Structure-activity relationship of condensed tannins and synergism with trans-cinnamaldehyde against Caenorhabditis elegans

DEFF Research Database (Denmark)

Ropiak, Honorata M; Desrues, Olivier; Williams, Andrew Richard

2016-01-01

Parasitic gastrointestinal nematodes (GIN) of livestock are increasingly developing resistance to synthetic nematocidal drugs. Moreover, the use of nematocides can induce ecotoxicity by affecting free-living nematodes. Condensed tannins (CT) are a structurally diverse group of bioactive plant com...

Linking the B ring hydroxylation pattern of condensed tannins to C, N and P mineralization. A case study using four tannins

NARCIS (Netherlands)

Nierop, K.G.J.; Preston, C.M.; Verstraten, J.M.

2006-01-01

Condensed tannins are a major component of litter inputs, but little is known about the effects of tannin structural variations on soil biological processes and organic matter development. Four different condensed tannins (CTs) extracted from balsam fir, western red cedar, kalmia and black spruce

Research observation: Hydrolyzable and condensed tannins in plants of the northwest

Science.gov (United States)

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, Edward E.

2003-01-01

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

Assessment of the anthelmintic activity of medicinal plant extracts and purified condensed tannins against free-living and parasitic stages of Oesophagostomum dentatum

DEFF Research Database (Denmark)

Williams, Andrew Richard; Ropiak, Honorata M.; Fryganas, Christos

2014-01-01

BackgroundPlant-derived condensed tannins (CT) show promise as a complementary option to treat gastrointestinal helminth infections, thus reducing reliance on synthetic anthelmintic drugs. Most studies on the anthelmintic effects of CT have been conducted on parasites of ruminant livestock. Oesop...

Evidence for functional heterogeneity both between and within four sources of condensed tannin

International Nuclear Information System (INIS)

Asquith, T.N.

1985-01-01

Condensed tannins are polymers of flavan-3-ols that are produced by many plants in a wide variety of tissues. The ability of these compounds to actively precipitate proteins has been linked to nutritional deficiencies in many animals. Four purified tannins (quebracho, wattle, pinto bean and sorghum) were compared to chemical assays and astringency towards [ 14 C]-BSA. Quebracho and wattle tannins were much less astringent and had longer chain lengths that sorghum or pinto bean tannins. Quebracho tannin had a very high affinity for salivary proline-rich glycoproteins (PRPs) and pinto bean tannin alone had a measurable affinity for soybean trypsin inhibitor. This suggests that tannin/protein interactions in vivo may be very specific. Protein bound carbohydrate enhanced the binding of PRPs to tanning and conferred specificity on the interactions. Carbohydrate also increases the solubility of protein/tanning complexes, which may aid the animal in eliminating the complexes. [ 125 I]-labeled condensed tannin was shown to retain the ability to discriminate between high and low affinity proteins. [ 125 I]-labeled phenols were isolated from livers and kidneys of rats fed [ 125 I]-labeled tannin. The techniques described in this thesis should be widely applicable to studying in vivo functions of condensed tannins

Condensed Tannins from Longan Bark as Inhibitor of Tyrosinase: Structure, Activity, and Mechanism.

Science.gov (United States)

Chai, Wei-Ming; Huang, Qian; Lin, Mei-Zhen; Ou-Yang, Chong; Huang, Wen-Yang; Wang, Ying-Xia; Xu, Kai-Li; Feng, Hui-Ling

2018-01-31

In this study, the content, structure, antityrosinase activity, and mechanism of longan bark condensed tannins were evaluated. The findings obtained from mass spectrometry demonstrated that longan bark condensed tannins were mixtures of procyanidins, propelargonidins, prodelphinidins, and their acyl derivatives (galloyl and p-hydroxybenzoate). The enzyme analysis indicated that these mixtures were efficient, reversible, and mixed (competitive is dominant) inhibitor of tyrosinase. What's more, the mixtures showed good inhibitions on proliferation, intracellular enzyme activity and melanogenesis of mouse melanoma cells (B 16 ). From molecular docking, the results showed the interactions between inhibitors and tyrosinase were driven by hydrogen bond, electrostatic, and hydrophobic interactions. In addition, high levels of total phenolic and extractable condensed tannins suggested that longan bark might be a good source of tyrosinase inhibitor. This study would offer theoretical basis for the development of longan bark condensed tannins as novel food preservatives and medicines of skin diseases.

Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests

Science.gov (United States)

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, E.E.

2003-01-01

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

Condensed tannins: Quinone methide intermediates in procyanidin synthesis

Science.gov (United States)

Richard W. Hemingway; L. Y. Foo

1983-01-01

Proanthocyanidins (condensed tanruns) are widely distributed in plants and are found in sufficiently high concentration in some tree barks to encourage their industrial utilization. These polymers consist of flavanoid units linked through the C-4 of the pyran ring to the C-6 or C-8 carbons of the aromatic A-ring. Recent advances in the chemistry of condensed tannins...

Tannins gravimetric yield condensed in Anadenanthera peregrina bark in different diameter classes

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Caroline Junqueira Sartori

2014-06-01

Full Text Available This work aimed to determine the gravimetric yield of condensed tannins in the Anadenanthera peregrina bark in different diameter classes. Fifty-nine trees samples were collected of Anadenanthera peregrina, at 1.30m of the ground (diameter at breast height - DBH, distributed in seven diameter classes. The barks were dried and crushed in mill of hammer. Composite sample was made to prepare the extract. The extraction was done using water in the ratio 15:1 (v/w, added 3% sodium sulfite (w/w in water-bath at 70°C for 4 hours. The material was filtered using fine cloth strainer and concentrated on a heating plate at approximately 150 g. It was determined the extract mass and removed 10 g for obtaining solids content and 20g for the Stiasny's index. The average values of total solids content, Stiasny's index, condensed tannin content and the compound content non-tannin were 11.34%; 75.79%; 12.76% and 4.07%, respectively. The content of solids, Stiasny's index, compound content non-tannin show significant differences between diameter classes. For the condensed tannins production, the diameter class parameter there was no influence.

Inhibition of α-Amylases by Condensed and Hydrolysable Tannins: Focus on Kinetics and Hypoglycemic Actions

Directory of Open Access Journals (Sweden)

Camila Gabriel Kato

2017-01-01

Full Text Available The aim of the present study was to compare the in vitro inhibitory effects on the salivary and pancreatic α-amylases and the in vivo hypoglycemic actions of the hydrolysable tannin from Chinese natural gall and the condensed tannin from Acacia mearnsii. The human salivary α-amylase was more strongly inhibited by the hydrolysable than by the condensed tannin, with the concentrations for 50% inhibition (IC50 being 47.0 and 285.4 μM, respectively. The inhibitory capacities of both tannins on the pancreatic α-amylase were also different, with IC50 values being 141.1 μM for the hydrolysable tannin and 248.1 μM for the condensed tannin. The kinetics of the inhibition presented complex patterns in that for both inhibitors more than one molecule can bind simultaneously to either the free enzyme of the substrate-complexed enzyme (parabolic mixed inhibition. Both tannins were able to inhibit the intestinal starch absorption. Inhibition by the hydrolysable tannin was concentration-dependent, with 53% inhibition at the dose of 58.8 μmol/kg and 88% inhibition at the dose of 294 μmol/kg. For the condensed tannin, inhibition was not substantially different for doses between 124.4 μmol/kg (49% and 620 μmol/kg (57%. It can be concluded that both tannins, but especially the hydrolysable one, could be useful in controlling the postprandial glycemic levels in diabetes.

Impact of chemical structure of flavanol monomers and condensed tannins on in vitro anthelmintic activity against bovine nematodes.

Science.gov (United States)

Desrues, Olivier; Fryganas, Christos; Ropiak, Honorata M; Mueller-Harvey, Irene; Enemark, Heidi L; Thamsborg, Stig M

2016-04-01

Plants containing condensed tannins (CT) may have potential to control gastrointestinal nematodes (GIN) of cattle. The aim was to investigate the anthelmintic activities of four flavan-3-ols, two galloyl derivatives and 14 purified CT fractions, and to define which structural features of CT determine the anti-parasitic effects against the main cattle nematodes. We used in vitro tests targeting L1 larvae (feeding inhibition assay) and adults (motility assay) of Ostertagia ostertagi and Cooperia oncophora. In the larval feeding inhibition assay, O. ostertagi L1 were significantly more susceptible to all CT fractions than C. oncophora L1. The mean degree of polymerization of CT (i.e. average size) was the most important structural parameter: large CT reduced larval feeding more than small CT. The flavan-3-ols of prodelphinidin (PD)-type tannins had a stronger negative influence on parasite activity than the stereochemistry, i.e. cis- vs trans-configurations, or the presence of a gallate group. In contrast, for C. oncophora high reductions in the motility of larvae and adult worms were strongly related with a higher percentage of PDs within the CT fractions while there was no effect of size. Overall, the size and the percentage of PDs within CT seemed to be the most important parameters that influence anti-parasitic activity.

Effect of condensed tannins addition on the astringency of red wines.

Science.gov (United States)

Soares, Susana; Sousa, André; Mateus, Nuno; de Freitas, Victor

2012-02-01

Astringency has been defined as a group of sensations involving dryness, tightening, and shrinking of the oral surface. It has been accepted that astringency is due to the tannin-induced interaction and/or precipitation of the salivary proline-rich proteins (PRPs) in the oral cavity, as a result of the ingestion of food products rich in tannins, for example, red wine. The sensory evaluation of astringency is difficult, and the existence of fast and reliable methods to its study in vitro is scarce. So, in this work, the astringency of red wine supplemented with oligomeric procyanidins (condensed tannins), and the salivary proteins (SP) involved in its development were evaluated by high-performance liquid chromatography analysis of human saliva after its interaction with red wine and by sensorial evaluation. The results show that for low concentration of tannins, the decrease of acidic PRPs and statherin is correlated with astringency intensity, with these families having a high relative complexation and precipitation toward condensed tannins comparatively to the other SP. However, for higher concentrations of tannins, the relative astringency between wines seems to correlate's to the glycosylated PRPs changes. This work shows for the first time that the several families of SP could be involved in different stages of the astringency development.

Nutritional composition and condensed tannin concentration changes as browse leaves become litter.

Science.gov (United States)

Acero, Amanda; Muir, James P; Wolfe, Richard M

2010-12-01

The role of condensed tannins (CT) in ruminant nutrition and health makes changes in leaf litter (LL) after abscission of interest. This study compared the effect of different drying methods of green leaves (GL) with that of natural drying of LL on CT, fibre, crude protein (CP) and phosphorus (P) concentrations in nine Texas browse species. Leaves harvested before autumn shedding were oven-dried (OD) or freeze-dried (FD). Where different (P Drying method changed total CT concentration in three species. Where different, fibre fraction concentrations were greater in LL than in GL, regardless of drying method. In some species, CP and P concentrations were lower in LL than in GL, but in five species they did not change (P > 0.05) from GL to LL, with CP concentrations ranging from 63 to 151 g kg(-1) in the latter. Browse LL had high nutritive value and CT concentrations, explaining why browsing ruminants utilise this feed resource. However, changes in nutrient and CT concentrations as leaves become litter in some species mean that information on one is not necessarily applicable to the other. Copyright © 2010 Society of Chemical Industry.

Condensed tannin in Eragrostis chloromelas leaves deters feeding ...

African Journals Online (AJOL)

We investigated the feeding responses of a generalist grasshopper, the brown locust(Locusta pardalina), to leaves of the grass Eragrostis chloromelas differing in polyphenol content. For three specimens of E. chloromelas, the presence of condensed tannin in epidermal cells was confirmed by histochemical staining, while ...

饲草中缩合单宁的研究进展%Progress in Condensed Tannins of Forage

Institute of Scientific and Technical Information of China (English)

朱琳; 陈鑫珠; 张建国

2012-01-01

Feeding a high concentration of condensed tannins will reduce protein degradation and voluntary feed intake, damage abomasum or intestine. However, appropriate concentration of condensed tannins have beneficial effects on prevention of bloat and pulmonary edema, reducing parasitic disease and pastoral flavour in meat products, improving animal performance. Condensed tannins are clearly a "double edged sword" for feeding value. Successful management of condensed tannins depends on a combination of chemical analysis and animal experimentation. This paper is a review on nutrition and anti-nutrition of condensed tannins for ruminants, the factors affecting content of condensed tannins in forage, and the methods of controling concentration of condensed tannins. Research on successful management of condensed tannins will offer a real benefit for farmers.%饲料中高浓度的缩合单宁会降低动物对营养物质的消化利用率,影响自愿采食量,甚至损伤肠胃.适宜含量的缩合单宁,又能阻止臌胀病、肺水肿的发生,降低寄生虫病害的影响,改善肉质品味,提高动物的生产性能.论文概述了缩合单宁的营养作用、抗营养作用,影响饲草缩合单宁含量的因素,以及控制缩合单宁含量的方法,以便在实践中合理应用缩合单宁.

Protein Binding Capacity of Different Forages Tannin

Science.gov (United States)

Yusiati, L. M.; Kurniawati, A.; Hanim, C.; Anas, M. A.

2018-02-01

Eight forages of tannin sources(Leucaena leucocephala, Arachis hypogaea, Mimosa pudica, Morus alba L, Swietenia mahagoni, Manihot esculenta, Gliricidia sepium, and Bauhinia purpurea)were evaluated their tannin content and protein binding capacity. The protein binding capacity of tannin were determined using precipitation of bovine serum albumin (BSA). Swietenia mahagonihas higest total tannin level and condensed tannin (CT) compared with other forages (P<0.01). The Leucaena leucocephala has highest hydrolysable tannin (HT) level (P<0.01). The total and condensed tannin content of Swietenia mahagoni were 11.928±0.04 mg/100 mg and 9.241±0.02mg/100mg dry matter (DM) of leaves. The hydrolysable tannin content of Leucaena leucocephala was 5.338±0.03 mg/100 mg DM of leaves. Binding capacity was highest in Swietenia mahagoni and Leucaena leucocephala compared to the other forages (P<0.01). The optimum binding of BSA to tannin in Leucaena leucocephala and Swietenia mahagoniwere1.181±0.44 and 1.217±0.60mg/mg dry matter of leaves. The present study reports that Swietenia mahagoni has highest of tannin content and Leucaena leucocephala and Swietenia mahagoni capacity of protein binding.

Effect of Condensed Tannins on Bacterial Diversity and Metabolic Activity in the Rat Gastrointestinal Tract

Science.gov (United States)

Smith, Alexandra H.; Mackie, Roderick I.

2004-01-01

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 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. PMID:14766594

variability in condensed tannins and bitterness in spider plant ...

African Journals Online (AJOL)

ACSS

Spider plant (Cleome gynandra L.) contributes considerably to the nutrition and medicines of communities in southern Africa. However, its utilisation is limited by its bitterness caused by condensed tannins. Unfortunately, processing options that reduce the bitterness also remove nutritionally and medicinally useful ...

Isolation of condensed tannins in individual size from grape seeds and their impact on astringency perception

OpenAIRE

Ma, Wen; Waffo-Téguo, Pierre; Jourdes, Michael; Li, Hua; Teissedre, Pierre Louis

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. The influence of DP size of condensed tannins on astringency perception remains unclear for decades. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the no...

Influence of wine pectic polysaccharides on the interactions between condensed tannins and salivary proteins.

Science.gov (United States)

Carvalho, Elisabete; Mateus, Nuno; Plet, Benoit; Pianet, Isabelle; Dufourc, Erick; De Freitas, Victor

2006-11-15

Alpha-amylase, a major human salivary protein, and IB8c, a representative of the proline-rich proteins, were obtained by isolation from saliva and by solid-phase synthesis, respectively. The interactions between these proteins and condensed tannins isolated from grape seeds were studied at different protein and tannin concentrations by measuring their aggregation. Pectic polysaccharides were isolated from wine, and their effect on protein tannin aggregation was assessed. The results presented in this study showed that the most acidic fractions of arabinogalactan proteins have the ability to inhibit the formation of aggregates between the grape seed tannins and the two different salivary proteins. Rhamnogalacturonan II has the same ability toward alpha-amylase but not IB8c under the conditions of the present study. Polysaccharides show effects at concentrations at which they are present in wine, which could mean an influence in wine astringency. The interaction between condensed tannins and alpha-amylase is differently affected by ionic strength when compared with IB8c.

Condensed tannins in some forage legumes: their role in the prevention of ruminant pasture bloat.

Science.gov (United States)

Lees, G L

1992-01-01

For the past 20 years, the focus in our laboratory has been on finding the causes of ruminant pasture bloat and eventually breeding a bloat-safe alfalfa (Medicago sativa L.); i.e., with bloat potential reduced to the economic threshold. In the mid-seventies, the mechanisms of bloat were explored and found to be more physical than chemical. Characteristic of all bloating legumes after ingestion was a very rapid initial rate of ingestion by rumen microbes. Through the study of bloating and non-bloating legumes, factors were elucidated in the plant that would slow this process. One of these factors was the presence of condensed tannins in the herbage. Some of the non-bloating legumes contained these secondary metabolites, but no condensed tannins were found in any of the bloating legumes. Therefore, species containing an appreciable amount of condensed tannins in their leaves and stems are considered to be non-bloating. Conventional breeding methods have not been successful in producing an alfalfa with condensed tannins in its herbage. New approaches using tissue culture techniques are being attempted, but genetic engineering has the greatest potential for success.

Synergistic inhibition of Haemonchus contortus exsheathment by flavonoid monomers and condensed tannins

DEFF Research Database (Denmark)

Klongsiriwet, Chaweewan; Quijada, Jessica; Williams, Andrew Richard

2015-01-01

This study investigated the separate and combined anthelmintic (AH) effects of different phenolic compounds, including condensed tannins and flavonoids, all of which are known to occur in willow leaves, a potentially valuable dry season feed. A range of contrasting model tannins, which span the w...

MALDI-TOF MS analysis of condensed tannins with potent antioxidant activity from the leaf, stem bark and root bark of Acacia confusa.

Science.gov (United States)

Wei, Shu-Dong; Zhou, Hai-Chao; Lin, Yi-Ming; Liao, Meng-Meng; Chai, Wei-Ming

2010-06-15

The structures of the condensed tannins from leaf, stem bark and root bark of Acacia confusa were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and their antioxidant activities were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. The results showed that the condensed tannins from stem bark and root bark include propelargonidin and procyanidin, and the leaf condensed tannins include propelargonidin, procyanidin and prodelphinidin, all with the procyanidin dominating. The condensed tannins had different polymer chain lengths, varying from trimers to undecamers for leaf and root bark and to dodecamers for stem bark. The condensed tannins extracted from the leaf, stem bark and root bark all showed a very good DPPH radical scavenging activity and ferric reducing power.

Characterization and Antioxidant Properties of the Condensed Tannins from Alaska Cedar Inner Bark

Directory of Open Access Journals (Sweden)

Martha Rosales-Castro

2014-05-01

Full Text Available The structure and antioxidant activity of condensed tannins isolated from Alaska Cedar inner bark have been investigated. Oligomers of flavan-3-ol were purified by column chromatography (Sephadex LH-20 and analyzed by 13CNMR and MALDI-TOF MS spectrometries. Their antioxidant activities were measured using 1,1’-diphenyl-2-picrylhydrazyl (DPPH, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS free radicals scavenging, ferric reducing/antioxidant power (FRAP, and β-carotene-linoleic acid model system (β-CLAMS assays. Results showed that the condensed tannins consents of both homogeneous and heterogeneous oligomers of procyanidins (catechin/epicatechin and prodelphinidins (gallocatechin/ epigallocatechin flavan-3-ol units; and oligomers from trimmers to heptamers with dominant interflavan linkages B-type as it is most common in proanthocyanidins. Condensed tannins showed significant ntioxidant activity as the median inhibition capacity IC 50 is comparable to the catechin control response. Alaska Cedar inner bark oligomers show high antioxidant capacity, evaluated by both methods based on electron transfer mechanisms and hydrogen atom transfer reactions. This bark may be considered as a new source of natural antioxidants for nutraceutical ingredients.

Factors affecting ANKOM™ fiber analysis of forage and browse varying in condensed tannin concentration.

Science.gov (United States)

Terrill, Thomas H; Wolfe, Richard M; Muir, James P

2010-12-01

Browse species containing condensed tannins (CTs) are an important source of nutrition for grazing/browsing livestock and wildlife in many parts of the world, but information on fiber concentration and CT-fiber interactions for these plants is lacking. Ten forage or browse species with a range of CT concentrations were oven dried and freeze dried and then analyzed for ash-corrected neutral detergent fiber (NDFom) and corrected acid detergent fiber (ADFom) using separate samples (ADFSEP) and sequential NDF-ADF analysis (ADFSEQ) with the ANKOM™ fiber analysis system. The ADFSEP and ADFSEQ residues were then analyzed for nitrogen (N) concentration. Oven drying increased (P < 0.05) fiber concentrations with some species, but not with others. For high-CT forage and browse species, ADFSEP concentrations were greater (P < 0.05) than NDFom values and approximately double the ADFSEQ values. Nitrogen concentration was greater (P < 0.05) in ADFSEP than ADFSEQ residues, likely due to precipitation with CTs. Sequential NDF-ADF analysis gave more realistic values and appeared to remove most of the fiber residue contaminants in CT forage samples. Freeze drying samples with sequential NDF-ADF analysis is recommended in the ANKOM™ fiber analysis system with CT-containing forage and browse species. Copyright © 2010 Society of Chemical Industry.

Fast atom bombardment mass spectrometry of condensed tannin sulfonate derivatives

Science.gov (United States)

J.J. Karchesy; L.Y. Foo; Richard W. Hemingway; E. Barofsky; D.F. Barofsky

1989-01-01

Condensed tannin sulfonate derivatives were studied by fast atom bombardment mass spectrometry (FAB-MS) to assess the feasibility of using this technique for determining molecular weight and structural information about these compounds. Both positive- and negative-ion spectra provided useful data with regard to molecular weight, cation species present, and presence of...

The implications of condensed tannins on the nutritive value of temperate forages fed to ruminants.

Science.gov (United States)

Barry, T N; McNabb, W C

1999-04-01

New methodology for measuring forage condensed tannin (CT) content is described and the effects of CT upon forage feeding and nutritive value for ruminant animals are reviewed. CT react with forage proteins in a pH-reversible manner, with reactivity determined by the concentration, structure and molecular mass of the CT. Increasing concentrations of CT in Lotus corniculatus and Lotus pedunculatus reduce the rates of solubilization and degradation of fraction 1 leaf protein in the rumen and increase duodenal non-NH3 N flow. Action of medium concentrations of total CT in Lotus corniculatus (30-40 g/kg DM) increased the absorption of essential amino acids from the small intestine and increased wool growth, milk secretion and reproductive rate in grazing sheep without affecting voluntary feed intake, thus improving the efficiency of food conversion. High concentrations of CT in Lotus pedunculatus (75-100 g/kg DM) depressed voluntary feed intake and rumen carbohydrate digestion and depressed rates of body and wool growth in grazing sheep. The minimum concentration of CT to prevent rumen frothy bloat in cattle is defined as 5 g/kg DM and sheep grazing CT-containing legumes were shown to better tolerate internal parasite infections than sheep grazing non CT-containing forages. It was concluded that defined concentrations of forage CT can be used to increase the efficiencies of protein digestion and animal productivity in forage-fed ruminants and to develop more ecologically sustainable systems of controlling some diseases under grazing.

Antioxidant and antidiabetic properties of condensed tannins in acetonic extract of selected raw and processed indigenous food ingredients from Kenya.

Science.gov (United States)

Kunyanga, Catherine Nkirote; Imungi, Jasper Kathenya; Okoth, Michael; Momanyi, Clare; Biesalski, Han Konrad; Vadivel, Vellingiri

2011-05-01

Recently, tannins have received considerable attention as health-promoting component in various plant foods and several studies have reported on its nutraceutical properties. However, no study has established the role of condensed tannins in indigenous foods of Kenya. Therefore, this study was designed to evaluate the antioxidant activity (DPPH and FRAP) and antidiabetic effects (α-amylase and α-glucosidase inhibition activities) of condensed tannins in some selected raw and traditionally processed indigenous cereals, legumes, oil seeds, and vegetables. The condensed tannin content of the grains and vegetables ranged between 2.55 and 4.35 g/100 g DM and 1.53 and 5.73 g/100 g DM, respectively. The scavenging effect of acetonic extract on DPPH radical ranged from 77% to 90% while the reducing power was found to be 31 to 574 mmol Fe(II)/g DM in all the investigated food ingredients. The condensed tannin extracts of the analyzed samples showed promising antidiabetic effects with potential α-amylase and α-glucosidase inhibition activities of 23% to 44% and 58% to 88%, respectively. Condensed tannins extracted from the amaranth grain, finger millet, field bean, sunflower seeds, drumstick, and amaranth leaves exerted significantly higher antioxidant and antidiabetic activities than other food ingredients. Among the traditional processing methods, roasting of grains and cooking of vegetables were found to be more suitable mild treatments for preserving the tannin compound and its functional properties as opposed to soaking + cooking and blanching treatments. The identified elite sources of optimally processed indigenous food ingredients with promising results could be used as health-promoting ingredients through formulation of therapeutic diets. © 2011 Institute of Food Technologists®

Evaluating effects of tannins on extent and rate of in vitro gas and CH4, production using an automated pressure evaluation system (APES)

NARCIS (Netherlands)

Pellikaan, W.F.; Stringano, E.; Leenaars, J.; Bongers, L.J.G.M.; Laar-van Schuppen, van S.; Plant, J.; Mueller-Harvey, I.

2011-01-01

An in vitro study was conducted to investigate effects of tannins on extent and rate of gas and CH4 production using an automated pressure evaluation system (APES). In this study three condensed tannins (CT; quebracho, grape seed, green tea tannins) and four hydrolysable tannins (HT; tara, valonea,

Extraction and evaluation of condensed tannins from bark of eleven species of trees from Costa Rica

International Nuclear Information System (INIS)

Aguilar Lopez, Jorge; Vega Guzman, Ileana; Borbon Alpizar, Henry; Soto Fallas, Roy Mario; Jaen Jimenez, Jean Carlo; Vargas Abarca, Ana Sofia; Jimenez Bonilla, Pablo; Herrera Nunez, Jacqueline

2012-01-01

A study is made regarding the nature and the amount of condensed tannin which can extract of bark from 11 tree species present in Costa Rica: guanacaste (Enterolobium cyclocarpum), cork oak (Licania arborea), jobo (Spondias mombin), pochote (Pachira quinata), loquat (Manilkara chicle), almond (Andira inermis), oak (Tabebuia rosea), cedar (Cedrela odorata), cenizaro (Samanea saman), pine (Pinus caribaea) and cypress (Cupressus lusitanica). The cortex samples were prepared, dried and extracted with ethanol. The ethanolic extracts were analyzed for condensed tannin content through the number of Stiasny, and characterized by infrared spectroscopy (FT-IR). The species with the highest proportion of extracted material were: guanacaste (9.5841% w/w), pochote (15.0066% w/w), pine (19.3400% w/w) and cypress (10.5300% w/w). The extracts with a higher proportion of condensed tannins have been: cork oak (61.9% w/w), jobo (66.1% w/w), pochote (72.8% w/w), loquat (50.5% w/w), cedar (72.7% w/w) and pine (70.7% w/w). (author) [es

Nitrogen levels and yeast viability during ethanol fermentation of grain sorghum containing condensed tannins

Energy Technology Data Exchange (ETDEWEB)

Mullins, J T; NeSmith, C

1988-01-01

Selected varieties of sorghum, Sorghum bicolor (L.) Moench, give high crop yields and they also return to favorable energy balance in terms of energy calories produced per cultural energy invested. The brown, condensed-tannin, bird- and mold-resistant varieties illustrate these advantages, but their nutritional value and ability to support the expected rate of ethanol fermentation is significantly lower than that of non-brown sorghums. It has been previously shown that the addition of nitrogen to brown sorghum mash supports a high rate of fermentative metabolism without removing the tannins, and suggested that the basis for the inhibition of ethanol fermentation was nitrogen starvation of the yeast cells. In this investigation, it is demonstrated that the addition of protease enzyme to mash results in an increase in amino nitrogen sufficient to support accelerated rates of ethanol fermentation by yeast cells. Thus, the hypothesis commonly cited in the literature that the presumed inhibitor, condensed tannins, function to reduce fermentative metabolism solely via the binding and precipitation of proteins is rejected.

In vitro effects of extracts and purified tannins of sainfoin (Onobrychis viciifolia) against two cattle nematodes

DEFF Research Database (Denmark)

Novobilský, A.; Stringano, E.; Hayot Carbonero, C.

2013-01-01

Abstract Sainfoin (Onobrychis viciifolia) is a condensed tannin (CT)-containing legume and has anthelmintic potential against gastrointestinal nematodes of ruminants. This study investigated in vitro effects of acetone/water extracts and derived CT fractions from different types of sainfoin (i...

Isolation of condensed tannins in individual size from grape seeds and their impact on astringency perception

Directory of Open Access Journals (Sweden)

Ma Wen

2016-01-01

Full Text Available Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. The influence of DP size of condensed tannins on astringency perception remains unclear for decades. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5 was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed.

In vivo assessment of the ability of condensed tannins to interfere with the digestibility of plant protein in sheep

Energy Technology Data Exchange (ETDEWEB)

Andrabi, S.M.; Ritchie, M.M.; Stimson, C.; Horadagoda, A.; Hyde, M.; McNeill, D.M. [MC Franklin Laboratory, Faculty of Veterinary Science, University of Sydney, Camden, NSW (Australia)]. E-mail: karalue@bigpond.net.au

2005-08-19

To assess the effect of condensed tannin (CT) astringency on the digestibility of protein post-ruminally, CT were purified from four types (accessions) of Mulga (Acacia aneura), and a Leucaena pallida and dosed into sheep as complexes with {sup 15}N-plant protein (tannin-protein complexes, TPC), together with an indigestible marker, chromium-EDTA (Cr-EDTA). Each CT treatment dose comprised 12 mg CT, 10 mg {sup 15}N-protein, and 2.77 mg of Cr. A protein-only control (same as the other TPC solutions but without any CT) treatment was also included to make a total of six treatments. Treatments were applied in two 6 x 6 Latin Square designs with 72 h between each infusion for each sheep. In the first, the solutions were infused post-ruminally via an abomasal cannula. In the second they were dosed directly into the mouth following an intra-nasal dose of an analogue of vasopressin in an attempt to stimulate the oesophageal groove reflex to direct the solutions more efficiently toward the small intestine. Results showed no detectable effect of CT type on the in vivo digestibility of the {sup 15}N-protein. Protein digestibilities were uniformly high, indicative of complete dissociation of the TPC. There was no correlation between protein digestibility, mouth to faeces, and protein digestibility, abomasum to faeces (P > 0.05). In vivo digestibility was also uncorrelated with CT astringencies defined in vitro (P > 0.05). Astringency in vitro was defined as the mg of CT required to achieve half-maximal precipitation of 0.5 mg of protein (bovine serum albumin). In vitro, the most astringent CT (A. aneura 883558), had at least 1.6 times the astringency of the weakest CT (A. aneura 842394). The A. aneura with the weakest CT also contained less than 1/3 the total amount of CT/g leaf dry matter than that with the strongest, highlighting the scope for selection of more nutritionally useful types of A. aneura. Limitations of the in vivo protocol used are discussed and it is concluded

HPLC, NMR and MALDI-TOF MS analysis of condensed tannins from Lithocarpus glaber leaves with potent free radical scavenging activity.

Science.gov (United States)

Zhang, Liang Liang; Lin, Yi Ming

2008-12-04

Using acid-catalyzed degradation in the presence of cysteamine, the condensed tannins from Lithocarpus glaber leaves were characterized, following thiolysis, by means of reversed-phase HPLC, 13C-NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analyses. The thiolysis reaction products showed the presence of the procyanidin (PC) and prodelphinidin (PD) structures. The 13C-NMR spectrum revealed that the condensed tannins were comprised of PD (72.4%) and PC (27.6%), and with a greater content of cis configuration rather than the trans configuration of C2-C3. The MALDI-TOF MS analysis proved the presence of PD units, and the maximum degree of polymerization (DP) was an undecamer. The antioxidant activity of condensed tannins from L. glaber leaves was evaluated by using a free radical scavenging activity assay.

HPLC, NMR and MALDI-TOF MS Analysis of Condensed Tannins from Lithocarpus glaber Leaves with Potent Free Radical Scavenging Activity

OpenAIRE

Zhang, Liang Liang; Lin, Yi Ming

2008-01-01

Using acid-catalyzed degradation in the presence of cysteamine, the condensed tannins from Lithocarpus glaber leaves were characterized, following thiolysis, by means of reversed-phase HPLC, 13C-NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analyses. The thiolysis reaction products showed the presence of the procyanidin (PC) and prodelphinidin (PD) structures. The 13C-NMR spectrum revealed that the condensed tannins were comprised of PD (7...

The influence of condensed tannin structure on rate of microbial mineralization and reactivity to chemical assays.

Science.gov (United States)

Norris, Charlotte E; Preston, Caroline M; Hogg, Karen E; Titus, Brian D

2011-03-01

We examined how tannin structure influences reactivity in tannin assays and carbon and nitrogen mineralization. Condensed tannins from the foliage of ten tree and shrub species and from pecan shells (Carya illinoensis) had different proportions of: (a) epicatechin (cis) and catechin (trans) isomers, (b) procyanidin (PC) and prodelphinidin (PD) monomers, and (c) different chain lengths. The response of each tannin to several widely used tannin assays was determined. Although there was some variation in response to proanthocyanidin (butanol/HCl) and Folin Ciocalteu assays, we did not deduce any predictable relationship between tannin structure and response to either assay. There was little variation in protein precipitation among the different tannins. To assess biological activity, six of the tannins were incubated with forest humus for 22 days. We determined that, while PC-based tannins remained at least partly extractable for the duration of the incubation, tannins with a high proportion of PD subunits rapidly became unextractable from soil. There was a positive correlation between net nitrogen mineralization and cis chemical structure. Carbon mineralization was enhanced initially by the addition of tannins to humus, but after 22 days, a negative correlation between the proportion of cis subunits and respiration was determined. Overall, we were not able to demonstrate consistent effects of structure on either microbial mineralization or reactivity to chemical assays; such relationships remain elusive.

EXTRACTION AND ANALYSIS OF CONDENSED TANNINS IN CASTANEA SATIVA MILL.

OpenAIRE

J Živković; I Mujić; G Nikolić; S Vidović; A Mujić

2010-01-01

Proanthocyanidins, also known as condensed tannins are widespread in woody plants, but are also found in certain forages. Castanea sativa Mill. are exploited for various purposes, but a little is known about potential of this species and possible application in diet and therapy. The parts of chestnut such as: seed, peeled seed, brown seed shell, red internal seed shell, leaves, catkin, spiny bur, as well as the new and old chestnut bark were extracted with 50% ethanol as an extragents. Conten...

Seasonal regulation of condensed tannin consumption by free-ranging goats in a semiarid savanna

NARCIS (Netherlands)

Mkhize, Ntuthuko R.; Heitkönig, Ignas M.A.; Scogings, Peter F.; Hattas, Dawood; Dziba, Luthando E.; Prins, Herbert H.T.; Boer, De Willem F.

2018-01-01

Although condensed tannins (CTs) are known to reduce forage intake by mammalian herbivores in controlled experiments, few studies have tested these effects in the field. Thus the role of CTs on foraging ecology of free-ranging herbivores is inadequately understood. To investigate the effects of CTs

Inhibition of trypsin by condensed tannins and wine.

Science.gov (United States)

Gonçalves, Rui; Soares, Susana; Mateus, Nuno; de Freitas, Victor

2007-09-05

Phenolic compounds are abundant vegetable secondary metabolites in the human diet. The ability of procyanidin oligomers and wine polyphenols to inhibit trypsin activity was studied using a versatile and reliable in vitro method. The hydrolysis of the chromogenic substrate N-benzoyl-d,l-arginine-p-nitroanilide (BApNA) by trypsin was followed by spectrophotometry in the presence and absence of condensed tannins and wine. A clear relationship between the degree of polymerization of procyanidins and enzymatic inhibition was observed. Trypsin activity inhibition was also detected in several types of wine. In general, the inhibition increased with the concentration of phenolic compounds in wines. These results may be relevant when considering these compounds as antinutritional factors, thereby contributing to a reduced absorption of nutrients.

MALDI-TOF MS Analysis of Condensed Tannins with Potent Antioxidant Activity from the Leaf, Stem Bark and Root Bark of Acacia confusa

OpenAIRE

Wei; Zhou; Lin; Liao; Chai

2010-01-01

The structures of the condensed tannins from leaf, stem bark and root bark of Acacia confusa were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and their antioxidant activities were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. The results showed that the condensed tannins from stem bark and root bark include propelargonidin and procyanidi...

Condensed tannins: A novel rearrangement of procyanidins and prodelphinidins in thiolytic cleavage

Science.gov (United States)

G. Wayne McGraw; Jan P. Steynberg; Richard W. Hemingway

1993-01-01

Conditions commonly used for the thiolytic cleavage of interflavanoid bonds of condensed tannins also result in cleavage of the C4 to C10 bond of flavan units. Subsequenet lectrophilic attack of the C4 carbocation on the C2' or C6' of the B-ring, and loss of phloroglucinol (the A-ring), result in the formation of a mixture of 1,3-dithiobenzyl-2,4,s,6-...

Seasonal regulation of condensed tannin consumption by free-ranging goats in a semi-arid savanna

Science.gov (United States)

Heitkӧnig, Ignas M. A.; Scogings, Peter F.; Hattas, Dawood; Dziba, Luthando E.; Prins, Herbert H. T.; de Boer, Willem F.

2018-01-01

Although condensed tannins (CTs) are known to reduce forage intake by mammalian herbivores in controlled experiments, few studies have tested these effects in the field. Thus the role of CTs on foraging ecology of free-ranging herbivores is inadequately understood. To investigate the effects of CTs under natural savanna conditions, we pre-dosed groups of goats with polyethylene glycol (PEG, a CT-neutralising chemical), CT powder or water before observing their foraging behaviour. While accounting for the effects of season and time of the day, we tested the hypothesis that herbivores forage in ways that reduce the intake rate (g DM per minute) of CTs. We expected pre-dosing goats with CTs to reduce CT intake rates by (1) consuming diets low in CTs, (2) reducing bite rates, (3) increasing the number of foraging bouts, or (4) reducing the length of foraging bouts. Lastly, (5) expected CT to have no influence the number of dietary forage species. In both wet and dry seasons, pre-dosing goats with CTs resulted in lower CT consumption rates compared to PEG goats which seemed relieved from the stress associated with CT consumption. During dry season, the number of dietary forage species was similar across treatments, although goats that were dosed with PEG significantly increased this number in the wet season. Dosing goats with PEG increased the number and length of browsing bouts compared to goats from the other treatments. Pre-loading goats with PEG also tended to increase bite rates on browse forages, which contributed to increased consumption rates of CTs. Based on the behavioural adjustments made by goats in this study and within the constraints imposed by chemical complexity in savanna systems, we concluded that herbivores under natural conditions foraged in ways that minimised CTs consumption. More research should further elucidate the mechanism through which CTs regulated feeding behaviour. PMID:29293513

Quantification of tannins in tree and shrub foliage. A laboratory manual

International Nuclear Information System (INIS)

Makkar, H.P.S.

