Segui questo link per vedere altri tipi di pubblicazioni sul tema: Tannin.
Articoli di riviste sul tema "Tannin"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-50 articoli di riviste per l'attività di ricerca sul tema "Tannin".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi gli articoli di riviste di molte aree scientifiche e compila una bibliografia corretta.
1
Makkar, H. P. S., M. Blümmel e K. Becker. "Formation of complexes between polyvinyl pyrrolidones or polyethylene glycols and tannins, and their implication in gas production and true digestibility in in vitro techniques". British Journal of Nutrition 73, n. 6 (giugno 1995): 897–913. http://dx.doi.org/10.1079/bjn19950095.
Testo completoAbstract (sommario):
Various tannin-complexing agentsw have been used to study the potential adverse effects of tannis on rumen metabolism. Using a method based on turbidity formation, the binding of various tannin-complexing agents (polyvinyl polypyrrolidone (PVPP), polyethylene glycol (PEG) of molecular weights 2000 to 35000, and polyvinyl pyrrolidone (PVP) of molecular weight 10000, 40000 and 360000) to tannins (tannic acid, purified tannins from quebracho (Aspidosperma quebracho) and leaves of trees and shrubs (Acioa barteri, Dichostachys cinerea, Guiera senegalensis, Piliostigma reticulatum)) was investigated at different pH values. The binding of all the tannins with PVPP was highest at pH 3–4 and lowest at pH 7. For all the pH range (3–7) studied, the binding of PEG was higher than that of PVP. For all the tannins except tannic acid, the binding to PVP was the same from pH 4·7 to 7. Similar results were observed for the PEG of molecular weight 6000 or higher for all the tannins except quebracho tannins for which the binding increased as the pH increased from 3 to 7. The binding with PEG 2000 decreased to a greater extent as the pH reached near neutral and for PEG 4000 this decrease was slightly lower. Addition of these tannin-complexing agents to the in vitro gas system resulted in higher gas production from tannin-rich feeds (increase varied from 0 to 135%). The PEG were the most effective followed by PVP and PVPP. The PEG 35000 was least effective. The efficiency of other PEG was similar. The PEG 6000 was preferred to PEG 2000 or 4000 as its binding to tannins was higher at near neutral pH values. The gas production increased with an increase in the amount of PEG 6000 up to 0·6 g/40 ml rumen-fluid-containing medium containing 0·5 g tannin-rich feed, beyond which no increase was observed. The percentage increase in gas value at 24 h fermentation correlated significantly with tannin values, the highest correlation (r 0·95) being with protein precipitation capacity of tannins. The increase in gas production was associated with higher production of short-chain fatty acids with little change in their molar proportions, suggesting an increase in organic matter digestibility by inclusion of the PEG in tannin-rich feeds. However, apparent and true digestibilities were lower on addition of the PEG, due to the presence of PEG-tannin complexes in the residues. The use of this bioassay (percentage increase in gas production in the presence of PEG 6000) along with other tannin assays would provide a better insight into the nutritional significance of tannins.
2
Yan, Q., e A. Bennick. "Identification of histatins as tannin-binding proteins in human saliva". Biochemical Journal 311, n. 1 (1 ottobre 1995): 341–47. http://dx.doi.org/10.1042/bj3110341.
Testo completoAbstract (sommario):
Tannins have a number of detrimental biological effects and these include interference with normal growth and metabolism if they are present in the feed of various animals. Proline-rich proteins (PRPs) in saliva have been shown to provide protection against tannin, but little is known about the mechanism of protection and interaction of other salivary proteins with tannin. To identify tannin-binding human salivary proteins, parotid and submandibular/sublingual saliva samples were adsorbed with tannin. PRPs, and in particular a group of low-M(r) proteins, were readily precipitated by tannin. The low-M(r) proteins were purified from parotid saliva and demonstrated to be histatins, a family of well-characterized histidine-rich salivary proteins. The ability of synthetic histatin 5, as well as an acidic PRP (PRP-1) and gelatin to precipitate quebracho condensed tannin and tannic acid was determined. At pH 7.4 histatin 5 was the most effective precipitant of both condensed tannin and tannic acid and it also precipitated the largest amount of condensed tannin at pH 3.0, but the smallest amount of tannic acid at that pH. In contrast PRP-1 showed a greater ability to precipitate both condensed tannin and tannic acid at pH 3.0 than at pH 7.4. Under most circumstances histatin 5 was therefore more effective in precipitating tannins than proteins with high proline content which generally have been recognized as strong precipitants of tannin. Pre-incubation of tannic acid with alpha-amylase inhibited the enzyme, but addition of histatin 5 or the acidic PRP PIF-s protected amylase from inhibition by tannin. Similarly salivary proteins may protect other biological activities in the digestive tract from inhibition by dietary tannin.
3
Frank Mayer. "Tannins: Natural plant-derived polyhydroxy phenolic compounds with potential for biotechnological and biomedical applications". World Journal of Biological and Pharmaceutical Research 2, n. 1 (30 gennaio 2022): 001–4. http://dx.doi.org/10.53346/wjbpr.2022.2.1.0127.
Testo completoAbstract (sommario):
The difference between Tannin and Tannic Acid is that the term Tannin is used to name the group of organic compounds whereas Tannic acid is a type of tannin. Members of the group of Tannins - all of them polyhydroxyphenolic compounds – are present in leaves and other nutrient-rich parts of a huge number of Angiosperm plants. In nature, Tannins play a significant role in the protection of the plants against herbivores. Tannins inactivate enzymes in the digestive tract of the herbivores, with respective consequences: the herbivores may die of starvation. A well-known example for a technological application of Tannins is the process of leather production. Complex formation with collagen the denaturation of proteins - here in the animal skin - by the polyhydroxyphenol components of Tannin is their major function. Various biomedical applications are known, such as application of Tannins due to their adstringent property, production of tannate salts, antihistamines and antitussive drugs. Recently, it was discovered that Tannic acid suppresses the virus SARS-CIY-2 as a dual inhibitor of the main viral protease and the cellular TMPRSS 2 protein, with the consequence that the virus cannot infect human cells.
4
Mutiar, Sri, e Anwar Kasim. "Potential and Application of Vegetable Tanning Materials from Industrial Forest Plantation in Indonesia". Journal of Fibers and Polymer Composites 2, n. 1 (31 marzo 2023): 29–45. http://dx.doi.org/10.55043/jfpc.v2i1.62.
Testo completoAbstract (sommario):
Vegetable tanning materials are sourced from plants that contain tannin compounds. Tannins are obtained through the extraction method from the roots, stems, bark, or fruit of the original plant. There are several forest management companies in Indonesia that produce wood from plant species Acacia auriculiformis and Acacia mangium. Both species are known as Acacia. Acacia is an important source of tannin for material tanner vegetables. This wood is produced as a raw material for the pulp and paper industry. However, the bark contains tannin and has not been used optimally. Therefore, the study's potential and possible applications as vegetable tanning agents have been carried out. The research was started by investigating the availability of bark and extracting tannins to obtain extracts containing tannins. Furthermore, the extract obtained was applied as a vegetable tanning agent for the goatskin tanning process. The results showed that the bark of the Plant Industry Forest has the potential to be developed as a source of tannins for material vegetable tanning agents. The application of acacia bark extract in goatskin tanning has obtained tanned leather that meets the Indonesian National Standard.
5
Odenyo, A. A., e P. O. Osuji. "Tannin-tolerant ruminal bacteria from East African ruminants". Canadian Journal of Microbiology 44, n. 9 (1 settembre 1998): 905–9. http://dx.doi.org/10.1139/w98-073.
Testo completoAbstract (sommario):
Three strains of tannin-tolerant rumen bacteria were isolated from enrichment cultures of rumen microflora of sheep, goat, and antelope and established in medium containing high concentrations of crude tannin extract or tannic acid. These three strains (EAT2, ES3, and EG19), characterized as Selenomonas species, were curved rods, obligately anaerobic, Gram negative, highly motile, and grew in media containing 50 g of tannin extract/L and 50-70 g of tannic acid/L. Strain EAT2 was able to hydrolyze gallic acid, while strains ES3 and EG19 hydrolyzed tannic acid but not gallic acid. All isolates were able to grow in media containing up to 8 g of condensed tannins/L. Growth was very slow when soluble carbohydrate was not added to the medium.Key words: tannin, rumen, bacteria, tannic acid, gallic acid, Selenomonas.
6
Mutuku, Maxwell, Jackson Ombui e Arthur Onyuka. "Assessment of Coffee Pulp as a Potential Source of Tannins for Leather Processing". Textile & Leather Review 5 (17 marzo 2022): 132–46. http://dx.doi.org/10.31881/tlr.2021.31.
Testo completoAbstract (sommario):
The leather industry is experiencing environmental challenges due to pollution associated with chromium tanning. Vegetable tanning is considered as an ecofriendly alternative method. Previous research studies have established that coffee contains 1-10% of tannins. In this study coffee arabica pulp was determined for its tannin content and tanning strength for potential use as a source of tanning material. The hide powder method was used and the tannin content of coffee arabica pulp determined as 5.04% with the tanning strength of 2.26 compared to mimosa which had a tannin content of 63.56% with a tanning strength of 2.82. Both coffee arabica pulp and mimosa exceeded the 1.5 tanning strength recommended for tanning agents. It was concluded that coffee arabica pulp sufficient tanning strength to be used as a tanning material.
7
Nyaga, Mwenda, Paul Tanui e Samuel Njenga. "Evaluation of Tamarindus indica L. Seed Tannins". Textile & Leather Review 6 (18 agosto 2023): 373–86. http://dx.doi.org/10.31881/tlr.2023.081.
Testo completoAbstract (sommario):
Tannins are water-soluble polyphenols mostly found in vascular plants and are important raw materials in many industries like leather, pharmaceuticals, and food and beverages. Tannins protect the plant and help its growth. In this study, Tamarindus indica L. seeds were extracted for the determination of tannin content and the tanning strength by the hide powder method. Earlier studies showed that Tamarindus indica L. seeds varied in the amount of tannins present. Mimosa was used as a control. The tanning strength was 1.73 for the tamarind seed extract and 2.06 for mimosa. The tannin content was >10% for both the tamarind seed extract and mimosa. It was concluded that both tamarind seed extract and mimosa had sufficient tanning strength exceeding (1.5) the minimum recommended for a tanning agent hence providing insights as a feasible material for the tanning process.
8
Hernández, Mario Cruz, Juan Carlos Contreras Esquivel, Faustino Lara, Raúl Rodríguez e Cristóbal N. Aguilar. "Isolation and Evaluation of Tannin-degrading Fungal Strains from the Mexican Desert". Zeitschrift für Naturforschung C 60, n. 11-12 (1 dicembre 2005): 844–48. http://dx.doi.org/10.1515/znc-2005-11-1205.
