibicao significativa (p<0,001) do edema e da atividade de MPO (p<0,05) em ambas as doses. Por sua vez, FHX, FCL, FAE e FHM reduziram o edema de forma semelhante na dose de 3,0 mg/orelha com percentuais de inibicao de 78%, 71%, 75% e 65%, respectivamente. A FAE e a FHM inibiram a atividade de MPO nas doses de 1,0 ou 3,0 mg/orelha (86% e 93% para 1,0 e 3,0 mg/orelha de FAE, respectivamente,p<0,001; 40% e 52% para 1,0 ou 3,0 mg/orelha de FHM respectivamente, p<0,05). A FCL causou inibicao apenas na dose de 3,0 mg/orelha (72%, p<0,05) e a FHX nao alterou significativamente a atividade de MPO induzida pelo TPA. Se considerados conjuntamente estes resultados indicam que o EHE e suas fracoes possuem acao antioxidante e anti-inflamatoria, viabilizando estudos futuros com esta planta para a obtencao de compostos bioativos.
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Bittencourt, Henrique von Hertwig. "Ecologia da germinação e potencial alelopático de capim-annoni-2 (Eragrostis plana Nees)". Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2379.
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A invasibilidade do capim-annoni-2 em agroecossistemas tem sido atribuída as suas características biológicas e relações ecológicas. A ecologia da germinação da espécie e a interação alelopática são pouco compreendidas. Este trabalho objetivou determinar a influência de fatores ambientais na germinação, a fitotoxicidade de extratos de capim-annoni-2, identificar e quantificar aleloquímicos fenólicos presentes em suas frações, determinar a influência da degradação da fitomassa e do solo na fitotoxicidade do extrato aquoso, monitorar a degradação dos compostos presentes nos extratos e identificar e quantificar aleloquímicos no solo de área contaminada. Foram realizados experimentos em laboratório utilizando materiais coletados a campo. As sementes germinaram em temperaturas constantes de 15 até 40 °C, mas as percentagens de germinação foram superiores a 94 % apenas em temperaturas alternadas. A exposição à luz aumentou a frequência de plântulas normais. A germinação aumentou com incremento no potencial de água e o número de plantas normais diminuiu com aumento na concentração de cloreto de sódio. A maior taxa de emergência foi observada com as sementes colocadas na superfície do solo, enquanto que nenhuma emergência ocorreu a 4 cm. Foram identificados e quantificados nove compostos fenólicos com potencial aleloquímico nas frações dos extratos de capim-annoni-2: ácido caféico, ácido cumárico, ácido ferúlico, ácido gálico, ácido vanílico, catequina, epicatequina, resveratrol e rutina. A ordem decrescente de fitotoxicidade geral dos extratos brutos no desenvolvimento de plântulas de trigo e alfafa foi acetato de etila, metanólico, aquoso e hexânico. Foi identificada correlação inversamente proporcional entre concentração de ácido vanílico e comprimento de radícula e total de plântulas de alfafa. A simulação da degradação da fitomassa e do solo ocasionou aumento na fitotoxicidade dos extratos sobre a germinação e o desenvolvimento de plântulas, comprovando a liberação dos aleloquímicos e a influência do solo no aumento de sua fitotoxicidade. Extratos etéreos da fitomassa e do solo incubados apresentaram modificações em seus respectivos cromatogramas do primeiro até o sétimo dia de incubação, enquanto a mistura de fitomassa + solo apresentou maiores modificações apenas entre o primeiro e o terceiro dia de degradação. Foram identificados quatro compostos fenólicos com potencial aleloquímico no solo da área infestada com capim-annoni-2: ácido cumárico, ácido ferúlico, catequina e epicatequina. A concentração destes compostos foi maior na superfície do solo e horizontalmente próximo às plantas de capim-annoni-2, evidenciando associação entre as concentrações dos aleloquímicos com a proximidade da planta.The invasiveness of South African lovegrass in agroecosystems has been attributed to its biological characteristics and the ecological relations. The ecology of species germination and allelopathic interaction are poorly understood. The objective of this work was to determine the influence of environmental factors on germination, phytotoxicity of South African lovegrass extracts, to identify and quantify phenolic allelochemicals present in their fractions, to determine the influence of phytomass and soil degradation on the phytotoxicity of the aqueous extract, to monitor the degradation of the compounds present in the extracts and to identify and quantify allelochemicals in a infested soil. Experiments were carried out in the laboratory using materials collected in the field. Seeds germinated at constant temperatures of 15 to 40 ° C, but the percentages of germination were greater than 94 % only at alternating temperatures. Exposure to light increased the frequency of normal seedlings. Germination increased with increasing water potential and the number of normal plants decreased with increasing sodium chloride concentration. The highest emergence rate was observed with the seeds placed on the soil surface, whereas no emergence occurred at 4 cm. A total of nine phenolic compounds with allelochemical potential were identified in the fractions of extracts of South African lovegrass: caffeic acid, coumaric acid, ferulic acid, gallic acid, vanillic acid, catechin, epicatechin, resveratrol and rutin. The general decreasing order of general phytotoxicity of crude extracts in the development of wheat and alfalfa seedlings was ethyl, methanolic, aqueous and hexane acetate. An inversely proportional correlation was identified between vanillic acid concentration and root and total alfalfa seedlings length. The simulation of phytomass and soil degradation caused an increase in the phytotoxicity of the extracts on germination and seedling development, proving the release of the allelochemicals and the influence of the soil in the increase of its phytotoxicity. The ether extracts of the straw and soil showed changes in their chromatograms from the first to the seventh day of incubation, while the mixture of straw + soil showed greater changes only between the first and third day of degradation. Four phenolic compounds with allelochemical potential were identified in the South African lovegrass infested soil: coumaric acid, ferulic acid, catechin and epicatechin. The concentration of these compounds was higher at the soil surface and horizontally near the South African lovegrass plants, showing an association between concentrations of allelochemicals and plant distance.