2003-01-01

Animal production systems in the tropical and subtropical countries utilize a wide range of feedstuffs; the main amongst these being the crop and industrial by-products, grasses, legumes, trees and shrubs. Trees and shrubs are of importance in animal production because they can provide significant protein supplements, especially in the dry season. But, the amount of tannins that they contain vary widely and largely unpredictably, and their effects on animals range from beneficial to toxicity and death. Similarly many agro-industrial by-products contain tannins. With a better understanding of tannin properties and proper management, they could become invaluable source of protein for strategic supplementation. As the demand for food rises, these unconventional feedstuffs must play an increasingly important part in the diet of animals, in particular for ruminants in small-holder farming in developing countries. It is therefore critical that proper techniques be used to measure and manage the anti-nutritional effects they cause. The analysis of tannins remains highly problematic. Various chemical assays for hydrolysable tannins and condensed tannins are available. Most tannin-containing feedstuffs contain both hydrolysable tannins and condensed tannins, but unfortunately only condensed tannins are generally analysed, probably because of simplicity of the assays measuring these; and the feedstuffs termed as tannin-containing or tannin-free feedstuffs. Furthermore, the biological effects are ascribed to mostly the condensed tannins (or the synonym: proanthocyanidins), which might be misleading. This paper reviews the available assays for hydrolysable tannins and condensed tannins and highlights the advantages and disadvantages of each. Protein precipitation assays, both isotopic and non-isotopic, representing the operational property of both hydrolysable tannins and condensed tannins; a tannin bioassay based on an in vitro simulation of the rumen and measurement of

Efficacy of condensed tannins against larval Hymenolepis diminuta (Cestoda) in vitro and in the intermediate host Tenebrio molitor (Coleoptera) in vivo.

Science.gov (United States)

Dhakal, Suraj; Meyling, Nicolai V; Williams, Andrew R; Mueller-Harvey, Irene; Fryganas, Christos; Kapel, Christian M O; Fredensborg, Brian L

2015-01-15

Natural anti-parasitic compounds in plants such as condensed tannins (CT) have anthelmintic properties against a range of gastrointestinal nematodes, but for other helminths such effects are unexplored. The aim of this study was to assess the effects of CT from three different plant extracts in a model system employing the rat tapeworm, Hymenolepis diminuta, in its intermediate host, Tenebrio molitor. An in vitro study examined infectivity of H. diminuta cysticercoids (excystation success) isolated from infected beetles exposed to different concentrations of CT extracts from pine bark (PB) (Pinus sps), hazelnut pericarp (HN) (Corylus avellana) or white clover flowers (WC) (Trifolium repens), in comparison with the anthelmintic drug praziquantel (positive control). In the in vitro study, praziquantel and CT from all three plant extracts had dose-dependent inhibitory effects on cysticercoid excystation. The HN extract was most effective at inhibiting excystation, followed by PB and WC. An in vivo study was carried out on infected beetles (measured as cysticercoid establishment) fed different doses of PB, HN and praziquantel. There was a highly significant inhibitory effect of HN on cysticercoid development (p=0.0002). Overall, CT showed a promising anti-cestodal effect against the metacestode stage of H. diminuta. Copyright © 2014 Elsevier B.V. All rights reserved.

Caractérisations physico-chimiques des tannins de Mangrove comme inhibiteurs de corrosion

OpenAIRE

Binti Abdui Rahim , Afidah

2005-01-01

Tannins from mangrove barks were extracted using 70% aqueous acetone and purification by chromatography afforded condensed tannins of high purity. The reversed-phase HPLC analysis of condensed tannins revealed mainly four flavanoïd monomers. Anti-oxidant capabilities were shown by mangrove tannins which were comparable to the standards. The electrochemical experiments have shown that the inhibitive efficiency of mangrove tannins on steel was largely contributed by the condensed tannins. Ali i...

Developing a conceptual model of possible benefits of condensed tannins for ruminant production.

Science.gov (United States)

Tedeschi, L O; Ramírez-Restrepo, C A; Muir, J P

2014-07-01

Enteric methane (CH4) emissions from ruminants have compelled a wide range of research initiatives to identify environmental abatement opportunities. However, although such mitigations can theoretically be attained with feed additives and feeding strategies, the limited empirical evidence on plant extracts used as feed additives does not support extensive or long-term reductions. Nevertheless, their strategic use (i.e. alone or combined in a simultaneous or consecutive use) may provide not only acceptable CH4 abatement levels, but also relevant effects on animal physiology and productivity. Condensed tannins (CT) represent a range of polyphenolic compounds of flavan-3-ol units present in some forage species that can also be added to prepared diets. Methods to determine CT, or their conjugated metabolites, are not simple. Although there are limitations and uncertainties about the methods to be applied, CT are thought to reduce CH4 production (1) indirectly by binding to the dietary fibre and/or reducing the rumen digestion and digestibility of the fibre and (2) directly by inhibiting the growth of rumen methanogens. On the basis of their role in livestock nutrition, CT influence the digestion of protein in the rumen because of their affinity for proteins (e.g. oxidative coupling and H bonding at neutral pH) that causes the CT-protein complex to be insoluble in the rumen; and dissociate in the abomasum at pH 2.5 to 3.0 for proteolysis and absorption in the small intestine. CT may also reduce gastro-intestinal parasite burdens and improve reproductive performance, foetal development, immune system response, hormone serum concentrations, wool production and lactation. The objectives of this paper are to discuss some of the beneficial and detrimental effects of CT on ruminant production systems and to develop a conceptual model to illustrate these metabolic relationships in terms of systemic physiology using earlier investigations with the CT-containing legume Lotus

Coupling of wet chemistry methods and spectroscopic data for elucidating composition and structure of purified condensed tannins

Science.gov (United States)

Condensed tannins (CTs) consist of oligomers and polymers of flavan-3-ol subunits varying in hydroxylation patterns, cis- and trans-configuration of C-ring substituents, interflavan bond connections, mean degree of polymerization (mDP), and extent of esterification. Robust analytical methods to dete...

Exploring the biological activity of condensed tannins and nutritional value of tree and shrub leaves from native species of the Argentinean Dry Chaco.

Science.gov (United States)

García, Elisa M; Cherry, Nicole; Lambert, Barry D; Muir, James P; Nazareno, Mónica A; Arroquy, Jose I

2017-11-01

Tropical tree or shrub leaves are an important source of nutrients for ruminants and a potential source of biologically active compounds that may affect ruminal metabolism of nutrients. Therefore, eight woody species from the native flora of Argentinean Dry Chaco, rich in secondary compounds such as condensed tannins (CT), were assessed for their nutritional value, CT fractions and in vitro true digestibility of dry matter, as well as biological activity (BA). Differences among species were found in contents of total phenol, protein-precipitating phenols (PPP), bound proteins to PPP (BP) and BP/PPP (P value and bioactivity among species. Those with the greatest CT were not necessarily those with the most BA. Caesalpinia paraguariensis, S. balansae and L. divaricata were the most promising species as native forage CT sources. Cercidiurm praecox (20.87% CP; 18.14% acid detergent fiber) and Prosopis nigra (19.00% CP; 27.96% acid detergent fiber) showed the best (P ≤ 0.05) nutritive values. According to their nutritive traits, these species might be complementary in grass-based ruminant diets. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Effects of condensed tannin fractions of different molecular weights from a Leucaena leucocephala hybrid on in vitro methane production and rumen fermentation.

Science.gov (United States)

Saminathan, Mookiah; Sieo, Chin Chin; Abdullah, Norhani; Wong, Clemente Michael Vui Ling; Ho, Yin Wan

2015-10-01

Molecular weights (MWs) and their chemical structures are the primary factors determining the influence of condensed tannins (CTs) on animal nutrition and methane (CH4 ) production in ruminants. In this study the MWs of five CT fractions from Leucaena leucocephala hybrid-Rendang (LLR) were determined and the CT fractions were investigated for their effects on CH4 production and rumen fermentation. The number-average molecular weight (Mn ) of fraction F1 (1265.8 Da), which was eluted first, was the highest, followed by those of fractions F2 (1028.6 Da), F3 (652.2 Da), F4 (562.2 Da) and F5 (469.6 Da). The total gas (mL g(-1) dry matter (DM)) and CH4 production decreased significantly (P fractions, but there were no significant (P > 0.05) differences between the CT fractions and control on DM degradation. However, the in vitro N disappearance decreased significantly (P fraction F1 (highest MW) compared with the control and other fractions (F2-F5). The inclusion of CT fraction F1 also significantly decreased (P fraction F1 but not by the control and other fractions (F2-F5). The CT fractions of different MWs from LLR could affect rumen fermentation and CH4 production, and the impact was more pronounced for the CT fraction with a higher MW. © 2014 Society of Chemical Industry.

Salivary amylase induction by tannin-enriched diets as a possible countermeasure against tannins

DEFF Research Database (Denmark)

da Costa, G; Lamy, E; Capela e Silva, F

2008-01-01

% hydrolyzable tannins (tannic acid), or diet with 5% condensed tannins (quebracho). Protein analysis was performed by one-dimensional gel electrophoresis combined with Matrix-Assisted Laser Desorption Ionization-Time of Flight mass spectrometry to allow the dynamic study of interactions between diet and saliva......Tannins are characterized by protein-binding affinity. They have astringent/bitter properties that act as deterrents, affecting diet selection. Two groups of salivary proteins, proline-rich proteins and histatins, are effective precipitators of tannin, decreasing levels of available tannins....... The possibility of other salivary proteins having a co-adjuvant role on host defense mechanisms against tannins is unknown. In this work, we characterized and compared the protein profile of mice whole saliva from animals fed on three experimental diets: tannin-free diet, diet with the incorporation of 5...

A genomics investigation of partitioning into and among flavonoid-derived condensed tannins for carbon sequestration in Populus

Energy Technology Data Exchange (ETDEWEB)

Harding, Scott, A; Tsai, Chung-jui; Lindroth, Richard, L

2013-03-24

The project set out to use comparative (genotype and treatment) and transgenic approaches to investigate the determinants of condensed tannin (CT) accrual and chemical variability in Populus. CT type and amount are thought to effect the decomposition of plant detritus in the soil, and thereby the sequestering of carbon in the soil. The stated objectives were: 1. Genome-wide transcriptome profiling (microarrays) to analyze structural gene, transcription factor and metabolite control of CT partitioning; 2. Transcriptomic (microarray) and chemical analysis of ontogenetic effects on CT and PG partitioning; and 3. Transgenic manipulation of flavonoid biosynthetic pathway genes to modify the control of CT composition. Objective 1: A number of approaches for perturbing CT content and chemistry were tested in Objective 1, and those included nitrogen deficit, leaf wounding, drought, and salicylic acid spraying. Drought had little effect on CTs in the genotypes we used. Plants exhibited unpredictability in their response to salicylic acid spraying, leading us to abandon its use. Reduced plant nitrogen status and leaf wounding caused reproducible and magnitudinally striking increases in leaf CT content. Microarray submissions to NCBI from those experiments are the following: GSE ID 14515: Comparative transcriptomics analysis of Populus leaves under nitrogen limitation: clone 1979. Public on Jan 04, 2010; Contributor(s) Harding SA, Tsai C GSE ID 14893: Comparative transcriptomics analysis of Populus leaves under nitrogen limitation: clone 3200. Public on Feb 19, 2009; Contributor(s) Harding SA, Tsai C GSE ID 16783 Wound-induced gene expression changes in Populus: 1 week; clone RM5. Status Public on Dec 01, 2009; Contributor(s) Harding SA, Tsai C GSE ID 16785 Wound-induced gene expression changes in Populus: 90 hours; clone RM5 Status Public on Dec 01, 2009; Contributor(s) Harding SA, Tsai C Although CT amount changed in response to treatments, CT composition was essentially

Tannin diagenesis in mangrove leaves from a tropical estuary: a novel molecular approach

Science.gov (United States)

Hernes, Peter J.; Benner, Ronald; Cowie, Gregory L.; Goñi, Miguel A.; Bergamaschi, Brian A.; Hedges, John I.

2001-09-01

Molecular-level condensed tannin analyses were conducted on a series of mangrove (Rhizophora mangle) leaves at various stages of decomposition in a tropical estuary. Total molecular tannin yields ranged from 0.5% ash-free dry weight (AFDW) in the most highly degraded black leaves (6-7 weeks in the water) up to >7% AFDW in fresh leaves (80% procyanidin (PC) with the remainder being prodelphinidin (PD). PD tannin, with its higher degree of hydroxylation, proved to be more labile than PC tannin. Average chain length of condensed tannin (degree of polymerization) exhibited an initial increase in response to leaching, but later decreased in the subsequent shift toward abiotic or microbially mediated chemical reactions. Several trends point toward a possible condensation reaction in which tannin plays a role in nitrogen immobilization. These include an apparent inverse correlation between molecular tannin and nitrogen, a positive correlation between molecular tannin and percent basic amino acids, 13C-NMR data indicating transformation of tannin as opposed to remineralization, and 13C-NMR data showing loss of condensed tannin B-ring phenolic carbons coupled with preservation of A-ring phenolic carbon. In addition to condensed tannin, the molecular method used also yielded several triterpenoids. Triterpenoids accounted for up to 3.5% AFDW of the leaf material and exhibited a threefold increase between yellow senescent leaves entering the estuary and black leaves. This trend is likely due to the weakening of protective cuticular membranes during leaf decomposition, which leads to increased yields in the acidic conditions used for tannin analyses.

Composition and structural features of condensed tannins from Texas legumes exhibiting methane abatement activity during in vitro rumen digestion

Science.gov (United States)

Previous studies showed that a series of purified condensed tannins (CTs) from warm-season perennial legumes exhibited high variability in their modulation of methane production during in vitro rumen digestion. The molecular weight difference of these CTs did not provide correlation with either the ...

Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

Energy Technology Data Exchange (ETDEWEB)

Yusof, Mohd Fahmi Mohd, E-mail: mfahmi@usm.my; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, Sabar [School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, Rokiah [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia)

2015-04-29

Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ{sup 2} value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ{sup 2} value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

International Nuclear Information System (INIS)

Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz; Bauk, Sabar; Hashim, Rokiah

2015-01-01

Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ 2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ 2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies

Physicochemical Quality, Fatty Acid Composition, and Sensory Analysis of Nellore Steers Meat Fed with Inclusion of Condensed Tannin in the Diet.

Science.gov (United States)

Gesteira, Susana M; Oliveira, Ronaldo L; Silva, Thadeu M; Ribeiro, Rebeca D X; Ribeiro, Cláudio V D M; Pereira, Elzania S; Lanna, Dante P D; Pinto, Luis F B; Rocha, Tiago C; Vieira, Jusaline F; Bezerra, Leilson R

2018-05-01

This study was conducted to test the effect of dietary tannin on the fatty acid profile and sensory attributes of meat from Nellore steers. Thirty-two Nellore bull male were distributed in a completely randomized design and fed diets with condensed tannin extract as follows: 0, 10, 30, and 50 g/kg total DM basis. The physicochemical composition of the meat, lipid oxidation, fatty acid profile, flavor, tenderness, and overall acceptance were evaluated. There was a linear decrease (P ≤ 0.05) on lipid content, tenderness, cooking weight loss, myristic, palmitic, and oleic acids in meat as tannin increased in the diets. The total saturated and monounsaturated fatty acids, the atherogenicity index decreased. However, a linear increase (P ≤ 0.05) was observed for linoleic, linolenic, arachidonic, eicosapentaenoic, and docosapentaenoic acids. The physicochemical characteristic of the meat, such as moisture, ash, and protein contents, water retention capacity, final pH, Warner-Bratzler shear force, collagen, and color indexes (lightness, redness, yellowness, and chrome) did not change with dietary tannin. Also, CLA, n-6:n-3 ratio, Δ 9 -desaturase, and elongase activity were not different among diets. In conclusion, condensed tannin linearly increases unsaturated fatty acids and decreases the atherogenicity index of meat; thus, it can be recommended at the highest level (50 g/kg DM) in the diet of Nellore steers. Agriculture byproducts plays an important part in the diet of ruminant animals and consequently on food chain and has implications for the composition and quality of the livestock products (milk, meat, and eggs) that people consume. Feeding tannin to steers increases the amount of unsaturated fatty acids and meat tenderness, with a concomitant reduction on saturated fatty acids and the atherogenicity index in meat. Thus, we recommend adding tannin to steer diets to reduce the risk factors for cardiovascular diseases in red meat for human consumption. �

Effects of condensed tannins supplementation level on weight gain and in vitro and in vivo bloat precursors in steers grazing winter wheat.

Science.gov (United States)

Min, B R; Pinchak, W E; Anderson, R C; Fulford, J D; Puchala, R

2006-09-01

Research was conducted to determine the effects of level of supplementation with quebracho condensed tannins (CT) on in vitro ruminal fluid gas production, in vivo ruminal fluid protein fractions, bloat dynamics, and ADG of steers grazing winter wheat. Two experiments were conducted to 1) enumerate the effect of ruminal fluid from steers fed quebracho CT (0, 1, and 2% CT/kg of DMI) on in vitro gas and methane production from minced fresh wheat forage; and 2) quantify the influence of CT supplementation on ruminal protein characteristics, biofilm complexes, bloat potential, and ADG of steers grazing wheat pasture. Eighteen ruminally cannulated steers (386 +/- 36 kg of BW) were randomly allocated to 1 of 3 treatments that included a control (water infusion) and 2 CT treatment levels (1 or 2% CT/kg of DMI). Treatments were administered daily (63 d) through the rumen cannula as pre-mixes with warm water (approximately 30 degrees C). Rumen contents were collected 2 h postinfusion (at 1030 to 1130) on d 0, 20, 40, 50, and 60. Bloat was visually scored daily for 5 d each wk. In Exp. 1, supplementation of CT decreased the rate of in vitro gas production in a dose-dependent response. In Exp. 2, ADG increased (P bloat score across stage of growth and replicates decreased linearly with increasing CT supplementation; bloat scores were greater (P rumen fluid protein fractions varied among CT treatments and stage of growth. Addition of CT reduced the severity of bloat, principally through reducing microbial activities, biofilm production, and ruminal gas production. Quebracho CT is potentially a value-added supplement that can decrease the impacts of frothy bloat and increase BW gains in stocker cattle-wheat systems.

Interactions of Condensed Tannins with Saccharomyces cerevisiae Yeast Cells and Cell Walls: Tannin Location by Microscopy.

Science.gov (United States)

Mekoue Nguela, Julie; Vernhet, Aude; Sieczkowski, Nathalie; Brillouet, Jean-Marc

2015-09-02

Interactions between grape tannins/red wine polyphenols and yeast cells/cell walls was previously studied within the framework of red wine aging and the use of yeast-derived products as an alternative to aging on lees. Results evidenced a quite different behavior between whole cells (biomass grown to elaborate yeast-derived products, inactivated yeast, and yeast inactivated after autolysis) and yeast cell walls (obtained from mechanical disruption of the biomass). Briefly, whole cells exhibited a high capacity to irreversibly adsorb grape and wine tannins, whereas only weak interactions were observed for cell walls. This last point was quite unexpected considering the literature and called into question the real role of cell walls in yeasts' ability to fix tannins. In the present work, tannin location after interactions between grape and wine tannins and yeast cells and cell walls was studied by means of transmission electron microscopy, light epifluorescence, and confocal microscopy. Microscopy observations evidenced that if tannins interact with cell walls, and especially cell wall mannoproteins, they also diffuse freely through the walls of dead cells to interact with their plasma membrane and cytoplasmic components.

Condensed Tannins in the Gastrointestinal Tract of Cattle after Sainfoin (Onobrychis viciifolia) Intake and Their Possible Relationship with Anthelmintic Effects

DEFF Research Database (Denmark)

Desrues, Olivier; Mueller-Harvey, Irene; Pellikaan, Wilbert F

2017-01-01

Condensed tannins' (CTs) fate along the digestive tract of ruminants may account for the variable efficacy of CTs against gastrointestinal nematodes. We analyzed CTs in the digesta of cattle fed sainfoin. With the acetone-butanol-HCl assay, the total CTs concentrations in the digesta were close...

Growth of broiler chicks fed diets containing tannin-free and tannin-containing near-isogenic lines of Faba bean (Vicia Faba L.).

NARCIS (Netherlands)

Helsper, J.P.F.G.; Loon, van Y.P.J.; Kwakkel, R.P.; Norel, van A.; Poel, van der A.F.B.

1996-01-01

Seeds from six pairs of near-isogenic lines of Vicia faba L., each pair consisting of a tannin-free (TF) and a tannin-containing (TC) partner line, were used to study the effect of breeding for the absence of condensed tannins on the seed content of dry matter (DM), crude protein (CP), and starch

The inhibitory potential of the condensed-tannin-rich fraction of Plathymenia reticulata Benth. (Fabaceae) against Bothrops atrox envenomation.

Science.gov (United States)

de Moura, Valéria Mourão; da Silva, Wania Cristina Rodrigues; Raposo, Juliana D A; Freitas-de-Sousa, Luciana A; Dos-Santos, Maria Cristina; de Oliveira, Ricardo Bezerra; Veras Mourão, Rosa Helena

2016-05-13

Ethnobotanical studies have shown that Plathymenia reticulata Benth. (Fabaceae) has been widely used in cases of snake envenomation, particularly in Northern Brazil. In light of this, the aim of this study was to evaluate the inhibitory potential of the condensed-tannin-rich fraction obtained from the bark of P. reticulata against the main biological activities induced by Bothrops atrox venom (BaV). The chemical composition of the aqueous extract of P. reticulata (AEPr) was first investigated by thin-layer chromatography (TLC) and the extract was then fractionated by column chromatography on Sephadex LH-20. This yielded five main fractions (Pr1, Pr2, Pr3, Pr4 and Pr5), which were analyzed by colorimetry to determine their concentrations of total phenolics, total tannins and condensed tannins and to assess their potential for blocking the phospholipase activity of BaV. The Pr5 fraction was defined as the fraction rich in condensed tannins (CTPr), and its inhibitory potential against the activities of the venom was evaluated. CTPr was evaluated in different in vivo and in vitro experimental protocols. The in vivo protocols consisted of (1) pre-incubation (venom:CTPr, w/w), (2) pre-treatment (orally administered) and (3) post-treatment (orally administered) to evaluate the effect on the hemorrhagic and edematogenic activities of BaV; in the in vitro protocol the effect on phospholipase and coagulant activity using pre-incubation in both tests was evaluated. There was statistically significant inhibition (p<0.05) of hemorrhagic activity by CTPr when the pre-incubation protocol was used [55% (1:5, w/w) and 74% (1:10, w/w)] and when pre-treatment with doses of 50 and 100mg/kg was used (19% and 13%, respectively). However, for the concentrations tested, there was no statistically significant inhibition in the group subjected to post-treatment administered orally. CTPr blocked 100% of phospholipase activity and 63.3% (1:10, w/w) of coagulant activity when it was pre

Attempts to deactivate tannins in fodder shrubs with physical and chemical treatments

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Saghrouni, L. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia); Nefzaoui, A. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)

2005-08-19

Chopping, water sprinkling, storage under aerobic and anaerobic conditions, urea, wood ash, activated charcoal and polyethylene glycol 4000 (PEG) treatments were evaluated for their efficiency in deactivating tannins in shrub foliage. In a first trial, fresh leaves of Acacia cyanophylla Lindl. (acacia) were stored after chopping or without chopping and spraying or without spraying with water under aerobic or anaerobic conditions. The plant material was stored for 1, 7 and 14 days and analysed thereafter for extractable total phenols (TP), extractable total tannins (TT) and extractable condensed tannins (CT) contents. Chopping and water spraying substantially decreased the levels of TP, TT and CT of acacia. The rate of tannin deactivation increased in acacia stored under anaerobic conditions. Acacia stored for 7 days exhibited lower TP, TT and CT contents than that stored for only 1 day. Compared to the 7-day storage period, there was a further non-significant decrease in the level of these phenolic compounds when the storage duration was extended to 14 days. The highest level of rumen degradation of crude protein (CP) in sheep rumen was obtained with chopped, water sprinkled acacia leaves stored under anaerobic conditions. The second trial investigated the effect of increasing levels of urea (0, 20, 40, 60 and 80 g/kg) and treatment duration (7, 14, 21 and 28 days) on CP, TP, TT and CT in acacia leaves. The 20 g/kg urea level was sufficient to totally deactivate tannins in acacia even with the shortest storage period, i.e. 7 days. However, urea treatment increased ash-free neutral detergent fibre content and did not improve in sacco acacia degradation. In the third trial air-dried 1 mm ground samples of acacia and kermes oak (Quercus coccifera L.) leaves were added to water (control), acacia wood ash, activated charcoal or PEG solutions (100 g/kg) at 1:10 (w/v) and shaken for 20 min. All these four treatments decreased TP, TT and CT contents and could be classified

缩合单宁对反刍动物瘤胃发酵的影响与研究进展%Research Progress on Effects of Condensed Tannins on Rumen Fermentation

Institute of Scientific and Technical Information of China (English)

邱清华

2016-01-01

Condensed tannin are found in many forage plants as a common anti-nutritional factor. Recent researches on ruminants found condensed tannins showed nutritional functions in increasing rumen bypass protein, controlling methane emissions and controling rumen fermentation. This paper reviews the effect of condensed tannins on the structure of ruminal microflora, pH, ammonia nitrogen, methane production and production of microbial crude protein. New research directions and prospects of condensed tannins were proposed as well.%缩合单宁作为一种常见的抗营养因子，存在于众多饲草植物中。近年来在反刍动物上的研究发现缩合单宁在提高过瘤胃蛋白、控制甲烷排放以及调控瘤胃发酵方面表现出营养作用。本文综述了缩合单宁对瘤胃微生物区系结构、pH、甲烷产量、氨态氮以及微生物蛋白含量的影响，并提出了缩合单宁新的研究方向和应用前景。

Salivary amylase induction by tannin-enriched diets as a possible countermeasure against tannins.

Science.gov (United States)

da Costa, G; Lamy, E; Capela e Silva, F; Andersen, J; Sales Baptista, E; Coelho, A V

2008-03-01

Tannins are characterized by protein-binding affinity. They have astringent/bitter properties that act as deterrents, affecting diet selection. Two groups of salivary proteins, proline-rich proteins and histatins, are effective precipitators of tannin, decreasing levels of available tannins. The possibility of other salivary proteins having a co-adjuvant role on host defense mechanisms against tannins is unknown. In this work, we characterized and compared the protein profile of mice whole saliva from animals fed on three experimental diets: tannin-free diet, diet with the incorporation of 5% hydrolyzable tannins (tannic acid), or diet with 5% condensed tannins (quebracho). Protein analysis was performed by one-dimensional gel electrophoresis combined with Matrix-Assisted Laser Desorption Ionization-Time of Flight mass spectrometry to allow the dynamic study of interactions between diet and saliva. Since abundant salivary proteins obscure the purification and identification of medium and low expressed salivary proteins, we used centrifugation to obtain saliva samples free from proteins that precipitate after tannin binding. Data from Peptide Mass Fingerprinting allowed us to identify ten different proteins, some of them showing more than one isoform. Tannin-enriched diets were observed to change the salivary protein profile. One isoform of alpha-amylase was overexpressed with both types of tannins. Aldehyde reductase was only identified in saliva of the quebracho group. Additionally, a hypertrophy of parotid salivary gland acini was observed by histology, along with a decrease in body mass in the first 4 days of the experimental period.

Improving Water Repellence and Friability of Tannin-Furanic Foams by Oil-Grafted Flavonoid Tannins

Directory of Open Access Journals (Sweden)

Géraldine Rangel

2016-08-01

Full Text Available Tannin-furanic biobased foams, based on the co-reaction of bark-derived condensed tannins and thermoset furanic polymers, have low thermal conductivity, are self-extinguishing, and have high fire resistance, which allows their development for several industrial uses. One of their main drawbacks, however, is the absorption of water within the foam itself. Another problem is the rather friable surface, which is a definite drawback for some potential applications. In this work, these two problems are minimized or eliminated by introducing a component of oil-grafted tannin in the foam formulation. The incorporation of fatty chains markedly decreased foam friability and increased water repellency in the body of the foams. These properties and the compounds formed by fatty acids grafting onto the tannin flavonoids were extensively tested.

Condensed tannins: Base-catalysed reactions of polymeric procyanidins with toluene-α-thiol, liability of the interflavanoid bond and pyran ring

Science.gov (United States)

Peter E. Laks; Richard W. Hemingway

1987-01-01

Reaction of polymeric procyanidins (condensed tannins) with toluene-α-thiol at pH 12.0 and 23°C gave predominantly one stereoisomer of 1.3-bisbenzylthio-1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl) propan-2-ol (10) by stereoselective reaction at C-4 and C-2 of the Quinone methide derived from the upper 2,3-cis procyanidin units....

Tannins in faba beans (Vicia faba L.) : antinutritional properties in monogastric animals

NARCIS (Netherlands)

Jansman, A.J.M.

1993-01-01

Condensed tannins are found in coloured-flowering varieties of faba beans ( Viciafaba L.). They are considered as antinutritional factors for nonruminant species. High-tannin hulls of faba beans and isolated tannins were shown to induce a rapid

Effect of condensed tannins from Ficus infectoria and Psidium guajava leaf meal mixture on nutrient metabolism, methane emission and performance of lambs.

Science.gov (United States)

Pathak, A K; Dutta, Narayan; Pattanaik, A K; Chaturvedi, V B; Sharma, K

2017-12-01

The study examined the effect of condensed tannins (CT) containing Ficus infectoria and Psidium guajava leaf meal mixture (LMM) supplementation on nutrient metabolism, methane emission and performance of lambs. Twenty four lambs of ~6 months age (average body weight 10.1±0.60 kg) were randomly divided into 4 dietary treatments (CT-0, CT-1, CT-1.5, and CT-2 containing 0, 1.0, 1.5, and 2.0 percent CT through LMM, respectively) consisting of 6 lambs each in a completely randomized design. All the lambs were offered a basal diet of wheat straw ad libitum, oat hay (100 g/d) along with required amount of concentrate mixture to meet their nutrient requirements for a period of 6 months. After 3 months of experimental feeding, a metabolism trial of 6 days duration was conducted on all 24 lambs to determine nutrient digestibility and nitrogen balance. Urinary excretion of purine derivatives and microbial protein synthesis were determined using high performance liquid chromatography. Respiration chamber study was started at the mid of 5th month of experimental feeding trial. Whole energy balance trials were conducted on individual lamb one after the other, in an open circuit respiration calorimeter. Intake of dry matter and organic matter (g/d) was significantly (p<0.05) higher in CT-1.5 than control. Digestibility of various nutrients did not differ irrespective of treatments. Nitrogen retention and microbial nitrogen synthesis (g/d) was significantly (p<0.01) higher in CT-1.5 and CT-2 groups relative to CT-0. Total body weight gain (kg) and average daily gain (g) were significantly (linear, p<0.01) higher in CT-1.5 followed by CT-1 and CT-0, respectively. Feed conversion ratio (FCR) by lambs was significantly (linear, p<0.01) better in CT-1.5 followed by CT-2 and CT-0, respectively. Total wool yield (g; g/d) was linearly (p<0.05) higher for CT-1.5 than CT-0. Methane emission was linearly decreased (p<0.05) in CT groups and reduction was highest (p<0.01) in CT-2 followed by

Tannins in faba beans (Vicia faba L.) : antinutritional properties in monogastric animals

NARCIS (Netherlands)

Jansman, A.J.M.

1993-01-01

Condensed tannins are found in coloured-flowering varieties of faba beans ( Viciafaba L.). They are considered as antinutritional factors for nonruminant species. High-tannin hulls of faba beans and isolated tannins were shown to induce a rapid hypertrophy of the parotid glands in rats and increase

A study on the effect of levels of tannins on in vitro digestibility of different Sudanese varieties of sorghum grains

International Nuclear Information System (INIS)

Mohammed, M.A.

2008-06-01

This work was conducted to evaluate the tannin content and its effect on ruminant's digestibility in 26 Sudanese sorghum varieties. Samples were brought from Agricultural Research Corporation, Wad Medani (ARC), hand cleaned and preserved in dark in plastic containers. Tannins content was measured by using vanillin-HCl method (Price et al, 1979) and in vitro digestibility was conducted to evaluate the dry meter digestibility and organic matter digestibility according to (Tilley and Terry, 1963). Results have shown that condensed tannins (vanillin-HCl) ranged between 0.39 g/kg and 23.08 g/kg, Tabat recorded the lowest value when Wad akar red recorded the highest value. An in vitro dry matter digestibility (INVDMD) and organic matter digestibility (OMD) trial were performed. There was a negative correlation (P<0.05) between organic matter and condensed tannins especially those contained high level of condensed tannins. The organic matter digestibility ranged between 680.11 g/kg in arfa gadamak commercial to 828.85 g/kg in dar baladi. The results have shown that the addition of polyethylene glycol (PEG) to in vitro incubated samples increased the gas produced in wad akar red in 24 hours by 29% compared to the control sample without (PEG). Higher significant correlation (P<0.001) between the clorox bleaching test and condensed tannins (vanillin-HCl) in samples was found. It is concluded that condensed tannins in sorghum are beneficial to ruminant when they are introduced in complete diets to avoid the inhibitory effects of condensed tannins in sorghum. Adding (PEG) to the ruminant diets which contain high levels of condensed tannins improved digestibility subsequently animal performance.(Author)

A study on the effect of levels of tannins on in vitro digestibility of different Sudanese varieties of sorghum grains

Energy Technology Data Exchange (ETDEWEB)

Mohammed, M A [Animal Resources Research Council, Sudan Academy of Sciences, Khartoum (Sudan)

2008-06-15

This work was conducted to evaluate the tannin content and its effect on ruminant's digestibility in 26 Sudanese sorghum varieties. Samples were brought from Agricultural Research Corporation, Wad Medani (ARC), hand cleaned and preserved in dark in plastic containers. Tannins content was measured by using vanillin-HCl method (Price et al, 1979) and in vitro digestibility was conducted to evaluate the dry meter digestibility and organic matter digestibility according to (Tilley and Terry, 1963). Results have shown that condensed tannins (vanillin-HCl) ranged between 0.39 g/kg and 23.08 g/kg, Tabat recorded the lowest value when Wad akar red recorded the highest value. An in vitro dry matter digestibility (INVDMD) and organic matter digestibility (OMD) trial were performed. There was a negative correlation (P<0.05) between organic matter and condensed tannins especially those contained high level of condensed tannins. The organic matter digestibility ranged between 680.11 g/kg in arfa gadamak commercial to 828.85 g/kg in dar baladi. The results have shown that the addition of polyethylene glycol (PEG) to in vitro incubated samples increased the gas produced in wad akar red in 24 hours by 29% compared to the control sample without (PEG). Higher significant correlation (P<0.001) between the clorox bleaching test and condensed tannins (vanillin-HCl) in samples was found. It is concluded that condensed tannins in sorghum are beneficial to ruminant when they are introduced in complete diets to avoid the inhibitory effects of condensed tannins in sorghum. Adding (PEG) to the ruminant diets which contain high levels of condensed tannins improved digestibility subsequently animal performance.(Author)

The first C4-functionalisation of condensed tannins. Phlobatannins as prototype of a new class of C-ring isomerised oligomers

International Nuclear Information System (INIS)

Steenkamp, J.A.

1986-06-01

This thesis comprises besides the characterisation of new oligomeric flavenoids from the core wood of the indigeneous Colophosphermum mopane, an investigation into the C 4 -functionalisation of flavan-3-ol analogues. The first peltogynoid biflavenoid and prototypes of a new series C-ring isomerised condensed tannins, namely the phlobatannins, were isolated. Besides 1 H- nmr-parameters for structure analysis, the natural phlobatannins were characterised and the unique ring isomerisation was investigated

The effect of different detanninfication effects on the tannins found in ...

African Journals Online (AJOL)

200604877

2013-12-18

Dec 18, 2013 ... Int. J. Crude Drug Res. 23, 87-90. Barry, T.N. ... Analysis of condensed tannins using Acidified Vanillin. J. Sci. Food. Agr. 29, 788-794. .... Interactions among tannins, supplementation and polyethylene glycol in goats given oak ...

Use of Soy Flour-Tannin Adhesive for Particleboard (Dry Condition

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Saman Ghahri

2017-05-01

Full Text Available In this research soy flour- tannin adhesives were used in particleboard preparation, successfully. Tow type of different tannins Mimosa (as condensed tannin and Chestnut (as hydrolysable tannins were used for soy resin modification. For this purpose, mimosa and chestnut tannin were added to soy adhesive with 5, 10 and 15 percent based on dry weight of soy flour. 9 percent Glyoxal was used based on dry weight of tannin for accelerate tannin reaction’s with soyflour components. Prepared soy-tannin adhesives were used in particle board manufacturing with 350×300×14 mm3 dimansion and 0.7 g/cm3 nominal density. Results of viscosity measurment showed that addition of each of tannins decreased visocosity of soy adhesive. In this study, result of thermo-mechanical analyze indicated that chestnut cloud improve adhesion behavior of soy adhesive better than mimosa. Also, Using of tannins in soy adhesive composition increase internal bonding and bending properties in manufactured particleboards.

Modulation of in vitro rumen biohydrogenation by Cistus ladanifer tannins compared with other tannin sources.

Science.gov (United States)

Costa, Mónica; Alves, Susana P; Cabo, Ângelo; Guerreiro, Olinda; Stilwell, George; Dentinho, Maria T; Bessa, Rui Jb

2017-01-01

Tannins are polyphenolic compounds able to modify the ruminal biohydrogenation (BH) of unsaturated fatty acids, but their activity may vary among different tannin sources. The effect of rockrose (Cistus ladanifer) on BH has never been compared with other more common tannin sources. Tannin extracts (100 g kg -1 substrate dry matter) from chestnut (CH), quebracho (QB), grape seed (GS) and rockrose (CL) were incubated in vitro for 6 h with ruminal fluid using as substrate a feed containing 60 g kg -1 of sunflower oil. A control treatment with no added tannins was also included. Compared with the control, GS and CL, but not CH and QB, increased (P 0.05) were observed for the disappearance of c9-18:1 and c9,c12,c15-18:3. The production of 18:0 was not different (P > 0.05) among treatments, although its proportion in the total BH products was lower (P < 0.05) for GS than for the other treatments. Condensed tannins from GS and, to a lesser extent, from CL stimulate the first steps of BH, without a clear inhibition of 18:0 production. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

[Comparative study of different extraction methods and assays of tannins in some pteridophytes].