Testo completoAbstract (sommario):
Eleven fungal strains (4 Penicillium commune, 2 Aspergillus niger, 2 Aspergillus rugulosa, Aspergillus terricola, Aspergillus ornatus and Aspergillus fumigatus) were isolated, characterized morphologically and by their capacity to degrade tannins. Aspergillus niger Aa-20 was used as control strain. Several concentrations of hydrolysable tannin (tannic acid) were used as sole carbon source. All strains were able to degrade hydrolysable tannins. Aspergillus niger GH1 and PSH showed the highest tannin-degrading capacity (67 and 70%, respectively). Also, the fungal capacity to degrade condensed tannin (catechin) was tested. Aspergillus niger PSH and Penicillium commune EH2 degraded 79.33% and 76.35% of catechin. The results demonstrated the capacity of fungi to use hydrolysable and condensed tannins as carbon source.
9
Lamy, E., E. S. Baptista, A. V. Coelho e F. Capela e. Silva. "Morphological alterations in salivary glands of mice (Mus musculus) submitted to tannin enriched diets: comparison with sialotrophic effects of sympathetic agonists stimulation". Arquivo Brasileiro de Medicina Veterinária e Zootecnia 62, n. 4 (agosto 2010): 837–44. http://dx.doi.org/10.1590/s0102-09352010000400012.
Testo completoAbstract (sommario):
In order to study the effects of tannins at histomorphological level, mice were either fed with three structurally different types of tannins (tannic acid, chestnut, and quebracho) or treated with isoproterenol, during 10 days. Acini of parotid and submandibular glands increased significantly, being the increase higher for parotid compared to submandibular glands, and higher in the quebracho compared with the other tannin groups. Sublingual acinar size also increased after tannin consumption, by opposition to isoproterenol-treated animals. The results present evidences that the effects produced by tannins are dependent on their structure.
10
Kusumo, Galuh Gondo, M. A. Hanny Ferry Fernanda e Heppy Asroriyah. "Identifikasi Senyawa Tanin Pada Daun Kemuning (Murraya panicullata L. Jack) Dengan Berbagai Jenis Pelarut Pengekstraksi". Journal of Pharmacy and Science 2, n. 1 (7 gennaio 2017): 29–32. http://dx.doi.org/10.53342/pharmasci.v2i1.63.
Testo completoAbstract (sommario):
ABSTRAKKemuning (Murraya paniculata L. Jack) adalah salah satu kekayaan alam yang memiliki banyak manfaat bagi kehidupan manusia. Tanin merupakan salah satu metabolit sekunder dari kemuning yang dapat digunakan sebagai anti diare dan pelangsing. Ekstrak kemuning didapatkan dari maserasi menggunakan tiga pelarut berbeda, yaitu metanol, etanol dan etil asetat. Tannin kemudian dipisahan dari ekstrak dengan menggunakan kromatografi lapis tipis (KLT) dengan berbagai jenis pelarut. Hasil nalisis menunjukkan bahwa pelarut terbaik untuk mengekstraksi tanin adalah metanol dengan perolehan 23,6989 g (31,59%). Skrining fitokimia yang dilakukan menggunakan dua reagen yang berbeda menunjukkan hasil yang positif mengandung tanin. Eluenterbaik untuk analisa tanin pada penelitian ini adalah dengan n-heksan-etil asetat (6 : 4) dengan nilai Rf sebesar 0,62.Kata Kunci : kemuning (Murraya paniculata L. Jack), tannin, kromatografi lapis tipis (KLT)ABSTRACTOrange Jessamine (Murraya paniculata L. Jack) is one of the natural treasures which has many benefits for human life. Tannin is one of secondary metabolite of orange jessamine that can be used as antidiarrhoeal and body slimming. It was obtained by maceration using 3 different solvents, such as : methanol, ethanol, and ethyl acetate. Tannins was separated from crude extract using thin layer chromatography (TLC) in different type of eluent. The analysis showed that the best solvent to extract tannin is methanol that produce of 23.6989 g (31.59%). The phytochemical screening test of the two reagents shows positif result contain tannin compound. The best eluent in this study aimed is n-hexane: ethyl acetate (6 : 4) with tannin Rf value of 0.62.Keywords: Orange jessamine (Murraya paniculata L. Jack), tannin, maceration, thin layer chromatography
11
Donald Mudenda Chisowa. "Comparative evaluation of the effect of boiling and autoclaving of legume grains on tannin concentration". Magna Scientia Advanced Biology and Pharmacy 7, n. 1 (30 settembre 2022): 009–17. http://dx.doi.org/10.30574/msabp.2022.7.1.0080.
Testo completoAbstract (sommario):
The study was designed to evaluate the effect of boiling and microwave treatment methods on reducing the concentration of tannins in Soy bean (Sb), Cowpea (Cp) and Pigeon pea (Pg) legume grains (LGs). The raw samples of LGs were roasted in a microwave oven for 3 and 6 minutes at 120 Three (3) LG seeds weighing 30 gms were boiled for 30 and 60 minutes in water at 100 oC. Meals of Raw, boiled and microwaved Sb, Pp and Cp LGs were subjected to proximate analysis for levels of tannins using the Folin-Ciocalteu assay technique. Absorbance for each sample as indicator of tannin concentration was read from UV-VSI spectrophotometer. Tannic acid levels in micrograms for the three (3) samples were read from the standard curve and the tannin content was calculated as on dry matter basis. Raw samples showed no significant (p<0.01) difference in tannin content in Sb, Cp and Pp. Boiling the LGs in water for 30 minutes resulted in the reduction of tannin up to 46.6% Sb, 53.5% Pp and 42.5% Cp. Boiling for 60 minutes resulted in the reduction of tannins to 62.5 % Sb, 72.9% Pp and 75% Cp respectively. Microwaving the LGs for 3 minutes resulted in 46.7% Sb, 54.2 % Pp and 37.5% Cp reduction of tannin levels respectively. Microwaving for 6 minutes reduced tannins by 71.1% in Sb, 65.1% in Pp and 65% in Cp. No tannin significant (p˂0.05) difference was observed for the effect of boiling and microwave treatment LGs.
12
Santos, José Danrley Cavalcante dos, Edilson Paes Saraiva, Severino Gonzaga Neto, Carla Aparecida Soares Saraiva, Antônio da Costa Pinheiro, Vinícius de França Carvalho Fonsêca, Severino Guilherme Caetano Gonçalves dos Santos et al. "Feeding Behavior of Lactating Dairy Cattle Fed Sorghum-Based Diets and Increasing Levels of Tannic Acid". Agriculture 11, n. 2 (20 febbraio 2021): 172. http://dx.doi.org/10.3390/agriculture11020172.
Testo completoAbstract (sommario):
Tannins have been used to trigger positive effects on ruminal metabolism and increase ruminant production efficiency, since they increase the supply of dietary protein in the small intestine. Increasing levels of tannic acid in a sorghum-based diet on the feeding behavior of five Holstein/Zebu crossbred lactating dairy cows was evaluated. They were subjected to a 5 × 5 Latin square experimental design, with fivelevels of tannin as dry matter (DM) in the diet (0.46, 1.30, 2.60, 3.90, and 5.20%). The levels of the tannic acid added were established based on the quantity of condensed tannin in high-tannin sorghum. Thus, diets 2, 3, 4 and 5 were supplemented with 1.5 g (13% DM), 79.5 g (2.6% DM), 157.5 g (3.9% DM), and 235.5 g (5.2% DM) of tannic acid, totaling 0.078, 0.156, 0.234, and 0.321 kg of tannin/day, respectively. Feeding behavior variables included the following states and events: feeding, drinking, rumination, and inactivity; the frequency of visiting the feed and water troughs; and the occurrence of urination and defecation. Water was provided ad libitum, and its intake was measured during periods of behavioral data collection. The use of two tannin sources (hydrolysable and condensed) corresponding to the total level of 5.20% (on a DM basis) in the diet of lactating dairy cattle does not affect the animals’ health. Tannic acid can be included in the diet of lactating dairy cattle at a level of 3.93% (on a DM basis) without inducing variation in the total time spent daily on feed intake. Dairy cows dilute the effects of dietary tannin (5.20%) through greater fragmentation of food consumption in the hours following its supply (180 min). The astringent effects caused by tannin intake in lactating dairy cows are mitigated by increasing the daily water intake as the amount of tannin in the diet increases, starting at a level of 3.90% tannin (on a DM basis).
13
Petchidurai, Ganeshan, Kitherian Sahayaraj, Laila A. Al-Shuraym, Bader Z. Albogami e Samy M. Sayed. "Insecticidal Activity of Tannins from Selected Brown Macroalgae against the Cotton Leafhopper Amrasca devastans". Plants 12, n. 18 (6 settembre 2023): 3188. http://dx.doi.org/10.3390/plants12183188.
Testo completoAbstract (sommario):
Seaweeds, also known as marine macroalgae, are renewable biological resources that are found worldwide and possess a wide variety of secondary metabolites, including tannins. Drifted brown seaweed (DBSW) is particularly rich in tannins and is regarded as biological trash. The cotton leaf hopper Amrasca devastans (Distant) has caused both quantitative and qualitative losses in cotton production. Drifted brown seaweeds (DBSWs) were used in this study to extract, qualitatively profile, and quantify the levels of total tannins, condensed tannins, hydrolyzable tannins, and phlorotannins in the seaweeds; test their insecticidal activity; and determine the mechanism of action. The largest amount of tannin extract was found in Sargassum wightii Greville (20.62%) using the Soxhlet method (SM). Significantly higher amounts of hydrolyzable tannins (p = 0.005), soluble phlorotannins (p = 0.005), total tannins in the SM (p = 0.003), and total tannins in the cold percolation method (p = 0.005) were recorded in S. wightii. However, high levels of condensed tannins (CTAs) were observed in Turbinaria ornata (Turner) J. Agardh (p = 0.004). A. devastans nymphs and adults were examined for oral toxicity (OT) and contact toxicity (CT) against DBSW tannin crude extract and column chromatographic fractions 1 (Rf = 0.86) and 2 (Rf = 0.88). Stoechospermum polypodioides (J.V. Lamouroux) J. Agardh crude tannin was highly effective against A. devastans using the OT method (LC50, 0.044%) when compared with the standard gallic acid (LC50, 0.044%) and tannic acid (LC50, 0.122%). Similarly, S. wightii fraction 2 (LC50, 0.007%) showed a greater insecticidal effect against A. devastans adults in OT than gallic acid (LC50, 0.034%) and tannic acid (LC50, 0.022%). The mechanism of action results show that A. devastans adults treated with crude tannin of T. ornata had significantly decreased amylase, protease (p = 0.005), and invertase (p = 0.003) levels when compared with the detoxification enzymes. The levels of glycosidase, lactate dehydrogenase, esterase, lipase, invertase, and acid phosphate activities (p = 0.005) of S. wightii were reduced when compared with those of the Vijayneem and chemical pesticide Monocrotophos. In adult insects treated with LC50 concentrations of S. wightii tannin fraction 1, the total body protein (9.00 µg/µL) was significantly reduced (OT, LC50—0.019%). The SDS-PAGE analysis results also show that S. wightii tannin fraction 1 (OT and CT), fraction 2 (OT), and S. polypodioides fraction 2 (CT) had a significant effect on the total body portion level, appearance, and disappearance of some proteins and polypeptides. This study shows that the selected brown macroalgae can be utilized for the safer management of cotton leaf hoppers.