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Paano, AMC. "Phenethylisoquinoline - derived alkaloids and related systems". Thesis, 1986. https://eprints.utas.edu.au/21115/1/whole_PaanoAnamyMariaCaterial1987_thesis.pdf.
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The phenethylisoquinoline alkaloids comprise a relatively new class of alkaloids. They are structurally related to the very vast group of alkaloids based on the 1-benzylisoquinoline skeleton. Most of these alkaloids follow a biosynthetic pathway analogous to the benzylisoquinoline series. That is, they are biosynthesized from the 1-phenethylisoquinoline autumnaline (Table 1, A-1) and its relatives by phenolic oxidative coupling and subsequent reactions. At present, nine groups of alkaloids are identified as of the phenethylisoquinoline type (Scheme 1). This includes the simple 1-phenethylisoquinoline (1), homomorphinane (2), colchicine (3), homoproaporphine (4), homoaporphine (5), bisphenethylisoquinoline (6), dibenz[d,fJazecine (7), homoerythrina (8), and cephalotaxine (9) groups. The bold lines in Scheme 1 represent biosynthetic pathways indicated by tracer studies. No tracer studies have been done on those shown with dotted lines. One can see in the Scheme that, biosynthetically, homoerythrina and cephalotaxinemay be related by a common precursor, the dibenz[d,fJazecine-type alkaloid (7). Colchicine on the other hand is derived biosynthetically from a homomorphinane (2), specifically Q-methylandrocymbine (Table 1, C-2).
The homoprotoberberine-type alkaloid skeleton (10), which may also be biosynthetically derived from a 1-phenethylisoquinoline precursor by a Mannich-type reaction, and which was anticipated by Battersby to occur in plants, has not yet been isolated. However, a homoprotoberberine (11) was isolated from Berberis acticantha but differs from (10) in the ring C structure. That is, nitrogen and ring D are joined together by an ethylene group in (11) instead of a methylene group as in (10), the latter being characteristic of a Mannich-type ring closure. A complete list of the phenethyli soquinoline-derived alkaloids from plants, their sources, and their physical properties is given in Table 1 and summarised in Table 2. All the isolated alkaloids presented in Kamentani's review are included in Table 1 to provide a better view of the alkaloid profile.
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Paano, AMC. "Studies on dibenz(d,f)azecine and other phenethylisoquinoline-derived alkaloids". Thesis, 1992. https://eprints.utas.edu.au/21116/1/whole_PaanoAnamyMariaCaterial1992_thesis.pdf.
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The initial goal of this study was to develop a targetted and systematic search method for new examples of the known groups of phenethylisoquinoline-derived alkaloids with special emphasis on the least represented group, the dibenz[d,f]azecines. A considerable part of the work was devoted to the successful development of a search procedure using the combined gas chromatography-mass spectrometry (GC-MS) technique as the main tool. This included establishing working parameters for the GC-MS screening of this family of alkaloids; synthesizing some dibenz[d,f] azecines from possible new sources; and re-screening some known sources, with special attention being given to the minor components.
Re-screening of Dysoxylum lenticellare, the only reported source of a naturally occurring dibenz[d,f]azecine alkaloid, along with six other species of Dysoxylum showed the absence of dibenz[d,f]azecines and other phenethylisoquinoline-derived bases. Doubts have now been raised as to the actual identity of the plant. Athrotaxis selaginoides, a homoerythrina-containing plant species, was shown to contain an extremely minor component of a dibenz[d,f]azecine base. The very low concentration did not allow its isolation.
Attention was shifted to the Family Liliaceae, from which the majority of the reported phenethylisoquinoline-derived alkaloids have been isolated. Known phenethylisoquinoline-containing plants, and more than thirty other liliaceous species, were screened for dibenz[d,f]azecines. Their presence was detected only in species of Wurmbea and Baeometra.