Science.gov (United States)

Laurent, S

1975-10-01

Various processes of extraction and quantitative analysis of a condensed tannin in a plant extract, which also includes some chlorogenic acids, have been examined. 60% methanol, at 50 degrees C, proved the most efficient extraction solvent. Several methods of analysis have been tried. The measure of the colour intensity obtained by the action of sulphuric vanilline on flavanols cannot be used because it depends on the tannin condensation stage. It is impossible to separate tannin from chlorogenic acids using the methods of adsorption by skin or nylon powders, or precipitation by polyvinylpyrrolidone. Only paper chromatography, followed by the distinct elution of the various phenolic compounds, allows the tannin evaluation by subtraction; but owing to the variability of the results, many more experiments are necessary. Some other processes are being studied.

Effect of the prefermentative addition of five enological tannins on anthocyanins and color in red wines.

Science.gov (United States)

Liu, Yan-Xia; Liang, Na-Na; Wang, Jun; Pan, Qiu-Hong; Duan, Chang-Qing

2013-01-01

The effects of prefermentation addition of 5 exogenous tannins with different-origin anthocyanins and color characteristics were investigated in "Cabernet Sauvignon wines" at the end of alcoholic fermentation and the end of malolactic fermentation, and after 6 mo and 9 mo of bottle aging, respectively. The results showed that the application of GSKT2 could significantly retard the degradation of most anthocyanins in the process of alcoholic fermentation and the decrease of some pyranoanthocyanins during the subsequent 3 stages, thus causing more yellowness of wine in comparison with the control. Three other condensed tannins, GSKT1, QUET, and GSET, had a positive impact only on several anthocyanin components. Four condensed tannins all contributed to more redness, suggesting that the action mechanism might be to protect wine against oxidation or contribute to form copigmented anthocyanidins, or polymeric pigments. The application of FOLT (hydrolysable tannin) did not produce any influence on wine redness even after 9 mo of bottle aging. This work provides some reasons for the reasonable application of tannin additives. The prefermentative application of condensed tannins overall could protect some pigment components from degradation and enhance wine redness. Tannin additives with different origins have different effectiveness. The tannin additive obtained from grape skins, like GSKT2, could produce significant promotion on both redness and yellowness in wine. The prefermentation addition of hydroxylase tannin like FOLT seems not to have a significant effect on wine color. © 2012 Institute of Food Technologists®

The effect of tannin with and without polyethylene glycol on in vitro ...

African Journals Online (AJOL)

PEG also increased the activity of protease enzymes, xylanase, endo- and exocellulases, indicating that tannins depress the digestibility of feeds partly by suppressing the activity of these enzymes. Consequently, condensed tannin depressed the digestibility of feed in the rumen by affecting the activity of enzymes involved ...

Potential of tannin-rich plants for modulating ruminal microbes and ruminal fermentation in sheep.

Science.gov (United States)

Rira, M; Morgavi, D P; Archimède, H; Marie-Magdeleine, C; Popova, M; Bousseboua, H; Doreau, M

2015-01-01

The objective of this work was to study nutritional strategies for decreasing methane production by ruminants fed tropical diets, combining in vitro and in vivo methods. The in vitro approach was used to evaluate the dose effect of condensed tannins (CT) contained in leaves of Gliricidia sepium, Leucaena leucocephala, and Manihot esculenta (39, 75, and 92 g CT/kg DM, respectively) on methane production and ruminal fermentation characteristics. Tannin-rich plants (TRP) were incubated for 24 h alone or mixed with a natural grassland hay based on Dichanthium spp. (control plant), so that proportions of TRP were 0, 0.25, 0.5, 0.75, and 1.0. Methane production, VFA concentration, and fermented OM decreased with increased proportions of TRP. Numerical differences on methane production and VFA concentration among TRP sources may be due to differences in their CT content, with greater effects for L. leucocephala and M. esculenta than for G. sepium. Independently of TRP, the response to increasing doses of CT was linear for methane production but quadratic for VFA concentration. As a result, at moderate tannin dose, methane decreased more than VFA. The in vivo trial was conducted to investigate the effect of TRP on different ruminal microbial populations. To this end, 8 rumen-cannulated sheep from 2 breeds (Texel and Blackbelly) were used in two 4 × 4 Latin square designs. Diets were fed ad libitum and were composed of the same feeds used for the in vitro trial: control plant alone or combined with pellets made from TRP leaves at 44% of the diet DM. Compared to TRP, concentration of Ruminococcus flavefaciens was greater for the control diet and concentration of Ruminococcus albus was least for the control diet. The methanogen population was greater for Texel than for Blackbelly. By contrast, TRP-containing diets did not affect protozoa or Fibrobacter succinogenes numbers. Hence, TRP showed potential for mitigating methane production by ruminants. These findings suggest

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency

OpenAIRE

Ma, Wen; Waffo-Teguo, Pierre; Jourdes, Michael; Li, Hua; Teissedre, Pierre-Louis

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly ...

Extraction and identification of tannins from the stems of Geum urbanum L.

OpenAIRE

Rams, Mette; Pyndt Andersen, Mikkel; Nørgaard Bachmann, Helene

2011-01-01

A common cause of cancer is oxidative damage to cells due to decreased conversion of reactive oxygen species (ROS). Hence compounds with antioxidant activities are of great interest. Hydrolyzable and condensed tannins are known to have antioxidant effects and have been found in several plants. We examined dried stems of Geum urbanum L. and detected tannins using thin layer chromatography (TLC). We separated the tannins using three types of columns; Sephadex LH-20, partition column chromatogra...

Effects of tropical high tannin non legume and low tannin legume browse mixtures on fermentation parameters and methanogenesis using gas production technique.

Science.gov (United States)

Seresinhe, T; Madushika, S A C; Seresinhe, Y; Lal, P K; Orskov, E R

2012-10-01

In vitro experiments were conducted to evaluate the suitability of several mixtures of high tanniniferous non legumes with low tanniniferous legumes on in vitro gas production (IVGP), dry matter degradation, Ammonia-N, methane production and microbial population. Eight treatments were examined in a randomized complete block design using four non-legumes and two legumes (Carallia integerrima×Leucaena leucocephala (LL) (Trt 1), C. integerrima×Gliricidia sepium (GS) (Trt 2), Aporosa lindeliyana×LL (Trt 3), A. lindeliyana×GS (Trt 4), Ceiba perntandra×LL (Trt 5), C. perntandra×GS (Trt 6), Artocarpus heterophyllus×LL (Trt 7), A. heterophyllus×GS (Trt 8). The condensed tannin (CT) content of non legumes ranged from 6.2% (Carallia integerrima) to 4.9% (Ceiba perntandra) while the CT of legumes were 1.58% (Leucaena leucocephala) and 0.78% (Gliricidia sepium). Forage mixtures contained more than 14% of crude protein (CP) while the CT content ranged from 2.8% to 4.0% respectively. Differences (pheterophyllus×L. leucocephala (Trt 7) and A. heterophyllus×G. sepium (Trt 8). Highest (p>0.05) NH3-N (ml/200 mg DM) production was observed with the A. heterophyllus×G. sepium (Trt 8) mixture which may be attributed with it's highest CP content. The correlation between IVGP and CT was 0.675 while IVGP and CP was 0.610. In vitro dry matter degradation (IVDMD) was highest in Trt 8 as well. Methane production ranged from 2.57 to 4.79 (ml/200 mg DM) to be synonimous with IVGP. A higher bacteria population (pArtocarpus heterophyllus+G. sepium (Trt 8) and the same trend was observed with the protozoa population as well. The results show that supplementing high tannin non leguminous forages by incremental substitution of legume forage increased gas production parameters, NH3-N, IVDMD and microbial population in the fermentation liquid. Methane production was not significantly affected by the presence of CT or different levels of CP in forage mixtures. Among non legumes, Ceiba

Effects of Tropical High Tannin Non Legume and Low Tannin Legume Browse Mixtures on Fermentation Parameters and Methanogenesis Using Gas Production Technique

Directory of Open Access Journals (Sweden)

T. Seresinhe

2012-10-01

Full Text Available In vitro experiments were conducted to evaluate the suitability of several mixtures of high tanniniferous non legumes with low tanniniferous legumes on in vitro gas production (IVGP, dry matter degradation, Ammonia-N, methane production and microbial population. Eight treatments were examined in a randomized complete block design using four non-legumes and two legumes (Carallia integerrima×Leucaena leucocephala (LL (Trt 1, C. integerrima×Gliricidia sepium (GS (Trt 2, Aporosa lindeliyana×LL (Trt 3, A. lindeliyana×GS (Trt 4, Ceiba perntandra×LL (Trt 5, C. perntandra×GS (Trt 6, Artocarpus heterophyllus×LL (Trt 7, A. heterophyllus×GS (Trt 8. The condensed tannin (CT content of non legumes ranged from 6.2% (Carallia integerrima to 4.9% (Ceiba perntandra while the CT of legumes were 1.58% (Leucaena leucocephala and 0.78% (Gliricidia sepium. Forage mixtures contained more than 14% of crude protein (CP while the CT content ranged from 2.8% to 4.0% respectively. Differences (p0.05 NH3-N (ml/200 mg DM production was observed with the A. heterophyllus×G. sepium (Trt 8 mixture which may be attributed with it’s highest CP content. The correlation between IVGP and CT was 0.675 while IVGP and CP was 0.610. In vitro dry matter degradation (IVDMD was highest in Trt 8 as well. Methane production ranged from 2.57 to 4.79 (ml/200 mg DM to be synonimous with IVGP. A higher bacteria population (p<0.05 was found in C. perntandra×G. sepium (Trt 6 followed by Artocarpus heterophyllus+G. sepium (Trt 8 and the same trend was observed with the protozoa population as well. The results show that supplementing high tannin non leguminous forages by incremental substitution of legume forage increased gas production parameters, NH3-N, IVDMD and microbial population in the fermentation liquid. Methane production was not significantly affected by the presence of CT or different levels of CP in forage mixtures. Among non legumes, Ceiba perntandra and Artocarpus

Carbon respiration and nitrogen dynamics in Corsican pine litter amended with aluminium and tannins

NARCIS (Netherlands)

Kraal, P.; Nierop, K.G.J.; Kaal, J.; Tietema, A.

2009-01-01

We investigated the carbon (C) mineralisation and nitrogen (N) dynamics in litter from a Corsican pine forest in response to individual and combined additions of aluminium (M), condensed tannin (extracted from fresh Corsican pine needles) and hydrolysable tannin (commercial tannic acid). Production

Methods for extraction and characterization of tannins from some acacia species of sudan

International Nuclear Information System (INIS)

Elgailani, I.E.H.; Ishak, C.Y.

2016-01-01

The study is aimed to analyze and compare extraction methods of tannins from three common Acacia species of Sudan. The Acacia species selected were Acacia nilotica, Acacia seyal and Acacia senegal. Bark samples from bulk collections of the three Acacia species were extracted with water, 80% methanol and 70% acetone. Two sets of extraction were made, one by boiling and a second by shaking the samples in the respective solvents for eight hours at room temperature. Although the amount of material extracted by these two procedures did not differ greatly (P > 0.05), 70% acetone was a more efficient solvent than either water or 80% methanol. The tannins of mature fruits extract of Acacia nilotica were identified by using Thin Layer Chromatography (TLC), Ultraviolet and Infrared spectroscopy. Comparisons of absorption spectra and TLC of the reference tannins and some phenolics with that of Acacia nilotica extracts revealed the presence of both condensed and hydrolyzable tannins, since it consists of catechin, tannic and gallic acids. Catechin considered to be the phenolic precursor of condensed tannins. Hydrolysis of Acacia nilotica extract, tannic and gallic acids by butanolic-hydrochloric acid yielded gallic acid which is considered to be a chemical precursor of hydrolyzable tannins. (author)

Methods for Extraction and Charaterization of Tannins from Some Acacia Species of Sudan

Directory of Open Access Journals (Sweden)

Isam Eldin Hussein Elgailani

2016-06-01

Full Text Available The study is aimed to analyze and compare extraction methods of tannins from three common Acacia species of Sudan. The Acacia species selected were Acacia nilotica, Acacia seyal and Acacia senegal. Bark samples from bulk collections of the three Acacia species were extracted with water, 80% methanol and 70% acetone. Two sets of extraction were made, one by boiling and a second by shaking the samples in the respective solvents for eight hours at room temperature. Although the amount of material extracted by these two procedures did not differ greatly (P > 0.05, 70% acetone was a more efficient solvent than either water or 80% methanol. The tannins of mature fruits extract of Acacia nilotica were identified by using Thin Layer Chromatography (TLC, Ultraviolet and Infrared spectroscopy. Comparisons of absorption spectra and TLC of the reference tannins and some phenolics with that of Acacia nilotica extracts revealed the presence of both condensed and hydrolyzable tannins, since it consists of catechin, tannic and gallic acids. Catechin considered to be the phenolic precursor of condensed tannins. Hydrolysis of Acacia nilotica extract, tannic and gallic acids by butanolic-hydrochloric acid yielded gallic acid which is considered to be a chemical precursor of hydrolyzable tannins

The susceptibility of soil enzymes to inhibition by leaf litter tannins is dependent on the tannin chemistry, enzyme class and vegetation history.

Science.gov (United States)

Triebwasser, Daniella J; Tharayil, Nishanth; Preston, Caroline M; Gerard, Patrick D

2012-12-01

By inhibiting soil enzymes, tannins play an important role in soil carbon (C) and nitrogen (N) mineralization. The role of tannin chemistry in this inhibitory process, in conjunction with enzyme classes and isoforms, is less well understood. Here, we compared the inhibition efficiencies of mixed tannins (MTs, mostly limited to angiosperms) and condensed tannins (CTs, produced mostly by gymnosperms) against the potential activity of β-glucosidase (BG), N-acetyl-glucosaminidase (NAG), and peroxidase in two soils that differed in their vegetation histories. Compared with CTs, MTs exhibited 50% more inhibition of almond (Prunus dulcis) BG activity and greater inhibition of the potential NAG activity in the gymnosperm-acclimatized soils. CTs exhibited lower BG inhibition in the angiosperm-acclimated soils, whereas both types of tannins exhibited higher peroxidase inhibition in the angiosperm soils than in gymnosperm soils. At all of the tested tannin concentrations, irrespective of the tannin type and site history, the potential peroxidase activity was inhibited two-fold more than the hydrolase activity and was positively associated with the redox-buffering efficiency of tannins. Our finding that the inhibitory activities and mechanisms of MTs and CTs are dependent on the vegetative history and enzyme class is novel and furthers our understanding of the role of tannins and soil isoenzymes in decomposition. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Contributions to the phytochemical study of Bidens tripartitae herba from Romania. I. Tannins.

Science.gov (United States)

Zagnat, M; Cheptea, Corina; Spac, A F

2013-01-01

To analyze qualitatively and quantitatively tannins in the native plant, collected during the whole vegetation period from different areas of the country, and in its different organs (flower, stem, leaf). For quantitative analysis, the plant product was extracted by repeated maceration (3 days) with 80% methanol. Proanthocyanidins in the extract were quantified by spectrophotometric methods. condensed tannins were present while hydrolyzed tannins were absent. Chromatographic analysis showed that tannins spectrum is similar in all plant organs and in plants collected at different times throughout the vegetation period. The differences are only quantitative. The maximum amount of tannins was found during the flowering stage (10.32%). In terms of tannin content, flowering is the best time to collect. However, collection throughout the whole vegetation period is acceptable.

Effects of Condensed Tannins in Mao ( Muell. Arg. Seed Meal on Rumen Fermentation Characteristics and Nitrogen Utilization in Goats

Directory of Open Access Journals (Sweden)

P. Gunun

2016-08-01

Full Text Available Mao seed is a by-product of the wine and juice industry, which could be used in animal nutrition. The current study was designed to determine the effect of supplementation of mao (Antidesma thwaitesianum Muell. Arg. seed meal (MOSM containing condensed tannins (CT on rumen fermentation, nitrogen (N utilization and microbial protein synthesis in goats. Four crossbred (Thai Native×Anglo Nubian goats with initial body weight (BW 20±2 kg were randomly assigned to a 4×4 Latin square design. The four dietary treatments were MOSM supplementation at 0%, 0.8%, 1.6%, and 2.4% of total dry matter (DM intake, respectively. During the experimental periods, all goats were fed a diet containing roughage to concentrate ratio of 60:40 at 3.0% BW/d and pangola grass hay was used as a roughage source. Results showed that supplementation with MOSM did not affect feed intake, nutrient intakes and apparent nutrient digestibility (p>0.05. In addition, ruminal pH and ammonia nitrogen (NH3-N were not influenced by MOSM supplementation, whilst blood urea nitrogen was decreased quadraticly (p0.05. There were linear decreases in urinary N (p0.05. From the current study, it can be concluded that supplementation of MOSM at 1.6% to 2.4% of total DM intake can be used to modify ruminal fermentation, especially propionate and N utilization in goats, without affecting the nutrient digestibility, microbial populations and microbial protein synthesis.

Tannins and catechin gallate mediate the vasorelaxant effect of Arbutus unedo on the rat isolated aorta.

Science.gov (United States)

Legssyer, Abdelkhaleq; Ziyyat, Abderrahim; Mekh, Hassane; Bnouham, Mohamed; Herrenknecht, Christine; Roumy, Vincent; Fourneau, Christophe; Laurens, Alain; Hoerter, Jacqueline; Fischmeister, Rodolphe

2004-11-01

This study examined the vascular effect of Arbutus leaves (aqueous extract) and described the isolation of several fractions responsible for their vasorelaxant activity. The aqueous extract (AE) of leaves was tested on rat aortic rings precontracted with 0.1 microm noradrenaline. At 10(-2) g/L, AE produced an endothelium dependent relaxation of 66% +/- 5%, (n = 8). The leaves of Arbutus were then extracted successively with different solvents and the methanol extract was the most active. When tannins (primarily condensed tannins) were precipitated from the methanol extract, they showed a strong vasorelaxant activity (87% +/- 4%, n = 5), whereas the elimination of tannins in the methanol extract reduced significantly its vasorelaxant activity (42% +/- 8%, n = 8, p Arbutus is likely to be due to polyphenol compounds, primarily condensed tannins and catechin gallate. Copyright 2004 John Wiley & Sons, Ltd.

Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products

OpenAIRE

Ignacio García-Estévez; Cristina Alcalde-Eon; Víctor Puente; M. Teresa Escribano-Bailón

2017-01-01

Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others) or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins) and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the...

Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products

Directory of Open Access Journals (Sweden)

Ignacio García-Estévez

2017-11-01

Full Text Available Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the effect of the addition of an enological tannin on the color and pigment composition of red wines made from Vitis vinifera L. cv Tempranillo grapes was also studied by high-performance liquid chromatography with diode array detection coupled to mass spectrometry (HPLC-DAD-MS. Results showed that, in model systems, the addition of the enological tannin favored the formation of anthocyanin-derived pigments, such as A-type and B-type vitisins and flavanol-anthocyanin condensation products, provided that the yeast precursors were previously supplied. Moreover, model systems containing the enological tannins were darker and showed higher values of chroma at the end of the study than control ones. The higher formation of these anthocyanin-derived pigments was also observed in the red wines containing the enological tannin. Moreover, these wine also showed lower lightness (L* values and higher chroma (C*ab values than control wines, indicating a higher stabilization of color.

Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products.

Science.gov (United States)

García-Estévez, Ignacio; Alcalde-Eon, Cristina; Puente, Víctor; Escribano-Bailón, M Teresa

2017-11-23

Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others) or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins) and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the effect of the addition of an enological tannin on the color and pigment composition of red wines made from Vitis vinifera L. cv Tempranillo grapes was also studied by high-performance liquid chromatography with diode array detection coupled to mass spectrometry (HPLC-DAD-MS). Results showed that, in model systems, the addition of the enological tannin favored the formation of anthocyanin-derived pigments, such as A-type and B-type vitisins and flavanol-anthocyanin condensation products, provided that the yeast precursors were previously supplied. Moreover, model systems containing the enological tannins were darker and showed higher values of chroma at the end of the study than control ones. The higher formation of these anthocyanin-derived pigments was also observed in the red wines containing the enological tannin. Moreover, these wine also showed lower lightness (L*) values and higher chroma (C* ab ) values than control wines, indicating a higher stabilization of color.

Short- and long-term tannin induced carbon, nitrogen and phosphorus dynamics in Corsican pine litter

NARCIS (Netherlands)

Nierop, K.G.J.; Verstraten, J.M.; Tietema, A.; Westerveld, J.W.; Wartenbergh, P.E.

2006-01-01

Pine litter amended with either tannic acid (TA) or condensed tannins (CTs) was studied to assess the effects on C, N and P mineralization in relation to the fate of tannins by incubation experiments during various time intervals. TA induced a rapid short-term effect resulting in high C respiration

Isolation and Characterization of Proteolytic Ruminal Bacteria from Sheep and Goats Fed the Tannin-Containing Shrub Legume Calliandra calothyrsus

Science.gov (United States)

McSweeney, Christopher S.; Palmer, Brian; Bunch, Rowan; Krause, Denis O.

1999-01-01

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. PMID:10388706

Exploitation of dietary tannins to improve rumen metabolism and ruminant nutrition.

Science.gov (United States)

Patra, Amlan K; Saxena, Jyotisna

2011-01-15

Tannins (hydrolysable and condensed tannin) are polyphenolic polymers of relatively high molecular weight with the capacity to form complexes mainly with proteins due to the presence of a large number of phenolic hydroxyl groups. They are widely distributed in nutritionally important forage trees, shrubs and legumes, cereals and grains, which are considered as anti-nutritional compounds due to their adverse effects on intake and animal performance. However, tannins have been recognised to modulate rumen fermentation favourably such as reducing protein degradation in the rumen, prevention of bloat, inhibition of methanogenesis and increasing conjugated linoleic acid concentrations in ruminant-derived foods. The inclusion of tannins in diets has been shown to improve body weight and wool growth, milk yields and reproductive performance. However, the beneficial effects on rumen modulation and animal performance have not been consistently observed. This review discusses the effects of tannins on nitrogen metabolism in the rumen and intestine, and microbial populations (bacteria, protozoa, fungi and archaea), metabolism of tannins, microbial tolerance mechanisms to tannins, inhibition of methanogenesis, ruminal biohydrogenation processes and performance of animals. The discrepancies of responses of tannins among different studies are attributed to the different chemical structures (degree of polymerisation, procyanidins to propdelphinidins, stereochemistry and C-C bonding) and concentrations of tannins, and type of diets. An establishment of structure-activity relationship would be required to explain differences among studies and obtain consistent beneficial tannin effects. Copyright © 2010 Society of Chemical Industry.

Changes in hematology and serum biochemical profiles in lambs fed sericea lespedeza

Science.gov (United States)

Sericea lespedeza (SL; Lespedeza cuneata) is a legume rich in condensed tannins (CT) that can be grazed or fed to small ruminants for parasite control. Condensed tannins a secondary plant compound in SL may lead to unintended consequences such as changes in production. In our preliminary research, t...

Tannin concentration enhances seed caching by scatter-hoarding rodents: An experiment using artificial ‘seeds’

Science.gov (United States)

Wang, Bo; Chen, Jin

2008-11-01

Tannins are very common among plant seeds but their effects on the fate of seeds, for example, via mediation of the feeding preferences of scatter-hoarding rodents, are poorly understood. In this study, we created a series of artificial 'seeds' that only differed in tannin concentration and the type of tannin, and placed them in a pine forest in the Shangri-La Alpine Botanical Garden, Yunnan Province of China. Two rodent species ( Apodemus latronum and A. chevrieri) showed significant preferences for 'seeds' with different tannin concentrations. A significantly higher proportion of seeds with low tannin concentration were consumed in situ compared with seeds with a higher tannin concentration. Meanwhile, the tannin concentration was significantly positively correlated with the proportion of seeds cached. The different types of tannin (hydrolysable tannin vs condensed tannin) did not differ significantly in their effect on the proportion of seeds eaten in situ vs seeds cached. Tannin concentrations had no significant effect on the distance that cached seeds were carried, which suggests that rodents may respond to different seed traits in deciding whether or not to cache seeds and how far they will transport seeds.

Study of the Gamma Radiation Effect on Tannins Samples

International Nuclear Information System (INIS)

Coto Hernandez, I.; Barroso Solares, S.; Martinez Luzardo, F.; Guzman Martinez, F.; Diaz Rizo, O.; Arado Lopez, J.O.; Santana Romero, J.L.; Baeza Fonte, A.; Rapado Paneque, M.; Garcia, F.

2011-01-01

Vegetable tannins are polyphenolic substances of different chemical mixtures, in correspondence with the characteristics of groups of polyphenols. Taking into consideration its composition, we can find different types of flavonoids, mainly in the so-called condensed tannins. In general, many applications have been explored, including the medical ones, due to their proven biological activity as antiviral, antibacterial and others characteristics derived from their reactions with metal ions and amino acids of the protein components. Therefore it is promising to examine the effects of gamma radiation on the structure of tannin, looking for the possible modification of its biological activity. To this end, samples of tannins are irradiated at different doses (maximum dose 35 kGy) with the use of a Cobalt-60 irradiator. Scanning Electron Microscopy (SEM) permitted to characterize the samples in morphology and composition. The changes were analyzed by using infrared spectroscopy Fourier transform (FT-IR) and High Resolution Liquid Chromatography (HPLC). At the end we discuss the implication of the results for a dosage range above 5 kGy. (Author)

Kinetics of the hydrothermal treatment of tannin for producing carbonaceous microspheres.

Science.gov (United States)

Braghiroli, F L; Fierro, V; Izquierdo, M T; Parmentier, J; Pizzi, A; Celzard, A

2014-01-01

Aqueous solutions of condensed tannins were submitted to hydrothermal carbonization (HTC) in a stainless steel autoclave, and the kinetics of hydrothermal carbon formation was investigated by changing several parameters: amount of tannin (0.5; 1.0; 1.5; 2.0 g in 16 mL of water), HTC temperature (130, 160, 180 and 200°C) and reaction times (from 1 to 720 h). The morphology and the structure of the tannin-based hydrothermal carbons were studied by TEM, krypton adsorption at -196°C and helium pycnometry. These materials presented agglomerated spherical particles, having surface areas ranging from 0.6 to 10.0 m(2) g(-1). The chemical composition of the hydrothermal carbons was found to be constant and independent of reaction time. HTC kinetics of tannin were determined and shown to correspond to first-order reaction. Temperature-dependent measurements led to an activation energy of 91 kJ mol(-1) for hydrothermal conversion of tannin into carbonaceous microspheres separable by centrifugation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preliminary analysis of the relationship between structure and anthelmintic activity of condensed tannins in cattle nematodes

DEFF Research Database (Denmark)

Desrues, Oliver; Enemark, Heidi L.; Mueller-Harvey, I.

2013-01-01

Some plant secondary metabolites as tannins have direct anthelminthic properties and may play a role in the control of nematodes in livestock. However, their great diversity in structural characteristics and different levels of content in plants are responsible for a highly variable response...... in anthelmintic activity, as measured in vitro. The aim of the present study was to assess the relationship between tannin structure and anthelmintic activity using an in vitro assay. We used a series of purified tannins (from 65% to 100% of purity) characterized for their degree of polymerization (m......DP), prodelphinidin/procyanidin (PC/PD) ratio and cis/trans ratio by thiolytic degradation. Tannins diluted in two concentrations in water, epigallocatechin gallate (EGCG), positive (ivermectin) and negative (water) controls were examined by the Larval Feeding Inhibition Assay (LFIA) with first stage larvae (L1...

Extraction and quantification of "condensed tannins" as a measure of plant anti-herbivore defence? Revisiting an old problem.

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Heil, Martin; Baumann, Birgit; Andary, Claude; Linsenmair, K Eduard; McKey, Doyle

2002-11-01

Contents of phenolic compounds in leaf extracts often serve as a measure of plant anti-herbivore defence. This method suffers from the multifunctionality of phenolics and from problems with their colorimetric quantification. Here we present further evidence for the pertinence of these problems. Contents of condensed tannins (CCT) were spectrophotometrically quantified in leaf extracts of 11 closely related mimosoid species, and Spodoptera littoralis caterpillars were reared on artificial diet containing these extracts. The relationship of CCT with caterpillar growth differed considerably among plant species, since both positive and negative correlations were detected. There was, however, a negative correlation of CCT with fungal spore germination, indicating a role of these compounds in resistance to fungi. Detailed knowledge on the structure and biological function of defensive compounds and on the overall composition of leaves is required to estimate a plant's defensive efficacy against a particular group of enemies.

Valorization of solid wastes from chestnut industry processing: Extraction and optimization of polyphenols, tannins and ellagitannins and its potential for adhesives, cosmetic and pharmaceutical industry.

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Aires, Alfredo; Carvalho, Rosa; Saavedra, Maria José

2016-02-01

The aim of the current study was to evaluate the potential of chestnut peels to produce pomaces enhanced with tannins to be used in the formulations of wood adhesives, leather tanning or as natural antioxidants in food, cosmetic and pharmaceutical industry. An analytical procedure was planned as 2 factorial design to analyze the influence of solvent (water, Na2SO3 and NaOH at different concentrations of 1, 2, 4, and 8% in water) and extraction time (30, 60, and 120, 240, 480 and 960min) on extraction yield, pH, Stiasny index, and tannins. HPLC-diode array detector equipped with an ionization mass spectrophotometer was used to assess the polyphenol composition. Our results showed that both extraction properties and phytochemicals were significantly affected (Ptannins identified were the hydrolyzable gallic acid, vescalagin castalagin and ellagic acid, and the condensed epigallocatechin, catechin and epicatechin. The solvent 1% Na2SO3 was more effective to extract the condensed tannins whilst hydrolyzable tannins were extracted efficiently by 1% NaOH. The multivariable analysis and the Pearson's correlation coefficients showed a direct association between Stiasny number and the average levels of condensed tannins. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of yeast strain and some nutritional factors on tannin composition and potential astringency of model wines.

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Rinaldi, Alessandra; Blaiotta, Giuseppe; Aponte, Maria; Moio, Luigi

2016-02-01

Nine Saccharomyces cerevisiae cultures, isolated from different sources, were tested for their ability to reduce tannins reactive towards salivary proteins, and potentially responsible for wine astringency. Strains were preliminary genetically characterized and evaluated for physiological features of technological interest. Laboratory-scale fermentations were performed in three synthetic media: CT) containing enological grape tannin; CTP) CT supplemented with organic nitrogen sources; CTPV) CTP supplemented with vitamins. Adsorption of total tannins, tannins reactive towards salivary proteins, yellow pigments, phenolics having antioxidant activity, and total phenols, characterizing the enological tannin, was determined by spectrophotometric methods after fermentation. The presence of vitamins and peptones in musts greatly influenced the adsorption of tannins reactive towards salivary proteins (4.24 g/L gallic acid equivalent), thus promoting the reduction of the potential astringency of model wines. With reference to the different phenolic classes, yeast strains showed different adsorption abilities. From a technological point of view, the yeast choice proved to be crucial in determining changes in gustative and mouthfeel profile of red wines and may assist winemakers to modulate colour and astringency of wine. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro ovicidal and larvicidal activity of condensed tannins on gastrointestinal nematode infestations in sheep (Ovis aries

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Eidi Yoshihara

2014-12-01

Full Text Available Infestations of gastrointestinal parasitic nematodes in sheep result in significant costs to farmers. These infestations are controlled using synthetic anthelmintic treatments, which can result in the development of anthelmintic resistance in nematodes. The use of plants rich in condensed tannins (CTs is a promising alternative for controlling infestations of harmful parasites in sheep, and could allow reduction of the chemical products used. This study investigated the in vitro effect of CTs from Acacia mearnsii extract (AE on egg hatching and motility of third-stage larvae. Egg-hatching rate was measured after incubation with extracts for 48 h at 27 °C. The egg hatch test was performed with dilutions of 0.09, 0.19, 0.39, 0.78, 1.56, 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. Distilled water was used as the negative control. The corresponding egg hatching inhibition percentages were 22.3, 32.3, 39.2, 49.1, 56.7, 59.0, 62.3, 77.3, 92.7, 98.3, and 100%. The concentration required to inhibit egg hatching in 50% of eggs (LC50 was 2.85 mg mL-1. The inhibition achieved with the negative control was 7.06%. A larval migration inhibition test was carried out after incubation with the extracts for 48 h at 27 oC, with AE and distilled water used in dilutions of 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. The corresponding percentages of migration inhibition were 16.5, 37.0, 56.3, 79.4, 91.8, and 97.1%. The concentration required to inhibit migration of 50% of larvae (LC50 was 12.45 mg mL-1. The inhibition achieved with the negative control was 8.53%. The in vitro ovicidal and larvicidal activity of CTs from AE indicate the anthelmintic effect of AE, suggesting the potential of CT extracts to be used as alternatives for controlling gastrointestinal nematode infestations in small ruminants.

Tannins from Hamamelis virginiana bark extract: characterization and improvement of the antiviral efficacy against influenza A virus and human papillomavirus.

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Linda L Theisen

Full Text Available Antiviral activity has been demonstrated for different tannin-rich plant extracts. Since tannins of different classes and molecular weights are often found together in plant extracts and may differ in their antiviral activity, we have compared the effect against influenza A virus (IAV of Hamamelis virginiana L. bark extract, fractions enriched in tannins of different molecular weights and individual tannins of defined structures, including pseudotannins. We demonstrate antiviral activity of the bark extract against different IAV strains, including the recently emerged H7N9, and show for the first time that a tannin-rich extract inhibits human papillomavirus (HPV type 16 infection. As the best performing antiviral candidate, we identified a highly potent fraction against both IAV and HPV, enriched in high molecular weight condensed tannins by ultrafiltration, a simple, reproducible and easily upscalable method. This ultrafiltration concentrate and the bark extract inhibited early and, to a minor extent, later steps in the IAV life cycle and tannin-dependently inhibited HPV attachment. We observed interesting mechanistic differences between tannin structures: High molecular weight tannin containing extracts and tannic acid (1702 g/mol inhibited both IAV receptor binding and neuraminidase activity. In contrast, low molecular weight compounds (<500 g/mol such as gallic acid, epigallocatechin gallate or hamamelitannin inhibited neuraminidase but not hemagglutination. Average molecular weight of the compounds seemed to positively correlate with receptor binding (but not neuraminidase inhibition. In general, neuraminidase inhibition seemed to contribute little to the antiviral activity. Importantly, antiviral use of the ultrafiltration fraction enriched in high molecular weight condensed tannins and, to a lesser extent, the unfractionated bark extract was preferable over individual isolated compounds. These results are of interest for developing and

In situ analysis and structural elucidation of sainfoin (Onobrychis viciifolia) tannins for high-throughput germplasm screening.

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Gea, An; Stringano, Elisabetta; Brown, Ron H; Mueller-Harvey, Irene

2011-01-26

A rapid thiolytic degradation and cleanup procedure was developed for analyzing tannins directly in chlorophyll-containing sainfoin ( Onobrychis viciifolia ) plants. The technique proved suitable for complex tannin mixtures containing catechin, epicatechin, gallocatechin, and epigallocatechin flavan-3-ol units. The reaction time was standardized at 60 min to minimize the loss of structural information as a result of epimerization and degradation of terminal flavan-3-ol units. The results were evaluated by separate analysis of extractable and unextractable tannins, which accounted for 63.6-113.7% of the in situ plant tannins. It is of note that 70% aqueous acetone extracted tannins with a lower mean degree of polymerization (mDP) than was found for tannins analyzed in situ. Extractable tannins had between 4 and 29 lower mDP values. The method was validated by comparing results from individual and mixed sample sets. The tannin composition of different sainfoin accessions covered a range of mDP values from 16 to 83, procyanidin/prodelphinidin (PC/PD) ratios from 19.2/80.8 to 45.6/54.4, and cis/trans ratios from 74.1/25.9 to 88.0/12.0. This is the first high-throughput screening method that is suitable for analyzing condensed tannin contents and structural composition directly in green plant tissue.

A first step towards identification of tannin-derived black carbon: Conventional pyrolysis (Py–GC–MS) and thermally assisted hydrolysis and methylation (THM–GC–MS) of charred condensed tannins

NARCIS (Netherlands)

Kaal, J.; Nierop, K.G.J.; Kraal, P.; Preston, C.M.

2012-01-01

Tannins account for a significant proportion of plant biomass and are likely to contribute to the residues formed by incomplete biomass combustion (black carbon, BC). Nonetheless, the molecular properties of thermally modified tannins have not been investigated in laboratory charring experiments. We

The role of tannins in conventional and membrane treatment of tannery wastewater.

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Munz, G; De Angelis, D; Gori, R; Mori, G; Casarci, M; Lubello, C

2009-05-30

The role that tannins play in tannery wastewater treatment has been evaluated employing a pilot Membrane Bioreactor (MBR) plant and a full scale Conventional Activated Sludge Process (CASP) plant conducted in parallel. The proposed methodology has established the preliminary use of respirometry to examine the biodegradability of a selection of commercial products (synthetic and natural tannins); the subsequent analysis, by means of spectrophotometric reading and RP-IPC (Reverse-Phase Ion-Pair) liquid chromatography, estimates the concentrations of natural tannins and naphthalenesulfonic tanning agents in the influent and effluent samples. The results show that a consistent percentage of the Total Organic Carbon (TOC) in the effluent of the biological phase of the plants is attributable to the presence of natural and synthetic (Sulfonated Naphthalene-Formaldehyde Condensates, SNFC) tannins (17% and 14% respectively). The titrimetric tests that were aimed at evaluating the levels of inhibition on the nitrifying biomass samples did not allow a direct inhibiting effect to be associated with the concentration levels of the tannin in the effluent. Nonetheless, the reduced specific growth rates of ammonium and nitrite oxidising bacteria imply that a strong environmental pressure is present, if not necessarily due to the concentration of tannins, due to the wastewater as a whole. The differences that have emerged by comparing the two technologies (CASP and MBR), in regards to the role that tannins play in terms of biodegradability, did not appear to be significant.

Total Phenolics, Flavonoids, Tannin Contents and Antioxidant Properties of Pleurotus ostreatus Cultivated on Different Wastes and Sawdust

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Ayşenur Yılmaz

2017-01-01

Full Text Available In this study, the usage possibilities of some agro-industrial wastes such as; peanut wastes, potatoes farm wastes, walnut and orange tree sawdust in Pleurotus ostreatus cultivation were investigated and total phenolic, flavonoid, condensed tannin content and antioxidant properties of these methanolic mushroom extracts were examined. For the determination of the total phenolic contents, the Folin-Ciocalteau procedure was used. The content of total flavonoid present in the methanolic extracts was measured using a spectrophotometric assay. Condensed tannins were determined according to the method by Julkunen-Tıtto. The antioxidant capacity was determined using ferric reducing antioxidant power (FRAP and free radical scavenging activity of DPPH. The highest total phenolic content (2.672 ± 0.003 mg GAE/g was found in mushroom cultivated on walnut sawdust. The highest condensed tannin (1.011 ± 0.088 CE mg/g and ferric reducing antioxidant power (FRAP (12.332 ± 0.017 μmol FeSO4.7H2O/g were observed in the same mushroom extract. The highest total flavonoid and free radical scavenging activity of DPPH were found in extract of mushroom cultivated on potatoes handle. Bioactive properties of P. ostreatus cultivated on walnut tree sawdust were generally exhibited remarkable results.