14
Khan, Shahid Rehman, Shahzad Maqsood Khan e Rafi Ullah Khan. "Eco-Friendly Valorization and Utilization of Plant Waste as a Source of Tannin for Leather Tanning". Sustainability 15, n. 5 (21 febbraio 2023): 3884. http://dx.doi.org/10.3390/su15053884.
Testo completoAbstract (sommario):
In the present study, bark, which is the waste part of a tree, was utilized as a source of tannin for leather tanning after its value addition. The barks of Acacia nilotica L. and Eucalyptus globulus, which are abundantly available in Pakistan, were selected in this study. Different extraction techniques including mechanical, soxhlet, reflux and ultrasonic extraction were used for the extraction of tannin from the selected barks. The medium of extraction included aqueous as well as different solvent mixtures in different ratios. The solvent mixtures used in this study were methanol-water and acetone–water. The methanol–water ratio was kept (50:50) and the acetone–water ratio was maintained at (50:50 and 70:30). In the first step, the process of extraction was optimized for solvent mixtures and extraction time by taking a fixed dose (5 g) of each bark and a fixed volume of each extracting solvent mixture (150 mL). The total phenolic contents (TPC) of the bark extracts were determined by colorimetric assay (as mg GAE/g bark), taking gallic acid as the reference standard. The tannin contents (TC) of the bark extracts were determined by using the standard hide powder method (SLC 117). It was concluded that among the different extraction techniques, and among the solvent mixtures acetone–water in ratio (70:30), ultrasonic extraction resulted in maximum extraction of tannin (196.1 and 125.2 mg/g), respectively for A. nilotica and E. globulus. FTIR analyses of the dried extracts obtained from both barks were compared with FTIR of the most commonly used commercial vegetable tanning agent in the leather industry, i.e., mimosa. Results were comparable, which confirmed the presence of condensed tannin in both barks. The extracted tannin was applied on a pickle and wet blue leather to evaluate its tanning and re-tanning capability. Mimosa, the most abundantly used vegetable tanning material in the leather industry, was applied as a reference standard on the same pickle and wet blue leather for comparison. Different physical properties, such as leather shrinkage temperature, leather softness, tensile strength, percent elongation and breaking strength, were measured to evaluate the tanning efficacy of the extracted tannins. The results showed that tannin obtained from A. nilotica showed comparable physical properties to those of mimosa. It was concluded from the results that tannin obtained from locally available bark, i.e., A. nilotica, can be utilized as a vegetable tanning agent for the leather industry.
15
Souza, Carla Giselly de, Severino Gonzaga Neto, Lara Toledo Henriques, Gherman Garcia Leal Araújo, Luciana Thie Seki Dias e Ana Jaqueline Cavalcante Muniz. "Performance and blood parameters of Holstein/Zebu crossbred heifers fed with two tannins sources". Research, Society and Development 9, n. 2 (1 gennaio 2020): e128922150. http://dx.doi.org/10.33448/rsd-v9i2.2150.
Testo completoAbstract (sommario):
The present research objective was to evaluate the performance and blood parameters of lactating cows fed with a diet of two tannin sources, based on sorghum (condensed tannin) with increasing concentrations of tannic acid (hydrolyzable tannin’s). Increasing levels of tannic acid in a sorghum-based diet for five Holstein/Zebu crossbred lactating cows were subject to a 5 × 5 Latin square experimental design. To assess the effect on cow intake, digestibility, milk production, and blood parameters. All cows received 9.87 kg/DM of corn silage as roughage and 6.38 kg of concentrate consisting of 2.58 kg/DM of ground sorghum 0.87 kg/DM of cornmeal 1.32 kg/DM of soybean bran 0.44 kg/DM of wheat bran 0.2 kg/ DM of urea and 0.18 kg/ DM of mineral mixture. Diet 1 (control) contained low-tannin sorghum and the other diets contained high-tannin sorghum. The levels of tannic acid added to the diets were established based on the quantity of condensed tannin in high-tannin sorghum. Thus, diets 2, 3, 4 and 5 were supplemented with 1.5g (13.%DM), 79.5g (2.6%DM), 157.5g (3.9%DM) and 235.5g (5.2%DM) of tannic acid, totalling 0.078, 0.156, 0.234 and 0.321 total tannin kg/day respectively, to assess the effect on microbial protein synthesis. The diets contained 35 kg of corn silage (roughage) and 6.40 kg of concentrate. The natural and dry matter intake did not significantly differ between groups, except for ether extract (EE) intake that significantly differed. The DM apparent digestibility, crude protein, EE, neutral detergent fiber, total carbohydrate, and non-fibrous carbohydrate did not differ (P > 0.05) with the increase in dietary tannin supplementation. The GOT levels increased linearly. The blood glucose, triglyceride, and cholesterol (total, LDL and HDL) levels did not significantly differ. Hemoglobin showed a significant difference. No significant difference in urea, creatinine and uric acid occurred. Diets using two tannins sources supplementation caused no decrease in the dietary intake or digestibility in the animals. The GOT level changed significantly, showing linear behavior, however below the toxicity level, without any change in the other blood parameters. Milk production decreased with the increase in dietary tannin supplementation.
16
Yang, Tao, Mengqi Dong, Juqing Cui, Lu Gan e Shuguang Han. "Exploring the formaldehyde reactivity of tannins with different molecular weight distributions: bayberry tannins and larch tannins". Holzforschung 74, n. 7 (28 luglio 2020): 673–82. http://dx.doi.org/10.1515/hf-2019-0050.
Testo completoAbstract (sommario):
AbstractIn recent years, tannin degradation has been used to obtain tannin materials with an optimal molecular weight distribution (MWD) for synthesizing tannin-formaldehyde (TF) resin with high performance, but the optimal MWD of tannins is still unknown. The excellent formaldehyde reactivity of tannins is the basis for the synthesis of high-performance TF resin. Based on the formaldehyde reactivity of tannins, bayberry tannins and larch tannins were used to explore the optimal MWD of tannins for TF resin synthesis. Progressive solvent precipitation (PSP) was used to obtain tannin fractions with different MWDs. The formaldehyde reactivity of tannins was determined using the modified Stiansy method combined with the standard curve method (GB/T 17657-2013). The bayberry tannin fraction [weight-average molecular weight (Mw) of acetylated tannin: 4115, mean degree of polymerization (mDP): 6.64] and the larch tannin fraction (Mw of acetylated tannin: 3906, mDP: 5.84) had the best formaldehyde reactivity. Furthermore, significant differences in the formaldehyde reactivity of condensed tannins (CTs) with different MWDs were observed. The obtained results can be used to purposefully degrade tannins to achieve an optimal MWD, which is beneficial for the production of TF adhesives with high performance.
17
Ozkan, Cigdem Kilicarislan. "Tanning with Pomegranate Peel Tannin". Journal of the American Leather Chemists Association 118, n. 7 (3 luglio 2023): 301–6. http://dx.doi.org/10.34314/jalca.v118i7.7860.
Testo completoAbstract (sommario):
By-products of pomegranate juice enterprises are evaluated as a “green” raw material for many industries. In this study, pomegranate peels which are well known with high polyphenolic content were evaluated as a potential source of tanning agent for leather industry. For this purpose, firstly pomegranate peels were extracted in Koch extractor at 70°C for 8 hours. In order to determine the tanning ability, 30% of ground pomegranate peel powder (containing 7.2% of active tannin matter) was used in the tanning process and pomegranate peel tanned leather was evaluated in terms of increases in thickness and shrinkage temperature, color change and mechanical properties. The application of pomegranate peel tannin in the tanning process provided that an acceptable shrinkage temperature (68.5°C) and mechanical properties for vegetable tanned leathers. The results revealed that the tannin obtained from pomegranate peel has a remarkable tanning effect and can be used in the tanning process. Thus, it is concluded that pomegranate peels can be evaluated as a new source of tannin for leather industry.
18
Arcuri, Pedro Braga, Michael Larry Thonney, Peter Schofield e Alice Nelson Pell. "Polyethylene glycol and polyvinylpirrolidone effect on bacterial rRNA extraction and hybridization from cells exposed to tannins". Pesquisa Agropecuária Brasileira 38, n. 9 (settembre 2003): 1073–81. http://dx.doi.org/10.1590/s0100-204x2003000900008.
Testo completoAbstract (sommario):
In order to detect fluctuations in ruminal microbial populations due to forage tannins using 16S ribosomal RNA (rRNA) probes, recovery of intact rRNA is required. The objective of this work was to evaluate the effect of polyethylene glycol (PEG) and polyvinylpirrolidone (PVP) on extraction of bacterial rRNA, in the presence of tannins from tropical legume forages and other sources, that hybridize with oligonucleotide probes. Ruminococcus albus 8 cells were exposed to 8 g/L tannic acid or 1 g/L condensed tannins extracted from Acacia angustissima, banana (Musa sp.) skin, Desmodium ovalifolium, red grape (Vitis vinifera) skin and Inga edulis, or no tannins. Cells were rinsed with Tris buffer pH 7 containing either 8% PEG or 6% PVP prior to cell lysis. Total RNA samples rinsed with either PEG or PVP migrated through denaturing agarose gels. The 16S rRNA bands successfully hybridized with a R. albus species-specific oligonucleotide probe, regardless of tannin source. The effect of rinsing buffers on the density of 16S rRNA bands, as well as on the hybridization signals was compared. There were significant effects (P<0.01) when the controls were compared to either buffer treatments due to tannin type, buffer used and the interaction of tannin type and buffer. The significant interaction indicates the influence of tannin type on the parameters evaluated.
19
Makkar, H. P. S., e K. Becker. "Adaptation of cattle to tannins: rôle of proline-rich proteins in oak-fed cattle". Animal Science 67, n. 2 (ottobre 1998): 277–81. http://dx.doi.org/10.1017/s1357729800010031.