At least eight new dibenz[d,f]azecine bases were detected and one named wurmbazecine, isolated pure from Wurmbea dioica ssp. dioica. The amount of this isolate limited the n.m.r. experiments that could be done on it leaving some ambiguity in its substitution pattern. Probable structures were therefore synthesized to confirm its structure, using the eliminative ring destruction approach from tetracyclic amino ketone precursors. A biogenesis of wurmbazecine is also proposed.
The conversion of the known homoerythrina alkaloid homoerythratine has led to the formation of some A-ring reduced dibenz[d,f]azecine derivatives whose mass spectral fragmentation patterns are distinct from those where the A-ring is oxidized.
As a result of the alkaloid screening work, over twelve new, as well as known, wurmbaeiodeae alkaloids such as the 1-
phenethylisoquinoline, homomorphines, homoaporphines, homoproaporphines, and colchicine-types from Wurmbea dioica ssp. dioica were isolated and their structures determined. Known alkaloids were also isolated from Gloriosa plantii, Wurmbea pygmaea, Baeometra uniflora and Colchicum autumnale. Other phenethylisoquinoline-type alkaloids were detected, but not isolated, from other plant species.
Twelve homoerythrina-type alkaloids were also isolated and characterized from the liliaceous plants Burchardia umbellata and Burchardia mu/tiflora as well as from Athrotaxis selaginoides (Taxodiaceae). The ring D modification of the two new bases isolated from Burchardia umbellata is the first of its kind; their structures were established by spectroscopic methods.
The search for the dibenz[d,f]azecine alkaloids from the family Liliaceae has allowed an in-depth study of the family's alkaloid profile. A summary of this is briefly discussed in the last discussion Chapter of the thesis, together with some possible chemotaxonomic implications.
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Wheeler, Peter John. "A kinetic and equilibrium study of rooibos tea infusions". Thesis, 1998. http://hdl.handle.net/10413/4755.
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The total mineral ion concentration of Rooibos Tea was determined using ICP-OES. Significant concentrations of Na, K, Mg, Ca, P were found, and trace levels of Al, Fe, Mo, Sr, Zn, Ba, Cu and Pb detected. Protocatechuic acid, aspalathin and rutin were identified in Rooibos tea infusions analysed with HPLC. Analysis of tea samples by Ion Chromatography showed the presence of Cr and S042- ions. Rooibos Tea liquor had a pH of 4.6 once equilibrium had been reached. Partition coefficients (1.0 - 1.4 mm sieving fraction) for Na+, K+, Mg2+, protocatechuic acid, aspalathin, rutin, S042- and Cl were determined for infusions at 80 C using a graphical and a successive extraction method. A total mineral content method was also used to determine the partition coefficients for the mineral ions. The Na+, K+, Mg2+,SO42-, H2P04- (as P) and Cl ions as well as protocatechuic acid,
aspalathin and rutin all displayed first order behavior, allowing the determination of infusion rate constants. The particle size effect was investigated at 80 C. All the mineral ions showed an increase in infusion rate constant with decreasing particle size, protocatechuic acid and aspalathin showed no trend, while the rutin infusion rate constant was independent of particle size. Calcium uptake by the leaf was observed, this was more pronounced with the smaller particle sizes. Infusion rate constants and hence diffusion coefficients were determined for the nine species for temperatures ranging from 45 to 90 C. These diffusion coefficients for the mineral ions were compared with those for the respective species in aqueous media to give hindrance factors, which were of the order of 102. Except for Cl, all hindrance factors increased with an increase in temperature. The infusion rate constants for all the species at the various temperatures were fitted to an Arrhenius equation and activation energies of infusion determined. The values were lower than those predicted theoretically.Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1998
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Horn, Marion Magdalena. "Muthi compounds from indigenous Lauraceae and Rubiaceae species". Thesis, 1996. http://hdl.handle.net/10413/8581.
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Panichanun, S. "Alkaloids of Athrotaxis species". Thesis, 1985. https://eprints.utas.edu.au/21132/1/whole_PanichanunSirichai1985_thesis.pdf.
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A detailed phytochemical examination of the alkaloid content of three species of the family Taxodiaceae, Athrotaxis cupressoides D. Don, Athrotaxis selaginoides D. Don, and Athrotaxis laxifolia Hook has been undertaken.
A total of twelve alkaloids were isolated; the alkaloids proved to have structures of the homoerythrina type, and included five known bases previously isolated from other plants. Spectroscopic and chemical evidence for the structures of the seven new alkaloids are presented in Chapter II.
The synthesis of the homoerythrina alkaloid skeleton has been attempted by two different approaches as presented in Chapter III, and the work done on homoerythrina alkaloids has been briefly reviewed in Chapter I.
Discaria toumatou and Discaria pubescens, members of the family Rhamnaceae, have been investigated. The alkaloids present were found to have the benzylisoquinoline type of structure, and the results appear in Chapter IV.
A preliminary investigation of Hypserpa veillardii, a species of the family Menispermaceae, has been made, and the results appear in Chapter V. The known bisbenzylisoquinoline alkaloid limacine was the only base to be isolated.