Attenuated Total Reflection Mid-Infrared (ATR-MIR) Spectroscopy and Chemometrics for the Identification and Classification of Commercial Tannins.

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Ricci, Arianna; Parpinello, Giuseppina P; Olejar, Kenneth J; Kilmartin, Paul A; Versari, Andrea

2015-11-01

Attenuated total reflection Fourier transform infrared (FT-IR) spectroscopy was used to characterize 40 commercial tannins, including condensed and hydrolyzable chemical classes, provided as powder extracts from suppliers. Spectral data were processed to detect typical molecular vibrations of tannins bearing different chemical groups and of varying botanical origin (univariate qualitative analysis). The mid-infrared region between 4000 and 520 cm(-1) was analyzed, with a particular emphasis on the vibrational modes in the fingerprint region (1800-520 cm(-1)), which provide detailed information about skeletal structures and specific substituents. The region 1800-1500 cm(-1) contained signals due to hydrolyzable structures, while bands due to condensed tannins appeared at 1300-900 cm(-1) and exhibited specific hydroxylation patterns useful to elucidate the structure of the flavonoid monomeric units. The spectra were investigated further using principal component analysis for discriminative purposes, to enhance the ability of infrared spectroscopy in the classification and quality control of commercial dried extracts and to enhance their industrial exploitation.

Preliminary analysis of the relationship between structure and anthelmintic activity of condensed tannins in cattle nemaotdes

DEFF Research Database (Denmark)

Desrues, Olivier; Larsen Enemark, Heidi; Mueller-Harvey, Irene

2013-01-01

Some plant secondary metabolites as tannins have direct anthelminthic properties and may play a role in the control of nematodes in livestock. However, their great diversity in structural characteristics and different levels of content in plants are responsible for a highly variable response...... in anthelmintic activity, as measured in vitro. The aim of the present study was to assess the relationship between structure and anthelmintic activity using an in vitro assay. We used a series of purified tannins (from 65% to 100% of purity) characterized for their degree of polymerization (mDP), prodelphinidin....../procyanidin ratio and cis/trans ratio by thiolytic degradation. Tannins diluted in two concentrations in water, epigallocatechin gallate, positive (ivermectin) and negative (water) controls were examined by the Larval Feeding Inhibition Assay (LFIA) with first stage larvae (L1) of the cattle nematode Cooperia...

Application of Moessbauer spectroscopy to the study of tannins inhibition of iron and steel corrosion

Energy Technology Data Exchange (ETDEWEB)

Jaen, Juan A., E-mail: jjaen@ancon.up.ac.pa [Universidad de Panama, CITEN, Depto. de Quimica Fisica (Panama); Obaldia, J. De; Rodriguez, M. V. [Universidad de Panama, Escuela de Quimica, Facultad de Ciencias Naturales, Exactas y Tecnologia (Panama)

2011-11-15

The inhibitory effect of tannins was investigated using, among others, potentiodynamic polarizations and Moessbauer spectroscopy. These techniques confirmed that the nature, pH and concentration of tannic solution are of upmost importance in the inhibitory properties of the solutions. It is observed that at low tannin concentration or pH, both, hydrolizable and condensed tannins, effectively inhibit iron corrosion, due to the redox properties of tannins. At pH Almost-Equal-To 0, Moessbauer spectra of the frozen aqueous solutions of iron(III) with the tannin solutions showed that iron is in the form of a monomeric species [Fe(H{sub 2}O){sub 6}]{sup 3 + }, without coordination with the functional hydroxyl groups of the tannins. The suspended material consisted of amorphous ferric oxide and oxyhydroxides, though with quebracho tannin partly resulted in complex formation and in an iron (II) species from a redox process. Other tannins, such as chestnut hydrolysable tannins, do not complex iron at this low pH. Tannins react at high concentrations or pH (3 and 5) to form insoluble blue-black amorphous complexes of mono-and bis-type tannate complexes, with a relative amount of the bis-ferric tannate generally increasing with pH. Some Fe{sup 2 + } in the form of hydrated polymeric ferrous tannate could be obtained. At pH 7, a partially hydrolyzed ferric tannate complex was also formed. The latter two phases do not provide corrosion protection. Tannin solutions at natural pH react with electrodeposited iron films (approx. 6 {mu}m) to obtain products consisting only on the catecholate mono-complex of ferric tannate. Some aspects of the mechanism of tannins protection against corrosion are discussed.

Characterization of condensed tannins from native legumes of the Brazilian northeastern semi-arid Caracterização dos taninos condensados em leguminosas nativas do semi-árido do nordeste brasileiro

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Patrícia Mendes Guimarães-Beelen

2006-12-01

Full Text Available Despite the possible influence of tannins on the nutritional value of the forages from Caatinga vegetation, there are few studies that evaluated their tannin concentration. This study was conducted to characterize condensed tannins present in the legumes species Mimosa hostilis (Jurema Preta, Mimosa caesalpinifolia (Sabiá and Bauhinia cheilantha (Mororó, at three stages of their phenological cycle. The concentration of soluble tannin (ST, bound tannin (BT and total tannin (TT were determined using the butanol-HCL method; astringency was by the radial diffusion method, and the monomeric composition of purified tannins by a high-performance liquid chromatograph with delphinidin, cyanidin and pelargonidin as standards. Concentration and astringency of purified condensed tannins, as well as their monomeric composition varied between species, and in some cases among phenological cycles. The values observed were always above the limits considered beneficial for ruminal digestion (i.e. 5%. Jurema Preta presented the highest values (30.98% TT and 22% astringency at full growth stage, and Mororó the lowest (10.38% TT and 14% astringency during fructification. Jurema Preta presented a mean relationship prodelfinidin (PD: procyanidin (PC of 97:3, which did not vary during the phenological cycle, showing the high astringent capacity of these tannins. Sabiá presented a relationship of 90:20 during full growth and flowering stages, decreasing to 40:50 at fructification. In Mororó the PD:PC relationship was more equilibrated, around 40:50 during full growth and flowering stages, decreasing to 35:60 During fructification. Propelargonidin was not detected or was present at low concentration in the three species.Apesar da possível influência do tanino sobre o valor nutritivo das forrageiras da Caatinga, poucos são os estudos que avaliam a concentração de taninos nestas plantas. O objetivo do presente estudo foi caracterizar os taninos condensados

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency.

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Ma, Wen; Waffo-Teguo, Pierre; Jourdes, Michael; Li, Hua; Teissedre, Pierre-Louis

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed.

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency.

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Wen Ma

Full Text Available Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs, belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP. However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5 was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed.

Chemical Affinity between Tannin Size and Salivary Protein Binding Abilities: Implications for Wine Astringency

Science.gov (United States)

Ma, Wen; Waffo-Teguo, Pierre; Jourdes, Michael; Li, Hua

2016-01-01

Astringency perception, as an essential parameter for high-quality red wine, is principally elicited by condensed tannins in diversified chemical structures. Condensed tannins, which are also known as proanthocyanidins (PAs), belong to the flavonoid class of polyphenols and are incorporated by multiple flavan-3-ols units according to their degree of polymerization (DP). However, the influence of DP size of PAs on astringency perception remains unclear for decades. This controversy was mainly attributed to the lack of efficient strategies to isolate the PAs in non-galloylated forms and with individual degree size from grape/wine. In the present study, the astringency intensity of purified and identified grape oligomeric tannins (DP ranged from 1 to 5) was firstly explored. A novel non-solid phase strategy was used to rapidly exclude the galloylated PAs from the non-galloylated PAs and fractionate the latter according to their DP size. Then, a series of PAs with individual DP size and galloylation were purified by an approach of preparative hydrophilic interaction chromatography. Furthermore, purified compounds were identified by both normal phase HPLC-FLD and reverse phase UHPLC-ESI-Q-TOF. Finally, the contribution of the astringency perception of the individual purified tannins was examined with a salivary protein binding ability test. The results were observed by HPLC-FLD and quantified by changes in PA concentration remaining in the filtrate. In summary, a new approach without a solid stationary phase was developed to isolate PAs according to their DP size. And a positive relationship between the DP of PAs and salivary protein affinity was revealed. PMID:27518822

Effect of condensed tannins in hulls of faba beans (Vivia faba L.) on the activities of trypsin (EC 2.4.21.4) and chymotrypsin (EC 2.4.21.1) in digesta collected from the small intestine of pigs

NARCIS (Netherlands)

Jansman, A.J.M.; Enting, H.; Verstegen, M.W.A.; Huisman, J.

1994-01-01

The effects of condensed tannins in hulls of faba beans (Vicia faba L.) on the activities of trypsin (EC 3.4.21.4) and chymotrypsin (EC 3.4.21.1) in digesta obtained from the small intestine of pigs were studied. Using four castrated male pigs (mean body weight 83 kg) fitted with both a simple

High forage quality helps maintain resilience to gastrointestinal parasites in sheep and goats

Science.gov (United States)

Condensed tannins (CT) in browse and forage plants can have positive or negative effects on livestock health and performance, depending on the type and concentration of CT present in the diet. Historically, bloating in ruminants was reduced or eliminated when grazing legumes that contained CT. Con...

Anti-parasitic effects of plant secondary metabolites on swine nematodes

DEFF Research Database (Denmark)

Williams, A.R.; Pena-Espinoza, Miguel Angel; Fryganas, Christos

– condensed tannins (CT) and sesquiterpene lactones (SL). Different CT-types were purified from various plant sources to reflect their diversity; SL were purified from forage chicory. These PSM were tested in inhibition assays of worm motility and migratory ability. CT had potent activity against A. suum...

Effect of the addition of different types of oenological commercial tannins on phenolic and sensorial red wine characteristics evolution

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Jordão António M.

2016-01-01

Full Text Available The main objective of this work was to understand the effect of the addition of different commercial types of oenological tannins on red wine phenolic compounds and sensorial characteristics evolution. So, six different commercial oenological tannins obtained from different sources at an average dosage recommended by the manufactures were added to a red wine. During 120 wine aging days several phenolic parameters were analyzed (including several individual phenolic compounds by HPLC and also the sensorial characteristics of the wines. Wines treated with oenological tannins showed higher total phenols and flavonoid phenols and lesser color degradation during the aging time considered. After 120 aging days, wines aged with oenological tannins showed more total and individual anthocyanins and significantly more red color that induced significantly color differences in relation to the untreated wine (especially for the wines treated with condensed tannins. From a sensorial point of view it was also possible to detect a clear differentiation between the wines.

Wood ash treatment, a cost-effective way to deactivate tannins in Acacia cyanophylla Lindl. foliage and to improve digestion by Barbarine sheep

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Abidi, S. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia); Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna (Austria); Nefzaoui, A. [Institut National de la Recherche Agronomique de Tunisie (INRAT), Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)

2005-08-19

Three in vitro experiments and one in vivo experiment were carried out to study the effect of wood ash sources (6 L wood ash solution/kg fresh plant leaves) and levels and treatment duration on the nutritive value of acacia leaves. In Experiment 1, samples of fresh (F), dried (D), or dried and ground (DG) acacia were soaked for 6 h in water or acacia wood ash solution (120 g of wood ash dry matter/L of water). Soaking acacia in water decreased total extractable phenols (TP), total extractable tannins (TT) and extractable condensed tannins (CT). Wood ash treatment led to a further decrease of these phenolic compounds and was highest with DG acacia. Experiment 2 investigated different levels of acacia wood ash (0, 120, 180 and 240 g wood ash dry matter/L of water) and treatment duration (1, 2 and 3 days). The higher the level of wood ash, the lower proportion of TP and CT in acacia was noted. In Experiment 3, two sources of wood ash (i.e., acacia and Aleppo pine) and the same solution of each source of wood ash were used eight times. The two sources of wood ash had similar deactivating effect on TP and CT. The rate of decrease of TP and CT was highest when the same wood ash solution was used four consecutive times and decreased progressively thereafter. In these three experiments, water and wood ash treatment reduced organic matter and crude protein content but substantially increased the neutral detergent fibre (NDFom) content of treated acacia. In the fourth experiment, we treated acacia with acacia wood ash (180 g/L of water for 2 days) and the same solution was used five times. Treated and untreated acacia were air-dried and fed ad libitum to two groups, each of four Barbarine rams together with 300 g of concentrate. Wood ash treatment did not affect intake and OM digestibility of the diet but increased crude protein and NDFom digestibility (P < 0.05). Feeding untreated acacia resulted in negative N balances but with wood ash treatment, N balance was positive

Unlocking resources in savannas: how goats and other mixed feeders overcome the negative effects of tannins

NARCIS (Netherlands)

Mkhize, N.R.

2015-01-01

Abstract

This thesis contributes insights on how condensed tannins might mediate the interactions between woody plants and large herbivores in the African savannas. Current understanding in this regard is still based on data from short-term laboratory experiments, mostly

Vertical stratification of the nutritional value of fruit: macronutrients and condensed tannins.

Science.gov (United States)

Houle, Alain; Conklin-Brittain, Nancy L; Wrangham, Richard W

2014-12-01

Competing successfully for the best feeding sites is an important behavioral strategy but little is known about how feeding sites vary nutritionally within a fruit tree. To answer this question we tested how the nutritional value of a fruit is influenced by its ripeness and its height within the tree crown. A complementary objective was to assess the nutritional value of the midripe fruit, a food item rarely mentioned in the literature despite being exploited on a daily basis by many frugivores. We measured how the dry weight of pulp, water content, and concentration of macronutrients and condensed tannins varied within the tree crowns of 15 fruit species. Collections occurred early in the fruiting cycle, so as to assess the amount of food in the tree before its exploitation by primates. We found that (1) the upper crown produced fruit densities 4.2 times higher, and a fruit crop 4.8 times larger, than the lower crown of the same tree; (2) considering only midripe and ripe stages, upper-crown fruits contained 28.6% more dry pulp, 21.1% more water, and 13.5% more sugars per dry matter than lower-crown fruits of the same tree; (3) midripe fruits contained 80% of the concentrations of sugars of ripe fruits, making them a sweeter food item than one would expect from the intermediate color of their epidermis; (4) cellulose, hemicellulose, proteins, and ash proportionally decreased in concentration while dry pulp and sugars increased during ripening; and (5) ripe fruits were usually rare in the tree (<0.5% of all fruit available) compared to midripe fruits (3-8%). Overall, upper-crown feeding sites produced a higher density and quality of food than lower-crown sites of the same tree. Our data therefore provide a clear nutritional explanation for why tree-feeding frugivores compete for the highest feeding sites. © 2014 Wiley Periodicals, Inc.

Tannin Fingerprinting in Vegetable Tanned Leather by Solid State NMR Spectroscopy and Comparison with Leathers Tanned by Other Processes

OpenAIRE

Jan H. van der Westhuizen; David G. Reid; Melinda J. Duer; Susan L. Bonnet; Frederik H. Romer; Andrew P. Underwood; Nadine D. Senekal

2011-01-01

Solid state 13C-NMR spectra of pure tannin powders from four different sources – mimosa, quebracho, chestnut and tara – are readily distinguishable from each other, both in pure commercial powder form, and in leather which they have been used to tan.  Groups of signals indicative of the source, and type (condensed vs. hydrolyzable) of tannin used in the manufacture are well resolved in the spectra of the finished leathers.  These fingerprints are compared with those arising from leathers tann...

The effects of high-tannin leaf litter from transgenic poplars on microbial communities in microcosm soils.

Directory of Open Access Journals (Sweden)

Richard S. Winder

2013-09-01

Full Text Available The impacts of leaf litter from genetically-modified hybrid poplar accumulating high levels of condensed tannins (proanthocyanidins were examined in soil microcosms consisting of moss growing on sieved soil. Moss preferentially proliferated in microcosms with lower tannin content; DGGE detected increased fungal diversity in microcosms with low-tannin litter. The proportion of cloned rDNA sequences from Actinobacteria decreased with litter addition while Bacteroidetes, Chloroflexi, Cyanobacteria, and α-Proteobacteria significantly increased. β–Proteobacteria were proportionally more numerous at high tannin levels. Tannins had no significant impact on overall diversity of bacterial communities analyzed with various estimators. There was an increased proportion of N-fixing bacteria corresponding to the addition of litter with low tannin levels. The addition of litter increased the proportion of Ascomycota/Basidiomycota. Dothideomycetes, Pucciniomycetes, and Tremellomycetes also increased and Agaricomycetes decreased. Agaricomycetes and Sordariomycetes were significantly more abundant in controls, whereas Pucciniomycetes increased in soil with litter from transformed trees (P = 0.051. Richness estimators and diversity indices revealed no significant difference in the composition of fungal communities; PCoA partitioned the fungal communities into three groups: (i those with higher amounts of added tannin from both transformed and untransformed treatments, (ii those corresponding to soils without litter, and (iii those corresponding to microcosms with litter added from trees transformed only with a β-glucuronidase (GUS control vector. While the litter from transformed poplars had significant effects on soil microbe communities, the observed impacts reflected known impacts on soil processes associated with tannins, and were similar to changes that would be expected from natural variation in tannin levels.

The effects of high-tannin leaf litter from transgenic poplars on microbial communities in microcosm soils.

Science.gov (United States)

Winder, Richard S; Lamarche, Josyanne; Constabel, C Peter; Hamelin, Richard C

2013-01-01

The impacts of leaf litter from genetically modified hybrid poplar accumulating high levels of condensed tannins (proanthocyanidins) were examined in soil microcosms consisting of moss growing on sieved soil. Moss preferentially proliferated in microcosms with lower tannin content; DGGE (denaturing gradient gel electrophoresis) detected increased fungal diversity in microcosms with low-tannin litter. The proportion of cloned rDNA sequences from Actinobacteria decreased with litter addition while Bacteroidetes, Chloroflexi, Cyanobacteria, and α-Proteobacteria significantly increased. β-Proteobacteria were proportionally more numerous at high-tannin levels. Tannins had no significant impact on overall diversity of bacterial communities analyzed with various estimators. There was an increased proportion of N-fixing bacteria corresponding to the addition of litter with low-tannin levels. The addition of litter increased the proportion of Ascomycota/Basidiomycota. Dothideomycetes, Pucciniomycetes, and Tremellomycetes also increased and Agaricomycetes decreased. Agaricomycetes and Sordariomycetes were significantly more abundant in controls, whereas Pucciniomycetes increased in soil with litter from transformed trees (P = 0.051). Richness estimators and diversity indices revealed no significant difference in the composition of fungal communities; PCoA (principal coordinate analyses) partitioned the fungal communities into three groups: (i) those with higher amounts of added tannin from both transformed and untransformed treatments, (ii) those corresponding to soils without litter, and (iii) those corresponding to microcosms with litter added from trees transformed only with a β-glucuronidase control vector. While the litter from transformed poplars had significant effects on soil microbe communities, the observed impacts reflected known impacts on soil processes associated with tannins, and were similar to changes that would be expected from natural variation in

Evaluation of Antioxidant Activity, Total Flavonoids, Tannins and Phenolic Compounds in Psychotria Leaf Extracts

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Anelise Samara Nazari Formagio

2014-11-01

Full Text Available The antioxidant activity of Psychotria carthagenensis, P. leiocarpa, P. capillacea and P. deflexa (Rubiaceae extracts were investigated, and the concentrations of total phenolics, flavonoids, condensed tannins and flavonols were determined. The chemical compositions of the extracts were investigated using the high performance liquid chromatography (HPLC/PAD method. We used 1,1-diphenyl-1-picrylhydrazyl free radical (DPPH, β-Carotene bleaching and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS radical cations to determine antioxidant activity. The ability to scavenge radical was measured in these experiments by the discoloration of the solution. Concentrations of constituents were measured spectrophotometrically. P. carthagenensis and P. capillacea exhibited the highest antioxidant activity, in the DPPH test, β-carotene bleaching and ABTS system. The highest phenolic, flavonoid, condensed tannin and flavonol concentration was found in P. carthagenensis and P. capillacea extracts. HPLC-PDA analysis of P. carthagenensis and P. capillacea revealed hydroxycinnamic acid (p-coumaric acid. This is the first report on the antioxidant properties and constituent analysis of these Psychotria extracts.

Field Spectroscopy in the VNIR-SWIR Region to Discriminate between Mediterranean Native Plants and Exotic-Invasive Shrubs Based on Leaf Tannin Content

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Jan Rudolf Karl Lehmann

2015-01-01

Full Text Available The invasive shrub, Acacia longifolia, native to southeastern Australia, has a negative impact on vegetation and ecosystem functioning in Portuguese dune ecosystems. In order to spectrally discriminate A. longifolia from other non-native and native species, we developed a classification model based on leaf reflectance spectra (350–2500 nm and condensed leaf tannin content. High variation of leaf tannin content is common for Mediterranean shrub and tree species, in particular between N-fixing and non-N-fixing species, as well as within the genus, Acacia. However, variation in leaf tannin content has not been studied in coastal dune ecosystems in southwest Portugal. We hypothesized that condensed tannin concentration varies significantly across species, further allowing for distinguishing invasive, nitrogen-fixing A. longifolia from other vegetation based on leaf spectral reflectance data. Spectral field measurements were carried out using an ASD FieldSpec FR spectroradiometer attached to an ASD leaf clip in order to collect 750 in situ leaf reflectance spectra of seven frequent plant species at three study sites in southwest Portugal. We applied partial least squares (PLS regression to predict the obtained leaf reflectance spectra of A. longifolia individuals to their corresponding tannin concentration. A. longifolia had the lowest tannin concentration of all investigated species. Four wavelength regions (675–710 nm, 1060–1170 nm, 1360–1450 nm and 1630–1740 nm were identified as being highly correlated with tannin concentration. A spectra-based classification model of the different plant species was calculated using a principal component analysis-linear discriminant analysis (PCA-LDA. The best prediction of A. longifolia was achieved by using wavelength regions between 1360–1450 nm and 1630–1740 nm, resulting in a user’s accuracy of 98.9%. In comparison, selecting the entire wavelength range, the best user accuracy only reached 86

Saliva tannin interactions.

Science.gov (United States)

Prinz, J F; Lucas, P W

2000-11-01

Many plant foods contain tannins, compounds that bind proteins, such as mammalian enzymes. Although described as tasteless, tannins can be detected orally by their astringency. However, the actual mechanism of oral detection and the effect of tannins on mastication and swallowing have been little investigated. Here, we show from in vitro tests that tannic acid, a common standard in tests used to detect tannins, significantly reduces the lubricating qualities of human saliva both by decreasing its viscosity and increasing friction, both factors lending support to the notion that astringency is a tactile phenomenon. From the literature, it is clear that this effect depends on the presence of salivary proline-rich proteins (PRP). In a mammalian context, ingestion of tannin-rich foods in a species with salivary PRP will be signalled by interference with bolus formation during mastication while the increase in friction may also be detectable and lead to increased tooth wear if the signal is ignored. In a human context, cross-cultural preferences for tannin-rich beverages such as tea, coffee and red wine at the end of meals may be explained by reduction in adhesion of food particles to the oral mucosa allowing their rapid oral clearance.

Nutraceutic effect of free condensed tannins of Lysiloma acapulcensis (Kunth) benth on parasite infection and performance of Pelibuey sheep.

Science.gov (United States)

García-Hernández, Cesar; Arece-García, Javier; Rojo-Rubio, Rolando; Mendoza-Martínez, German David; Albarrán-Portillo, Benito; Vázquez-Armijo, José Fernando; Avendaño-Reyes, Leonel; Olmedo-Juárez, Agustín; Marie-Magdeleine, Carine; López-Leyva, Yoel

2017-01-01

Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5 mg of FCT kg -1 of body weight (BW); sterile water (control); and ivermectine (0.22 mg kg -1 of BW) as chemical group. The data were processed through repeated measurement analysis. Even though the three FCT doses decreased (P < 0.05) the FEC, the highest reduction was obtained with 37.5 mg kg -1 of BW. No differences were observed in PCV and OMC. Higher ADG (P < 0.05) was observed with 37.5 mg kg -1 of BW of FCT. The count of adult nematodes (females and males) in the higher dose of FCT was similar to chemical treatment. Dose of 37.5 mg kg -1 of BW decreased the parasite infection and improved the lamb performance. Therefore, this dose could be used as a nutraceutic product in sheep production.

Salivary Amylase Induction by Tannin-Enriched Diets as a Possible Countermeasure Against Tannins

OpenAIRE

da Costa, G.; Lamy, E.; Capela e Silva, Fernando; Andersen, J.; Sales Baptista, E.; Coelho, A.V.

2008-01-01

Tannins are characterized by protein-binding affinity. They have astringent/bitter properties that act as deterrents, affecting diet selection. Two groups of salivary proteins, proline-rich proteins and histatins, are effective precipitators of tannin, decreasing levels of available tannins. The possibility of other salivary proteins having a co-adjuvant role on host defense mechanisms against tannins is unknown. In this work, we characterized and compared the protein profile of mice whole sa...

New insight into the unresolved HPLC broad peak of Cabernet Sauvignon grape seed polymeric tannins by combining CPC and Q-ToF approaches.

Science.gov (United States)

Ma, Wen; Waffo-Téguo, Pierre; Alessandra Paissoni, Maria; Jourdes, Michäel; Teissedre, Pierre-Louis

2018-05-30

Polymeric tannins from grapes have always been reported as an unresolved broad peak in HPLC chromatograms, and this has severely limited their identification to date. This study aimed to disassemble this broad peak and explore the polymeric tannin molecules inside. By applying centrifugal partition chromatography (CPC), an efficient separation approach was developed to split the broad peak of grape seed tannins into fractions. Then, the fractions were analyzed by Q-ToF (quadrupole time-of-flight mass spectrometry) to determine the corresponding structures of the tannins. The results suggest that grape seed polymeric tannins were eluted consecutively according to their degree of polymerization (DP). Condensed tannins identified in wine grape seed have a range of DP and degree of galloylation (DG) up to 20 and 11, respectively. The molecular mass of the largest molecule detected was 6067. To our knowledge, this is the first report to offer an insight into the broad peak of polymeric tannins found with HPLC and to characterize the tannins with a DP up to 20 as shown by HRMS and MS/MS data. Copyright © 2018 Elsevier Ltd. All rights reserved.

Attenuation properties and percentage depth dose of tannin-based Rhizophora spp. particleboard phantoms using computed tomography (CT) and treatment planning system (TPS) at high energy x-ray beams

Energy Technology Data Exchange (ETDEWEB)

Yusof, M. F. Mohd, E-mail: mfahmi@usm.my [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); School of Health Sciences, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan (Malaysia); Abdullah, R. [School of Health Sciences, Universiti Sains Malaysia, 16150 Kota Bharu, Kelantan (Malaysia); Tajuddin, A. A. [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Kepala Batas, Penang (Malaysia); Hashim, R. [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, S. [Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia)

2016-01-22

A set of tannin-based Rhizophora spp. particleboard phantoms with dimension of 30 cm x 30 cm was fabricated at target density of 1.0 g/cm{sup 3}. The mass attenuation coefficient of the phantom was measured using {sup 60}Co gamma source. The phantoms were scanned using Computed Tomography (CT) scanner and the percentage depth dose (PDD) of the phantom was calculated using treatment planning system (TPS) at 6 MV and 10 MV x-ray and compared to that in solid water phantoms. The result showed that the mass attenuation coefficient of tannin-based Rhizohora spp. phantoms was near to the value of water with χ{sup 2} value of 1.2. The measured PDD also showed good agreement with solid water phantom at both 6 MV and 10 MV x-ray with percentage deviation below 8% at depth beyond the maximum dose, Z{sub max}.

Effet de l'addition des tannins de châtaigniers sur la rétention azotée et la digestibilité chez les ruminants ingérant des produits herbagers

Directory of Open Access Journals (Sweden)

Kriaa, S.

1999-01-01

Full Text Available The Influence of the Addition of Extract of Chestnut Tannin on the Nitrogen Balance and the Digestibility of Fresh Grass in Ruminant. The use of chestnut tannin (CT (hydrolysable Tannins, added at a low concentration (4 g CT/100 g of total nitrogen (TN = 0, 8 g cT/kg of DM distribute to a grass forage for growing sheep, improves the N retention (P <0, 01. The improvement of N retention is explained by the decrease of nitrogen in the urine, indicating a better use of absorbed nitrogen. Moreover, the addition at these low concentrations of CT to fresh grass does not alter neither the digestibility of its constituents (OM, TN, ADF nor the rate of ingestion.

Anthocyanins influence tannin-cell wall interactions.

Science.gov (United States)

Bautista-Ortín, Ana Belén; Martínez-Hernández, Alejandro; Ruiz-García, Yolanda; Gil-Muñoz, Rocío; Gómez-Plaza, Encarna

2016-09-01

The rate of tannin extraction was studied in a vinification of red grapes and the results compared with another vinification made with white grapes fermented as for typical red wine, in the presence of skins and seeds. Even though the grapes presented a quite similar skin and seed tannin content, the differences in tannin concentration between both vinifications was very large, despite the fact that the only apparent difference between the phenolic composition of both wines was the anthocyanin content. This suggests that anthocyanins play an important role in tannin extractability, perhaps because they affect the extent of the tannin-cell wall interaction, a factor that largely controls the resulting quantity of tannins in wines. To confirm this observation, the effect of anthocyanins on the tannin extractability from grape seeds and skin and on the interaction between tannins and grape cell walls suspended in model solutions were studied. The results indicated that anthocyanins favored skin and seed tannin extraction and that there is a competition for the adsorption sites between anthocyanins and tannins that increases the tannin content when anthocyanins are present. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tannins and Tannin-Related Derivatives Enhance the (Pseudo-)Halogenating Activity of Lactoperoxidase.

Science.gov (United States)

Gau, Jana; Prévost, Martine; Van Antwerpen, Pierre; Sarosi, Menyhárt-Botond; Rodewald, Steffen; Arnhold, Jürgen; Flemmig, Jörg

2017-05-26

Several hydrolyzable tannins, proanthocyanidins, tannin derivatives, and a tannin-rich plant extract of tormentil rhizome were tested for their potential to regenerate the (pseudo-)halogenating activity, i.e., the oxidation of SCN - to hypothiocyanite - OSCN, of lactoperoxidase (LPO) after hydrogen peroxide-mediated enzyme inactivation. Measurements were performed using 5-thio-2-nitrobenzoic acid in the presence of tannins and related substances in order to determine kinetic parameters and to trace the LPO-mediated - OSCN formation. The results were combined with docking studies and molecular orbital analysis. The - OSCN-regenerating effect of tannin derivatives relates well with their binding properties toward LPO as well as their occupied molecular orbitals. Especially simple compounds like ellagic acid or methyl gallate and the complex plant extract were found as potent enzyme-regenerating compounds. As the (pseudo-)halogenating activity of LPO contributes to the maintenance of oral bacterial homeostasis, the results provide new insights into the antibacterial mode of action of tannins and related compounds. Furthermore, chemical properties of the tested compounds that are important for efficient enzyme-substrate interaction and regeneration of the - OSCN formation by LPO were identified.

Tannins from Acacia mearnsii De Wild. Bark: Tannin Determination and Biological Activities.

Science.gov (United States)

Ogawa, Sosuke; Yazaki, Yoshikazu

2018-04-05

The bark of Acacia mearnsii De Wild. (black wattle) contains significant amounts of water-soluble components acalled "wattle tannin". Following the discovery of its strong antioxidant activity, a wattle tannin dietary supplement has been developed and as part of developing new dietary supplements, a literature search was conducted using the SciFinder data base for " Acacia species and their biological activities". An analysis of the references found indicated that the name of Acacia nilotica had been changed to Vachellia nilotica , even though the name of the genus Acacia originated from its original name. This review briefly describes why and how the name of A. nilotica changed. Tannin has been analyzed using the Stiasny method when the tannin is used to make adhesives and the hide-powder method is used when the tannin is to be used for leather tanning. A simple UV method is also able to be used to estimate the values for both adhesives and leather tanning applications. The tannin content in bark can also be estimated using NIR and NMR. Tannin content estimations using pyrolysis/GC, electrospray mass spectrometry and quantitative 31 P-NMR analyses have also been described. Tannins consists mostly of polyflavanoids and all the compounds isolated have been updated. Antioxidant activities of the tannin relating to anti-tumor properties, the viability of human neuroblastoma SH-SY5Y cells and also anti-hypertensive effects have been studied. The antioxidant activity of proanthocyanidins was found to be higher than that of flavan-3-ol monomers. A total of fourteen papers and two patents reported the antimicrobial activities of wattle tannin. Bacteria were more susceptible to the tannins than the fungal strains tested. Several bacteria were inhibited by the extract from A. mearnsii bark. The growth inhibition mechanisms of E. coli were investigated. An interaction between extracts from A. mearnsii bark and antibiotics has also been studied. The extracts from A. mearnsii

Toward the optical tongue: flow-through sensing of tannin-protein interactions based on FTIR spectroscopy.

Science.gov (United States)

Edelmann, Andrea; Lendl, Bernhard

2002-12-11

The interaction of polyphenols (tannins) with proline-rich proteins (gelatin) has been studied using an automated flow injection system with Fourier transform infrared spectroscopic detection to gain insight into chemical aspects related to astringency. In the perception of astringency, a major taste property in red wines and other beverages such as beer, tea, or fruit juices, an interaction between proline-rich salivary proteins and tannins present in the sample takes place. To study this interaction, agarose beads carrying gelatin (a proline-rich protein) were placed in the IR flow cell in such a way that the beads were probed by the IR beam. Using an automated flow system, we injected samples in a carrier stream and flushed over the proteins in a highly reproducible manner. Simultaneously, any retardation due to tannin-protein interactions taking place inside the flow cell was monitored by infrared spectroscopy. Tannins of different sources (grapes, wooden barrels, formulations used in wine making) were investigated, and their flow-through behavior was characterized. Significant differences in their affinity toward gelatin could be observed. Furthermore, because of small but characteristic differences in the IR spectrum, it is possible to distinguish condensed from hydrolyzable tannins. Nonastringent substances such as alcohols, sugars, and acids did not show retention on gelatin. The selectivity of the flow-through sensor was also demonstrated on the example of red and white wine. In contrast to white wine, where no interaction could be observed, in red wine a major interaction of the red wine tannins was found.

Condensed tannins reduce browsing and increase grazing time of free-ranging goats in semi-arid savannas

CSIR Research Space (South Africa)

Mkhize, NR

2015-08-01

Full Text Available Tannin concentrations fluctuate spatially and temporally within and among plant species, with con-sequences for forage quality of herbivores. The extent to which these fluctuations influence foraging activities of goats is not fully understood...

First C/sub 4/-functionalisation of condensed tannins. Phlobatannins as prototype of a new class of C-ring isomerised oligomers. Die eerste C/sub 4/-funksionalisering van gekondenseerde tanniene. Flobatanniene as prototipe van 'n nuwe klas van C-ring geisomeriseerde oligomere

Energy Technology Data Exchange (ETDEWEB)

Steenkamp, J A

1986-06-01

This thesis comprises besides the characterisation of new oligomeric flavenoids from the core wood of the indigeneous Colophosphermum mopane, an investigation into the C/sub 4/-functionalisation of flavan-3-ol analogues. The first peltogynoid biflavenoid and prototypes of a new series C-ring isomerised condensed tannins, namely the phlobatannins, were isolated. Besides /sup 1/H- nmr-parameters for structure analysis, the natural phlobatannins were characterised and the unique ring isomerisation was investigated.

Tannins from Acacia mearnsii De Wild. Bark: Tannin Determination and Biological Activities

Directory of Open Access Journals (Sweden)

Sosuke Ogawa

2018-04-01

Full Text Available The bark of Acacia mearnsii De Wild. (black wattle contains significant amounts of water-soluble components acalled “wattle tannin”. Following the discovery of its strong antioxidant activity, a wattle tannin dietary supplement has been developed and as part of developing new dietary supplements, a literature search was conducted using the SciFinder data base for “Acacia species and their biological activities”. An analysis of the references found indicated that the name of Acacia nilotica had been changed to Vachellia nilotica, even though the name of the genus Acacia originated from its original name. This review briefly describes why and how the name of A. nilotica changed. Tannin has been analyzed using the Stiasny method when the tannin is used to make adhesives and the hide-powder method is used when the tannin is to be used for leather tanning. A simple UV method is also able to be used to estimate the values for both adhesives and leather tanning applications. The tannin content in bark can also be estimated using NIR and NMR. Tannin content estimations using pyrolysis/GC, electrospray mass spectrometry and quantitative 31P-NMR analyses have also been described. Tannins consists mostly of polyflavanoids and all the compounds isolated have been updated. Antioxidant activities of the tannin relating to anti-tumor properties, the viability of human neuroblastoma SH-SY5Y cells and also anti-hypertensive effects have been studied. The antioxidant activity of proanthocyanidins was found to be higher than that of flavan-3-ol monomers. A total of fourteen papers and two patents reported the antimicrobial activities of wattle tannin. Bacteria were more susceptible to the tannins than the fungal strains tested. Several bacteria were inhibited by the extract from A. mearnsii bark. The growth inhibition mechanisms of E. coli were investigated. An interaction between extracts from A. mearnsii bark and antibiotics has also been studied. The

Condensed tannins reduce browsing and increase grazing time of free-ranging goats in semi-arid savannas

NARCIS (Netherlands)

Mkhize, N.R.; Heitkönig, I.M.A.; Scogings, P.F.; Dziba, L.E.; Prins, H.H.T.; Boer, de W.F.

2015-01-01

Tannin concentrations fluctuate spatially and temporally within and among plant species, with consequences for forage quality of herbivores. The extent to which these fluctuations influence foraging activities of goats is not fully understood. While accounting for the effects of the time of the day

Adsorption recovery of thorium(IV) by Myrica rubra tannin and larch tannin immobilized onto collagen fibres

International Nuclear Information System (INIS)

Xuepin Liao; Li Li; Bi Shi

2004-01-01

Novel adsorbents which can concentrate Th(IV) in aqueous solution were prepared by immobilizing Myrica rubra tannin and larch tannin onto collagen fibre matrices. The adsorption capacities of the immobilized tannins to Th(IV) are related to temperature and pH value of the adsorption process. For example, when the initial concentration of Th(IV) was 116.0 mg x l -1 and the immobilized tannin was 100 mg, the adsorption capacities of immobilized Myrica rubra tannin and larch tannin were 55.98 mg Th(IV) x g -1 and 13.19 mg Th(IV) x g -1 , respectively at 303 K, and 73.67 mg Th(IV) x g -1 and 18.19 mg Th(IV) x g -1 at 323 K. It was also found that the higher adsorption capacity was obtained at higher pH value. The adsorption equilibrium data of the immobilized tannins for Th(IV) can be well fitted by the Langmuir model and the mechanism of the adsorption was found to be a chemical adsorption. In general, the adsorption capacity of immobilized Myrica rubra tannin to Th(IV) is significantly higher than that of immobilized larch tannin, probably due to the fact that the B ring of Myrica rubra tannin has a pyrogallol structure which has higher reaction activity with metal ions. The breakthrough point of the adsorption column of immobilized Myrica rubra tannin was at 33 bed volumes for the experimental system. The mass transfer coefficient of adsorption column determined by Adams-Bohart equation was 1.61 x 10 -4 l x mg -1 x min -1 . The adsorption column can be easily regenerated by 0.1 mol x l -1 HNO 3 solution, showing outstanding ability of concentrating Th(IV). (author)

The use of polyethylene glycol to reduce the anti-nutritional effects of tannins in Cistus ladanifer L.