Testo completoAbstract (sommario):
AbstractSaliva and faecal samples were collected from hill cattle (no. = 10) given tannin-rich oak (Quercus incana) leaves in the north-west Himalayan region of India. Amino acid composition of the saliva samples after thawing to remove precipitated proteins by centrifugation, and dialysis (molecular weight cut off: 3500) to remove small moieties revealed 6·4 (s.d. 0·6) % proline, 15·6 (s.d. 0·6) % glutamine plus glutamate and 9·2 (s.d. 1·0) % glycine on molar basis. For Holstein Friesian cattle (no. = 4) which had no history of consumption of tannin-containing foods, these values were 6·5 (s.d. 0·4) %, 15·2 (s.d. 0·5) % and 9·8 (s.d. 0·7) % respectively. Proline concentration in the proteins present either as free or as tannin-protein complexes in the lyophilized faecal samples from hill cattle was 4·7 (s.d. 0·2) % (on molar basis) of the total amino acids and 5·3 (s.d. 0·2) % in Holstein Friesian cattle. In the faeces of oak-fed cattle, the tannin and condensed tannin levels on dry-weight basis were 0·81 (s.d. 0·20) % as tannin acid equivalent and 0·06 (s.d. 0·04) % as leucocyanidin equivalent respectively. For tannic acid, the relative affinity of salivary proteins, using the competitive binding assay, was about six-times higher than that of bovine serum albumin (BSA) and was of the same order as that of gelatin. Turbidity of complexes formed between salivary proteins or BSA and tannic acid showed proportionately about 0·50 lower turbidity for salivary proteins in 0-2 mol/I acetate buffer (pH 4·9 containing 0·17 mol/l NaCl) and proportionately about 0·84 lower turbidity in distilled water. The results suggest that unlike rats or mice, the proline-rich proteins do not appear to be of any physiological significance in the adaptation of cattle to tannins. However, the salivary proteins of cattle though not rich in proline, have a high affinity for tannins and these proteins have a high tendency to form soluble tannin-protein complexes.
20
Gloria Susan, Cherian, e Raja Madhan. "Bacterial Degradation of Bacteriostatic Polyphenols, Tannins". Journal of Natural Products and Resources 7, n. 2 (31 ottobre 2021): 272–75. http://dx.doi.org/10.30799/jnpr.100.21070201.
Testo completoAbstract (sommario):
Tannin degradation by bacteria has not been studied much as tannins are commonly known to be bacteriostatic due to enzyme inhibition, substrate deprivation, and the enzyme activity on the bacterial cell wall. However, about a handful of bacteria have been found to tolerate certain concentrations of tannin. This study focuses on isolating and identifying bacteria from decaying portions of tree bark for tannase production and effective catalysis of ester bond hydrolysis in tannins. Different concentrations of commercial tannic acid were used as the sole carbon source on mineral salt medium (MSM) agar plates, to test the maximum tolerable concentrations (MTCs) by the isolates. Tannin degradation was confirmed by a visual reading method and bacterial tannase activity and the biodegradation percentage were determined. One particular isolate was identified to have 50 g/L MTC of tannin, with a tannase activity of 51.61 U/mL that is optimum after 96 hours of incubation. The 16s rRNA sequencing results showed that the isolate belonged to Bacillus genus and the resulting bacterial strain isolate was found to be a new strain of Bacillus subtilis which was submitted to GenBank under the accession number MH330408.
21
Štumpf, Sara, Gregor Hostnik, Mateja Primožič, Maja Leitgeb e Urban Bren. "Generation Times of E. coli Prolong with Increasing Tannin Concentration while the Lag Phase Extends Exponentially". Plants 9, n. 12 (1 dicembre 2020): 1680. http://dx.doi.org/10.3390/plants9121680.
Testo completoAbstract (sommario):
The current study examines the effect of tannins and tannin extracts on the lag phase duration, growth rate, and generation time of Escherichia coli. Effects of castalagin, vescalagin, gallic acid, Colistizer, tannic acid as well as chestnut, mimosa, and quebracho extracts were determined on E. coli’s growth phases using the broth microdilution method and obtained by turbidimetric measurements. E. coli responds to the stress caused by the investigated antimicrobial agents with reduced growth rates, longer generation times, and extended lag phases. Prolongation of the lag phase was relatively small at low tannin concentrations, while it became more pronounced at concentrations above half the MIC. Moreover, for the first time, it was observed that lag time extensions follow a strict exponential relationship with increasing tannin concentrations. This feature is very likely a direct consequence of the tannin complexation of certain essential ions from the growth medium, making them unavailable to E. coli for its growth.
22
Bobrov, Anatoly, Vasiliy D. Kravchenko e Günter C. Müller. "Tannin-degrading bacteria with cellulase activity isolated from the cecum of the Qinghai-Tibet plateau zokor (Myospalax baileyi)". Israel Journal of Ecology and Evolution 61, n. 1 (5 maggio 2015): 21–27. http://dx.doi.org/10.1080/15659801.2015.1016863.
Testo completoAbstract (sommario):
Tannins, which are polyphenols present in various plants, have anti-nutritional activity; however, their negative effects are mitigated by the presence of tannin-degrading microorganisms in the gastrointestinal tract of animals. This has never been investigated in the plateau zokor (Myospalax baileyi) – the predominant small herbivore in the alpine meadow ecosystem of Qinghai Province, China – which consumes tannin-rich herbaceous plants. Tannase activity in the feces of the plateau zokor increased from June to August corresponding to the increase in hydrolyzable tannin concentrations in plants during this period, and three tannin-degrading facultative anaerobic strains (designated as E1, E2, and E3) were isolated from the cecum of these animals. Sequencing of the 16S rDNA gene identified isolates of strain E1 as belonging to the genusEnterococcus, and E2 and E3 to the genusBacillus. All of the bacteria had cellulose-degrading capacity. This study provides the first evidence of symbiotic bacterial strains that degrade tannic acid and cellulose in the cecum of plateau zokor.
23
Frutos, P., G. Hervás, F. J. Giráldez e A. R. Mantecón. "An in vitro study on the ability of polyethylene glycol to inhibit the effect of quebracho tannins and tannic acid on rumen fermentation in sheep, goats, cows, and deer". Australian Journal of Agricultural Research 55, n. 11 (2004): 1125. http://dx.doi.org/10.1071/ar04058.
Testo completoAbstract (sommario):
Abstract. Batch cultures of rumen microorganisms, using rumen fluids from 4 ruminant species, sheep, goats, cows, and deer, were used to study the ability of polyethylene-glycol (PEG 6000) to inhibit the effect of 2 types of tannins, quebracho (QUE, a condensed tannin) and tannic acid (TA, a hydrolysable tannin) on several in vitro rumen fermentation characteristics. Both QUE and TA were able to impair ruminal fermentation (they reduced gas production, extent of degradation, ammonia-N, and volatile fatty acid concentrations, etc.; P < 0.05), with differences depending on the inoculum donor. The clearest effect of tannins was the reduction of the rates of fermentation, which was observed in all species (P < 0.05). The detrimental effects of tannins were removed by the presence of PEG in most cases, but there were important variations and noticeable exceptions. Thus, for instance, PEG failed to revert the negative effect of TA on the rate of fermentation and the extent of degradation (P < 0.05). The extent of the limited ability of PEG to completely inhibit the negative effects of tannins on in vitro ruminal fermentation seems to depend both on the type of tannin and the species of the rumen inoculum donor.
24
Smith, Alexandra H., e Roderick I. Mackie. "Effect of Condensed Tannins on Bacterial Diversity and Metabolic Activity in the Rat Gastrointestinal Tract". Applied and Environmental Microbiology 70, n. 2 (febbraio 2004): 1104–15. http://dx.doi.org/10.1128/aem.70.2.1104-1115.2004.
Testo completoAbstract (sommario):
ABSTRACT The effect of dietary condensed tannins (proanthocyanidins) on rat fecal bacterial populations was ascertained in order to determine whether the proportion on tannin-resistant bacteria increased and if there was a change in the predominant bacterial populations. After 3 weeks of tannin diets the proportion of tannin-resistant bacteria increased significantly (P < 0.05) from 0.3% ± 5.5% to 25.3% ± 8.3% with a 0.7% tannin diet and to 47.2% ± 5.1% with a 2% tannin diet. The proportion of tannin-resistant bacteria returned to preexposure levels in the absence of dietary tannins. A shift in bacterial populations was confirmed by molecular fingerprinting of fecal bacterial populations by denaturing gradient gel electrophoresis (DGGE). Posttreatment samples were generally still distinguishable from controls after 3.5 weeks. Sequence analysis of DGGE bands and characterization of tannin-resistant isolates indicated that tannins selected for Enterobacteriaceae and Bacteroides species. Dot blot quantification confirmed that these gram-negative bacterial groups predominated in the presence of dietary tannins and that there was a corresponding decrease in the gram-positive Clostridium leptum group and other groups. Metabolic fingerprint patterns revealed that functional activities of culturable fecal bacteria were affected by the presence of tannins. Condensed tannins of Acacia angustissima altered fecal bacterial populations in the rat gastrointestinal tract, resulting in a shift in the predominant bacteria towards tannin-resistant gram-negative Enterobacteriaceae and Bacteroides species.
25
Kurnianto, Afrizal Syifa, Anjasmara Wahyu Wicaksana, Muhammad Prima Putra, Ragil Yuliatmo e Mohammad Zainal Abidin. "Unveiling the Potential of Secang (Caesalpinia sappan L.) as a Novel Tanning Agent: A Promising Alternative for the Leather Industry". Textile & Leather Review 7 (16 febbraio 2024): 222–34. http://dx.doi.org/10.31881/tlr.2023.194.
Testo completoAbstract (sommario):
The exploration of vegetable tanning's natural resources is fascinating as an alternative to basic chromium sulfate for its natural abundance and considerable environmental impact. In this work, an attempt has been made to extract vegetable tannin from Caesalpinia sappan L. bark using water as a solvent with different levels of temperatures and incubation times. The highest yield efficiency was observed at 80 °C for 4 hours. The presence of tannin content and polyphenolic compounds were screened by the phytochemical analysis using Iron (III) chloride (FeCl3), sodium hydroxide (NaOH), and ensured by the thin layer chromatography (TLC), and the Fourier transform infrared (FTIR). The extracts were then determined by percentage of extract yield, phytochemical, tannin type, moisture, total solids, and tannin characteristics. The findings indicate that the extract of Secang contains 4.98±0.28% total moisture, 95.02 ± 0.28% total solids, and 72.12 ± 2.81% total soluble solids, 52.28 ± 1.79% tannins, and 19.84 ± 1.41% non-tannin. Moreover, Fourier transform infrared (FTIR) analysis revealed a clear functional group within Caesalpinia sappan L., as evidenced by the type of tannin that is condensed. The TLC assay exhibited a considerable intensity under UV lights. It included several shades of light blue and blue, which could indicate the presence of secondary metabolites and tannin. Compared to mimosa, as the commercial standard for tanning agents in the leather industry, Caesalpinia sappan L. presents promise as an eco-friendly substitute for basic chromium sulfate and a new alternative source of vegetable tannin for the leather industry.