Directory of Open Access Journals (Sweden)

Maria Teresa P. Dentinho

2018-05-01

Full Text Available Aim of study: To evaluate the impact of Cistus ladanifer L. (rockrose tannins on ruminal degradability and fermentation characteristics and the use of polyethylene glycol (PEG, as feed additive, to mitigate the anti-nutritional effects of rockrose tannins. Material and methods: Aerial parts of rockrose plants were harvested in March, freeze dried and divided in 4 subsamples which were treated with 0, 25, 50 and 75 g of PEG/kg of dry matter (DM. The mixtures were analysed for chemical composition including total phenolics, total tannins and condensed tannins. In situ rumen organic matter (OM and N rumen degradability was evaluated using three rumen-cannulated rams and ruminal fermentation pattern (volatile fatty acids (VFA, gas production was evaluated in vitro using a Rumen Simulation Technique (RUSITEC apparatus. Main results: In situ experiment indicated that the effective degradability of the OM and N increased linearly (p<0.05 with PEG inclusion due to an increase of the degradation rate (p<0.05. RUSITEC data indicated that substrate disappearance and gas and VFA production increased linearly (p<0.05 with PEG inclusion. Research highlights: Inclusion of PEG to C. ladanifer feed was effective to prevent the anti-nutritive effects of tannins. Thus, the use of PEG as feed additive can promote a better utilization of this shrub by ruminants.

Quantification of tannins and related polyphenols in commercial products of tormentil (Potentilla tormentilla).

Science.gov (United States)

Fecka, Izabela; Kucharska, Alicja Zofia; Kowalczyk, Adam

2015-01-01

Potentilla tormentilla has many biological and pharmacological properties and can be used as an ingredient of some herbal medicines or beverages. The aim of this study was to evaluate the content of individual polyphenols, especially condensed and hydrolysable tannins in commercially available tormentil rhizomes and tinctures using chromatographic methods. A quantitative analysis (HPLC-PDA) was preceded by qualitative studies (UPLC-qTOF-MS/MS) and the isolation (CC) of the major tannin compounds. The tested plant material is characterised by a high content of tannins and related polyphenols, i.e. in rhizomes even at the level above 20% and in tinctures above 2%. The main components of tormentil rhizomes are procyanidin B3 (mean ~ 3.6%), procyanidin C2 (mean ~ 2.8%), agrimoniin (mean ~ 2.5%), 3-O-galloylquinic acid (mean ~ 1.7%), catechin (mean ~ 1.6%), other flavan-3-ol oligomers (mean ~ 0.5-1.1) and laevigatins (mean ~ 0.2-0.6%). Free ellagic acid and glycosides of ellagic and methylellagic acids are secondary components. Underground parts of tormentil are a source of oligomeric proanthocyanidins and ellagitannins, but in smaller quantity of gallotannins. Monogalloylquinic acids are new identified compounds, which had not been described in Potentilla tormentilla before we started our research. In the analysed tormentil tinctures agrimoniin concentration is lower in relation to other tannins. Copyright © 2015 John Wiley & Sons, Ltd.

Extracción y evaluación de taninos condensados a partir de la corteza de once especies maderables de Costa Rica Extraction and evaluation of condensed tannins from bark of eleven species of trees from Costa Rica

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Jorge Aguilar López

2012-12-01

Full Text Available La naturaleza química de los taninos condensados los convierte en una fuente natural de compuestos orgáni- cos, con una aplicación potencialmente amplia para usos medicinales e industriales. La extracción y análisis de este tipo de metabolitos a partir de la flora de diversas regiones del planeta ha sido el objetivo del estudio de diversos grupos de trabajo, y en este caso se ha querido hacer un aporte al estado del conocimiento actual, realizando un estudio sobre la natu- raleza y la cantidad del tanino condensado que se puede extraer de la corteza de 11 especies arbóreas presentes en Costa Rica: guanacaste (Enterolobium cyclocarpum, alcornoque (Licania arborea, jobo (Spondias mom- bin, pochote (Pachira quinata, níspero (Manilkara chicle, almendro (Andira inermis, roble (Tabebuia rosea, cedro (Cedrela odorata, cenízaro (Samanea saman, pino (Pinus caribaea y ciprés (Cupressus lusitanica. Las muestras de corteza fueron preparadas, secadas y extraídas con etanol. Se analizaron los extractos etanóli- cos para determinar el contenido de taninos condensa- dos a través del número de Stiasny, y se caracterizaron mediante espectroscopía infrarroja (FT-IR. Las especies con mayor proporción de material extraído fueron guanacaste (9.5841% m/m, pochote (15.0066% m/m, pino (19.3400% m/m y ciprés (10.5300% m/m, mientras que los extractos con una mayor proporción de taninos condensados correspondieron a alcornoque (61.9% m/m, jobo (66.1% m/m, pochote (72.8% m/m, níspero (50.5% m/m, cedro (72.7% m/m y pino (70.7% m/m.The chemical nature of condensed tannins offers a natural source of such organic compounds, with potential application to medicinal and industrial uses. The extraction and analysis of this type of metabo- lites from plants of many regions of the world have been the objective of researching groups. In this case, it is desired to contribute to present knowledge, establishing the nature and amounts of condensed tannins extracted

Quantification of the levels of tannins and total phenols and evaluation of the antioxidant activity of fruits of pepper tree

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Natália Ribeiro Bernardes

2011-12-01

Full Text Available The fruits of pepper tree (Schinus terebinthifolius Raddi are widely used in the world cooking and its consumption has been encouraged since the late 80’s due to the presence of phenolic substances. Therefore, this study quantified the levels of tannins and total phenols in the fruits of pepper tree, aiming at establishing a possible correlation between these substances and their antioxidant activity. Phenolic compounds were extracted with acetone: water (7:3, and quantified by spectrophotometry. The antioxidant activity was measured by DPPH method. The results showed low levels of condensed tannins and total phenols in the peel of the fruit, not being detected hydrolysable tannins in them. Nevertheless, the methanolic extract showed high antioxidant potential, which indicates the absence of a correlation between antioxidant activity and the levels of phenolic compounds in these fruits.

Effects of different fresh-cut forages and their hays on feed intake, digestibility, heat production, and ruminal methane emission by Boer x Spanish goats

Science.gov (United States)

Twenty-four yearling Boer (87.5%) × Spanish wethers (32.5 ± 0.36 kg body weight) were used in a 32-day experiment to assess effects of frequency of feeding condensed tannin (CT)-containing Sericea lespedeza (SL; Lespedeza cuneata) on ruminal methane emission. Fresh SL (15.3% CT) was fed at 1.3 time...

Tannins in tropical woods

Energy Technology Data Exchange (ETDEWEB)

Doat, J

1978-01-01

A preliminary study was made of the chemistry of pyrogallol- and catecholtannins, their general properties and methods of extraction and determination. Three methods of estimation - Lowenthal, powdered hide and spectrophotometry - were compared using two control solutions, four samples of wood and one of bark. Using the empirical powdered hide method, tannins of both types were estimated in wood and bark of various tropical species (some separately and some as a mixture), Moroccan oaks (Quercus suber and Q. ilex), and European oak 9Q. petraea). Further tests were made on the wood and bark of the two mangrove species, Rhizophora mangle and R. racemosa, by subjecting them to successive extraction with a range of solvents. None of the woods tested had as much as the 10% of tannins considered necessary in economic sources. The bark of the two mangroves, of Eucalyptus urophylla and of Prosopis africana had tannin contents over 10% and the latter two species had very favorable tannin/non-tannin ratios. All the tropical species, with the probable exception of E. urophylla, had only catecholtannins. Only the oaks and E. urophylla bark gave positive results when tested for gallotannins.

Effects of graded levels of tannin-containing tropical tree leaves on in vitro rumen fermentation, total protozoa and methane production.

Science.gov (United States)

Bhatta, R; Saravanan, M; Baruah, L; Prasad, C S

2015-03-01

This study was carried out to determine the effect of graded levels of tannin-containing tropical tree leaves, Autocarpus integrifolis, Azardirachta indica and Ficus bengalensis, on the in vitro rumen fermentation pattern, total protozoa and methane suppression in order to establish the optimum dose of these leaves for inclusion in the ruminant diets. The air-dried and ground samples of Au. integrifolis, Az. indica and Ficus bengalensis were subjected to in vitro incubation using 30 ml buffered rumen fluid at 0, 2.5, 5.0, 10.0, 15.0, 20.0, 25.0 and 30.0% (dry matter refers to moisture-free basis) of a total mixed ration (TMR: refers to mixture of roughage and concentrate containing cereals and oil cakes) devoid of tannin. The TMR for the experimental incubation was prepared by mixing 40 parts of ground Elusine coracana straw as roughage source with 60 parts of concentrate mixture. The leaves contained an average 130 g kg(-1) CP with 7·0 MJ of ME kg(-1) DM. The average neutral detergent fibre (NDF) content was content also showed similar trend. However, condensed tannin (CT) was highest in F. bengalensis (260) followed by Au. integrifolis (186) and Az. indica (138). There was significant (P 5.0%) reduced TVFA concentration. Protozoa (cells per mL) were similar at all levels of inclusion with Au. integrifolis, but reduced in case of F. bengalensis and Az. indica. As the level of tannin increased in the incubation medium, there was a linear reduction in methane concentration. Highest methane reduction (%) was recorded in incubations supplemented with Az. indica (61.5) followed by F. bengalensis (46.8) and Au. integrifolis (30.3). It was established from this study that tropical leaves of F. bengalensis, Au. integrifolis and Az. indica suppress methanogenesis. Ficus bengalensis, Au. integrifolis and Az. indica leaves are of interest in the enteric methane ameliorative strategies. Total mixed ration containing 10-15% ground F. bengalensis or Au. integrifolis or Az

Colloidal stability of tannins: astringency, wine tasting and beyond

Science.gov (United States)

Zanchi, D.; Poulain, C.; Konarev, P.; Tribet, C.; Svergun, D. I.

2008-12-01

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for the visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of β-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency.

Colloidal stability of tannins: astringency, wine tasting and beyond

Energy Technology Data Exchange (ETDEWEB)

Zanchi, D; Poulain, C [Laboratoire de Physique Theorique et Hautes Energies, 4 Place Jussieu, BP 126, F-75252 Paris Cedex 05 (France); Konarev, P; Svergun, D I [European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, D-22603 Hamburg (Germany); Tribet, C [Physico-Chimie des Polymeres et Milieux Disperses, CNRS UMR 7615, ESPCI, 10 rue Vauquelin, F-75231 Paris Cedex 05 (France)], E-mail: drazen@lpthe.jussieu.fr

2008-12-10

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for the visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of {beta}-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency.

Colloidal stability of tannins: astringency, wine tasting and beyond

International Nuclear Information System (INIS)

Zanchi, D; Poulain, C; Konarev, P; Svergun, D I; Tribet, C

2008-01-01

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for the visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of β-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency.

Colloidal stability of tannins: astringency, wine tasting and beyond

OpenAIRE

Zanchi, D.; Poulain, C.; Konarev, P.; Tribet, C.; Svergun, D. I.

2008-01-01

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is cons...

Dietary effects of faba-bean (Vicia faba L.) tannins on the morphology and function of the small-intestinal mucosa of weaned pigs

NARCIS (Netherlands)

Leeuwen, P. van; Jansman, A.J.M.; Wiebenga, J.; Koninkx, J.F.J.G.; Mouwen, J.M.V.M.

1995-01-01

The objective of the present study was to evaluate effects of condensed tannins in faba beans (Vicia faba L.) on morphological and functional variables of the small-intestinal mucosa of piglets. In an experiment with young piglets (8-17 kg body weight), fed on either a control diet or a diet

Fermentation Characteristics, Tannin Contents and Ruminal Degradation of Green Tea and Black Tea By-products Ensiled at Different Temperatures

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Makoto Kondo

2014-07-01

Full Text Available Green and black tea by-products, obtained from ready-made tea industry, were ensiled at 10°C, 20°C, and 30°C. Green tea by-product silage (GTS and black tea by-product silage (BTS were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at 10°C. The GTS stored at 20°C and 30°C showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on NH3-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and NH3-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and NH3-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin’s activity in the rumen.

Energy and tannin extract supplementation for dairy cows on annual winter pastures

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Tiago Pansard Alves

2017-05-01

Full Text Available Energy supplementation can increase the consumption of metabolizable energy and substrate for microbial growth, while condensed tannins aid in increasing the duodenal flow of foodborne metabolizable proteins. The objective of this study was to evaluate the effects of energy supplementation and the inclusion of tannin extract (TE from Acacia mearnsii (Weibull Black, Tanac S. A., Montenegro, Brazil on the production performance of dairy cows grazing on winter pastures. Nine multiparous Holstein cows in mid lactation were distributed in a 3 × 3 Latin square experimental design over three periods of 28 days (21 adaptation and 7 sampling. The treatments were: without supplementation (WS, supplementation with 4 kg of corn grain (CG, and corn grain + 80 g of tannin extract (TE. The dry matter (DM intake from pastures was similar among treatments, but the consumption of DM of the supplement was higher in the CG treatment than that in the TE treatment. The total DM intake was higher for the supplemented animals (17.3 kg?day-1 than that for the unsupplemented animals (14.9 kg?day-1 and in the TE treatment (17.7 kg?day-1 than in the CG treatment (16.7 kg day-1. Milk production increased from the unsupplemented to the supplemented animals (20.9 to 23.5 kg, respectively, while the content of urea N in the milk decreased (12.6 to 10.5 mg?100 mL-1, respectively. There were no differences in milk production or content of milk urea N between the CG and TE treatments. Energy supplementation is a tool for improving the nutritional profile and the performance of dairy cows in mid lactation grazing on annual winter pastures, while tannin extract aids in improving the energy balance.

Red Wine Tannin Structure-Activity Relationships during Fermentation and Maceration.

Science.gov (United States)

Yacco, Ralph S; Watrelot, Aude A; Kennedy, James A

2016-02-03

The correlation between tannin structure and corresponding activity was investigated by measuring the thermodynamics of interaction between tannins isolated from commercial red wine fermentations and a polystyrene divinylbenzene HPLC column. Must and/or wine samples were collected throughout fermentation/maceration from five Napa Valley wineries. By varying winery, fruit source, maceration time, and cap management practice, it was considered that a reasonably large variation in commercially relevant tannin structure would result. Tannins were isolated from samples collected using low pressure chromatography and were then characterized by gel permeation chromatography and acid-catalyzed cleavage in the presence of excess phloroglucinol (phloroglucinolysis). Corresponding tannin activity was determined using HPLC by measuring the thermodynamics of interaction between isolated tannin and a polystyrene divinylbenzene HPLC column. This measurement approach was designed to determine the ability of tannins to hydrophobically interact with a hydrophobic surface. The results of this study indicate that tannin activity is primarily driven by molecular size. Compositionally, tannin activity was positively associated with seed tannins and negatively associated with skin and pigmented tannins. Although measured indirectly, the extent of tannin oxidation as determined by phloroglucinolysis conversion yield suggests that tannin oxidation at this stage of production reduces tannin activity. Based upon maceration time, this study indicates that observed increases in perceived astringency quality, if related to tannin chemistry, are driven by tannin molecular mass as opposed to pigmented tannin formation or oxidation. Overall, the results of this study give new insight into tannin structure-activity relationships which dominate during extraction.

Tannin quantification in red grapes and wine: comparison of polysaccharide- and protein-based tannin precipitation techniques and their ability to model wine astringency.

Science.gov (United States)

Mercurio, Meagan D; Smith, Paul A

2008-07-23

Quantification of red grape tannin and red wine tannin using the methyl cellulose precipitable (MCP) tannin assay and the Adams-Harbertson (A-H) tannin assay were investigated. The study allowed for direct comparison between the repeatability of the assays and for the assessment of other practical considerations such as time efficiency, ease of practice, and throughput, and assessed the relationships between tannin quantification by both analytical techniques. A strong correlation between the two analytical techniques was observed when quantifying grape tannin (r(2) = 0.96), and a good correlation was observed for wine tannins (r(2) = 0.80). However, significant differences in the reported tannin values for the analytical techniques were observed (approximately 3-fold). To explore potential reasons for the difference, investigations were undertaken to determine how several variables influenced the final tannin quantification for both assays. These variables included differences in the amount of tannin precipitated (monitored by HPLC), assay matrix variables, and the monomers used to report the final values. The relationship between tannin quantification and wine astringency was assessed for the MCP and A-H tannin assays, and both showed strong correlations with perceived wine astringency (r(2) = 0.83 and r(2) = 0.90, respectively). The work described here gives guidance to those wanting to understand how the values between the two assays relate; however, a conclusive explanation for the differences in values between the MCP and A-H tannin assays remains unclear, and further work in this area is required.

Condensed Tannin Concentrations of Three Lotus Species Grown in Different Environments Contenido de Taninos Condensados en Germoplasma de Tres Especies del Género Lotus en Diferentes Ambientes

Directory of Open Access Journals (Sweden)

Hernán Acuña

2008-03-01

Full Text Available Condensed tannins (CT present in Lotus spp., depending on their concentration in the plant, can prevent bloating and improve protein absorption in ruminants. With the objective to know the variability of this characteristic, the CT concentration (% dry matter basis was determined by the butanol-HCl procedure in 13 cultivars of Lotus corniculatus L. (Lc introduced from North and South America and Oceania, 11 accessions of Lotus tenuis Waldst. & Kit. ex Willd. (Lt, and 22 accessions of Lotus uliginosus Schkuhr (Lu collected in Chile, from 32° to 38° S and 36° to 46° S, respectively. The field experiments, with two randomized complete blocks, were established in autumn 1998, in five different environments in the central-southern zone of Chile (clay soil, sandy soil, and three volcanic soils with different levels of water availability. The herbage sampling was conducted in spring-summer 1999-2000, when the plants were in full flowering. Significant differences between cultivars or accessions were found within each site, in total CT and/or in extractable or protein or fiber bound fractions of CT concentrations. The Lc and Lu genotypes showed high variability, with a range of 4.7 to 8.7% and 6.3 to 11.0%, and means of 6.1 and 8.2%, respectively, of total CT. The Lt general mean was 4.8%, considerably higher than the figures reported in the literature, and had low variability. This information will contribute to select genotypes for the improvement of this species by selection and breedingLos taninos condensados (TC presentes en Lotus spp ., dependiendo de su concentración en la planta, pueden evitar el meteorismo y favorecer la absorción de proteína en rumiantes. Con el objetivo de conocer la variabilidad de esta característica se determinó por el método del butanol-HCl la concentración (% base materia seca de TC en 13 cultivares de Lotus corniculatus L. (Lc introducidos de Norteamérica, Sudamérica y Oceanía, 11 accesiones de Lotus

HPLC retention thermodynamics of grape and wine tannins.

Science.gov (United States)

Barak, Jennifer A; Kennedy, James A

2013-05-08

The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

Effect of tannins on the in vitro growth of Clostridium perfringens.

Science.gov (United States)

Elizondo, Ana M; Mercado, Elsa C; Rabinovitz, Bettina C; Fernandez-Miyakawa, Mariano E

2010-10-26

Vegetable tannins are water-soluble polyphenolic compounds of varying molecular weights that occur abundantly in nature. The diet of many free-ranging wild animals contains significant amounts of tannins. Also, commercial tannins are used in animal industry as food additives to improve animal performance. In order to further determine the capacity of tannins to inhibit the development of intestinal diseases produced by Clostridium pefringens, we evaluated here the effect of tannins from quebracho, chestnut or combinations of both on C. perfringens and their toxins. The C. perfringens (types A, B, C, D and E) growth obtained from the intestine of healthy and diseased animals was reduced in a dose-dependent manner in the presence of quebracho tannins, chestnut tannins, combinations of both or a commercial formula based in these tannins. Although the minimal inhibitory concentration of both tannins varied between isolates, no statistically significant differences were observed between isolates from healthy or sick animals. Comparative analysis showed that the concentrations of quebracho tannin inhibiting the growth of C. perfringens were higher than chestnut tannin. In fact, antibacterial effect of quebracho tannin was increased up to 20 times with the addition of 25% of chestnut tannin and 85 times with 75% of chestnut tannin. Antibacterial activity of the commercial product was up to ~50 times higher than quebracho tannin alone. Quebracho tannin showed partial bactericidal activity, whereas chestnut tannin activity was stronger. Both tannins were able to reduce the alpha toxin lecithinase activity and epsilon toxin cytotoxicity in MDCK cells. These results suggest that tannin-supplemented diet could be useful to prevent some clostridial diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

Characterization of oxidized tannins: comparison of depolymerization methods, asymmetric flow field-flow fractionation and small-angle X-ray scattering.

Science.gov (United States)

Vernhet, Aude; Dubascoux, Stéphane; Cabane, Bernard; Fulcrand, Hélène; Dubreucq, Eric; Poncet-Legrand, Céline

2011-09-01

Condensed tannins are a major class of plant polyphenols. They play an important part in the colour and taste of foods and beverages. Due to their chemical reactivity, tannins are not stable once extracted from plants. A number of chemical reactions can take place, leading to structural changes of the native structures to give so-called derived tannins and pigments. This paper compares results obtained on native and oxidized tannins with different techniques: depolymerization followed by high-performance liquid chromatography analysis, small-angle X-ray scattering (SAXS) and asymmetric flow field-flow fractionation (AF4). Upon oxidation, new macromolecules were formed. Thioglycolysis experiments showed no evidence of molecular weight increase, but thioglycolysis yields drastically decreased. When oxidation was performed at high concentration (e.g., 10 g L(-1)), the weight average degree of polymerization determined from SAXS increased, whereas it remained stable when oxidation was done at low concentration (0.1 g L(-1)), indicating that the reaction was intramolecular, yet the conformations were different. Differences in terms of solubility were observed; ethanol being a better solvent than water. We also separated soluble and non-water-soluble species of a much oxidized fraction. Thioglycolysis showed no big differences between the two fractions, whereas SAXS and AF4 showed that insoluble macromolecules have a weight average molecular weight ten times higher than the soluble ones.

Mangrove-sponge associations: a possible role for tannins

NARCIS (Netherlands)

Hunting, E.R.; van der Geest, H.G.; Krieg, A.J.; van Mierlo, M.B.L.; van Soest, R.W.M.

2010-01-01

A positive correlation between sponge coverage and tannin concentrations in prop roots of Rhizophora mangle L. has previously been reported. However, the ecological role of tannins within the mangrove sponge association remains speculative. This study investigated whether tannins play a role in

High-performance liquid chromatography determination of red wine tannin stickiness.

Science.gov (United States)

Revelette, Matthew R; Barak, Jennifer A; Kennedy, James A

2014-07-16

Red wine astringency is generally considered to be the sensory result of salivary protein precipitation following tannin-salivary protein interaction and/or tannin adhering to the oral mucosa. Astringency in red wine is often described using qualitative terms, such as hard and soft. Differences in qualitative description are thought to be due in part to the tannin structure. Tannin chemistry contributions to qualitative description have been shown to correlate with the enthalpy of interaction between tannin and a hydrophobic surface. On the basis of these findings, a method was developed that enabled the routine determination of the thermodynamics of the tannin interaction with a hydrophobic surface (polystyrene divinylbenzene) for tannins in red wine following direct injection. The optimized analytical method monitored elution at four different column temperatures (25-40 °C, in 5 °C increments), had a 20 min run time, and was monitored at 280 nm. The results of this study confirm that the calculated thermodynamics of the interaction are intensive and, therefore, provide specific thermodynamic information. Variation in the enthalpy of interaction between tannin and a hydrophobic surface (tannin stickiness) is a unique, concentration-independent analytical parameter. The method, in addition to providing information on tannin stickiness, provides the tannin concentration.

THE FATE OF TANNINS IN CORSICAN PINE LITTER

NARCIS (Netherlands)

Nierop, K.G.J.; Verstraten, J.M.

2006-01-01

Tannins are ubiquitous in higher plants and therefore also in litter and soils where they affect many biogeochemical processes. Despite this well recognized role, the fate of tannins in litter and mineral soils is hardly known as often only trace amounts, if any, of tannins are measured. In this

Hydrolyzable tannins of tamaricaceous plants. V. Structures of monomeric-trimeric tannins and cytotoxicity of macrocyclic-type tannins isolated from Tamarix nilotica (1).

Science.gov (United States)

Orabi, Mohamed A A; Taniguchi, Shoko; Sakagami, Hiroshi; Yoshimura, Morio; Yoshida, Takashi; Hatano, Tsutomu

2013-05-24

Three new ellagitannin monomers, nilotinins M5-M7 (1-3), a dimer, nilotinin D10 (4), and a trimer, nilotinin T1 (5), together with three known dimers, hirtellin D (7) and tamarixinins B (8) and C (9), and a trimer, hirtellin T2 (6), were isolated from Tamarix nilotica dried leaves. The structures of the tannins were elucidated by intensive spectroscopic methods and chemical conversions into known tannins. The new trimer (5) is a unique macrocyclic type whose monomeric units are linked together by an isodehydrodigalloyl and two dehydrodigalloyl moieties. Additionally, dimeric and trimeric macrocyclic-type tannins isolated from T. nilotica in this study were assessed for possible cytotoxic activity against four human tumor cell lines. Tumor-selective cytotoxicities of the tested compounds were higher than those of synthetic and natural potent cytotoxic compounds, including polyphenols, and comparable with those of 5-fluorouracil and melphalan.

Tannins: current knowledge of food sources, intake, bioavailability and biological effects.

Science.gov (United States)

Serrano, José; Puupponen-Pimiä, Riitta; Dauer, Andreas; Aura, Anna-Marja; Saura-Calixto, Fulgencio

2009-09-01

Tannins are a unique group of phenolic metabolites with molecular weights between 500 and 30 000 Da, which are widely distributed in almost all plant foods and beverages. Proanthocyanidins and hydrolysable tannins are the two major groups of these bioactive compounds, but complex tannins containing structural elements of both groups and specific tannins in marine brown algae have also been described. Most literature data on food tannins refer only to oligomeric compounds that are extracted with aqueous-organic solvents, but a significant number of non-extractable tannins are usually not mentioned in the literature. The biological effects of tannins usually depend on their grade of polymerisation and solubility. Highly polymerised tannins exhibit low bioaccessibility in the small intestine and low fermentability by colonic microflora. This review summarises a new approach to analysis of extractable and non-extractable tannins, major food sources, and effects of storage and processing on tannin content and bioavailability. Biological properties such as antioxidant, antimicrobial and antiviral effects are also described. In addition, the role of tannins in diabetes mellitus has been discussed.

TANNIN CONTENT DETERMINATION IN THE BARK OF Eucalyptus spp

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Paulo Fernando Trugilho

2003-07-01

Full Text Available The objective of this study was to determine the tannin contents in the bark oftwenty-five species of Eucalyptus through two extraction methods, one using hot water andthe other a sequence of toluene and ethanol. The results showed that the extraction methodspresented significant differences in the tannin contents. The method using the sequencetoluene and ethanol, for most of the species, promoted a larger extraction of tannin. The hotwater method presented higher contents of tannin for Eucalyptus cloeziana (40,31%,Eucalyptus melanophoia (20,49% and Eucalyptus paniculata (16,03%. In the toluene andethanol method the species with higher tannin content was Eucalyptus cloeziana (31,00%,Eucalyptus tereticornis (22,83% and Eucalyptus paniculata (17,64%. The Eucalyptuscloeziana presented great potential as commercial source of tannin, independent of theextraction method considered.

Impact of noncovalent interactions between apple condensed tannins and cell walls on their transfer from fruit to juice: studies in model suspensions and application.

Science.gov (United States)

Le Bourvellec, Carine; Le Quere, Jean-Michel; Renard, Catherine M G C

2007-09-19

The adsorption of procyanidins (condensed tannins) on cell-wall material was quantified by bringing into contact solutions of procyanidins and suspensions of cell-wall material. A model was developed on the basis of the Langmuir isotherm formulation and a factorial experimental design. The parameters that influenced the adsorption were the concentration and molecular weight of the procyanidins, the ionic strength of the solution, the temperature, and the apple cell-wall concentration. The model was applied to partitioning of procyanidins from apple between juice and mash. The parameters to be taken into account are the composition of the apples and, specifically, (i) the concentration and molecular weight of the procyanidins, (ii) their acidity and pH as a determinant of the ionic strength, and (iii) their cell-wall content and the temperature at pressing. To estimate the ability of the model to relate procyanidin concentrations in the juice to their concentration in the apple, apples of three varieties of widely different procyanidin compositions were pressed in conditions that prevent oxidation. In these conditions, yields in the juice were >80% for phenolic acids or catechin monomers but <50% for procyanidins, with the lowest rates obtained for the higher polymers in accordance with the model.

A role for anthocyanin in determining wine tannin concentration in Shiraz.

Science.gov (United States)

Kilmister, Rachel L; Mazza, Marica; Baker, Nardia K; Faulkner, Peta; Downey, Mark O

2014-01-01

Four wines were made to investigate the effect of different anthocyanin and tannin fruit concentrations on wine phenolics and colour. Wines that were made from fruit with high anthocyanin concentration had high tannin concentrations regardless of the concentration of tannin in fruit, while wines made from fruit with low anthocyanin also had low tannin concentration. It was found that fruit anthocyanin concentration correlated with wine tannin concentration, wine colour and polymeric pigment formation. Anthocyanin concentration might be a key component for increasing tannin solubility and extraction into wine and the formation of polymeric pigments. Industry implications include managing tannin and anthocyanin fruit concentration for targeting tannin extraction and polymeric pigment formation in wine. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Determination of Tannins of Three Common Acacia Species of Sudan

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Isam Eldin Hussein Elgailani

2014-01-01

Full Text Available The objective of this study is to analyze and compare tannins of three common Acacia species of Sudan, since vegetable tannins are important in leather industry. Acacia nilotica and Acacia seyal samples were collected from Sunt Forest in Khartoum State, while Acacia senegal samples were collected from the Debabat Forest in South Kordofan State. Bark samples from bulk collections of the three Acacia species were extracted with boiled deionized water. The amount of tannins present in these bulk samples was determined by Folin-Denis method for total phenolic materials, followed by precipitation with hide-powder. The difference between the amount of phenolic materials present before and after addition of hide-powder represents the amount of tannins present. The percentage of tannins in the leaves, bark, and mature and immature fruits of collections of individuals of Acacia species was estimated; mature and immature fruits of Acacia nilotica contain tannins (22.15% and 22.10%, resp.. The leaves of Acacia nilotica and Acacia seyal contain tannins (11.80% and 6.30%, resp.. The barks of Acacia seyal, Acacia nilotica, and Acacia senegal contain tannins (12.15%, 10.47%, and 3.49%, resp..

Biological Activity of Tannins from Acacia mangium Bark Extracted by Different Solvents

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E. Wina

2010-08-01

Full Text Available Acacia mangium bark is abundant byproduct of wood industry in Indonesia. It is underutilized and mainly used as fire wood for the wood industry. The bark contains high level of tannin but the tannin has not been extracted or produced commercially. Tannin isolate can be used for several purposes such as tanning agent for leather, adhesive for plywood or particle board, etc. In ruminant, tannin can be detrimental but can also be beneficial. This experiment was aimed of getting the highest yield of tannin extract with the highest biological activity in rumen fermentation. Nine different solvents at different temperatures were used to extract tannin from A. mangium bark. The extracts were analyzed for their tannin contents and biological activities. Tannin content was analyzed using folin ciocalteau and butanol-HCl methods. Biological activity was described as a percentage of an increase in gas production in the in vitro rumen-buffer fermentation, with and without addition of PEG. The results show that Na2SO3 solution extracted more tannin than other solutions and the higher the concentration of Na2SO3 solution, the higher the yield of tannin extract. The solution of 6% sodium sulphite gave the highest yield of tannin extract (31.2% of original bark sample and the highest concentration of tannin (18.26% but produced a negative effect on in vitro fermentation (% increase of gas production = 2.70%. Extraction with 50% acetone gave a high yield of extract (22.28% of original bark which contained 12.98% of tannin and showed the highest biological response (% increase of gas production = 216%. In conclusion, sodium sulphite solution is not recommended for tannin extraction if the tannin will be used as feed additive in ruminant feed; on the other hand, the aqueous acetone (50% acetone solution is a better choice to be used.

Characterization of tannin-based adhesives from Acacia mangium barks

International Nuclear Information System (INIS)

Siti Fatahiyah Mohamada; Pizzi, Antonio

2010-01-01

The aim of this work is to demonstrate the performances of Acacia Mangium tannin-based tannin designed as adhesive in the particleboard production. The tannin was extracted from acacia mangium barks in differences medium extraction. Three difference medium, (1)Water (Control), (2)Na 2 SO 3 (4 %) / Na 2 CO 3 (0.4 %) and (3) Na 2 SO 3 (8 %) / Na 2 CO 3 (0.8 %) used, the (3) medium extraction produce then highest yield (25.8 %) follow the (2) medium extraction (21.6%) and the less yield (17.7%). To evaluate the mechanical performances of optimal Acacia mangium tannin-based adhesives, particleboard were produced using 3 differences hardener and mechanical properties (Internal bonding) were investigated. The performance of these panels is comparable to those of particle panels commercial. The results showed that particleboard panels bonded with parafomaldehid (0.392 Mpa) exhibited better mechanical properties, continue particleboard panel hardened with hexamine (0.367 MPa) and particleboard panel bonded with glyoxol-tannin based adhesives (0.244 MPa). This show the suitable harder for acacia mangium tannin are formaldehyde > hexamine > glyoxol. (author)

Effect of wine dilution on the reliability of tannin analysis by protein precipitation

DEFF Research Database (Denmark)

Jensen, Jacob Skibsted; Werge, Hans Henrik Malmborg; Egebo, Max

2008-01-01

A reported analytical method for tannin quantification relies on selective precipitation of tannins with bovine serum albumin. The reliability of tannin analysis by protein precipitation on wines having variable tannin levels was evaluated by measuring the tannin concentration of various dilutions...... of five commercial red wines. Tannin concentrations of both very diluted and concentrated samples were systematically underestimated, which could be explained by a precipitation threshold and insufficient protein for precipitation, respectively. Based on these findings, we have defined a valid range...... of the tannin response in the protein precipitation-tannin assay, which suffers minimally from these problems....

Linkage Map of a Gene Controlling Zero Tannins (zt-1 in Faba Bean (Vicia faba L. with SSR and ISSR Markers

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Wanwei Hou

2018-05-01

Full Text Available Faba bean (Vicia faba L., a partially allogamous species, is rich in protein. Condensed tannins limit the use of faba beans as food and feed. Two recessive genes, zt-1 and zt-2, control the zero tannin content in faba bean and promote a white flower phenotype. To determine the inheritance and develop a linkage map for the zt-1 gene in the faba bean germplasm M3290, F2 and F3 progenies were derived from the purple flower and high tannin content genotypes Qinghai12 and zt-1 line M3290, respectively. Genetic analysis verified a single recessive gene for zero tannin content and flower colour. In total, 596 SSR markers and 100 ISSR markers were used to test the polymorphisms between the parents and bulks for the contrasting flower colour via Bulked Segregant Analysis (BSA. Subsequently, six SSR markers and seven ISSR markers were used to genotype the entire 413 F2 population. Linkage analysis showed that the zt-1 gene was closely linked to the SSR markers SSR84 and M78, with genetic distances of 2.9 and 5.8 cM, respectively. The two flanked SSR markers were used to test 34 faba bean genotypes with different flower colours. The closely linked SSR marker SSR84 predicted the zt-1 genotypes with absolute accuracy. The results from the marker-assisted selection (MAS from this study could provide a solid foundation for further faba bean breeding programmes.

Tannins quantification in barks of Mimosa tenuiflora and Acacia mearnsii

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Leandro Calegari

2016-03-01

Full Text Available Due to its chemical complexity, there are several methodologies for vegetable tannins quantification. Thus, this work aims at quantifying both tannin and non-tannin substances present in the barks of Mimosa tenuiflora and Acacia mearnsii by two different methods. From bark particles of both species, analytical solutions were produced by using a steam-jacketed extractor. The solution was analyzed by Stiasny and hide-powder (no chromed methods. For both species, tannin levels were superior when analyzed by hide-powder method, reaching 47.8% and 24.1% for A. mearnsii and M. tenuiflora, respectively. By Stiasny method, the tannins levels considered were 39.0% for A. mearnsii, and 15.5% for M. tenuiflora. Despite the best results presented by A. mearnsii, the bark of M. tenuiflora also showed great potential due to its considerable amount of tannin and the availability of the species at Caatinga biome.

Oxygen consumption rates by different oenological tannins in a model wine solution.

Science.gov (United States)

Pascual, Olga; Vignault, Adeline; Gombau, Jordi; Navarro, Maria; Gómez-Alonso, Sergio; García-Romero, Esteban; Canals, Joan Miquel; Hermosín-Gutíerrez, Isidro; Teissedre, Pierre-Louis; Zamora, Fernando

2017-11-01

The kinetics of oxygen consumption by different oenological tannins were measured in a model wine solution using the non-invasive method based on luminiscence. The results indicate that the oxygen consumption rate follows second-order kinetics depending on tannin and oxygen concentrations. They also confirm that the oxygen consumption rate is influenced by temperature in accordance with Arrhenius law. The indications are that ellagitannins are the fastest oxygen consumers of the different oenological tannins, followed in decreasing order by quebracho tannins, skin tannins, seed tannins and finally gallotannins. This methodology can therefore be proposed as an index for determining the effectiveness of different commercial tannins in protecting wines against oxidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in enzymes, phenolic compounds, tannins, and vitamin C in various stages of jambolan (Syzygium cumini Lamark development

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Taís Silva de Oliveira Brandão

2011-12-01

Full Text Available The physiological state of a fruit is closely related to ripening and climatic conditions during the growing period when the fruit undergo changes in color, texture, and flavor. The ripening of the fruit can involve a complex series of biochemical reactions with alteration in enzymes activities, phenols, tannins, and ascorbic acid. The activity of enzymes (carboximethylcellulase, polygalacturonase, and pectinlyase, the total concentration of phenolic compounds, condensed tannins, and vitamin C in five stages of maturation were studied. Significant changes were observed between the maturity stages. The phenolic compounds were higher at green stage (705.01 ± 7.41; tannins were higher at green/purple stage (699.45 ± 0.22. The results showed that the ascorbic acid levels of the pulp varied significantly from 50.81 ± 1.43 to 6.61 ± 1.04 mg.100 g-1 during maturation. The specific activity of pectin lyase was higher at green stage (1531.90 ± 5.83. The specific activity of polygalacturonase was higher at mature stage (1.83 ± 0.0018. The specific activity of carboximetilcelulose was higher at ripe mature stage (4.61 ± 0.0024. The low ascorbic acid content found in jambolan fruit indicates that this fruit is not a rich source of this nutrient; however, other characteristics can make jambolan products fit for human consumption.

Tannin structural elucidation and quantitative ³¹P NMR analysis. 2. Hydrolyzable tannins and proanthocyanidins.

Science.gov (United States)

Melone, Federica; Saladino, Raffaele; Lange, Heiko; Crestini, Claudia

2013-10-02

An unprecedented analytical method that allows simultaneous structural and quantitative characterization of all functional groups present in tannins is reported. In situ labeling of all labile H groups (aliphatic and phenolic hydroxyls and carboxylic acids) with a phosphorus-containing reagent (Cl-TMDP) followed by quantitative ³¹P NMR acquisition constitutes a novel fast and reliable analytical tool for the analysis of tannins and proanthocyanidins with significant implications for the fields of food and feed analyses, tannery, and the development of natural polyphenolics containing products.

Sensory properties of wine tannin fractions: implications for in-mouth sensory properties.

Science.gov (United States)

McRae, Jacqui M; Schulkin, Alex; Kassara, Stella; Holt, Helen E; Smith, Paul A

2013-01-23

Different molecular structures of grape tannins have been shown to influence astringency, however, the in-mouth sensory effects of different molecular structures in red wine tannins remains to be established. The objective of this research was to assess the impact of wine tannin structure on in-mouth sensory properties. Wine tannin was isolated from Cabernet Sauvignon wines of two vintages (3 and 7 years old) and separated into two structurally distinct subfractions with liquid-liquid fractionation using butanol and water. The aqueous subfractions had greater mean degree of polymerization (mDp) and contained a higher proportion of epigallocatechin subunits than the butanol-soluble subfractions, while the older wine tannin fractions showed fewer epicatechin gallate subunits than the younger tannin fractions. The red wine had approximately 3:1 mass ratio of the aqueous and butanol tannin subfractions which approximated an equimolar ratio of tannin in each subfraction. Descriptive sensory analysis of the tannin subfractions in model wine at equimolar concentrations revealed that the larger, more water-soluble wine tannin subfractions from both wines were perceived as more astringent than the smaller, more hydrophobic and more highly pigmented butanol-soluble subfractions, which were perceived as hotter and more bitter. Partial least squares analysis indicated that the greater hydrophobicity and color incorporation in the butanol fractions was negatively associated with astringency, and these characteristics are also associated with aged wine tannins. As the larger, water-soluble tannins had a greater impact on the overall wine astringency, winemaking processes that modulate concentrations of these are likely to most significantly influence astringency.

Tannin bark Melalauca cajuputi powell (gelam) as green corrosion inhibitor of mild steel

Energy Technology Data Exchange (ETDEWEB)

Talib, Nur Atiqah Abu; Zakaria, Sarani; Hua, Chia Chin; Othman, Norinsan Kamil [School of Applied Physic, Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

2014-09-03

Tannin was extracted from gelam bark and used to produce corrosion inhibitor for mild steel. Tannin was extracted from gelam bark using 70% aqueous acetone for 6 hour. Tannin powder was characterization using fourier transform infrared spectroscopy to analyse chemical component in tannin and Scanning electron microscope (SEM) for tannin physical structure. The tannin effect on the corrosion inhibition of mild steel has been investigated in 1Mol HCl solution for 6 hour followed ASTM. The weight loss method were applied to study the mild steel corrosion behavior in the present and absend of different concentration of tannin (250, 300, 350)ppm. Tannin act good inhibitor as corrosion inhibitor for mild steel in acid medium. Surface morphology of carbon steel with and without inhibitor was investigated by scanning electron microscopy.

Vegetable Tannins Used in the Manufacture of Historic Leathers

OpenAIRE

Lina Falcão; Maria Eduarda M. Araújo

2018-01-01

In this review, a brief description of how animal skins were transformed in leathers in Europe using different vegetable tannins will be presented. Special attention will be dedicated to the description of the type of tannins and the characteristics of the most important type of historic leathers thus obtained. The text will also focus on the description of the techniques used in the identification of these tannins in historic objects: colorimetric tests and spectroscopic analysis.

Spectrophotometric determination of tannins by phosphotungstic-phosphomolybdic reagent

Energy Technology Data Exchange (ETDEWEB)

Reicher, F; Sierakowski, M R; Correa, J B.C. [Parana Univ., Curitiba (Brazil). Dept. de Bioquimica

1981-01-01

There are several colorimetric techniques to determine tannins in plant extracts. One frequently used is the Folin method (phosphotungstic acid reagent) that procedures a blue color with phenolic compounds. However, this coloured complex is unstable. With the Folin-Ciocalteau reagent, used in protein determination (Lowry et al. J.B.C. 193: 265, 1951) good results were obtained, even in the absence of cooper solution. Using phosphotungstic-phosphomolybdic reagent (Folin-Denis), it was obtained maximum color with 1,0 ml of the reagent in 20 minutes, after the additon of 10 ml 20% sodium carbonate solution. Tannins samples containing 10 to 200 ..mu..g/ml were analysed. Absorbances are determined at 720 or 600 nm. Tannins of commercial preparations from Acacia negra were analysed by the phosphotungstic-phosphomolybdic reagent before (A) and after (B) treatment with chromate hyde powder. By this procedure hydrolysible tannins were determined (A-B).

Spectrophotometric determination of tannins by phosphotungstic-phosphomolibdic reagent

International Nuclear Information System (INIS)

Reicher, F.; Sierakowski, M.R.; Correa, J.B.C.

1981-01-01

There are several colorimetric techniques to determine tannins in plant extracts. One frequently used is the Folin method (phosphotungstic acid reagent) that procedures a blue color with phenolic compounds. However, this coloured complex is unstable. With the Folin-Ciocalteau reagent, used in protein determination (Lowry et al. J.B.C. 193: 265, 1951) good results were obtained, even in the absence of cooper solution. Using phosphotungstic-phosphomolibdic reagent (Folin-Denis), it was obtained maximum color with 1,0 ml of the reagent in 20 minutes, after the adition of 10 ml 20% sodium carbonate solution. Tannins samples containing 10 to 200 μg/ml were analysed. Absorbances are determined at 720 or 600 nm. Tannins of commercial preparations from Acacia negra were analysed by the phosphotungstic-phosphomolibdic reagent before (A) and after (B) treatment with chromate hyde powder. By this procedure hydrolysible tannins were determined (A-B). (Author) [pt

Multifunctional porous solids derived from tannins

Science.gov (United States)

Celzard, Alain; Fierro, Vanessa; Pizzi, Antonio; Zhao, Weigang

2013-03-01

Tannins are extremely valuable, non toxic, wood extractives combining reactivity towards aldehydes, low cost, natural origin and easy handling. When polymerized in the presence of suitable chemicals including blowing agent, ultra lightweight rigid tannin-based foams are obtained. If pyrolyzed under inert gas, reticulated carbon foams having the same pore structure and the same density are obtained. The most remarkable features of tannin-based foams are the following: mechanical resistance similar to, or higher than, that of commercial phenolic foams, tuneable pore size and permeability, infusibility, very low thermal conductivity, cheapness, ecological character, high resistance to flame and to chemicals. Carbon foams have even better properties and are also electrically conducting. Consequently, various applications are suggested for organic foams: cores of sandwich composite panels, sound and shock absorbers and thermal insulators, whereas carbon foams can be used as porous electrodes, filters for molten metals and corrosive chemicals, catalyst supports and adsorbents.

Vegetable Tannins Used in the Manufacture of Historic Leathers

Directory of Open Access Journals (Sweden)

Lina Falcão

2018-05-01

Full Text Available In this review, a brief description of how animal skins were transformed in leathers in Europe using different vegetable tannins will be presented. Special attention will be dedicated to the description of the type of tannins and the characteristics of the most important type of historic leathers thus obtained. The text will also focus on the description of the techniques used in the identification of these tannins in historic objects: colorimetric tests and spectroscopic analysis.

Enhancement of both salivary protein-enological tannin interactions and astringency perception by ethanol.

Science.gov (United States)

Obreque-Slíer, Elías; Peña-Neira, Alvaro; López-Solís, Remigio

2010-03-24

Red wine astringency has been associated with interactions of tannins with salivary proteins. Tannins are active protein precipitants. Not much evidence exists demonstrating contribution of other wine components to astringency. We aimed to investigate an eventual role of ethanol both in astringency and salivary protein-enological tannin interactions. A trained sensory panel scored perceived astringency. Salivary protein-tannin interactions were assessed by observing both tannin-dependent changes in salivary protein diffusion on cellulose membranes and tannin-induced salivary protein precipitation. Proanthocyanidins and gallotannins in aqueous and hydroalcoholic solutions were assayed. A biphasic mode of diffusion on cellulose membranes displayed by salivary proteins was unaffected after dilution with water or enological concentrations of ethanol. At those concentrations ethanol was not astringent. In aqueous solution, tannins provoked both restriction of salivary protein diffusion, protein precipitation, and astringency. Those effects were exacerbated by 13% ethanol. In summary, enological concentrations of ethanol exacerbate astringency and salivary protein-tannin interactions.

Determination of Tannin and Saponin Dosage for Defaunation Improvement Feed Fermentability

OpenAIRE

Wahyuni, I.M. D; Muktiani, A; Christianto, M

2014-01-01

The research was conducted to evaluate the effect of addition of tannin, saponin or combination of tannin and saponin to the concentrate of the ration on the microbial population and fermentability of feed in vitro and to assess the best dosage of uses. The research was arranged according to completely randomized design with four treatments and 3 replications. The treatments were ration without tannin and saponin (T0), ration with 1.2% saponin (T1), ration with 0.5% tannin and 0.9% saponin (T...

Chemical composition of Lablab purpureus and Vigna unguiculata ...

African Journals Online (AJOL)

Esnart Mukumbo

2018-02-06

Feb 6, 2018 ... condensed tannins, and saponins using standard methods. ..... Analysis of variance was used to determine the effects of legume species and ..... of tannins in the plant kingdom: hydrolysable tannins (HTs) and condensed.

Assessment of tannin variation in Tamarisk foliage across a latitudinal gradient

Science.gov (United States)

Hussey, A.M.; Kimball, B.A.; Friedman, J.M.

2011-01-01

Certain phenotypic traits of plants vary with latitude of origin. To understand if tannin concentration varies among populations of tamarisk (Tamarix spp.) according to a latitudinal gradient, an analytical method was adapted from an enological tannin assay. The tannin content (wet basis) of tamarisk foliage collected from 160 plants grown in a common garden ranged from 8.26 to 62.36 mg/g and was not correlated with the latitude of the original North American plant collection site. Tannins do not contribute to observed differences in herbivory observed among these tamarisk populations.

TANNIN ADHESIVES AS AN ALTENATIVE TO THE SYNTHETIC PHENOLIC ADHESIVES

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Semra Çolak

2003-04-01

Full Text Available Recently, increasing attention has been paid industrially to the use of tannin formaldehyde adhesives in production of wood based panel products such as particleboard, fiber board and plywood. The researches on the use of tannin extracts as a wood adhesive started in 1950, however, they proceeded very slowly since the problems associated with the application of them. The idea which tannin extract can be used replace the oil-based phenolic adhesive was the base of several studies after the oil crisis of the 1970s. In the past, the economical aspects were important in the researches on the tannin-based adhesives. Nowadays, however, both economical and ecological factors should have taken into consideration in wood bonding.

FONTES E APLICAÇÕES DE TANINOS E TANASES EM ALIMENTOS SOURCE AND APPLICATION OF TANNIN AND TANNASE IN FOODS.

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V. BATTESTIN

2008-08-01

Full Text Available

Os taninos ocorrem em uma ampla variedade de vegetais, são classificados em hidrolisáveis e condensados. O ácido tânico é um tanino hidrolisável, que é quebrado por enzimas. São utilizados para estabilização da cerveja, curtimento de pele e produção de resinas. Atualmente, são empregados em processos biotecnológicos para produção de enzimas como a tanase, que hidrolisa ésteres e ligações laterais de taninos hidrolisáveis produzindo ácido gálico e glicose. A maior aplicação desta enzima tem sido para produção de ácido gálico, que é utilizado na produção de trimetropim e sínteses de ésteres como propil galato, usado como antioxidante na indústria de alimentos. A enzima também é aplicada no processamento de cerveja e clarificação de sucos, processamento de chás instantâneos e tratamento de efluentes contaminados com compostos fenólicos. Tannins occur in an ample variety of vegetables and are classified in condensed and hydrolysable tannins. The tannic acid is a hydrolysable tannin that is broken by enzymes. Tannins are used for stabilization of the beer and resin production. Currently, they are used in biotechnological processes for enzyme production as tannase which hydrolyses ester and depside bonds of hydrolysable tannins releasing gallic acid and glucose. The major applications of this enzyme are in the production of gallic acid, which is used for the manufacture of an trimethoprim and synthesis of esters, such as propyl gallate, used as antioxidants in the food industry. The enzyme also has its applications in the production of beer and juices as a clarifier, in the manufacture of instant tea, and the treatment of wastewater contaminated with polyphenolic compounds.

Octanol-water partition coefficients for predicting the effects of tannins in ruminant nutrition.

Science.gov (United States)

Mueller-Harvey, Irene; Mlambo, Victor; Sikosana, Joe L N; Smith, Tim; Owen, Emyr; Brown, Ron H

2007-07-11

Tannins can cause beneficial or harmful nutritional effects, but their great diversity has until now prevented a rational distinction between tannin structures and their nutritional responses. An attempt has been made to study this problem by examining the octanol-water solubilities of tannins. A relatively simple HPLC method has been developed for screening mixtures of plant tannins for their octanol-water partition coefficients (Kow coefficients). Tannins were isolated from the fruits and leaves of different Acacia, Calliandra, Dichrostachys, and Piliostigma species, which are known to produce beneficial or harmful effects. The Kow coefficients of these tannins ranged from 0.061 to 13.9, average coefficients of variation were 9.2% and recoveries were 107%. Acacia nilotica fruits and leaves had the highest Kow coefficients, that is, 2.0 and 13.9, respectively. These A. nilotica products also have high concentrations of tannins. The combined effects of high octanol solubilities and high tannin concentrations may explain their negative effects on animal nutrition and health. It is known that compounds with high octanol solubilities are more easily absorbed into tissues, and it is, therefore, proposed that such compounds are more likely to cause toxicity problems especially if consumed in large quantities. According to the literature, tannins in human foods tend to have low Kow coefficients, and this was confirmed for the tannins in Piliostigma thonningii fruits. Therefore, unconventional feeds or browse products should be screened not only for their tannin concentrations but also for low octanol-water partition coefficients in order to identify nutritionally safe feeds and to avoid potentially toxic feeds.

Rapid determination of tannins in tanning baths by adaptation of BSA method.

Science.gov (United States)

Molinari, R; Buonomenna, M G; Cassano, A; Drioli, E

2001-01-01

A rapid and reproducible method for the determination of tannins in vegetable tanning baths is proposed as a modification of the BSA method for grain tannins existing in literature. The protein BSA was used instead of leather powder employed in the Filter Method, which is adopted in Italy and various others countries of Central Europe. In this rapid method the tannin contents is determined by means a spectrophotometric reading and not by means a gravimetric analysis of the Filter Method. The BSA method, which belongs to mixed methods (which use both precipitation and complexation of tannins), consists of selective precipitation of tannin from a solution containing also non tannins by BSA, the dissolution of precipitate and the quantification of free tannin amount by its complexation with Fe(III) in hydrochloric solutions. The absorbance values, read at 522 nm, have been expressed in terms of tannic acid concentration by using a calibration curve made with standard solutions of tannic acid; these have been correlated with the results obtained by using the Filter Method.

Correlation of Electropenetrography Waveforms From Lygus lineolaris (Hemiptera: Miridae) Feeding on Cotton Squares With Chemical Evidence of Inducible Tannins.

Science.gov (United States)

Cervantes, Felix A; Backus, Elaine A; Godfrey, Larry; Wallis, Christopher; Akbar, Waseem; Clark, Thomas L; Rojas, Maria G

2017-10-01

Probing behavior of Lygus lineolaris (Palisot de Beauvois) has previously been characterized with electropenetrography (EPG). Cell rupturing (CR) and ingestion (I) EPG waveforms were identified as the two main stylet-probing behaviors by adult L. lineolaris. However, characterization and identification of EPG waveforms are not complete until specific events of a particular waveform are correlated to insect probing. With the use of EPG, histology, microscopy, and chemical analysis, probing behavior of L. lineolaris on pin-head cotton squares was studied. Occurrences of waveforms CR and I were artificially terminated during the EPG recording. Histological samples of probed cotton squares were prepared and analyzed to correlate specific types and occurrences of feeding damage location and plant responses to insect feeding. Both CR and I occurred in the staminal column of the cotton square. Cell rupturing events elicited the production of dark-red deposits seen in histological staining that were demonstrated via chemical analysis to contain condensed tannins. We hypothesize that wounding and saliva secreted during CR triggered release of tannins, because tannin production was positively correlated with the number of probes with single CR events performed by L. lineolaris. Degraded plant tissue and tannins were removed from the staminal column during occurrence of waveform I. These results conclude the process of defining CR and I as probing waveforms performed by L. lineolaris on pin-head cotton squares. These biological definitions will now allow EPG to be used to quantitatively compare L. lineolaris feeding among different plant treatments, with the goal of improving pest management tactics against this pest. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Bacterial mechanisms to overcome inhibitory effects of dietary tannins

NARCIS (Netherlands)

Smith, A.H.; Zoetendal, E.G.; Mackie, R.I.

2005-01-01

High concentrations of tannins in fodder plants inhibit gastrointestinal bacteria and reduce ruminant performance. Increasing the proportion of tannin-resistant bacteria in the rumen protects ruminants from antinutritional effects. The reason for the protective effect is unclear, but could be

Enhanced antioxidant activity of polyolefin films integrated with grape tannins.

Science.gov (United States)

Olejar, Kenneth J; Ray, Sudip; Kilmartin, Paul A

2016-06-01

A natural antioxidant derived from an agro-waste of the wine industry, grape tannin, was incorporated by melt blending into three different polyolefins (high-density polyethylene, linear low-density polyethylene and polypropylene) to introduce antioxidant functionality. Significant antioxidant activity was observed at 1% tannin inclusion in all polymer blends. The antioxidant activity was observed to increase steadily with a greater concentration of grape tannins, the highest increases being seen with polypropylene. The mechanical and thermal properties of the polymer films following antioxidant incorporation were minimally altered with up to 3% grape tannins. All of the polyolefin-grape tannin films successfully passed the leachability test following USP661 standard protocol. Superior antioxidant activity was established in polyolefin thin films by utilization of a bulk grape extract obtained from winery waste. Significant increases in antioxidant activity were seen with 1% extract inclusion. This not only demonstrates the potential for food packaging applications of the polyolefin blends, but also valorizes the agro-waste. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Tannin structural elucidation and quantitative ³¹P NMR analysis. 1. Model compounds.

Science.gov (United States)

Melone, Federica; Saladino, Raffaele; Lange, Heiko; Crestini, Claudia

2013-10-02

Tannins and flavonoids are secondary metabolites of plants that display a wide array of biological activities. This peculiarity is related to the inhibition of extracellular enzymes that occurs through the complexation of peptides by tannins. Not only the nature of these interactions, but more fundamentally also the structure of these heterogeneous polyphenolic molecules are not completely clear. This first paper describes the development of a new analytical method for the structural characterization of tannins on the basis of tannin model compounds employing an in situ labeling of all labile H groups (aliphatic OH, phenolic OH, and carboxylic acids) with a phosphorus reagent. The ³¹P NMR analysis of ³¹P-labeled samples allowed the unprecedented quantitative and qualitative structural characterization of hydrolyzable tannins, proanthocyanidins, and catechin tannin model compounds, forming the foundations for the quantitative structural elucidation of a variety of actual tannin samples described in part 2 of this series.

Antioxidant activity of commercial food grade tannins exemplified in a wine model.

Science.gov (United States)

Ricci, Arianna; Olejar, Kenneth J; Parpinello, Giuseppina P; Mattioli, Alessia U; Teslić, Nemanja; Kilmartin, Paul A; Versari, Andrea

2016-12-01

Although commercial tannins are widely used in foods and beverages, an improved understanding of the structure and composition of vegetable tannins is needed to promote the exploitation of agri-food by-products and waste and their valorisation in more sustainable industrial applications. This study aims to characterise the phytochemical composition and antioxidant activity of 13 food grade tannins using multiple analytical approaches, including spectrophotometry and HPLC-ECD to determine the amount of targeted polyphenolic compounds. Moreover, the antioxidant activity of tannins was assessed in terms of radical scavenging activity (DPPH• assay), reducing power (FRAP assay), and redox properties (cyclic voltammetry, CV). A statistical univariate and multivariate correlation analysis was performed on 17 parameters including tannin content (range: 0.71-1.62 mM), gallic acid, (+)-catechin, syringic acid and (‒)-epicatechin. The compositional profile of tannins was related to their chemical moiety, antioxidant activity and the botanical origin of the extracts. In particular, the CV signal at 500 mV was highly correlated with DPPH• value due to the catechol ring of flavonoids and trigalloyl moieties of gallic acid-based compounds. Practical examples of tannins application in winemaking are discussed.

Influence of supplementation with different oenological tannins on malvidin-3-monoglucoside copigmentation

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Gombau Jordi

2016-01-01

Full Text Available The effect as copigment of (--epicatechin and five different oenological tannins has been measured in a model wine solution containing malvidine-3-monoglucoside. The results show that all oenological tannins exert a positive effect on the color of the malvidine solution, increasing the global absorptivity spectrum and changing the Cielab coordinates. Specifically, supplementation with oenological tannins increase a* and b* and decreases L*. Overall, the effect as copigments of all oenological tannins was higher than that of (−-epicatechin.

Inhibitive Behaviour of Corrosion of Aluminium Alloy in NaCl by Mangrove Tannin

International Nuclear Information System (INIS)

Solhan Yahya; Afidah Abdul Rahim; Affaizza Mohd Shah; Rohana Adnan

2011-01-01

Anticorrosion potential of mangrove tannins on aluminium alloys AA6061 in NaCl solution has been studied using potentiodynamic polarisation method and scanning electron microscopy (SEM). The study was carried out in different pH of corrosive medium in the absence and presence of various concentrations of tannin. The corrosion inhibition behaviour of the mangrove tannin on AA6061 aluminium alloy corrosion was found to be dependant on the pH of NaCl solution. Our results showed that the inhibition efficiency increased with increasing tannins concentration in chloride solution at pH 6. Treatment of aluminium alloy 6061 with all concentrations of mangrove tannins reduced the current density, thus decreased the corrosion rate. Tannins behaved as mixed inhibitors at pH 6 and reduction in current density predominantly affected in cathodic reaction. Meanwhile, at pH 12, addition of tannins shifted the corrosion potential to more cathodic potentials and a passivating effect was observed in anodic potentials. SEM studies have shown that the addition of tannins in chloride solution at pH 12 reduced the surface degradation and the formation of pits. (author)

In Vitro Ruminal Degradability of Soybean Meal Protein Protected with Natural Tannin

Science.gov (United States)

Prasetiyono, B. W. H. E.; Subrata, A.; Tampoebolon, B. I. M.; Surono; Widiyanto

2018-02-01

The influence of tannin from tea waste and gambier as natural tannin sources on ruminal protein degradability was studied in this investigation. The soybean meal was used as protein source in this investigation. There were three treatments in this investigation mainly without protection (NT); protection with tea waste (Tt); and protection with gambier (Tg). The measured parameters consisted of in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD), and the ruminal fermentation characteristics. Results of this experiment showed that protection with tannin from tea waste as well as gambier increased (pRUP) in Tt and Tg group was higher than that in NT group (66.29 and 69.20 vs 51.10%). The ruminal protozoa population decreased (pRUP. The ruminal protozoa population and ammonia concentration, on the other hand, were decreased by tannin protection from those tannin natural sources. The natural tannin from gambier was the most effective protection agent for soybean meal protein.

Analysis of Valonia Oak (Quercus aegylops Acorn Tannin and Wood Adhesives Application

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Soliman Abdalla

2015-09-01

Full Text Available The coupling of matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF mass spectrometry with 13C nuclear magnetic resonance (NMR is a suitable method for examining the composition of hydrolysable tannins and has been applied to the investigation of valonia oak (Quercus aegylops acorn tannin extract. Such methods can determine the extract’s structural aspects and other characteristics. It was determined that valonia oak acorn tannin extract is composed of mainly pentagalloylglucose structures; their rearrangement structures, vescalagin/castalagin (with linkages to flavogallonic acid and vescalin/castalin; ellagic acid and vescavaloneic/castavaloneic acid; and free gallic acid and glucose. Traces of catechin gallate were also observed in this tannin extract. The tannin from acorns of valonia oak was used to substitute up to 50% of the phenol used in the preparation of phenolic resins as adhesives for wood particleboard. These phenol-tannin-formaldehyde resins showed comparable performance to phenol-formaldehyde resins.

Understanding the Relationship between Red Wine Matrix, Tannin Activity, and Sensory Properties.

Science.gov (United States)

Watrelot, Aude A; Byrnes, Nadia K; Heymann, Hildegarde; Kennedy, James A

2016-11-30

One major red wine mouthfeel characteristic, astringency, is derived from grape-extracted tannins and is considered to be a result of interaction with salivary proteins and the oral mucosa. To improve our understanding of the role that the enthalpy of interaction of tannin with a hydrophobic surface (tannin activity) has in astringency perception, a chromatographic method was used to determine the tannin concentration and activity of 34 Cabernet Sauvignon wines, as well as sensory analysis done on 13 of those wines. In addition, astringency-relevant matrix parameters (pH, titratable acidity, ethanol, glucose, and fructose) were measured across all wines. Tannin activity was not significantly correlated with any matrix variables, and the perception of drying and grippy was not correlated with tannin concentration and activity. However, ethanol content was well related to mouthfeel attributes and appeared to drive perceived drying. Although fructose and glucose content were well correlated, they did not drive the perception of sweetness, which is explained by the well-known mixture suppression effect.

Characterization of tannin-metal complexes by UV-visible spectrophotometry

Science.gov (United States)

Tannins enter soils by plant decay and rain throughfall, but little is known of their effects on soils. Tannins may influence bioavailability and toxicity of metals by forming complexes and by mediating redox reactions. We evaluated the affinity and stoichiometry of Al(III) for a gallotannin, pent...

EKSTRAKSI TANNIN SEBAGAI BAHAN PEWARNA ALAMI DARI TANAMAN PUTRIMALU (MIMOSA PUDICA MENGGUNAKAN PELARUT ORGANIK

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Tjukup Marnoto

2012-05-01

Full Text Available EXTRACTION OF TANNINS AS NATURAL DYES FROM PUTRIMALU (MIMOSA PUDICA PLANT USING VARIOUS ORGANIC SOLVENTS. Public awareness on using natural dyes has encouraged the extraction of tannins from putrimalu. Extraction was performed continuously using a Soxhlet apparatus. The parameter studied was the influence of solvent polarity on the amount of tannin and mass transfer coefficient. Tannin was extracted from ten grams of dried putrimalu plants using polar solvents (ethanol, acetone and methanol and a non-polar solvent (n-hexane. Extraction is considered complete when the concentration of tannins in the liquid is no longer changing with time. Liquid samples were withdrawn every 20 minutes interval for tannin analyses using Thin Layer Chromatography (TLC. The results showed that the maximum concentration of tannins in the extract (g/mL when extraction were performed using n-hexane was 0.0031, acetone (0.016, methanol (0.0274 and ethanol (0.044. From extract yield and mass transfer coefficient point of views, it can be concluded that the best solvent is ethanol. The relationship between tannin concentration in the ethanol 96% solvent and the time was expressed in term of mathematical equations             CAL=1.046(1-e-0.0213t with error was 3.6%. Where CAL is the concentration of tannins in the solvent (g/ml and t is the extraction time (minutes.  Kesadaran masyarakat untuk kembali menggunakan bahan pewarna alami mendorong dilakukannya ekstraksi tannin dari putrimalu. Ekstraksi dilakukan secara kontinyu menggunakan alat Soxhlet. Parameter yang dipelajari adalah pengaruh polaritas pelarut terhadap ekstrak tannin dan koefisien transfer massa. Tannin diekstrak dari sepuluh gram tanaman putrimalu kering menggunakan pelarut polar (etanol, aseton dan metanol dan pelarut non-polar n-heksana. Ekstraksi dianggap selesai jika konsentrasi tannin di dalam pelarut sudah tidak berubah. Tannin di dalam contoh cairan yang diambil setiap selang waktu 20

Environmental control and intersite variations of phenolics in Betula nana in tundra ecosystems

DEFF Research Database (Denmark)

Graglia, Enrico; Julkunen-Tiitto, Riitta; Shaver, Gaius R.

2001-01-01

to a decade of warming, fertilization and shading. • Nitrogen and a number of phenolics, including condensed and hydrolysable tannins, flavonoids, phenolic glucosides and chlorogenic acids, were analysed in B. nana leaves. • Phenolic concentrations showed marked between-site differences (e.g. condensed...... tannins were 50% higher at Abisko than at Toolik); responses to the environmental manipulations were more pronounced at Toolik compared with Abisko. Warming increased condensed tannins and decreased hydrolysable tannins at Toolik, but had no effect at Abisko, whereas fertilization and shading generally...

Interfacial Charge Transfer States in Condensed Phase Systems

Science.gov (United States)

Vandewal, Koen

2016-05-01

Intermolecular charge transfer (CT) states at the interface between electron-donating (D) and electron-accepting (A) materials in organic thin films are characterized by absorption and emission bands within the optical gap of the interfacing materials. CT states efficiently generate charge carriers for some D-A combinations, and others show high fluorescence quantum efficiencies. These properties are exploited in organic solar cells, photodetectors, and light-emitting diodes. This review summarizes experimental and theoretical work on the electronic structure and interfacial energy landscape at condensed matter D-A interfaces. Recent findings on photogeneration and recombination of free charge carriers via CT states are discussed, and relations between CT state properties and optoelectronic device parameters are clarified.

Yeast effects on Pinot noir wine phenolics, color, and tannin composition.

Science.gov (United States)

Carew, Anna L; Smith, Paul; Close, Dugald C; Curtin, Chris; Dambergs, Robert G

2013-10-16

Extraction and stabilization of wine phenolics can be challenging for wine makers. This study examined how yeast choice affected phenolic outcomes in Pinot noir wine. Five yeast treatments were applied in replicated microvinification, and wines were analyzed by UV-visible spectrophotometry. At bottling, yeast treatment Saccharomyces cerevisiae RC212 wine had significantly higher concentrations of total pigment, free anthocyanin, nonbleachable pigment, and total tannin and showed high color density. Some phenolic effects were retained at 6 months' bottle age, and RC212 and S. cerevisae EC1118 wines showed increased mean nonbleachable pigment concentrations. Wine tannin composition analysis showed three treatments were associated with a higher percentage of trihydroxylated subunits (skin tannin indicator). A high degree of tannin polymerization was observed in wines made with RC212 and Torulaspora delbruekii , whereas tannin size by gel permeation chromatography was higher only in the RC212 wines. The results emphasize the importance of yeast strain choice for optimizing Pinot noir wine phenolics.

Relation ofSpodoptera eridania choice to tannins and protein oflotus corniculatus.

Science.gov (United States)

Briggs, M A

1990-05-01

Plant secondary compounds such as tannins may influence herbivore choice. To determine if herbivory was influenced by tannin concentration,Spodoptera eridania larvae were given a choice ofLotus corniculatus plants whose chemical profiles were altered by fertilization. Herbivores chose plants that had been grown with symbiotic nitrogen fixation as their only nitrogen source more often than fertilized plants. Choice was related to protein concentration, but not to tannin concentration.

Thermodynamics of grape and wine tannin interaction with polyproline: implications for red wine astringency.

Science.gov (United States)

McRae, Jacqui M; Falconer, Robert J; Kennedy, James A

2010-12-08

The astringency of red wine is largely due to the interaction between wine tannins and salivary proline-rich proteins and is known to change as wine ages. To further understand the mechanisms behind wine astringency change over time, thermodynamics of the interactions between poly(l-proline) (PLP) and grape seed and skin tannins (preveraison (PV) and commercially ripe) or Shiraz wine tannins (2 years old and 9-10 years old) was analyzed using isothermal titration calorimetry (ITC). The nature of these interactions varied with changes to the tannin structure that are associated with maturation. The change in enthalpy associated with hydrophobic interaction and hydrogen bonding decreased with tannin age and the stoichiometry of binding indicated that grape tannins associated with more proline residues than wine tannins, irrespective of molecular size. These results could provide an explanation for the observed change in wine astringency quality with age.

Membrane lipids protected from oxidation by red wine tannins: a proton NMR study.

Science.gov (United States)

Furlan, Aurélien L; Jobin, Marie-Lise; Buchoux, Sébastien; Grélard, Axelle; Dufourc, Erick J; Géan, Julie

2014-12-01

Dietary polyphenols widespread in vegetables and beverages like red wine and tea have been reported to possess antioxidant properties that could have positive effects on human health. In this study, we propose a new in situ and non-invasive method based on proton liquid-state nuclear magnetic resonance (NMR) to determine the antioxidant efficiency of red wine tannins on a twice-unsaturated phospholipid, 1,2-dilinoleoyl-sn-glycero-3-phosphocholine (DLiPC), embedded in a membrane model. Four tannins were studied: (+)-catechin (C), (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), and (-)-epigallocatechin gallate (EGCG). The lipid degradation kinetics was determined by measuring the loss of the bis-allylic protons during oxidation induced by a radical initiator, 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH). The antioxidant efficiency, i.e. the ability of tannins to slow down the lipid oxidation rate, was shown to be higher for galloylated tannins, ECG and EGCG. Furthermore, the mixture of four tannins was more efficient than the most effective tannin, EGCG, demonstrating a synergistic effect. To better understand the antioxidant action mechanism of polyphenols on lipid membranes, the tannin location was investigated by NMR and molecular dynamics. A correlation between antioxidant action of tannins and their location at the membrane interface (inserted at the glycerol backbone level) could thus be established. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Tannin fingerprinting in vegetable tanned leather by solid state NMR spectroscopy and comparison with leathers tanned by other processes.

Science.gov (United States)

Romer, Frederik H; Underwood, Andrew P; Senekal, Nadine D; Bonnet, Susan L; Duer, Melinda J; Reid, David G; van der Westhuizen, Jan H

2011-01-28

Solid state ¹³C-NMR spectra of pure tannin powders from four different sources--mimosa, quebracho, chestnut and tara--are readily distinguishable from each other, both in pure commercial powder form, and in leather which they have been used to tan. Groups of signals indicative of the source, and type (condensed vs. hydrolyzable) of tannin used in the manufacture are well resolved in the spectra of the finished leathers. These fingerprints are compared with those arising from leathers tanned with other common tanning agents. Paramagnetic chromium (III) tanning causes widespread but selective disappearance of signals from the spectrum of leather collagen, including resonances from acidic aspartyl and glutamyl residues, likely bound to Cr (III) structures. Aluminium (III) and glutaraldehyde tanning both cause considerable leather collagen signal sharpening suggesting some increase in molecular structural ordering. The ²⁷Al-NMR signal from the former material is consistent with an octahedral coordination by oxygen ligands. Solid state NMR thus provides easily recognisable reagent specific spectral fingerprints of the products of vegetable and some other common tanning processes. Because spectra are related to molecular properties, NMR is potentially a powerful tool in leather process enhancement and quality or provenance assurance.

The Effect of Tannins and Additional Peg on In Vitro Gas Production

International Nuclear Information System (INIS)

Irawan Sugoro

2004-01-01

Agro-wastes such as sugar cane straw are potential sources as feed. Sugar cane straw contains tannins, an anti-nutrient, which could effect feed quality. The effect of tannins by in vitro gas production was compared to maize straw which has low tannins. Tannin concentration was measured by using PEG which is labelled by 14 C. The result showed that the tannins concentration of sugar cane straw is 10.88 % dry matter. The others are digestibility of dry matter and organic matter, VFA, ammonia and pH. The gas production is 48.83 ml/500 mg after 24 h incubation. It is lower than the control i.e. 100.64 ml/500 mg. Additional PEG increase the gas production i.e. 30.5 %, because tannins is bounded by it. The concentration of ammonia, VFA, dry matter and organic matter digestibility on sugar cane straw with additional PEG is higher than without PEG, i.e 28.29 mg/100 ml, 15.56 nmol/100 ml, 52.18 % and 47.54 %. pH of sugar cane without PEG i.e. 6.62 is higher than additional PEG, i.e. 6.54. It could be concluded, tannins decrease of gas production, ammonia, VFA, dry matter, and organic matter digestibility and additional PEG increase gas production of sugar cane. (author)

Chelation of Cu(II, Zn(II, and Fe(II by Tannin Constituents of Selected Edible Nuts

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Magdalena Karamać

2009-12-01

Full Text Available The tannin fractions isolated from hazelnuts, walnuts and almonds were characterised by colorimetric assays and by an SE-HPLC technique. The complexation of Cu(II and Zn(II was determined by the reaction with tetramethylmurexide, whereas for Fe(II, ferrozine was employed. The walnut tannins exhibited a significantly weaker reaction with the vanillin/HCl reagent than hazelnut and almond tannins, but the protein precipitation capacity of the walnut fraction was high. The SE-HPLC chromatogram of the tannin fraction from hazelnuts revealed the presence of oligomers with higher molecular weights compared to that of almonds. Copper ions were most effectively chelated by the constituents of the tannin fractions of hazelnuts, walnuts and almonds. At a 0.2 mg/assay addition level, the walnut tannins complexed almost 100% Cu(II. The Fe(II complexation capacities of the tannin fractions of walnuts and hazelnuts were weaker in comparison to that of the almond tannin fraction, which at a 2.5 mg/assay addition level, bound Fe(II by ~90%. The capacity to chelate Zn(II was quite varied for the different nut tannin fractions: almond tannins bound as much as 84% Zn(II, whereas the value for walnut tannins was only 8.7%; and for hazelnut tannins, no Zn(II chelation took place at the levels tested.