26
Mwangi, Sharif Zuberi, Valerian Cosmas Silayo e Davis Naboth Chaula. "Optimization of Tannin’s Extraction from Cashew (Anacardium occidentale L.) Nut Testa for Use in Leather Tanning". Asian Journal of Applied Chemistry Research 15, n. 2 (26 aprile 2024): 7–16. http://dx.doi.org/10.9734/ajacr/2024/v15i2283.
Testo completoAbstract (sommario):
Extensive researches have been conducted over the years, focusing on the use of vegetable tannins to reduce pollution caused by mineral tanning. Vegetable tannins have been utilized commercially, but they remain costly and are not easily accessible. The purpose of this study was to optimize the tannin’s extraction from cashew (Anacardium occidentale L.) nut testa using water in order to determine their suitability in leather tanning. Samples of cashew nut testa were collected randomly from cashew nut processors in Mtwara region, Southern Tanzania. They were shade-dried and ground into powder. Various ratio of powder/water (1:6, 1:9, 1:12 and 1:15) -on weight basis were made for extraction, maintained at a temperature of 70 0C for 90 minutes. Results showed that, depending on the extract ratios, different tannin concentrations were obtained which had an implication on tannin extracted from powder. Experiment was found solution with ratio 1:9 have shown to extract about 50.73% of total tannins presented on cashew nut testa powder followed by solutions with ratio 1:12, ratio 1:15, and ratio 1:6 extracted about 46.27%, 43.51% and 38.95% respectively. Suitability of various tannins solution extracted from cashew nut testa was tested using conventional tanning process on sheepskins. The physical properties of the resultant leathers were determined using the standard methods (TBS/ISO). Under given condition, it has shown that using the ratios of 1:6, 1:9, 1:12 and 1:15 resulted in leather with tensile strength ranging between 19.41+6.36 MPa and 43.00+8.18 MPa and elongation at maximum load in the range of 34.48+10.12 % to 77.56+10.96 %., average shrinkage temperatures were above 75oC, and flexing test gave no damage of leather at 100,000 flexes. The physical properties of leather recorded have shown to meet the minimum recommended values from the standard (ISO 14931-2021). The mixing ratio 1:9 of cashew nut testa powder/water has been recommended for extracting tannin for vegetable tanning.
27
Mulyani, Elly, Herlina Herlina e Kurnia Suci. "Penetapan Kadar Tanin Ekstrak Daun Pagoda (Clerodendrum Paniculantum) Dengan Metode Spektrofotometri Visible Dan Titrasi Permanganometri". Lumbung Farmasi: Jurnal Ilmu Kefarmasian 3, n. 1 (9 gennaio 2022): 7. http://dx.doi.org/10.31764/lf.v3i1.7034.
Testo completoAbstract (sommario):
ABSTRAKIndonesia merupakan negara yang memiliki beraneka ragam tanaman obat yang salah satunya adalah tanaman pagoda (Clerodenrum paniculantum). Daun Pagoda (Clerodenrum paniculantum) mengandung senyawa flavanoid, terpenoid, tanin, alkaloid, sterol dan glikosida. Uji identifikasi tanin dari ekstrak daun pagoda penelitian (Hafiz dkk, 2016) dan (Fitriana, 2018) menjelaskan bahwa daun pagoda positif mengandung senyawa tanin yang belum diketahui kadarnya. Oleh karena itu, peneliti melakukan penetapan kadar tanin pada daun pagoda(Clerodenrum paniculantum). Daun pagoda yang telah dikeringkan di estraksi secara maserasi dengan mengunakan pelarut etanol 96% kemudian dilakukan uji kualitatif dan kuantitatif. Uji kualitatif menggunakan preaksi warna FeCl3 1% dan uji kuantitatif mengunakan dua metode yaitu Spektrofotometri Visibel dan titrasi permanganometri. Hasil dari kualitatif dengan menambahkan FeCl3 terjadi perubahan warna biru kehitaman menunjukan bahwa ekstrak daun pagoda pmengandung tanin. Hasil dari uji kuantitatif menggunakan spektrofotometri Visibel didapat kadar tanin yaitu 4,146% (15 ppm), 5,546% (20 ppm) dan 7,598% (30 ppm). Sedangakan menggunakan metode permanganometri didapatkan kadar rata-rata yaitu 0,443%. Kata kunci : Clerodendrum paniculantum; Tanin; Spektrofotometri Visibel; Permanganometri.ABSTRACTIndonesia is a country that has a variety of medicinal plants, one of which is the pagoda plant (Clerodenrum paniculantum). Pagoda leaves (Clerodenrum paniculantum) contain flavonoid compounds, terpenoids, tannins, alkaloids, sterols and glycosides. The tannin identification test from the research pagoda leaf extract (Hafiz et al, 2016) and (Fitriana, 2018) explained that the positive pagoda leaf contained an unknown level of tannin compounds. Therefore, the researchers determined the levels of tannins in pagoda (Clerodenrum paniculantum) leaves. The dried pagoda leaves were extracted by maceration using 96% ethanol solvent and then qualitative and quantitative tests were carried out. The qualitative test used 1% FeCl3 color reaction and the quantitative test used two methods, namely visible spectrophotometry and permanganometric titration. The results of the qualitative by adding FeCl3 there was a blue-black color change indicating that the pagoda leaf extract contains tannins. The results of the quantitative test using visible spectrophotometry obtained tannin levels of 4.146% (15 ppm), 5.546% (20 ppm) and 7.598% (30 ppm). While using the permanganometry method, the average level was 0.443%Keywords : Clerodendrum paniculantum; Tannins; Visible spectrophotometry; Permanganometric.
28
Ethiraj, Sumathi, e Janarthanam Balasundaram. "Phytochemical and Biological Activity of Cucurbita Seed Extract". JOURNAL OF ADVANCES IN BIOTECHNOLOGY 6, n. 1 (13 agosto 2016): 813–21. http://dx.doi.org/10.24297/jbt.v6i1.4821.
Testo completoAbstract (sommario):
The present study was performed to investigate the phytochemical screening, total phenol, tannin content, antioxidant and antibacterial activity from seed extracts of Cucurbita pepo and Cucurbita maxima (Tindivanam). The phytochemical analysis revealed the presence of active ingredients such as steroids, cardioglycosides, phenols, terpenoids, alkaloids and tannins in the seed extract of Cucurbita pepo followed by Cucurbita maxima. Gallic acid (GA), Tannic acid (TA) and Butylated Hydroxy Toluene (BHT) were taken as standard in case of total phenol, tannin and antioxidant activity respectively. Total phenol and tannin content were quantitatively estimated which recorded maximum in Cucurbita pepo (8.37±0.2 mg Gallic Acid Equivalents (GAE)/g and 20.47 ± 0.37 mg Tannic Acid Equivalents (TAE)/g). The seed extracts were evaluated for antioxidant activities by DPPH (1, 1– Diphenyl -2- picryl - hydrazyl) radical scavenging assay. Among the two species with different solvents used, maximum antioxidant activity was found in the acetone seed extract (84.27±0.19%) of Cucurbita pepo followed by Cucurbita maxima (67.83 ± 0.37%). Different concentrations of acetone seed extracts were tested for the anti-bacterial activity against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli using the agar disc diffusion technique. The acetone seed extracts of Cucurbita pepo had superior level of antimicrobial activity. The powerful antibacterial effect is attributed to the greater amount of tannins compound in the acetone seed extracts of Cucurbita pepo.
29
VAILLANCOURT, R., A. E. SLINKARD e R. D. REICHERT. "THE INHERITANCE OF CONDENSED TANNIN CONCENTRATION IN LENTIL". Canadian Journal of Plant Science 66, n. 2 (1 aprile 1986): 241–46. http://dx.doi.org/10.4141/cjps86-038.
Testo completoAbstract (sommario):
In lentil (Lens culinaris Medik.) condensed tannins are responsible for seed coat darkening during storage and the associated reduction in crop quality. The vanillin-HCl method was used to measure tannin concentration. Tannins were present only in the seed coat. Tannin concentration in the seed coat of 87 lines from the USDA World Lentil Collection ranged from 35 to 93 g kg−1 and averaged 63.3 g kg−1. The zero-tannin trait of PI 345635 lentil was controlled by a single recessive gene (tan tan) that had pleiotropic effects on plant pigmentation and seed coat thickness. Heritability of tannin concentration among lines containing tannin was 66.4 ± 4.4%, based on the components of variance method. Selection for lower or higher tannin concentration in lentil should be effective.Key words: Lentil, tannin, tannin genetics, proanthocyanidin, Lens culinaris
30
Degen, A. A., T. Mishorr, H. P. S. Makkar, M. Kam, R. W. Benjamin, K. Becker e H. J. Schwartz. "Effect of Acacia saligna with and without administration of polyethylene glycol on dietary intake in desert sheep". Animal Science 67, n. 3 (dicembre 1998): 491–98. http://dx.doi.org/10.1017/s1357729800032914.
Testo completoAbstract (sommario):
AbstractThe study was designed to measure (i) dry-matter intake (DMT) of sheep when diets including different tannins were offered and (ii) the effect of administration of polyethylene glycol (PEG), a tannin-binding agent, on DMI of tannin-rich diets. Acacia saligna phyllodes, a potential food for sheep, quebracho powder or tannic acid were added to a concentrate diet that served as a control and were offered to 16 ewe lambs (34·6 (s.d. 3·3) kg) that is, four lambs per diet. A. saligna has high levels of tannins; quebracho is a complex mixture of phenolic compounds in which condensed tannins predominate while tannic acid is a relatively pure example of a hydrolysable tannin. Intake was measured during four periods (I to IV) of 10 days each in which PEG was offered during periods II and IV. Food and water were available ad libitum. The DMI of the concentrate diet ranged between 925 glday and 1050 glday which was higher than for the other three diets (P < 0·05). The lambs consumed approximately 600 g dry matter (DM) of the diet that included 400 g A. saligna phyllodes per kg, and 500 g DM of the diets that included 100 glkg quebracho or 150 glkg tannic acid. With the quebracho and tannic acid diets, there was a distinct increase in intake when PEG was added and a decrease without PEG. This was not so with the Acacia diet when the intake remained high in period III without PEG and increased again in period IV with PEG. Body mass of control lambs increased in all periods and the increase was greater than in the other diets (P < 0·05). With the quebracho and tannic acid diets, there was an increase in body mass when PEG was added and a decrease without PEG. With the Acacia diet, there was a decrease in body mass in period I and an increase thereafter, even without PEG in period III.
31
Sasongko, Wahidin Teguh, Lies Mira Yusiati, Zaenal Bachruddin e Mugiono (Mugiono). "Optimalisasi Pengikatan Tanin Daun Nangka dengan Protein Bovine Serum Albumin (Optimalisation Binding of Jackfruit Leaves Tannin with Bovine Serum Albumin Protein)". Buletin Peternakan 34, n. 3 (21 febbraio 2012): 154. http://dx.doi.org/10.21059/buletinpeternak.v34i3.84.
Testo completoAbstract (sommario):
<p>Tannins are high molecular weight polyphenol compounds with ability to bind proteins. Based on the structure,<br />albumin are simple globular molecule protein. Optimalisation binding of jackfruit leave tannins to bovine serum (BSA)<br />albumin was done in two stages. The first stage was to determine levels of tannins and condensed tannins in jackfruit leaves grown in mediterranean soil types. Second research was optimalisation binding of jackfruit leaf tannins with<br />bovine serum albumin. In the second stage there was the determination of protein-percipitable phenolics compound and protein content using Lowry method. The data showed total phenol content was 10.63%, total tannin was 7.08%, and<br />condensed tannins 5.57%. The optimum capacity phenolic compound to bind protein of bovine serum albumin was 5.71+0.18 mg BSA/100 mg dry matter of jackfruit leaf, while 1 g tannin could bind 23.149 g BSA or 1 g condensed<br />tannin could bind 28.885 g BSA.</p><p><br />(Key words: Tannin, Total phenol, Total tannin, Condensed tannin, Bovine serum albumin)<br /><br /></p>
32
Bhushan, Bharat, M, R. Bhar, A. Kannan, Harisha M, Umesh B. U e Venkatesha M.M. "Effect of physical treatments on phenolics and tannins in Ficus roxburghii and Quercus leucotrichophora leaves". International Journal of Agricultural and Applied Sciences 4, n. 1 (30 giugno 2023): 28–32. http://dx.doi.org/10.52804/ijaas2023.415.
Testo completoAbstract (sommario):
Inadequate availability of straws and conventional concentrates is one of the major constraints for rearing large and small ruminants. Alternative or unconventional fodder resources play a supplementary role in meeting the demand of livestock owners; but these tree leaves contain some antinutritional factors. Tremal (Ficus roxburghii) and Oak (Quercus leucotrichophora) are among the traditional tree fodder sources available in the North Western Himalayan region. Their use a feed stuff for livestock is limited due to presence of tannis. So, the study was undertaken to assess the effect of different physical treatments on total phenol and tannin fractions of Tremal and Oak leaves. Fresh leaves lopped from Tremal and Oak trees of Kangra district of Himachal Pradesh were subjected to physical treatments like chopping and sun drying after chopping. The phenol and tannin fractions of these leaves were estimated before and after treatment. Total phenols, total tannin and hydrolysable tannin contents of the F. roxburghii and Q. leucotrichophora leaves were reduced significantly (P<0.0001) by both the physical treatments. However, both the treatments increased (P ≤ 0.0001) the condensed tannin content of F. roxburghii leaves, whereas chopping followed by sun drying also increased the non-tannin phenol contents. Both the treatments were effective in reducing tannin contents (both hydrolysable and condensed) of Q. leucotrichophora leaves. It may be concluded that physical treatments, chopping, chopping and sun drying, were though effective in reducing hydrolysable tannins, but were not effective in reducing condensed tannin contents of F. roxburghii leaves; whereas chopping, chopping and sun drying were effective in reducing tannin contents in case of Q. leucotrichophora leaves.
33
Costa, Antonio, Nazareth Fonseca, Sheyla Carvalho, Fernanda Santos, Luana Barki, Denise Freitas, Marcelo Herbst e Márcia Lutterbach. "Archaeometric investigations on naturally and thermally-aged iron-gall inks using different tannin sources". Open Chemistry 11, n. 11 (1 novembre 2013): 1729–39. http://dx.doi.org/10.2478/s11532-013-0303-7.
Testo completoAbstract (sommario):
AbstractThis paper investigates the behavior of paper strips containing iron-gall inks prepared with tannins from different sources, subjected to natural and thermally-induced aging. Results indicate that inks containing initial concentrations of ferrous sulphate ranging from 0.2 to 10.0 g are amenable to treatment with calcium phytate, and thata good correlation exists between the recovery of excess iron and the initial concentration. Infrared spectra showed an absorption band at 1,750 cm−1, typical of esther, solely in the samples prepared with a condensed tannin. The condensed nature of this tannin produced a different oxidation pattern, with iron removal inferior to those observed from inks produced with hydrolisable tannins. When tannic acid was used ferrous iron removals ranged from 0.050 to 1.800 g, decreasing to 0.5 g in the presence of copper; the same behavior was observed for the remaining hydrolisable tannins, with a lower recovery from the condensed tannin. The adopted natural aging procedure released a higher amount of ferrous iron compared to ASTM thermal aging. This was probably due to the marked effect of humidity, not considered in the thermal procedure. A series of archaeometric possibilities were used to help elucidate the degradation of cellulose strips impregnated with iron-gall inks.
34
McSweeney, Christopher S., Brian Palmer, Rowan Bunch e Denis O. Krause. "Isolation and Characterization of Proteolytic Ruminal Bacteria from Sheep and Goats Fed the Tannin-Containing Shrub Legume Calliandra calothyrsus". Applied and Environmental Microbiology 65, n. 7 (1 luglio 1999): 3075–83. http://dx.doi.org/10.1128/aem.65.7.3075-3083.1999.
Testo completoAbstract (sommario):
ABSTRACT Tannins in forages complex with protein and reduce the availability of nitrogen to ruminants. Ruminal bacteria that ferment protein or peptides in the presence of tannins may benefit digestion of these diets. Bacteria from the rumina of sheep and goats fed Calliandra calothyrsus (3.6% N and 6% condensed tannin) were isolated on proteinaceous agar medium overlaid with either condensed (calliandra tannin) or hydrolyzable (tannic acid) tannin. Fifteen genotypes were identified, based on 16S ribosomal DNA-restriction fragment length polymorphism analysis, and all were proteolytic and fermented peptides to ammonia. Ten of the isolates grew to high optical density (OD) on carbohydrates (glucose, cellobiose, xylose, xylan, starch, and maltose), while the other isolates did not utilize or had low growth on these substrates. In pure culture, representative isolates were unable to ferment protein that was present in calliandra or had been complexed with tannin. One isolate, Lp1284, had high protease activity (80 U), a high specific growth rate (0.28), and a high rate of ammonia production (734 nmol/min/ml/OD unit) on Casamino Acids and Trypticase Peptone. Phylogenetic analysis of the 16S ribosomal DNA sequence showed that Lp1284 was related (97.6%) to Clostridium botulinum NCTC 7273. Purified plant protein and casein also supported growth of Lp1284 and were fermented to ammonia. This is the first report of a proteolytic, ammonia-hyperproducing bacterium from the rumen. In conclusion, a diverse group of proteolytic and peptidolytic bacteria were present in the rumen, but the isolates could not digest protein that was complexed with condensed tannin.
35
Haroun, Mahdi. "COMPLEMENTARY ANALYTICAL TECHNIQUES PAPER, THIN-LAYER, HIDE-POWER, AND COMBINED METHODS FOR CHARACTERIZATIONOF TANNIN IN PLANTS". International Journal of Advanced Research 9, n. 10 (31 ottobre 2021): 777–85. http://dx.doi.org/10.21474/ijar01/13610.
Testo completoAbstract (sommario):
The polyphenolic compoundsextract rich in gallo-catechol tannins submitted to complementary analytical techniqueswas evaluated. The whole plantspecies screened were of the condensed type except Acacia seyal var. fistuala, Acaciaseyal var. seyal, Casuarina equistifolia, and Pithecellobium dulcewere of mixedhydrolysable-condensed(gallo-catechol) type. The quantitative data indicated that 5 parts (bark) out of 12 species, when extracted, contained more than 10% tannins (oven-dry basis), the level of commercial interest. The catechin numbers indicated that all the studied species contained condensed tannin in varying amounts (0.6-45.7), while the presence of both gallic acid and catechin means that the tannin is of mixed type. Thin-layer and paper chromatography with different solvent systems confirmed the presence of catechin and gallic acid, and showed that tannic acid, fisetin, epicatechin and some unidentified phenolics were present. However, dihydrofisetin and robinetin, which were used as standards, were not detected. Astringency values shows that the Acacia mellifera(0.18), Acacia seyalvar.fistuala(0.18), Pithecellobium dulce (0.15), Acacia senegal (0.14), Acacia farnesiana (0.13), Calotropis procera (0.13)barks could be used in place of A. mearnsii(international commercial tannin materials) (0.16) because the degree of relative astringency or the ability of their tannin to combine with protein is close to that of A. mearnsii in other words these six species can give leather with characteristics comparable with that of A. mearnsii.
36
Bueno, I. C. S., S. L. S. Cabral Filho, E. F. Nozella, M. R. S. R. Peçanha, A. P. Minho, D. M. S. S. Vitti, A. L. Abdalla e H. Louvandini. "Bioassay for measuring tannin effects based on gas production technique. 2. Dosage of polyethylene glycol". Proceedings of the British Society of Animal Science 2005 (2005): 216. http://dx.doi.org/10.1017/s1752756200011273.
Testo completoAbstract (sommario):
Tannins are secondary compounds that can bind protein and other nutrients and reduce their availability to the animals. Polyethylene glycol (PEG) has a great affinity with tannins and when it is added to the feed it is bound to tannins and releases the protein and other nutrients. There is no information about the amount of PEG that is needed to obtain the maximum precipitation of tannin and the minimum tannin effect. Some assays are conduced using doses of PEG according to the tannin content, but the activity of tannins can vary and this imply that the tannin analysis has to be done prior. The aim of this work was to evaluate doses of polyethylene glycol to minimize the effect of tannins on rumen fermentation.
37
Khairunnisa, Amalia, Fadlilaturrahmah Fadlilaturrahmah e Septiany Septiany. "Determination of SPF Value and Total Tannin in Ethyl Acetate Fraction of Peronema canescens Jack". Jurnal Pharmascience 10, n. 2 (23 ottobre 2023): 378. http://dx.doi.org/10.20527/jps.v10i2.16484.