Analysis and Testing of Bisphenol A-Free Bio-Based Tannin Epoxy-Acrylic Adhesives

OpenAIRE

Jahanshahi , Shayesteh; Pizzi , Antonio; Abdulkhani , Ali; Shakeri , Alireza

2016-01-01

International audience; A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET) and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, C-13-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 degrees C for 12 h. FT-MIR, C-13...

Tannin profile of different Monastrell wines and its relation to projected market prices.

Science.gov (United States)

Gómez-Plaza, Encarna; Olmos, Oscar; Bautista-Ortín, Ana Belén

2016-08-01

This study focuses on the differences or similarities in tannin composition and concentration in Monastrell wines from different wineries from the same geographic area and, within each winery, from wines elaborated based on different projected market prices, to determine whether there is any relationship between the wine tannin composition and the projected price. The tannin composition of the different wines, all of them analyzed at the same point during winemaking, indicated that those elaborated as premium wines presented higher phenol and tannin contents. The mean degree of polymerization of these wines was also positively related with the projected price, which agreed with the results obtained by size exclusion chromatography, that showed that wines with high projected prices had a higher proportion of polymeric tannins, suggesting that techniques favoring the extraction of skin tannins were mostly used in those wines projected as premium wines, probably looking for greater mouthfeel complexity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interactions between grape skin cell wall material and commercial enological tannins. Practical implications.

Science.gov (United States)

Bautista-Ortín, Ana Belén; Cano-Lechuga, Mario; Ruiz-García, Yolanda; Gómez-Plaza, Encarna

2014-01-01

Commercial enological tannins were used to investigate the role that cell wall material plays in proanthocyanidin adsorption. Insoluble cell wall material, prepared from the skin of Vitis vinifera L. cv. Monastrell berries, was combined with solutions containing six different commercial enological tannins (proanthocyanidin-type tannins). Analysis of the proanthocyanidins in the solution, after fining with cell wall material, using phloroglucinolysis and size exclusion chromatography, provided quantitative and qualitative information on the non-adsorbed compounds. Cell wall material showed strong affinity for the proanthocyanidins, one of the commercial tannins being bound up to 61% in the experiment. Comparison of the molecular mass distribution of the commercial enological tannins in solution, before and after fining, suggested that cell walls affinity for proanthocyanidins was more related with the proanthocyanidin molecular mass than with their percentage of galloylation. These interactions may have some enological implications, especially as regards the time of commercial tannins addition to the must/wine. Copyright © 2013 Elsevier Ltd. All rights reserved.

Relationship between red wine grade and phenolics. 2. Tannin composition and size.

Science.gov (United States)

Kassara, Stella; Kennedy, James A

2011-08-10

Commercial red wines ( Vitis vinifera L. cv. Shiraz) produced during the 2009 vintage underwent winemaker assessment for allocation grade soon after production. The wines were then subjected to phenolic analysis to measure wine color (total anthocyanin, SO(2) nonbleachable pigment, and wine color density) and tannins (concentration, composition, and average degree of polymerization). A positive relationship was found between wine phenolic concentration and projected bottle price. Tannin compositional analysis suggested that there was specifically a relationship between wine grade and skin-derived tannins. These results suggest that maximization of skin tannin concentration and/or proportion is related to an increase in projected wine bottle price.

Anti-inflammatory Hydrolyzable Tannins from Myricaria bracteata.

Science.gov (United States)

Liu, Jia-Bao; Ding, Ya-Si; Zhang, Ying; Chen, Jia-Bao; Cui, Bao-Song; Bai, Jin-Ye; Lin, Ming-Bao; Hou, Qi; Zhang, Pei-Cheng; Li, Shuai

2015-05-22

Twelve hydrolyzable tannins were obtained from the twigs of Myricaria bracteata, including two new hellinoyl-type dimers, bracteatinins D1 (1) and D2 (2); a new hellinoyl-type trimer, bracteatinin T1 (3); two known monomers, nilotinin M4 (4) and 1,3-di-O-galloyl-4,6-O-(aS)-hexahydroxydiphenoyl-β-d-glucose (5); six known dimers, tamarixinin A (6), nilotinin D8 (7), hirtellins A (10), B (9), and E (8), and isohirtellin C (11); and a known trimer, hirtellin T3 (12). The structures of the tannins were elucidated by spectroscopic data analysis and comparisons to known tannins. All compounds were evaluated as free radical scavengers using 1,1-diphenyl-2-picrylhydrazyl and hydroxy radicals and compared to the activity of BHT and Trolox. Compound 6 showed a significant anti-inflammatory effect on croton oil-induced ear edema in mice (200 mg/kg, inhibition rate 69.8%) and on collagen-induced arthritis in DBA/1 mice (20 mg/kg, inhibition rate 46.0% at day 57).

Study of Tannin- degrading bacteria isolated from Pistachio soft hulls and feces of goat feeding on it

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Arezoo Tahmourespour

2017-01-01

Full Text Available Introduction: Tannins (tannic acid are toxic, high molecular weight and water- soluble polyphenols that are present in many plants such as pistachio and its by- products. Wide ranges of microorganisms including bacteria tolerate tannin and degrade it. The aim of this study was to isolate and characterize tannin- tolerant bacteria from pistachio soft hulls (P- SH and feces of goat before and after feeding on this by- product as tannin rich diet. Materials and methods: Tannin tolerant bacteria were isolated from enrichment cultures of samples in medium containing tannic acid as a sole source of carbon and energy. Tannin hydrolyzing ability of isolates was confirmed by observation of clear zones around the colonies. The increasing concentrations of tannin on minimal salt medium (MSM agar plates were used to test the maximum tolerable concentrations (MTCs. Furthermore, in the supplemented media tannin concentrations were measured by bovine serum albumin (BSA precipitation assay during time intervals. Results: Tannin- degrading bacterial population of P- SH was about only 10.3% of total population. More than 50 percent of tannin degrading strains were isolated from goat feces after grazing on tannin rich diet. Isolated bacteria were Gram- negative and positive rod species belonging to Klebsiella, Pseudomonas, Bacillus, Escherichia and Enterobacter genera. Among the isolated bacteria 71.4% could tolerate the concentration of 64 g/l of tannin in their media while only 7.2% were able to tolerate the maximum tannin concentration of 16 g/l. Bacterial isolates of goat feces could degrade tannin more than 72% after 72 h of incubation. In the case of soft P- SH isolates, the biodegradation percentage was between 17- 75%. Discussion and conclusion: Feeding of tannin rich diet induced a shift in digestive system microbial profile with increased population of tannin tolerant bacteria. The ability of isolated strains provides novel insights for the role they can

Curing Characterisation of Spruce Tannin-based Foams using the Advanced Isoconversional Method

Directory of Open Access Journals (Sweden)

Matjaž Čop

2014-06-01

Full Text Available The curing kinetics of foam prepared from the tannin of spruce tree bark was investigated using differential scanning calorimetry (DSC and the advanced isoconversional method. An analysis of the formulations with differing amounts of components (furfuryl alcohol, glycerol, tannin, and a catalyst showed that curing was delayed with increasing proportions of glycerol or tannins. An optimum amount of the catalyst constituent was also found during the study. The curing of the foam system was accelerated with increasing temperatures. Finally, the advanced isoconversional method, based on the model-free kinetic algorithm developed by Vyazovkin, appeared to be an appropriate model for the characterisation of the curing kinetics of tannin-based foams.

Novel Strategies for Upstream and Downstream Processing of Tannin Acyl Hydrolase

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Luis V. Rodríguez-Durán

2011-01-01

Full Text Available Tannin acyl hydrolase also referred as tannase is an enzyme with important applications in several science and technology fields. Due to its hydrolytic and synthetic properties, tannase could be used to reduce the negative effects of tannins in beverages, food, feed, and tannery effluents, for the production of gallic acid from tannin-rich materials, the elucidation of tannin structure, and the synthesis of gallic acid esters in nonaqueous media. However, industrial applications of tannase are still very limited due to its high production cost. Thus, there is a growing interest in the production, recovery, and purification of this enzyme. Recently, there have been published a number of papers on the improvement of upstream and downstream processing of the enzyme. These papers dealt with the search for new tannase producing microorganisms, the application of novel fermentation systems, optimization of culture conditions, the production of the enzyme by recombinant microorganism, and the design of efficient protocols for tannase recovery and purification. The present work reviews the state of the art of basic and biotechnological aspects of tannin acyl hydrolase, focusing on the recent advances in the upstream and downstream processing of the enzyme.

Novel strategies for upstream and downstream processing of tannin acyl hydrolase.

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Rodríguez-Durán, Luis V; Valdivia-Urdiales, Blanca; Contreras-Esquivel, Juan C; Rodríguez-Herrera, Raúl; Aguilar, Cristóbal N

2011-01-01

Tannin acyl hydrolase also referred as tannase is an enzyme with important applications in several science and technology fields. Due to its hydrolytic and synthetic properties, tannase could be used to reduce the negative effects of tannins in beverages, food, feed, and tannery effluents, for the production of gallic acid from tannin-rich materials, the elucidation of tannin structure, and the synthesis of gallic acid esters in nonaqueous media. However, industrial applications of tannase are still very limited due to its high production cost. Thus, there is a growing interest in the production, recovery, and purification of this enzyme. Recently, there have been published a number of papers on the improvement of upstream and downstream processing of the enzyme. These papers dealt with the search for new tannase producing microorganisms, the application of novel fermentation systems, optimization of culture conditions, the production of the enzyme by recombinant microorganism, and the design of efficient protocols for tannase recovery and purification. The present work reviews the state of the art of basic and biotechnological aspects of tannin acyl hydrolase, focusing on the recent advances in the upstream and downstream processing of the enzyme.

Effects of Quebracho Tannin on Recovery of Colloidal Gold from ...

African Journals Online (AJOL)

This paper considered effects of Quebracho Tannin (QT) on recovery of gold from the oxidized flotation concentrate wash liquor. The effect of Quebracho Tannin on Total Suspended Solids (TSS) was also established. This research established that the gold lost to tailings was not soluble in the effluent but was mainly in the ...

Effect of wine pH and bottle closure on tannins.

Science.gov (United States)

McRae, Jacqui M; Kassara, Stella; Kennedy, James A; Waters, Elizabeth J; Smith, Paul A

2013-11-27

The impact of wine pH and closure type on color, tannin concentration, and composition was investigated. A single vintage of Cabernet Sauvignon wine was divided into three batches, the pH was adjusted to 3.2, 3.5 or 3.8, and the wines were bottled under screw caps with either SaranTin (ST) or Saranex (Sx) liners. After 24 months, the tannin concentration, tannin percent yield (relating to the proportion of acid-labile interflavan bonds), and the mean degree of polymerization (mDp) had decreased significantly, all of which can contribute to the softening of wine astringency with aging. The higher pH wines contained less percent (-)-epicatechin 3-O-gallate subunits, whereas the Sx pH 3.2 wines were significantly lower in percent yield and mDp than the other wines. Overall, the tannin structure and wine color of the lower pH wines (pH 3.2) bottled under Sx screw caps changed more rapidly with aging than those of the higher pH wines (pH 3.8) bottled under ST screw caps.

CHROMIUM (III ADSORPTION FROM AQUEOUS SOLUTION BY Rhizophora apiculata TANNINS

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C. W. Oo

2010-06-01

Full Text Available Adsorption of Cr3+ from aqueous solution by Rhizophora apiculata tannins was investigated in batch shaking experiments. Tannins extracted from R. apiculata mangrove barks was chemically modified with formaldehyde in the basic solution of sodium hydroxide. The performance of the produced adsorbent on the adsorption of Cr3+ was evaluated based on the effect of several parameters like initial pH, adsorbent dosage, initial Cr3+ concentration and contact time. Equilibrium adsorption data was analyzed by Langmuir, Freundlich, Sips and Dubinin-Raduskhevich (D-R isotherms. The fitness of the isotherms to the experimental data was determined by non-linear regression analysis. Adsorption capacity calculated from Langmuir isotherm was found to be 10.14 mg Cr3+/g of adsorbent at optimum adsorption pH of 4.5. Mean energy of adsorption with the value of 10.35 kJ/mol indicated that adsorption Cr3+ on Rhizophora apiculata tannins followed ion-exchange reaction. Kinetic study showed that the adsorption process followed the pseudo second-order kinetic model.   Keywords:  Rhizophora apiculata, tannins, isotherms, kinetic, chromium.

Visual and colorimetric methods for rapid determination of total tannins in vegetable raw materials

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S. P. Kalinkina

2016-01-01

Full Text Available The article is dedicated to the development of rapid colorimetric method for determining the amount of tannins in aqueous extracts of vegetable raw materials. The sorption-based colorimetric test is determining sorption tannins polyurethane foam, impregnated of FeCl3, receiving on its surface painted in black and green color of the reaction products and the determination of their in sorbent matrix. Selectivity is achieved by determining the tannins specific interaction of polyphenols with iron ions (III. The conditions of sorption-colorimetric method: the concentration of ferric chloride (III, impregnated in the polyurethane foam; sorbent mass in the analytical cartridge; degree of loading his agent; the contact time of the phases. color scales have been developed for the visual determination of the amount of tannins in terms of gallic acid. Spend a digitized image obtained scales using computer program “Sorbfil TLC”, excluding a subjective assessment of the intensity of the color scale of the test. The results obtained determine the amount of tannins in aqueous extracts of vegetable raw rapid method using tablets and analytical cartridges. The results of the test determination of tannins with visual and densitometric analytical signal registration are compared to known methods. Spend a metrological evaluation of the results of determining the amount of tannins sorption rapid colorimetric methods. Time visual and densitometric rapid determination of tannins, taking into account the sample preparation is 25–30 minutes, the relative error does not exceed 28 %. The developed test methods for quantifying the content of tannins allow to exclude the use of sophisticated analytical equipment, carry out the analysis in non-laboratory conditions do not require highly skilled personnel.

TANNIN POTENCIAL EVALUATION OF SIX FOREST SPECIES OF BRAZILIAN SEMI-ARID REGION

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Juarez Benigno Paes

2006-09-01

Full Text Available The hide tanners of Brazil Northeast region have in Anadenanthera colubrina (Vell. Brenan var. cebil (Gris. Alts. their only source of tannins. As the activity of exploration is extractiviste without the concern of recovery of explored trees and the absence of other tannin sources, exposes the specie to exhaustion and the tanners and extractivistes family to go bankruptcy. Thus, this work aimed to evaluate the tanin potential of Prosopis juliflora, Anadenanthera colubrina var. cebil, Anacardium occidentale, Mimosa tenuiflora, Mimosa arenosa and Croton sonderianus. These species, Anacardium occidentale, Mimosa arenosa and Mimosa temuiflora showed, respectively, 19.83%, 18.11% and 17.74% of tannins. The Anadenanthera colubrina showed 11.89% and was inferior them mentioned species. The Prosopis juliflora and Croton sonderianus showed 3.02% and 6.62%, respectively. The abundance of Mimosa arenosa and Mimosa tenuiflora in the Brazilian Semi-arid proposes them as potential of tannin production. However, there is need of researches to verify their technical viability for skins, as well as for other uses for tannins.

Lamb meat colour stability as affected by dietary tannins

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Pietro Pennisi

2010-01-01

Full Text Available Twenty-one male Comisana lambs were divided into three groups at 45 days of age and were individually penned for 60 days. Seven lambs were fed a concentrate-based diet (C, seven lambs received the same concentrate with the addiction of tannins from quebracho (Schinopsis lorentzii; T, whereas the remaining animals were fed exclusively fresh vetch (Vicia sativa; H. Colour descriptors (a*, b* and H* and metmyoglobin (MMb percentages were measured on minced semimembranosus muscle over 14 days of refrigerated storage in a high oxygen atmosphere. Regardless of dietary treatment, meat redness decreased, while yellowness and hue angle increased (P < 0.001 over storage duration. However, higher a* values, lower b* values and lower H* values were observed in meat from both H- and T-fed animals as compared to meat from C-fed lambs (P = 0.012; P = 0.02; P = 0.003, respectively. Metmyoglobin formation increased over time (P < 0.001, but H diet resulted in lower metmyoglobin percentages than C diet (P = 0.007. We conclude that the inclusion of tannins into the concentrate improved meat colour stability compared to a tannin-free concentrate. Moreover, the protective effect of tannins against meat discolouration was comparable to that obtained by feeding lambs fresh herbage.

How to gain insight into the polydispersity of tannins: a combined MS and LC study.

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Mouls, Laetitia; Hugouvieux, Virginie; Mazauric, Jean-Paul; Sommerer, Nicolas; Mazerolles, Gérard; Fulcrand, Hélène

2014-12-15

In the context of the potential health benefits of food polyphenols, the bioavailability of tannins (i.e. proanthocyanidins) is a major issue, which is strongly influenced by the polydispersity and the degree of polymerisation of tannins. The average degree of polymerisation (DP) of tannins is usually determined using depolymerisation methods, which do not provide any information about their polymer distribution. Moreover, it is still a challenge to characterise tannin fractions of high polydispersity and/or containing polymers of high molecular weights, due to the limit of detection of direct mass spectrometry (MS) analysis methods. In the present work, the polydispersity of several tannin fractions is investigated by two complementary methods: a MALDI-MS method and a semi-preparative sub-fractionation. Using a combination of these methods we are able to gain insight into the DP distributions of the fractions consisting of tannins of medium and high DP. Moreover combining analyses can be useful to assess and compare the DP distributions of most tannin fractions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Botanical traceability of commercial tannins using the mineral profile and stable isotopes.

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Bertoldi, Daniela; Santato, Alessandro; Paolini, Mauro; Barbero, Alice; Camin, Federica; Nicolini, Giorgio; Larcher, Roberto

2014-09-01

Commercial tannins are natural polyphenolic compounds extracted from different plant tissues such as gall, the wood of different species and fruit. In the food industry they are mainly used as flavourings and food ingredients, whereas in winemaking they are classified as clarification agents for wine protein stabilisation, although colour stabilisation, metal removal, unpleasant thiol removal and rheological correction are also well-known and desired effects. Due to their particular technical properties and very different costs, the possibility of correct identification of the real botanical origin of tannins can be considered a primary target in oenology research and in fulfilling the technical and economic requirements of the wine industry. For some categories of tannins encouraging results have already been achieved by considering sugar or polyphenolic composition. For the first time this work verifies the possibility of determining the botanical origin of tannins on the basis of the mineral element profile and analysis of the (13) C/(12) C isotopic ratio. One hundred two commercial tannins originating from 10 different botanical sources (grapes, oak, gall, chestnut, fruit trees, quebracho, tea, acacia, officinal plants and tara) were analysed to determine 57 elements and the (13) C/(12) C isotopic ratio, using inductively coupled plasma mass spectrometry and isotope-ratio mass spectrometry, respectively. Forward stepwise discriminant analysis provided good discrimination between the 8 most abundant groups, with 100% correct re-classification. The model was then validated five times on subsets of 10% of the overall samples, randomly extracted, achieving satisfactory results. With a similar approach it was also possible to distinguish toasted and untoasted oak tannins as well as tannins from grape skin and grape seeds. Copyright © 2014 John Wiley & Sons, Ltd.

Tannin Fingerprinting in Vegetable Tanned Leather by Solid State NMR Spectroscopy and Comparison with Leathers Tanned by Other Processes

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Jan H. van der Westhuizen

2011-01-01

Full Text Available Solid state 13C-NMR spectra of pure tannin powders from four different sources – mimosa, quebracho, chestnut and tara – are readily distinguishable from each other, both in pure commercial powder form, and in leather which they have been used to tan.  Groups of signals indicative of the source, and type (condensed vs. hydrolyzable of tannin used in the manufacture are well resolved in the spectra of the finished leathers.  These fingerprints are compared with those arising from leathers tanned with other common tanning agents.  Paramagnetic chromium (III tanning causes widespread but selective disappearance of signals from the spectrum of leather collagen, including resonances from acidic aspartyl and glutamyl residues, likely bound to Cr (III structures. Aluminium (III and glutaraldehyde tanning both cause considerable leather collagen signal sharpening suggesting some increase in molecular structural ordering. The 27Al-NMR signal from the former material is consistent with an octahedral coordination by oxygen ligands. Solid state NMR thus provides easily recognisable reagent specific spectral fingerprints of the products of vegetable and some other common tanning processes. Because spectra are related to molecular properties, NMR is potentially a powerful tool in leather process enhancement and quality or provenance assurance.

Analysis of supercooling activity of tannin-related polyphenols.

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Kuwabara, Chikako; Wang, Donghui; Endoh, Keita; Fukushi, Yukiharu; Arakawa, Keita; Fujikawa, Seizo

2013-08-01

Based on the discovery of novel supercooling-promoting hydrolyzable gallotannins from deep supercooling xylem parenchyma cells (XPCs) in Katsura tree (see Wang et al. (2012) [38]), supercooling capability of a wide variety of tannin-related polyphenols (TRPs) was examined in order to find more effective supercooling-promoting substances for their applications. The TRPs examined were single compounds including six kinds of hydrolyzable tannins, 11 kinds of catechin derivatives, two kinds of structural analogs of catechin and six kinds of phenolcarboxylic acid derivatives, 11 kinds of polyphenol mixtures and five kinds of crude plant tannin extracts. The effects of these TRPs on freezing were examined by droplet freezing assays using various solutions containing different kinds of identified ice nucleators such as the ice nucleation bacterium (INB) Erwinia ananas, the INB Xanthomonas campestris, silver iodide and phloroglucinol as well as a solution containing only unintentionally included unidentified airborne ice nucleators. Among the 41 kinds of TRPs examined, all of the hydrolyzable tannins, catechin derivatives, polyphenol mixtures and crude plant tannin extracts as well as a few structural analogs of catechin and phenolcarboxylic acid derivatives exhibited supercooling-promoting activity (SCA) with significant differences (p>0.05) from at least one of the solutions containing different kinds of ice nucleators. It should be noted that there were no TRPs exhibiting ice nucleation-enhancing activity (INA) in all solutions containing identified ice nucleators, whereas there were many TRPs exhibiting INA with significant differences in solutions containing unidentified ice nucleators alone. An emulsion freezing assay confirmed that these TRPs did not essentially affect homogeneous ice nucleation temperatures. It is thought that not only SCA but also INA in the TRPs are produced by interactions with heterogeneous ice nucleators, not by direct interaction with water

Pre-fermentation addition of grape tannin increases the varietal thiols content in wine.

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Larcher, Roberto; Tonidandel, Loris; Román Villegas, Tomás; Nardin, Tiziana; Fedrizzi, Bruno; Nicolini, Giorgio

2015-01-01

The recent finding that grape tannin may contain significant amount of S-glutathionylated (GSH-3MH) and S-cysteinylated (Cys-3MH) precursors of the varietal thiols 3-mercapto-1-hexanol and 3-mercaptohexyl acetate, characteristic of Sauvignon blanc wines, offers new opportunities for enhancing the tropical aroma in fermented beverages. In this study this new hypothesis was investigated: Müller Thurgau (17 samples) and Sauvignon blanc (15 samples) grapes were fermented with and without addition of a selected grape tannin. As expected, the tannin-added juices were higher in precursors, and they produced wines with increased free thiols. Preliminary informal sensory tests confirmed that in particular the Sauvignon wines produced with the tannin addition were often richer with increased "fruity/green" notes than the corresponding reference wines. This outcome confirms that grape tannin addition prior to fermentation can fortify the level of these compounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

Salivary proline-rich protein may reduce tannin-iron chelation: a systematic narrative review

OpenAIRE

Delimont, Nicole M.; Rosenkranz, Sara K.; Haub, Mark D.; Lindshield, Brian L.

2017-01-01

Background Tannins are often cited for antinutritional effects, including chelation of non-heme iron. Despite this, studies exploring non-heme iron bioavailability inhibition with long-term consumption have reported mixed results. Salivary proline-rich proteins (PRPs) may mediate tannin-antinutritional effects on non-heme iron bioavailability. Aim To review evidence regarding biochemical binding mechanisms and affinity states between PRPs and tannins, as well as effects of PRPs on non-heme ir...

Relationship between red wine grades and phenolics. 1. Tannin and total phenolics concentrations.

Science.gov (United States)

Mercurio, Meagan D; Dambergs, Robert G; Cozzolino, Daniel; Herderich, Markus J; Smith, Paul A

2010-12-08

Measuring chemical composition is a common approach to support decisions about allocating foods and beverages to grades related to market value. Red wine is a particularly complex beverage, and multiple compositional attributes are needed to account for its sensory properties, including measurement of key phenolic components such as anthocyanins, total phenolics, and tannin, which are related to color and astringency. Color has been shown to relate positively to red wine grade; however, little research has been presented that explores the relationship between astringency-related components such as total phenolic or tannin concentration and wine grade. The aim of this research has been to investigate the relationship between the wine grade allocations of commercial wineries and total phenolic and tannin concentrations, respectively, in Australian Shiraz and Cabernet Sauvignon wines. Total phenolic and tannin concentrations were determined using the methyl cellulose precipitable (MCP) tannin assay and then compared to wine grade allocations made by winemaker panels during the companies' postvintage allocation process. Data were collected from wines produced by one Australian wine company over the 2005, 2006, and 2007 vintages and by a further two companies in 2007 (total wines = 1643). Statistical analysis revealed a positive trend toward higher wine grade allocation and wines that had higher concentrations of both total phenolics and tannin, respectively. This research demonstrates that for these companies, in general, Cabernet Sauvignon and Shiraz wines allocated to higher market value grades have higher total phenolics and higher tannin concentrations and suggests that these compositional parameters should be considered in the development of future multiparameter decision support systems for relevant commercial red wine grading processes. In addition, both tannin and total phenolics would ideally be included because although, in general, a positive relationship

Ethanol Concentration Influences the Mechanisms of Wine Tannin Interactions with Poly(L-proline) in Model Wine.

Science.gov (United States)

McRae, Jacqui M; Ziora, Zyta M; Kassara, Stella; Cooper, Matthew A; Smith, Paul A

2015-05-06

Changes in ethanol concentration influence red wine astringency, and yet the effect of ethanol on wine tannin-salivary protein interactions is not well understood. Isothermal titration calorimetry (ITC) was used to measure the binding strength between the model salivary protein, poly(L-proline) (PLP) and a range of wine tannins (tannin fractions from a 3- and a 7-year old Cabernet Sauvignon wine) across different ethanol concentrations (5, 10, 15, and 40% v/v). Tannin-PLP interactions were stronger at 5% ethanol than at 40% ethanol. The mechanism of interaction changed for most tannin samples across the wine-like ethanol range (10-15%) from a combination of hydrophobic and hydrogen binding at 10% ethanol to only hydrogen binding at 15% ethanol. These results indicate that ethanol concentration can influence the mechanisms of wine tannin-protein interactions and that the previously reported decrease in wine astringency with increasing alcohol may, in part, relate to a decrease tannin-protein interaction strength.

Radioisotope method for characterization of vegetable tannins, extracted from waste of forestry production in Cuba

International Nuclear Information System (INIS)

Santana Romero, J.L.; Martinez Luzardo, F.; Codorniu Hernandez, E.; Vargas Guerra, L.; Melo Cala, P.; Garcia Guillen, M.; Isaac Olive, K.; Estevez, P.; Roque Cordoba, A.; Benitez, M.

2002-01-01

Vegetable tannins are polyphenolic plants secondary metabolites, widely distributed in all parts of trees and herbs. The role of these substances in many metabolic processes is very important. Vegetable tannins have been implicated as probable antinutritional factors, decreasing the assimilation of diet protein assimilation by cattle. On the other hand, protective antioxidant and antimutagenic properties have been ascribed for these compounds. Characterization of vegetable tannins is important in order to find new sources of natural raw materials with medical and pharmaceutical applications. Protein precipitation capacity as a function of pH, competitive protein and ADN binding assays and the determination of tannins concentration are described. Radioisotope labeled protein and tannins were used in all of the determinations. (author)

Calibration and validation of the 14C-labelled polyethylene glycol-binding assay for tannins in tropical browse

International Nuclear Information System (INIS)

Mlambo, V.; Makkar, H.P.S.

2005-01-01

This study evaluates the radiolabelled polyethylene glycol (PEG)-binding procedure [Silanikove, N., Shinder, D., Gilboa, N., Eyal, M., Nitsan, Z., 1996. Polyethylene glycol-binding to plant samples as an assay for the biological effects of tannins: predicting the negative effects of tannins in Mediterranean browse on rumen degradation. J. Agric. Food Chem. 44, 3230-3234] for tannin analysis, using 27 tropical browse plants. In this method, the amount of PEG bound to a plant sample is assumed to be a reflection of its tannin content. The method was modified to exclude the use of non-tanniniferous substrate for estimating non-specific binding (NSB) in tannin-containing substrates. Non-specific binding values varied widely (0.4-2.8 mg PEG/100 mg DM tannin-free substrate) when the tannin-free substrate was changed from wheat straw to either rye grass or maize shoots. We therefore propose a modified radiolabelled PEG-binding method to estimate the level of PEG-binding (PEGb) to tannin-containing foliage without using tannin-free substrate to correct for non-specific binding. In this approach, incremental levels of each tanniniferous substrate were used to generate PEGb values. The resultant linear response was analysed and tannin activity was expressed as the slope of the response curve (PEGbSlope) observed for each substrate. The slope takes into account the non-specific binding in each substrate, thus PEGbSlope does not require correction for NSB using tannin-free samples. This approach improved the correlation between PEGb and the 125 I-labelled bovine serum albumin precipitation assay. Relationships between the modified PEG-binding assay and radiolabelled bovine serum albumin assay, in vitro tannin bioassay and colorimetric assays are presented. (author)

Use of tannins to improve fatty acids profile of meat and milk quality in ruminants: A review

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Rodrigo Morales

2015-06-01

Full Text Available This paper reviews how tannins, through their effects on rumen lipid metabolism, can affect the composition of ruminants' meat and milk fat. Tannins are a heterogeneous group of plant secondary compounds known for both beneficial and detrimental effects on animals' digestive physiology. Tannins supplementation of ruminants' diets alters both in vivo and in vitro unsaturated fatty acids biohydrogenation and hence the profile of fatty acids outflowing the rumen, which can influence milk and meat content of beneficial fatty acids such as linolenic acid (c9,c12,c15-18:3, vaccenic acid (ti 1-18:1 and rumenic acid (c9,t11-18:2, among others. Published information indicates that tannins could inhibit biohydrogenation though affecting ruminal microorganisms. Some studies found increments in linolenic, rumenic and/or vaccenic acids in meat and milk fat using different sources of tannins; however, the effects of tannins supplementation on milk and meat fatty acid profile are not consistent, and there are contradictory results published in the literature. Effects of tannin supplementation on fatty acids biohydrogenation are affected by the chemical type of tannins, the complexity of their interactions with dietary components, and the potential microbial adaptation to tannins. In addition, the duration of the tannins-feeding period may also affect milk and meat fatty acid profile. Characterizing the effects of each specific tannic compound on different biohydrogenation steps and on the microbial species conducting them, as well as the interaction between specific tannin compounds and other dietary components can help to take greater advantage of tannins potential to contribute to improve human health through promoting beneficial fatty acids in ruminants products.

Green synthesis of silver nanoparticles using tannins

Science.gov (United States)

Raja, Pandian Bothi; Rahim, Afidah Abdul; Qureshi, Ahmad Kaleem; Awang, Khalijah

2014-09-01

Colloidal silver nanoparticles were prepared by rapid green synthesis using different tannin sources as reducing agent viz. chestnut (CN), mangrove (MG) and quebracho (QB). The aqueous silver ions when exposed to CN, MG and QB tannins were reduced which resulted in formation of silver nanoparticles. The resultant silver nanoparticles were characterized using UV-Visible, X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), and transmission electron microscopy (TEM) techniques. Furthermore, the possible mechanism of nanoparticles synthesis was also derived using FT-IR analysis. Spectroscopy analysis revealed that the synthesized nanoparticles were within 30 to 75 nm in size, while XRD results showed that nanoparticles formed were crystalline with face centered cubic geometry.

Effect of early experience and adaptation period on voluntary intake, digestion, and growth in Barbarine lambs given tannin-containing (Acacia cyanophylla Lindl. foliage) or tannin-free (oaten hay) diets

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Nefzaouia, A.; Ben Salem, I. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna (Austria); Hochlef, H. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia); Ben Salem, L. [Office de l' Elevage et des Paturages, Tunis (Tunisia)

2005-08-19

Our objective was to determine whether experience early in life and adaptation time (up to 72 days) to tannin-rich diets affect feed intake, digestion, nitrogen balance, and growth in Barbarine lambs given tannin-containing (Acacia cyanophylla Lindl., acacia) or tannin-free (oaten hay) diets later in life. Twelve experienced lambs (live-weight, LW: 13.2 {+-} 2.0 kg) were divided into two equal groups. Each group received air-dried acacia (tannin-containing diet) or oaten hay (hay, tannin free-diet) ad libitum. Twelve other inexperienced lambs (LW 12.3 {+-} 2.5 kg) were also divided into two equal groups. Each group received one of the above two diets. All animals were 4 months old at the start of this experiment and were supplemented with 300 g concentrate. To investigate the carry-over effect of tannins, the acacia-diet was removed on day 73, thus all lambs received thereafter the hay-diet for a further 24 days before starting a 6-day faecal collection period. Irrespective to early experience and adaptation time, the nutritive value of hay-diet was higher than that of acacia-diet and consequently lambs given hay performed better than those receiving acacia (P = 0.0001). Animals exposed to tannins early in life exhibited higher digestible crude protein intake (P = 0.0389), retained more N (P = 0.0963) and excreted more allantoin in urine (P = 0.0248) than the inexperienced lambs. Except plasma urea (P = 0.2923), the adaptation period to experimental diets affected significantly all measured parameters (P 0.0001). Animals adapted to diets for only 6 days exhibited the lowest acacia or hay intake and the highest diet digestibility compared to those adapted to these diets for 24, 48 or 72 days. Weight losses of inexperienced lambs adapted to acacia-diet for 6 days were associated with negative nitrogen balance. Sheep which received the acacia-diet, followed by the hay diet, had similar hay intake, diet digestibility, N balance and growth rate as compared to those

Effect of early experience and adaptation period on voluntary intake, digestion, and growth in Barbarine lambs given tannin-containing (Acacia cyanophylla Lindl. foliage) or tannin-free (oaten hay) diets

International Nuclear Information System (INIS)

Ben Salem, H.; Nefzaouia, A.; Ben Salem, I.; Makkar, H.P.S.; Hochlef, H.; Ben Salem, L.

2005-01-01

Our objective was to determine whether experience early in life and adaptation time (up to 72 days) to tannin-rich diets affect feed intake, digestion, nitrogen balance, and growth in Barbarine lambs given tannin-containing (Acacia cyanophylla Lindl., acacia) or tannin-free (oaten hay) diets later in life. Twelve experienced lambs (live-weight, LW: 13.2 ± 2.0 kg) were divided into two equal groups. Each group received air-dried acacia (tannin-containing diet) or oaten hay (hay, tannin free-diet) ad libitum. Twelve other inexperienced lambs (LW 12.3 ± 2.5 kg) were also divided into two equal groups. Each group received one of the above two diets. All animals were 4 months old at the start of this experiment and were supplemented with 300 g concentrate. To investigate the carry-over effect of tannins, the acacia-diet was removed on day 73, thus all lambs received thereafter the hay-diet for a further 24 days before starting a 6-day faecal collection period. Irrespective to early experience and adaptation time, the nutritive value of hay-diet was higher than that of acacia-diet and consequently lambs given hay performed better than those receiving acacia (P = 0.0001). Animals exposed to tannins early in life exhibited higher digestible crude protein intake (P = 0.0389), retained more N (P = 0.0963) and excreted more allantoin in urine (P = 0.0248) than the inexperienced lambs. Except plasma urea (P = 0.2923), the adaptation period to experimental diets affected significantly all measured parameters (P 0.0001). Animals adapted to diets for only 6 days exhibited the lowest acacia or hay intake and the highest diet digestibility compared to those adapted to these diets for 24, 48 or 72 days. Weight losses of inexperienced lambs adapted to acacia-diet for 6 days were associated with negative nitrogen balance. Sheep which received the acacia-diet, followed by the hay diet, had similar hay intake, diet digestibility, N balance and growth rate as compared to those offered

Identification of Spectral Regions for Quantification of Red Wine Tannins with Fourier Transform Mid-Infrared Spectroscopy

DEFF Research Database (Denmark)

Jensen, Jacob Skibsted; Egebo, Max; Meyer, Anne S.

2008-01-01

Accomplishment of fast tannin measurements is receiving increased interest as tannins are important for the mouthfeel and color properties of red wines. Fourier transform mid-infrared spectroscopy allows fast measurement of different wine components, but quantification of tannins is difficult due...... to interferences from spectral responses of other wine components. Four different variable selection tools were investigated for the identification of the most important spectral regions which would allow quantification of tannins from the spectra using partial least-squares regression. The study included...... to be particularly important for tannin quantification. The spectral regions identified from the variable selection methods were used to develop calibration models. All four variable selection methods identified regions that allowed an improved quantitative prediction of tannins (RMSEP = 69−79 mg of CE/L; r = 0...

The Effects of Pre-Fermentative Addition of Oenological Tannins on Wine Components and Sensorial Qualities of Red Wine.

Science.gov (United States)

Chen, Kai; Escott, Carlos; Loira, Iris; Del Fresno, Juan Manuel; Morata, Antonio; Tesfaye, Wendu; Calderon, Fernando; Benito, Santiago; Suárez-Lepe, Jose Antonio

2016-10-31

Today in the wine industry, oenological tannins are widely used to improve wine quality and prevent oxidation in wine aging. With the development of tannin products, new oenological tannins are developed with many specific functions, such as modifying antioxidant effect, colour stabilization and aroma modifications. The aim of this work is to investigate effects of pre-fermentative addition of oenological tannins on wine colour, anthocyanins, volatile compounds and sensorial properties. In this case, Syrah juice was extracted with classic flash thermovinification from fresh must in order to release more colour and tannins. Three types of oenological tannins, which are, respectively, derived from grape skin, seed ( Vitis vinifera ) and French oak ( Quercus robur and Querrus petraea ), were selected to carry out the experiments with seven treatments. Results indicated that tannin treatments significantly improved wine aroma complexity and sensorial properties. However, the concentration of some stable pigments such as Vitisin A, Vitisin A-Ac and Vitisin B was negatively affected by tannin additions. Nevertheless, by means of cluster analysis and principal component analysis, it was observed that higher alcohols were significantly promoted by grape seed tannin while most anthocyanins can be improved by addition of grape tannins. In conclusion, low amount of oenological tannin derived from grape seed is a promising method to be applied especially for young red wine making.