Testo completoAbstract (sommario):
Daun Sungkai (Peronema canescens Jack) mengandung metabolit sekunder antara lain tannin, alkaloid, terpenoid, steroid, dan flavonoid. P. canescens merupakan tanaman asli Kalimantan Selatan yang berpotensi sebagai perawatan kulit alami berdasarkarkan kandungan tannin yang memiliki aktivitas antioksidan sehingga dapat dikembangkan sebagai produk tabir surya. Penelitian ini bertujuan untuk menentukan nilai SPF dan tannin total fraksi etil asetat daun Sungkai (P. canescens) menggunakan spektrofotometri UV-Vis. Metode ekstraksi dilakukan dengan maserasi menggunakan etanol 96% dan penggunaan fraksi n-heksana dan etil asetat. Penentuan tanin total menggunakan standar katekin dengan konsentrasi 40,60, 80, 100 dan 120 ppm. Hasil kadar tannin total sebesar 0,5586% ±0.01516 ekivalen katekin dan nilai SPF sebesar 5.703±0.021. Dengan demikian dapat disimpulkan daun Sungkai (Peronema canescens Jack) dapat dikembangkan sebagai tabir surya alami. Kata Kunci: Daun Sungkai, Tabir Surya, Tannin Total, UV-Vis, SPF Sungkai leaves (Peronema canescens Jack). contains secondary metabolites i.e tannins, alkaloids, terpenoids, steroids, and flavonoids. P. canescens, natural plant from South Kalimantan, has potential benefits as natural skincare based on tannin which contains antioxidant activity that can be developed as a sunscreen product. This study aimed to determine the sun protection factor (SPF) and total tannin ethyl acetate fraction of sungkai leaves (P. canescens) using UV-vis spectrophotometry. The extraction method was maceration with 96% ethanol and the fraction used n-hexane and ethyl acetate. The determination of total tannin with catechin standards concentration 40,60,80, 100 and 120 ppm. The result of total tannin was 0.5586% ±0.01516 catechin equivalents and the SPF value was 5.703±0.021. The conclusion of the research is that Peronema canescens Jack can be developed into natural sunscreen.
38
Adegbusi, Halid Sheriff, Ismail Amin, Norhaizan Mohd Esa e Zulfitri Azuan Mat Daud. "Application of Folin-Ciocalteau colorimetric method in the determination of total tannin in maize and soybean food products". International Food Research Journal 29, n. 5 (25 ottobre 2022): 1110–19. http://dx.doi.org/10.47836/ifrj.29.5.13.
Testo completoAbstract (sommario):
Yellow maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) are local raw materials used in the formulation of complementary foods in Nigeria. The presence of antinutritional factors such as tannins in them could disrupt the nutritional status in infants and young children, thus leading to malnutrition. However, data on the total tannin contents in maize, soybean, and their products remain limited. This could be due to the lack of a fast, accurate, and inexpensive analytical method for tannin determination. The present work thus evaluated the Folin-Ciocalteu (FC) assay for the accurate quantification of total tannin from yellow maize, soybean, and their products. Techniques including soaking, dehulling, oven-drying, boiling, and frying were used to process the raw materials, prior to grinding and subsequent formulation of their products. The FC method was validated to quantify the total tannin contents from extracts of tested samples by ultraviolet-visible (UV-Vis) spectrophotometry. The original extracts from the tested samples, and external standards from tannic acid and total phenolics (µg/µL) were used for method validation. The method validation showed that the instrumental response to standard tannic acid and the investigated analytes were specific, linear (R2 = 0.998), precise (% CV < 20%), and accurate (recovery = 91%). The limits of detection (LOD) and limits of quantification (LOQ) were 0.03 and 0.09 µg/µL, respectively. The validation complied with the requirements to ensure the reliability of the results. The combined processing techniques were also effective in reducing the total tannin content of maize (0.213 to 0.041% TAE) and soybean (0.257 to 0.064% TAE) by 81 and 75%, respectively. The present work demonstrated the suitability of the FC method as an analytical tool for the quantification of total tannin from plant-based food products.
39
Sallam, Ibrahim E., Amr Abdelwareth, Heba Attia, Ramy K. Aziz, Masun Nabhan Homsi, Martin von Bergen e Mohamed A. Farag. "Effect of Gut Microbiota Biotransformation on Dietary Tannins and Human Health Implications". Microorganisms 9, n. 5 (29 aprile 2021): 965. http://dx.doi.org/10.3390/microorganisms9050965.
Testo completoAbstract (sommario):
Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota–tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits.
40
Hagerman, Ann E., e Charles T. Robbins. "Specificity of tannin-binding salivary proteins relative to diet selection by mammals". Canadian Journal of Zoology 71, n. 3 (1 marzo 1993): 628–33. http://dx.doi.org/10.1139/z93-085.
Testo completoAbstract (sommario):
The tannin-binding specificity of salivary proteins in several mammals was investigated as a possible explanation for observed food habits. Moose (Alces alces) and beaver (Castor canadensis) produce salivary proteins that only bind the linear condensed tannins common in their preferred foods, such as willow, aspen, or birch. The mule deer (Odocoileus hemionus), which has a more generalized diet, produces salivary proteins that bind linear and branched-chain condensed tannins and gallotannins, but not an ellagitannin. The omnivorous black bear (Ursus americanus) produces salivary proteins that bind all types of tannins. In feeding trials beaver and mule deer were fed tannins that were not bound by salivary tannin-binding proteins in the in vitro assays. The results confirmed that these tannins reduce digestibility more than tannins that are bound by salivary proteins. Thus, salivary tannin-binding proteins are not always generalized scavengers of dietary tannins, but can be very specific for the types of tannins that are consumed in the preferred diet. The diversity of tannin chemistry and the specificity of salivary tannin-binding proteins must be considered in optimal foraging studies and in cost-benefit models of herbivore diet selection.
41
Datu, Fransiska N. S., Hasri Hasri e Diana Eka Pratiwi. "Identifikasi dan Uji Kestabilan Tanin dari Daging Biji Pangi (Pangium edule Reinw.) sebagai Bahan Pewarna Alami". Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia 22, n. 1 (27 settembre 2021): 29. http://dx.doi.org/10.35580/chemica.v22i1.21726.
Testo completoAbstract (sommario):
ABSTRAKPenelitian ini adalah penelitian eksplorasi untuk mengetahui jenis tanin, penetapan kadar tanin dan uji kestabilan tanin dari daging biji Pangi (Pangium edule Reinw.) dengan metode spektrofotometri menggunakan UV-VIS. Daging biji pangi diekstraksi dengan etanol 70%. Hasil uji kualitatif menggunakan pereaksi FeCl3 1%, Asam Asetat 10%, Pb Asetat 10%, HCl, Bromine, dan Tes Katekin, menunjukkan daging biji pangi termasuk jenis tanin terhidrolisis dengan kadar tanin rata-rata 15,54 % dan stabil pada suhu 80 – 100 ºC. Kata kunci : Pangium edule Reinw., Kadar Tanin, Spektrofotometri, UV-VIS ABSTRACTThis research for determining the kind of tannin and tannin assay and also the stability testing of tannin from meat seed of pangi has been done by using spectrophotometric method with UV-VIS. The meat seed of pangi fruit was extracted using 70% ethanol. The extract was tested using qualitative assay with reagent. Base on Qualitative test result with a reagent FeCl3 1%, Acetate Acid 10%, Pb Acetate 10%, HCl, bromine and catechin test,was obtained that meat seed of pangi contain hydrolyzed tannin. Tannin level was obtained on average 15.54 % and stable at a temperature of 80 – 1000C. Keywords: Pangium edule Reinw., Tannin assay, Spectrophotometric, UV-VIS
42
Watrelot, Aude A. "Tannin Content in Vitis Species Red Wines Quantified Using Three Analytical Methods". Molecules 26, n. 16 (14 agosto 2021): 4923. http://dx.doi.org/10.3390/molecules26164923.
Testo completoAbstract (sommario):
Tannin content in red wines is positively correlated with astringency perception and wine grade; however, tannin quantification is one of the main challenges. In this study, tannin content was quantified using three analytical methods in commercial red wines from Vitis vinifera and interspecific cold-hardy hybrids including Marquette, Frontenac, and Petite pearl cultivars. Protein (PP) and methylcellulose precipitation (MCP) methods were compared to a HPLC-DAD method, which is based on the interaction between tannins and a hydrophobic surface (RPC). Frontenac wines were the poorest in tannins and Cabernet sauvignon wines were the richest regardless of the method used. In cold-hardy red wines, the tannin content was higher in Marquette with high alcohol content, which suggested that the tannins were extracted from seeds rather than skins. The high limit of quantification of the PP method and the presence of anthocyanin di-glucosides in cold-hardy wines were parameters suggesting that protein and methylcellulose precipitation methods were neither suitable nor reliable for the quantification of tannins in cold-hardy red wines. The tannin content quantified by RPC was positively correlated to tannin quantified by MCP, suggesting that the RPC method would be relevant for the quantification of tannins in red wines.
43
Hong, Yan, Haokai Di, Shiwei Li, Kun Yang e Libo Zhang. "Mechanism of Extracting Germanium from Ge-Containing Solution with Tannins". Metals 13, n. 4 (15 aprile 2023): 774. http://dx.doi.org/10.3390/met13040774.
Testo completoAbstract (sommario):
The process of germanium–tannin complex is the oldest form of technology for extracting germanium from Ge-containing solutions. This reaction mechanism is relatively controversial as it imposes restrictions on ideas and methods for reducing the amount of tannin. In this paper, using SEM, TEM, FT-IR, XPS, NMR, TOF-SIMS and UV diffuse reflectance spectroscopy for a deep analysis of germanium–tannin complex, the mechanism of extracting germanium from Ge-containing solutions with tannins is investigated. The results show that the theoretical tannin complex mass is 30 times that of tannin mass, and the complex rate reaches 98.84%. The changes of -OH stretching band in FT-IR spectra, the emergence of C3H3GeO7, C2H3GeO6, and C8H7GeO7 in TOF-SIMS images, and the shift of Ge and O banding energy in XPS detail spectra provided definitive evidence for the germanium–tannin complex process, highlighting that the formed complexes of tannins with germanium involve six coordinate Ge-O bonds, which are obtained through orthophenol hydroxyl groups in tannins reacting with Ge4+. Furthermore, the complex mode of germanium–tannins is layer polymerization, which finally forms an agglomeration of complex flocs. The findings of this research is innovative, and can have a profound impact on the future introduction of various methods to reduce the mass of tannins.
44
BHATTA, R., O. ENISHI, Y. YABUMOTO, I. NONAKA, N. TAKUSARI, K. HIGUCHI, K. TAJIMA, A. TAKENAKA e M. KURIHARA. "Methane reduction and energy partitioning in goats fed two concentrations of tannin from Mimosa spp." Journal of Agricultural Science 151, n. 1 (12 aprile 2012): 119–28. http://dx.doi.org/10.1017/s0021859612000299.
Testo completoAbstract (sommario):
SUMMARYDietary manipulation is one promising approach to reducing methane (CH4) emissions from forage-fed ruminants. Studies were conducted to evaluate the effects of feeding two concentrations of tannins from Mimosa spp. on rumen fermentation, methanogenesis and energy partitioning in goats. Adult male goats were used in three trials where three diets with increasing concentrations of tannins (control, low-tannin and high-tannin) were fed in a switch-over design. The control diet consisted of 0·65 timothy hay, 0·20 crushed maize and 0·15 soybean meal; low- and high-tannin diets contained 0·975 and 0·950 of the control diet, respectively, mixed with 0·025 and 0·050 of a commercial compound containing tannins with mean crude protein (CP) of 147 g/kg dry matter (DM) and gross energy (GE) 19 MJ/kg DM, respectively. Total contents (DM basis) of tannins (hydrolysable and condensed) in the control, low- and high-tannin diets were 0, 2·8 and 5·6 g/kg DM, respectively. The tannin source contained 37 and 76 g/kg DM of condensed and hydrolysable tannins, respectively (DM basis). The DM (664 g/d) and GE intakes (19·0 MJ/d) were similar among diet groups. Digestibilities of all dietary components in the high-tannin diet were lower (P < 0·05) than low-tannin and control diets. The faecal energy (MJ/d) output was lowest in the control diet (3·49) and increased (P < 0·05) in tannin-fed goats (3·80; 4·87) resulting in a corresponding decrease in digestible energy (DE). Methane emission, expressed both on absolute and per unit of feed intake basis, decreased (P < 0·05) with increasing concentration of tannins in the diet. For example, CH4 energy excretion was 0·98, 0·87 and 0·76 MJ/d for goats on control, low- and high-tannin diets, respectively, whereas their corresponding values for CH4 conversion ratio were 0·079, 0·069 and 0·060 of GE intake. These results suggest that natural tannins, even at a low concentration (2·8 g/kg DM of the diet), reduce CH4 emissions, and tree leaves containing appreciable amounts of tannins may potentially be exploited as natural feed additives in ruminants.
45
Wahyuni, Idha Muthiah Dwi, Anis Muktiani e Marry Christiyanto. "Kecernaan Bahan Kering dan Bahan Organik dan Degradabilitas Serat pada Pakan yang Disuplementasi Tanin dan Saponin". Jurnal Agripet 14, n. 2 (1 ottobre 2014): 115–24. http://dx.doi.org/10.17969/agripet.v14i2.1886.
Testo completoAbstract (sommario):
(Dry matter and organic matter digestibility and fiber degradability in feed by tannin and saponin supplementation)ABSTRACT. The study was conducted to assess the effect of the addition of tannins, saponin and their combinations on the feed, as defaunation agent in the dry matter and organic matter digestibility and ADF, NDF degradability. The study used an experimental method with a completely randomized design. The treatments were T0 : feed without supplementation; T1: feed supplementation with 1,2% saponin; T2 : feed with supplemetation combined of 0,5% tannin and 0,9% saponin; T3 : feed with supplementation combined of 1,0% tannin and 0,6% saponin; T4 : feed with supplementation combined of 1,5% tannin and 0,3% saponin and T5 : feed with supplementation with 2% tannins. The result showed that DMD and OMD increased with treatment added combination of tannin and saponin. The best result for DMD and OMD in combination of 1,5% tannin and 0,3% saponin. Degradability of ADF and NDF was decreased on the supplemented feed. The addition of a combination of tannins and saponins in the feed at dose of 1% tannin and 0.6% saponin showed the best result that increased of DMD and OMD and give good value on NDF and ADF degradability.
46
Soenardjo, Nirwani, e Endang Supriyantini. "Analisis Kadar Tanin Dalam Buah Mangrove Avicennia marina Dengan Perebusan Dan Lama Perendaman Air Yang Berbeda". Jurnal Kelautan Tropis 20, n. 2 (22 novembre 2017): 90. http://dx.doi.org/10.14710/jkt.v20i2.1701.
Testo completoAbstract (sommario):
Mangrove fruit has the potential to be developed as a potential food source, but the presence of toxins in the fruit are considered harmful if consumed in the long run. Therefore, research needs to be done to eliminate or reduce the levels of toxins in the mangrove fruit, in order to increase the potential of the mangrove plants. The poison is in the mangrove fruit tannins. One alternative to reduce the levels of toxins in the fruit of the mangrove scrub with ash and water immersion.The purpose of this study was to determine the effect of treatment of ash powder content and the duration of water immersion on fruit tannin content of mangrove Avicennia.marina.The treatment was a long 24 hours of water immersion 4 times change of water (6 hours), 48 hours 8 times a change of water (6 hours), and 72 hours 12 times a change of water (6 hours). The results showed that treatment long soaking water to give a significant influence (P <0.05) toward decreased levels of mangrove Avicennia marina fruit tannins. Treatment a long 72 hours of water immersion 12 times a change of water (6 hours) to reduce levels of tannins by 28.80%. AbstrakBuah mangrove mempunyai potensi untuk dikembangkan menjadi sumber pangan yang potensial, akan tetapi dalam buahnya mengandung tannin . Tanin merupakan zat alami yang dihasilkan oleh buah mangrove yang memberi rasa getir. Oleh karena itu, perlu dilakukan penelitian untuk mengurangi kadar tannin dalam buah mangrove. Tujuan penelitian ini adalah untuk menganalisis pengaruh perlakuan lama waktu perendaman air terhadap kadar tanin buah mangrove A.marina.Perlakuan lama perendaman air 24 jam 4 kali pergantian air (6 jam), 48 jam 8 kali pergantian air (6 jam), dan 72 jam 12 kali pergantian air (6 jam). Hasil penelitian menunjukan bahwa perlakuan lama perendaman air memberikan pengaruh yang nyata (P < 0.05) terhadap penurunan kadar tanin buah mangrove Avicennia marina. Perlakuan lama perendaman air 72 jam 12 kali pergantian air (6 jam) menurunkan kadar tanin sebesar 28,80 %
47
Mahdi Haroun e Manal Mohammed Ahmed. "Appropriateness of Anogessus leiocarpus leaves and bark as vegetable tannins traditionally used in leather making in Sudan". GSC Advanced Research and Reviews 14, n. 1 (30 gennaio 2023): 007–13. http://dx.doi.org/10.30574/gscarr.2023.14.1.0371.
Testo completoAbstract (sommario):
Chrome tanning industry is dominated globally owing to its high versatility in quality leather production. However, Environmental impacts of chromium have shifted the interest of present study to chrome-free options. Vegetable tannins have been proven to be environmentally safe producing good quality leather with comparable properties as that of chrome tanned leather. As such, scarcity of vegetable tannin supply demands characterization of non-commercialized sources locally available to feed local tanners. A simple extraction technique was used with different temperature 35, 50, & 85 oC. Leaves and barks from Anogessus leiocarpus grown in Sudan can produce commercially acceptable tannins in terms of extract yield, tannin, total phenolic, flavonoid contents, and crosslinking ability comparable to the extract from A. mearnsii barks, which is a worldwide known to be commercial tannin source. Results shows that temperature influences on extraction yields and tannin content was low, except for extract from Anogessus leiocarpus leaves that has shown an increase pattern with raise in temperature. Total phenolic and flavonoid content varied insignificantly with increase in extraction temperature, except for total flavonoid content of extract from Anogessus leiocarpus leaves that observed to be high at 50 oC (30.7). Variations in extract properties between extracts from plant parts studied in this work were significant. Tensile strength values of tanned skin with leaves extracts are higher than that tanned with barks. On the other hand, tanned skin with leaves extract produced greater skin elongation 40.6±0.35 compared to barks extract.
48
Akhand, Pooja N., Veena Sharma e Anupam K. Pathak. "Comparative Studies of Phytochemicals Analysis and in vitro Antioxidant Properties of Various Solvent Extracts of Sphaeranthus indicus Collected from three Different Climatic Zones of Central India". Asian Journal of Chemistry 33, n. 9 (2021): 2237–43. http://dx.doi.org/10.14233/ajchem.2021.23413.
Testo completoAbstract (sommario):
In present study, the total phenolic, flavonoid, tannin contents and the antioxidant activity of various solvent extracts of Sphaeranthus indicus collected from three different regions of central India were assessed. Plants extracts were prepared using Soxhlation method, while the total phenols, flavonoids and tannins were measured by the spectrophotometric method. DPPH, metal chelating, nitric oxide, superoxide oxide scavenging activity and FRAP, reducing power, total antioxidant assays were also evaluated. The highest phenolic contents 268.22 GAE equivalent, flavonoids 441.33 QE equivalents and tannin content was 120.32 tannic acid equivalents (mg/g) obtained from ethanolic extracts of sample SIEE-1 compared to other two plants extract. Similarly, the highest flavonoid contents was observed in SIAE-1 aqueous extract and lowest in SIAE-2 and SIAE-3. Extract of SIEE-1 possessed maximum antioxidant potentiality and SIAE-2 shown the least antioxidant activity in all assays. It could be concluded that different agroclimatic conditions have effects on the total phenolics, flavonoids, tannin contents and antioxidant potentiality of S. indicus plant.
49
Kruthika, N. Lakshmi, G. Bhaskar Raju e S. Prabhakar. "Degradation of Tannic Acid Powered by TiO2 Nanoparticles". Materials Science Forum 734 (dicembre 2012): 117–26. http://dx.doi.org/10.4028/www.scientific.net/msf.734.117.
Testo completoAbstract (sommario):
The wastewater from the coir, pharmaceutical, leather, paper and pulp industries is contaminated with water-soluble poly phenolic compounds (tannins). Among various tannins, tannic acid is a typical hydrolysable tannin prevalent in wastewater. The degradation of tannic acid using TiO2 nanoparticles as photocatalyst was investigated. The effect of catalyst concentration, pH of aqueous suspension and also electron acceptors such as hydrogen peroxide (H2O2) and ozone (O3) on the degradation of tannic acid was studied. The degradation of tannic acid was found to be more efficient and complete in the presence of UV/TiO2/O3 compared to UV/TiO2/H2O2. The kinetics of degradation was observed to follow first order rate equation which indicates that the mineralization process is diffusion controlled.
50
., Priya, Krishan Kumar Selwal, Manjit Selwal, Harsha Nirvan e Garima Deswal. "Role of Tannase in Chronic Diseases: A review". Research Journal of Biotechnology 17, n. 1 (25 dicembre 2021): 198–208. http://dx.doi.org/10.25303/1701rjbt198208.
Testo completoAbstract (sommario):
Tannase is an inducible and extracellular microbial enzyme that hydrolyses the ester and depside linkages of tannic acid in hydrolysable tannins to release glucose, gallic acid, ellagic acid and propyl gallate. Tannase or tannin acyl hydrolase is an enzyme and has several applications in the field of science and technology. It is produced by different bacteria like lactobacillus, staphylococcus aureus, yeast and majorly by fungi. Due to its hydrolytic properties, tannase could be used to reduce the ill effects of tannins in beverages, food and tannery effluents for the production of gallic acid from tannin rich materials. Tannase is a natural anti-oxidant phenol found in numerous fruits and vegetables and various plant parts. The anti-proliferative and anti-oxidant properties of Tannase have prompted research into its potential health benefits. Despite tannase is considered as an important industrial enzymes,the present review describes its role in various chronic diseases.