The Effects of Pre-Fermentative Addition of Oenological Tannins on Wine Components and Sensorial Qualities of Red Wine

Directory of Open Access Journals (Sweden)

Kai Chen

2016-10-01

Full Text Available Today in the wine industry, oenological tannins are widely used to improve wine quality and prevent oxidation in wine aging. With the development of tannin products, new oenological tannins are developed with many specific functions, such as modifying antioxidant effect, colour stabilization and aroma modifications. The aim of this work is to investigate effects of pre-fermentative addition of oenological tannins on wine colour, anthocyanins, volatile compounds and sensorial properties. In this case, Syrah juice was extracted with classic flash thermovinification from fresh must in order to release more colour and tannins. Three types of oenological tannins, which are, respectively, derived from grape skin, seed (Vitis vinifera and French oak (Quercus robur and Querrus petraea, were selected to carry out the experiments with seven treatments. Results indicated that tannin treatments significantly improved wine aroma complexity and sensorial properties. However, the concentration of some stable pigments such as Vitisin A, Vitisin A-Ac and Vitisin B was negatively affected by tannin additions. Nevertheless, by means of cluster analysis and principal component analysis, it was observed that higher alcohols were significantly promoted by grape seed tannin while most anthocyanins can be improved by addition of grape tannins. In conclusion, low amount of oenological tannin derived from grape seed is a promising method to be applied especially for young red wine making.

Percentage Level of Tannin fur Rabbit for Leather Concerning Stitch Tearing Strength, Tearing Strength and Flexibility

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Mustakim Mustakim

2012-02-01

Full Text Available The purpose of this study was to find out the appropriate of tannin level for rabbit fur leather concerning stitch tearing strength, tearing strength, and flexibility. The result were expected to contribute good information for the society, leather craftsman, and further researchers about fur leather tanning especially rabbit fur leather with tannin concerning stitch tearing strength, tearing strength and flexibility. The material that used were 12 pieces of four months of rabbit skin. The research method was Completely Randomized Design, consist of three treatments of tannin, they were: M1 (mimosa 15%, M2 (mimosa 20%, and M3 (mimosa 25%. Each of treatment hold on four repetition, the variables which measured were stitch tearing strength, tearing strength, and flexibility of fur leather. Data were  analysed by analysis variance followed by Duncan’s Multiple Range Test. The result of this research indicate that the use level of tannin give significant influence (P<0.05 among stitch tearing strength, tearing strength. It gave a very significant influence (P<0.01 for flexibility of rabbit fur leather. Based on the result, can be concluded that 25 % of tannin (mimosa, produce the best  result on stitch tearing strength and tearing strength. The increase of tannin offer will decrease the flexibility of fur leather but the lowest tannin produced the best flexibility of fur leather (15 percent. The best quality of rabbit fur leather produced by 25 % of tannin.   Keywords : leather, tannin, quality

Hydrolyzable tannins of tamaricaceous plants. III. Hellinoyl- and macrocyclic-type ellagitannins from Tamarix nilotica.

Science.gov (United States)

Orabi, Mohamed A A; Taniguchi, Shoko; Yoshimura, Morio; Yoshida, Takashi; Kishino, Kaori; Sakagami, Hiroshi; Hatano, Tsutomu

2010-05-28

Three new hellinoyl-type ellagitannins, nilotinins M4 (7), D7 (8), and D8 (9), and a new macrocyclic-type, nilotinin D9 (10), together with eight known tannins, hirtellins B (2), C (11), and F (12), isohirtellin C (13), tamarixinin A (3), tellimagrandins I and II, and 1,2,6-tri-O-galloyl-beta-d-glucose (14), were isolated from an aqueous acetone extract of Tamarix nilotica dried leaves. Nilotinin M4 (7) is a monomeric tannin possessing a hellinoyl moiety. The structure of 8 demonstrated replacement of one of the HHDP groups at the glucose core O-4/O-6 in ordinary dimeric tannins with a galloyl moiety at O-6. This is a new structural feature among the tamaricaceous ellagitannins. On the basis of the results, reported spectroscopic assignments for 2, 3, and the macrocyclic tannins 11-13 were revised. Unusual shifts in the NMR spectra of these macrocyclic tannins are also discussed in relation to their conformations. Several tannins isolated from T. nilotica were assessed for possible cytotoxic activity against four human tumor cell lines, and nilotinin D8 (9) and hirtellin A (1) showed high cytotoxic effects.

Wine and grape tannin interactions with salivary proteins and their impact on astringency: a review of current research.

Science.gov (United States)

McRae, Jacqui M; Kennedy, James A

2011-03-11

Astringency is an important characteristic of red wine quality. The sensation is generally thought to be produced by the interaction of wine tannins with salivary proteins and the subsequent aggregation and precipitation of protein-tannin complexes. The importance of wine astringency for marketability has led to a wealth of research on the causes of astringency and how tannins impact the quality of the sensation, particularly with respect to tannin structure. Ultimately, the understanding of how tannin structure impacts astringency will allow the controlled manipulation of tannins via such methods as micro-oxygenation or fining to improve the quality of wines.

Wine and Grape Tannin Interactions with Salivary Proteins and Their Impact on Astringency: A Review of Current Research

Directory of Open Access Journals (Sweden)

James A. Kennedy

2011-03-01

Full Text Available Astringency is an important characteristic of red wine quality. The sensation is generally thought to be produced by the interaction of wine tannins with salivary proteins and the subsequent aggregation and precipitation of protein-tannin complexes. The importance of wine astringency for marketability has led to a wealth of research on the causes of astringency and how tannins impact the quality of the sensation, particularly with respect to tannin structure. Ultimately, the understanding of how tannin structure impacts astringency will allow the controlled manipulation of tannins via such methods as micro-oxygenation or fining to improve the quality of wines.

Benefit from the association of small amounts of tannin-rich shrub foliage (Acacia cyanophylla Lindl.) with soya bean meal given as supplements to Barbarine sheep fed on oaten hay

International Nuclear Information System (INIS)

Ben Salem, H.; Makkar, H.P.S.; Nefzaoui, A.; Abidi, S.; Hassayoun, L.

2005-01-01

Two trials were conducted to test the hypotheses that (i) feeding small amount of a tanniniferous shrub foliage (Acacia cyanophylla Lindl., acacia) increases the proportion of rumen undegradable protein, and consequently benefits growth performance in Barbarine lamb; and (ii) such positive effect depends on the timing of feeding tannin source (i.e. acacia) relative to protein source (soya bean meal, SBM). Total (TT) and condensed tannin (CT) concentrations in air-dried acacia leaves used in this study averaged 29 g tannic acid and 48 g leucocyanidin equivalents per kg dry matter (DM), respectively. In trial 1, rumen fistulated ewes received oaten hay (hay) ad libitum and 200 g SBM (D1), D1 and 100 g acacia fed with the SBM (D2, mixed strategy) or as D2, but the SBM fed 1 h later than acacia when acacia was consumed completely (D3, sequential strategy). Hay intake, diet digestibility, rumen fermentation parameters (pH, ammonia nitrogen (NH 3 -N) and total volatile fatty acids) and in situ degradation of SBM nitrogen were similar between D1 and D2 (P > 0.05). However, the sequential strategy (D3) resulted in efficient use of N as reflected by the decrease of crude protein digestibility (CPD), plasma urea, NH 3 -N concentration and in situ degradation of SBM nitrogen. In trial 2, four groups each of six Barbarine lambs (initial LW 35.3 ± 3.7 kg) received for 90 days: hay ad libitum and 200 g SBM (D1), D1 and 20 g polyethylene glycol (PEG, MW 4000) mixed with SBM (D2), D1 and 100 g acacia with the SBM fed 1 h later when acacia was completely consumed (sequential strategy) (D3) or D3 and 20 g PEG fed with the SBM (D4). Polyethylene glycol was here used to deactivate tannins. Hay intake and DM, organic matter and neutral detergent fibre digestibility were similar among dietary treatment (P > 0.05). However, supplementing lambs with SBM and acacia without PEG (D3) resulted in a significant decrease (P 0.05). However, those supplemented with acacia without PEG (D3) had

Effects of chestnut tannins on performance and antioxidative status of transition dairy cows.

Science.gov (United States)

Liu, H W; Zhou, D W; Li, K

2013-09-01

This study was conducted to evaluate the effects of chestnut tannins (CT) on performance and antioxidative status of transition dairy cows. Twenty multiparous Chinese Holstein cows in late gestation were paired according to expected calving date and randomly assigned either to a diet supplemented with CT (CNT, 10 g of CT/kg of diet, dry matter basis) or to an unsupplemented control (CON) diet from 3 wk prepartum to 3 wk postpartum. Blood samples were taken on d -21, 1, 7, and 21 relative to calving for analysis of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and malondialdehyde (MDA). Liver samples were taken by puncture biopsy on d 1 and 21 relative to calving for analysis of SOD, GSH-Px, and MDA. Data were analyzed for a completely randomized block design with repeated measures. The addition of CT had no significant effects on dry matter intake, body weight, body condition score, milk yield, 3.5% fat-corrected milk yield, and milk composition but did decrease milk MDA and somatic cell score in transition dairy cows. Dry matter intake decreased from d -21 to 0 and increased from d 1 to 21 relative to calving across treatments. During the experimental period, body weight and body condition score decreased, whereas milk MDA and somatic cell score increased across treatments. A time effect was also observed for plasma MDA, which peaked on d 1 relative to calving and remained higher than that on d -21 relative to calving across treatments. Addition of CT decreased MDA concentrations in plasma and liver. Neither time nor CT × time effects were observed for SOD and T-AOC in plasma and SOD and GSH-Px in liver; a time effect was observed for plasma GSH-Px, which peaked on d 1 relative to calving and remained higher than those on d -21 relative to calving across treatments. Addition of CT increased SOD, GSH-Px, and T-AOC activities in plasma and SOD and GSH-Px activities in liver. In conclusion, addition of CT might

Nutrient content, in vitro ruminal fermentation characteristics and methane reduction potential of tropical tannin-containing leaves.

Science.gov (United States)

Bhatta, Raghavendra; Saravanan, Mani; Baruah, Luna; Sampath, Koratekere T

2012-12-01

Plant tannins as rumen modifiers are better than chemicals or antibiotic-based modifiers since these compounds are natural products which are environmentally friendly and therefore have a better acceptance with regard to feed safety issues. Tropical plants containing phenols such as tannins were found to suppress or eliminate protozoa from the rumen and reduce methane and ammonia production. The screening of these plants is an important step in the identification of new compounds and feed additives which might contribute to mitigate rumen methanogenesis. The present study was carried out to determine the efficacy of tannins from tropical tree leaves for their methane reduction properties. Activity of tannins, as represented by the increase in gas volume with the addition of polyethylene glycol (PEG)-6000 as a tannin binder (tannin bioassay) was highest in Ficus bengalensis (555%), followed by Azardirachta indica (78.5%). PEG addition did not alter (P > 0.05) methane percentage in Ficus racemosa, Glyricidia maculata, Leucena leucocephala, Morus alba and Semaroba glauca, confirming that tannins in these samples did not affect methanogenesis. The increase (P 0.05) in the protozoa population in Autocarpus integrifolia, Ficus bengalensis, Jatropha curcus, Morus alba and Sesbania grandiflora, demonstrating that methane reduction observed in these samples per se was not due to defaunation effect of the tannin. The increase in total volatile fatty acid concentration in samples with PEG ranged from 0.6% to > 70%. The highest increase (%) in NH(3)-N was recorded in Azardirachta indica (67.4), followed by Ficus mysoriensis (35.7) and Semaroba glauca (32.6) leaves, reflecting strong protein binding properties of tannin. The results of our study established that in vitro methanogenesis was not essentially related to the density of protozoa population. Tropical tree leaves containing tannins such as Autocarpus integrifolia, Jatropha curcus and Sesbania grandiflora have the

Calibration and validation of the {sup 14}C-labelled polyethylene glycol-binding assay for tannins in tropical browse

Energy Technology Data Exchange (ETDEWEB)

Mlambo, V. [Animal Production Unit, FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf (Austria)]. E-mail: vmlambo@agric.uniswa.sz; Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division of Nuclear Techniques in Agriculture and Food, International Atomic Energy Agency, Vienna (Austria)

2005-08-19

This study evaluates the radiolabelled polyethylene glycol (PEG)-binding procedure [Silanikove, N., Shinder, D., Gilboa, N., Eyal, M., Nitsan, Z., 1996. Polyethylene glycol-binding to plant samples as an assay for the biological effects of tannins: predicting the negative effects of tannins in Mediterranean browse on rumen degradation. J. Agric. Food Chem. 44, 3230-3234] for tannin analysis, using 27 tropical browse plants. In this method, the amount of PEG bound to a plant sample is assumed to be a reflection of its tannin content. The method was modified to exclude the use of non-tanniniferous substrate for estimating non-specific binding (NSB) in tannin-containing substrates. Non-specific binding values varied widely (0.4-2.8 mg PEG/100 mg DM tannin-free substrate) when the tannin-free substrate was changed from wheat straw to either rye grass or maize shoots. We therefore propose a modified radiolabelled PEG-binding method to estimate the level of PEG-binding (PEGb) to tannin-containing foliage without using tannin-free substrate to correct for non-specific binding. In this approach, incremental levels of each tanniniferous substrate were used to generate PEGb values. The resultant linear response was analysed and tannin activity was expressed as the slope of the response curve (PEGbSlope) observed for each substrate. The slope takes into account the non-specific binding in each substrate, thus PEGbSlope does not require correction for NSB using tannin-free samples. This approach improved the correlation between PEGb and the {sup 125}I-labelled bovine serum albumin precipitation assay. Relationships between the modified PEG-binding assay and radiolabelled bovine serum albumin assay, in vitro tannin bioassay and colorimetric assays are presented. (author)

Mangrove tannins and their flavanoid monomers as alternative steel corrosion inhibitors in acidic medium

Energy Technology Data Exchange (ETDEWEB)

Rahim, Afidah A. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia)]. E-mail: afidah@usm.my; Rocca, E. [Laboratoire de Chimie du Solide Mineral, Universite Henri Poincare, Nancy I BP 239, 54506 Vandoeuvre Les Nancy (France); Steinmetz, J. [Laboratoire de Chimie du Solide Mineral, Universite Henri Poincare, Nancy I BP 239, 54506 Vandoeuvre Les Nancy (France); Kassim, M.J. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia); Adnan, R. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia); Sani Ibrahim, M. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia)

2007-02-15

The inhibitive behaviour on steel of flavanoid monomers that constitute mangrove tannins namely catechin, epicatechin, epigallocatechin and epicatechingallate was investigated in an aerated HCl solution via electrochemical methods. The monomers were found to be mainly cathodic inhibitors and the inhibition efficiency was dependent on concentration. To explain the adsorptive behaviour of the molecules on the steel surface, a semiempirical approach involving quantum chemical calculations using HyperChem 6.0 was undertaken. The HOMO electronic density of the molecule was used to explain the inhibiting mechanism. The most probable adsorption centers were found in the vicinity of the phenolic groups. In a second part, the use of mangrove tannin, extracted from the mangrove barks as steel corrosion inhibitors in acidic media was investigated and its inhibitive efficiency was compared with that of commercial mimosa, quebracho and chestnut tannins. The inhibitive performance of mangrove tannins was comparable to the other tannins investigated, indicating their potential in corrosion protection.

Mangrove tannins and their flavanoid monomers as alternative steel corrosion inhibitors in acidic medium

International Nuclear Information System (INIS)

Rahim, Afidah A.; Rocca, E.; Steinmetz, J.; Kassim, M.J.; Adnan, R.; Sani Ibrahim, M.

2007-01-01

The inhibitive behaviour on steel of flavanoid monomers that constitute mangrove tannins namely catechin, epicatechin, epigallocatechin and epicatechingallate was investigated in an aerated HCl solution via electrochemical methods. The monomers were found to be mainly cathodic inhibitors and the inhibition efficiency was dependent on concentration. To explain the adsorptive behaviour of the molecules on the steel surface, a semiempirical approach involving quantum chemical calculations using HyperChem 6.0 was undertaken. The HOMO electronic density of the molecule was used to explain the inhibiting mechanism. The most probable adsorption centers were found in the vicinity of the phenolic groups. In a second part, the use of mangrove tannin, extracted from the mangrove barks as steel corrosion inhibitors in acidic media was investigated and its inhibitive efficiency was compared with that of commercial mimosa, quebracho and chestnut tannins. The inhibitive performance of mangrove tannins was comparable to the other tannins investigated, indicating their potential in corrosion protection

Heavy Metal-Free Tannin from Bark for Sustainable Energy Storage.

Science.gov (United States)

Mukhopadhyay, Alolika; Jiao, Yucong; Katahira, Rui; Ciesielski, Peter N; Himmel, Michael; Zhu, Hongli

2017-12-13

A novel renewable cathode made from earth abundant, low-cost materials can contribute to the intermittent storage needs of renewable energy-based society. In this work, we report for the first-time tannin from Nature as a cathode material. Our approach exploits the charge storage mechanism of the redox active quinone moiety. Tannins extracted from tree bark using environmental friendly aqueous solvents have the highest phenol content (5.56 mol g -1 ) among all the natural phenolic biopolymers, 5000 times higher than lignin. Tannins coupled with a conductive polymer polypyrrole acquire high specific capacitance values of 370 F g -1 at 0.5 A g -1 as well as excellent rate performance of 196 F g -1 at 25 A g -1 . Additionally, we employed carbonized wood as an electrode substrate to produce a sustainable electrochemical device with dramatically improved performance compared to conventional devices. The high surface area provided by the well-aligned, cellular porosity of wood-derived substrate combined with the high mobility of ions and electrons in the carbonized cell walls and deposited tannin can achieve an areal capacitance of 4.6 F cm -2 at 1 mA cm -2 , which is 1.5 times higher than activated wood carbon.

In vitro biological activity of tannins from Acacia and other tree fruits ...

African Journals Online (AJOL)

This study was designed to investigate impact of tannins on in vitro ruminal fermentation parameters as well as relationships between concentration and in vitro biological activity of tannins present in tree fruits. Dry and mature fruits of known phenolic content harvested from Acacia nilotica, A. erubescens, A. erioloba, ...

Heating and reduction affect the reaction with tannins of wine protein fractions differing in hydrophobicity.

Science.gov (United States)

Marangon, Matteo; Vincenzi, Simone; Lucchetta, Marco; Curioni, Andrea

2010-02-15

During the storage, bottled white wines can manifest haziness due to the insolubilisation of the grape proteins that may 'survive' in the fermentation process. Although the exact mechanism of this occurrence is not fully understood, proteins and tannins are considered two of the key factors involved in wine hazing, since their aggregation leads to the formation of insoluble particles. To better understand this complex interaction, proteins and tannins from the same unfined Pinot grigio wine were separated. Wine proteins were then fractionated by hydrophobic interaction chromatography (HIC). A significant correlation between hydrophobicity of the wine protein fractions and the haze formed after reacting with wine tannins was found, with the most reactive fractions revealing (by SDS-PAGE and RP-HPLC analyses) the predominant presence of thaumatin-like proteins. Moreover, the effects of both protein heating and disulfide bonds reduction (with dithiotreithol) on haze formation in the presence of tannins were assessed. These treatments generally resulted in an improved reactivity with tannins, and this phenomenon was related to both the surface hydrophobicity and composition of the protein fractions. Therefore, haze formation in wines seems to be related to hydrophobic interactions occurring among proteins and tannins. These interactions should occur on hydrophobic tannin-binding sites, whose exposition on the proteins can depend on both protein heating and reduction. Copyright 2009 Elsevier B.V. All rights reserved.

Evaluation of Tannins and Anthocyanins in Marquette, Frontenac, and St. Croix Cold-Hardy Grape Cultivars

Directory of Open Access Journals (Sweden)

Somchai Rice

2017-09-01

Full Text Available Cold-hardy grape cultivars have become popular in northern regions. Wines from these cultivars are low in tannins and lighter in color compared to Vitis vinifera. The northern regions are striving to enhance desired ″full body″ and red color qualities in the wine produced from cold-hardy grapes. The objective of this study was to compare tannin and pigment content in skins and seeds of three cold-hardy red grape cultivars, at two time points, from two locations, using the Adams-Harbertson (A-H assay. The A-H assay is based on protein precipitation and spectrophotometry. Total tannin concentrations detected in Frontenac, Marquette, and St. Croix berries, ranged from 0.29 to 0.66 mg/berry catechin equivalents (CE. Bitter seed tannins were most abundant in Marquette berries (0.54 ± 0.66 mg/berry CE. Softer skin tannins were most abundant in St. Croix berries (0.24 ± 0.19 mg/berry CE. Monomeric anthocyanins contributed to over 60% of the total color at pH 4.9 and were highest in St. Croix skins (74.21% of the total color at pH 4.9. Varying amounts of short polymeric pigments and long polymeric pigments were present in grape skins, indicating that pigmented tannins had already formed by harvest. This is the first evaluation of tannins and pigments in Frontenac, Marquette, and St. Croix berries.

Moessbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

Energy Technology Data Exchange (ETDEWEB)

Jaen, Juan A., E-mail: jjaen@ancon.up.ac.p [Universidad de Panama, Depto. de Quimica Fisica, CITEN, Lab. No. 105, Edificio de Laboratorios Cientificos-VIP (Panama); Navarro, Cesar [Universidad de Panama, Escuela de Quimica, Facultad de Ciencias Naturales, Exactas y Tecnologia (Panama)

2009-07-15

Fourier transform infrared spectroscopy and Moessbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Moessbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

Mössbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

Science.gov (United States)

Jaén, Juan A.; Navarro, César

2009-07-01

Fourier transform infrared spectroscopy and Mössbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Mössbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

Moessbauer and infrared spectroscopy as a diagnostic tool for the characterization of ferric tannates

International Nuclear Information System (INIS)

Jaen, Juan A.; Navarro, Cesar

2009-01-01

Fourier transform infrared spectroscopy and Moessbauer spectroscopy are use for the characterization and qualitative analysis of hydrolysable and condensed tannates. The two classes of tannates may be differentiated from the characteristic IR pattern. Moessbauer proof that a mixture of mono- and bis-type ferric tannate complexes, and an iron(II)-tannin complex are obtained from the interaction of hydrolysable tannins (tannic acid and chestnut tannin) and condensed tannins (mimosa and quebracho) with a ferric nitrate solution. At pH 7, a partially hydrolyzed ferric tannate complex was also obtained.

Analysis and Testing of Bisphenol A—Free Bio-Based Tannin Epoxy-Acrylic Adhesives

Directory of Open Access Journals (Sweden)

Shayesteh Jahanshahi

2016-04-01

Full Text Available A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, 13C-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 °C for 12 h. FT-MIR, 13C-NMR and MALDI-TOF analysis have confirmed that the resin has been prepared under these conditions. The joints bonded with this resin were tested for block shear strength. The results obtained indicated that the best strength performance was obtained by the bioepoxy-acrylate adhesive resin prepared at 95 °C for a 12-h reaction.

Effect of Fermentation and Cooking on Soluble and Bound Phenolic Profiles of Finger Millet Sour Porridge.

Science.gov (United States)

Gabaza, Molly; Shumoy, Habtu; Muchuweti, Maud; Vandamme, Peter; Raes, Katleen

2016-10-12

The aim of this study was to evaluate the soluble and bound phenolic content of finger millet and the impact of process induced changes on phenolic profiles of their sour porridge. Finger millet porridge and intermediate products were collected from four groups of households in the Hwedza communal area, Zimbabwe, after which soluble and bound phenolic compounds (PC) including condensed tannins (CT) were quantified. Bound PC and CT contributed 95% of the total PC and CT. The CT were only detected in the red varieties. Major individual PC identified were catechin occurring in the soluble fraction only, while ferulic, sinapic, and salicylic acid were mainly present in the bound fraction. Fermentation and cooking caused a more than 2-fold increase in soluble PC, CT, and individual PC. Improved traditional processing techniques optimized for improved bioavailability and health benefits of phenolics are highly relevant for the low income populations.

In vivo and in situ measurements of the digestive characteristics of sainfoin in comparison with lucerne fed to sheep as fresh forages at two growth stages and as hay.

Science.gov (United States)

Aufrère, J; Dudilieu, M; Poncet, C

2008-09-01

In vivo and in situ digestive characteristics of sainfoin (Onobrychis viciifolia L., a tannin-rich forage) and lucerne (Medicago sativa L., a tannin-free forage) were compared to evaluate the effects of condensed tannins (CT) and growth stage (vegetative v. early flowering) in experiment 1. In experiment 2, the hays of the two forages, harvested at early flowering, were compared. Ingestibility, organic matter digestibility (OMD) and nitrogen (N) retention were measured in sheep fed sainfoin and lucerne fresh forages and hays. The loss of dry matter (DM) and N from polyester bags suspended in the rumen, abomasum and small intestine was also measured using rumen fistulated sheep and other intestine fistulated sheep. Nitrogen content was lower in sainfoin than in lucerne. Content of CT in sainfoin decreased with growth stage (3.5 to 2.5 g CT/kg DM) and was lower for sainfoin hay (0.6 g CT/kg DM). Ingestibility and OMD did not differ between fresh-fed forage species. Total N tract digestibility in vivo was much lower for sainfoin than for lucerne fresh forages (mean value 0.540 v. 0.721, P forages. Nitrogen degradability in the rumen determined by the nylon bag technique (DegN) was lower for sainfoin than for lucerne when forages were studied both fresh (mean value 0.608 and 0.818, respectively) and as hays (0.631 and 0.767). The efficiency of forage N digestion (ENd) was higher for sainfoin at the vegetative stage. Compared with lucerne, sainfoin greatly increased the in situ estimate of forage N escaping the rumen but decreased its intestinal digestibility.

Use of nuclear techniques for characterization of vegetable tannins, extracted from waste of forestry production in Cuba

International Nuclear Information System (INIS)

Santana Romero, J. L.; Martinez Luzardo, F.; Vargas Guerra, L.; Melo Cala, P.; Garcia Guillen, M.; Isaac Olive, K.; Codorniu Hernandez, E.; Estevez, P.; Roque, Cordoba A.; Benitez, M.

1999-01-01

Vegetable Tannins are polyphenolic plant secondary metabolites, widely distributed in all parts of trees and herbs.The role of these substances in many metabolic processes is very important. Vegetable tannins have probably implication as anti nutritional factors, decreasing up-take of diet protein assimilation by cattle. On the other hand, protective antioxidant and antimutagenic properties has been describes for these compounds. Characterization of vegetable tannins is an important task in order to find new sources of natural raw materials with several applications. Analytical determination of tannins and their characterization is still a problem at present days in order to qualify the food quality for ruminants. Protein precipitation capacity as function of pH, competitive protein and ADN binding assays , and determination of tannins concentration are describes.Radioisotopic labelling of protein and tannins were used in order to carried out all the determinations

High-throughput micro plate vanillin assay for determination of tannin in sorghum grain

Science.gov (United States)

Sorghum tannins are phenolic compounds that offer health promoting antioxidant properties. The conventional HCl-vanillin assay for determining tannin content is a time-consuming method for screening large sample sets as seen in association mapping panels or breeder nursery samples. The objective of ...

Identification of Potential Plants Producing Tannin-protein Complex for a-amylase as Botanical Pesticide

Directory of Open Access Journals (Sweden)

Asriyah Firdausi

2013-05-01

Full Text Available Research  on  the  development  of  botanical  pesticides  should  be developed  through  new  methods,  such  as  by  inhibiting the  activity  of  digestive enzymes  by  secondary  metabolites.  The  aim  of  this  study  was  to  identify some  of  potential  plants  as  a  source  of  tannin-protein  complexes  to  inhibitthe  activity  of  - amylase.  The  study  of  identification  of  potential  plants producing  the  active  ingredient  tannin-protein  complex  was  divided  into  three stages,  1  identification  of  potential  plants  producing  tannin,  2  isolation  of tannin-protein  complexes,  and  3  in  vitro  test  of  tannin-protein  complexes effect  of  the  -amylase activity.  Some  of  the observed  plants  were  sidaguri  leaf (Sida rhombifolia, melinjo leaf (Gnetum gnemon, gamal leaf (Gliricidia sepium,lamtoro  leaf  (Leucaena  leucocephala ,  betel  nut  (Areca  catechu ,  and  crude gambier  (Uncaria  gambir a s  a  source of  tannins  and  melinjo  seed was  used  asprotein  source.  Betel  nut  and  melinjo  seed  were  the  best  source  of  tannin-protein  complex,  tannin  content  1.77  mg  TAE/mL  with  antioxidant  activity  of  90%,the  ability  to  inhibit  the  activity  of  -amylase by  95%  with  IC 50  values  of 10 mg/mL.Key words: Tannin, protein, -amylase, botanical pesticides,Areca catechu, Gnetum gnemon.

Physico-mechanical properties of plywood bonded with ecological adhesives from Acacia mollissima tannins and lignosulfonates

Science.gov (United States)

Rhazi, Naima; Oumam, Mina; Sesbou, Abdessadek; Hannache, Hassan; Charrier-El Bouhtoury, Fatima

2017-06-01

The objective of this research was to develop ecological adhesives for bonding plywood panels using lignosulfonates, a common waste product of the wood pulp industry, and natural tannin extracted from Moroccan bark of Acacia mollissima using different process. Natural tannin and lignin were used in wood adhesives formulation to substitute resins based on phenol and formaldehyde. To achieve this, the lignosulfonates were glyoxalated to enhance their reactivity and the used tannins obtained by three different extraction methods were compared with commercial mimosa tannin. The proportion of Acacia mollissima tannins and lignosulfonates, the pressing time, the pressing temperature, and the pressure used were studied to improve mechanical properties, and bonding quality of plywood panel. The properties of plywood panels produced with these adhesives were tested in accordance with normative tests. Thus, the tensile strength, and the shear strength were measured. The results showed that the performance of the plywood panels made using biobased tannin adhesives was influenced by physical conditions such as pressure, press temperature as well as by chemical conditions, such as the tannin-lignin ratio. It exhibited excellent mechanical properties comparable to commercially available phenol-formaldehyde plywood adhesives. This study showed that biobased adhesives formulations presented good and higher mechanical performance and no formaldehyde emission. Contribution to the topical issue "Materials for Energy harvesting, conversion and storage II (ICOME 2016)", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

Quantitative analysis of red wine tannins using Fourier-transform mid-infrared spectrometry.

Science.gov (United States)

Fernandez, Katherina; Agosin, Eduardo

2007-09-05

Tannin content and composition are critical quality components of red wines. No spectroscopic method assessing these phenols in wine has been described so far. We report here a new method using Fourier transform mid-infrared (FT-MIR) spectroscopy and chemometric techniques for the quantitative analysis of red wine tannins. Calibration models were developed using protein precipitation and phloroglucinolysis as analytical reference methods. After spectra preprocessing, six different predictive partial least-squares (PLS) models were evaluated, including the use of interval selection procedures such as iPLS and CSMWPLS. PLS regression with full-range (650-4000 cm(-1)), second derivative of the spectra and phloroglucinolysis as the reference method gave the most accurate determination for tannin concentration (RMSEC = 2.6%, RMSEP = 9.4%, r = 0.995). The prediction of the mean degree of polymerization (mDP) of the tannins also gave a reasonable prediction (RMSEC = 6.7%, RMSEP = 10.3%, r = 0.958). These results represent the first step in the development of a spectroscopic methodology for the quantification of several phenolic compounds that are critical for wine quality.

The growth of protozoa in buffalo rumen liquid with addition of tannin in vitro

International Nuclear Information System (INIS)

Irawan Sugoro; I-Yunianto

2006-01-01

Tannin is anti nutrient compound which can be used to increased by pass protein in ruminant. The source of tannin was used from acacia leaf powder (Acacia mangium). The concentration of tannin was determined by precipitated of 125 I-BSA method. The experiments were carried out by in vitro method in buffalo rumen liquid. The treatments were A(1.25%); B (2.5%), C (5%) and Kontrol (0%). The result showed that tannin supplementation was decreased the number of protozoa and the lowest growth occurred on A (1.25%). The composition of protozoa was decreased and the viability of protozoa population showed that nine isolates has high viability, i.e. Dasytricha rumination, Entodinium ecaudatum f. caudatum, Ostracodinium mammosum, Elytroplastron bubali, Entodinium nanellum, Charonin ventriculi, Entodinium rostratum, Ostracodinium bubali dan Metadinium medium. (author)

Biomolecular Interactions of Tannin Isolated from Oenothera gigas with Liposomes.

Science.gov (United States)

Sekowski, Szymon; Ionov, Maksim; Dubis, Alina; Mavlyanov, Saidmukhtar; Bryszewska, Maria; Zamaraeva, Maria

2016-04-01

We have examined the interaction between hydrolysable tannin 1-O-galloyl-4,6-hexahydroxydiphenoyl-β-D-glucose (OGβDG) with neutral liposomes as a model of cell membranes composed of three lipids: lecithin, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at different mass ratios. OGβDG in the concentration range 0.5-15 µg/ml (0.4-12 µM) strongly interacts with liposomal membranes by changing their structure, surface charge and fluidity. Used OGβDG molecules decrease and increase the rigidity of hydrophilic surface and hydrophobic parts of liposomes, respectively. At higher concentrations of tannin (>15 µM), liposomes are aggregated. Fourier Transform Infra-Red (FTIR) analysis showed that mainly -OH groups from OGβDG and also PO(2-) groups from phospholipids are responsible for the interaction. Obtained data indicate the importance of membrane lipid composition in interactions between tannins and cells.

Red wine tannins fluidify and precipitate lipid liposomes and bicelles. A role for lipids in wine tasting?

Science.gov (United States)

Furlan, Aurélien L; Castets, Aurore; Nallet, Frédéric; Pianet, Isabelle; Grélard, Axelle; Dufourc, Erick J; Géan, Julie

2014-05-20

Sensory properties of red wine tannins are bound to complex interactions between saliva proteins, membranes taste receptors of the oral cavity, and lipids or proteins from the human diet. Whereas astringency has been widely studied in terms of tannin-saliva protein colloidal complexes, little is known about interactions between tannins and lipids and their implications in the taste of wine. This study deals with tannin-lipid interactions, by mimicking both oral cavity membranes by micrometric size liposomes and lipid droplets in food by nanometric isotropic bicelles. Deuterium and phosphorus solid-state NMR demonstrated the membrane hydrophobic core disordering promoted by catechin (C), epicatechin (EC), and epigallocatechin gallate (EGCG), the latter appearing more efficient. C and EGCG destabilize isotropic bicelles and convert them into an inverted hexagonal phase. Tannins are shown to be located at the membrane interface and stabilize the lamellar phases. These newly found properties point out the importance of lipids in the complex interactions that happen in the mouth during organoleptic feeling when ingesting tannins.

Bacterial and protozoal communities and fatty acid profile in the rumen of sheep fed a diet containing added tannins.

Science.gov (United States)

Vasta, Valentina; Yáñez-Ruiz, David R; Mele, Marcello; Serra, Andrea; Luciano, Giuseppe; Lanza, Massimiliano; Biondi, Luisa; Priolo, Alessandro

2010-04-01

This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of Butyrivibrio fibrisolvens, which converts C(18:2) c9-c12 (linoleic acid [LA]) to C(18:2) c9-t11 (rumenic acid [RA]) and then RA to C(18:1) t11 (vaccenic acid [VA]); we also sampled for Butyrivibrio proteoclasticus, which converts VA to C(18:0) (stearic acid [SA]). Tannins increased (P tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (P tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The B. proteoclasticus population was lower (-30.6%; P tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations.

Environment-friendly adhesives for surface bonding of wood-based flooring using natural tannin to reduce formaldehyde and TVOC emission.

Science.gov (United States)

Kim, Sumin

2009-01-01

The objective of this research was to develop environment-friendly adhesives for face fancy veneer bonding of engineered flooring using the natural tannin form bark in the wood. The natural wattle tannin adhesive were used to replace UF resin in the formaldehyde-based resin system in order to reduce formaldehyde and volatile organic compound (VOC) emissions from the adhesives used between plywoods and fancy veneers. PVAc was added to the natural tannin adhesive to increase viscosity of tannin adhesive for surface bonding. For tannin/PVAc hybrid adhesives, 5%, 10%, 20% and 30% of PVAc to the natural tannin adhesives were added. tannin/PVAc hybrid adhesives showed better bonding than the commercial natural tannin adhesive with a higher level of wood penetration. The initial adhesion strength was sufficient to be maintained within the optimum initial tack range. The standard formaldehyde emission test (desiccator method), field and laboratory emission cell (FLEC) and VOC analyzer were used to determine the formaldehyde and VOC emissions from engineered flooring bonded with commercial the natural tannin adhesive and tannin/PVAc hybrid adhesives. By desiccator method and FLEC, the formaldehyde emission level of each adhesive showed the similar tendency. All adhesives satisfied the E(1) grade (below 1.5 mg/L) and E(0) grade (below 0.5 mg/L) with UV coating. VOC emission results by FLEC and VOC analyzer were different with the formaldehyde emission results. TVOC emission was slightly increased as adding PVAc.

Effect of tannins from Dioscoreae Cirrhosae and Galla chinensis on gamma ray exposed mice

International Nuclear Information System (INIS)

Yue Feng; Wang Qingmin; Tang Ying; Li Yu; Shi Hai; Lei Chengxiang

2012-01-01

Objective: To explore the protective effect of tannins from Dioscoreae Cirrhosae and Galla chinensis on radiation injury. Methods: Forty male Chinese Kunming mice were randomly divided into non-radiation group, radiation group without drugs,radiation group with tea polyphenols, radiation group with tannins from Dioscoreae Cirrhosae and radiation group with tannins from Galla chinensis. The radiation groups were irradiated with a single exposure of 8.0 Gy γ rays from 60 Co. The mice were intragastric ally administered 2 h before radiation and were done 18 h after radiation. The 30-day survival rate, the mean survival time and the protective coefficients were confirmed. Results: All the mice of radiation group without drugs died in 16 d after exposure,and their mean survival time was (12.0±2.45) d, while the radiation groups with tannins from Dioscoreae Cirrhosae, with tannins from Galla chinensis and with tea polyphenols were (26.25±7.13) d, (21.88±8.89) d and (23.25±9.33) d respectively. There was significant difference in comparison with radiation group without drugs (P 60 Co and could present a significant protection effect on radiation injuries. (authors)

Influence of food tannins on certain aspects of iron metabolism : Part 1 -- Absorption and excretion in normal and anemic rats

Energy Technology Data Exchange (ETDEWEB)

Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukher ee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

1979-04-01

Studies on absorption and excretion of iron by isotopic and non-isotopic methods in normal and hemolytic anemic rats indicate that dietary food tannins at a dose of 0.5 mg/kg body wt/day tend to increase iron excretion in normal rats but more iron is absorbed or retained in tannin-fed anemic rats and absorption of iron is comparable to that in normal control. Both in vivo and in vitro tannin at a high dose (2.0 mg/kg body wt/day) inhibits the iron absorption in experimental animals. The interference of food tannins (0.5 kg/mg body wt/day) with absorption of iron (/sup 59/Fe) varies with plant species from which tannin has been prepared. Normal iron balance in tannin-fed (0.5 mg/kg body wt/day) anemic rats may result from increased assimilation of tannin-bound iron in intestinal mucosa, and absorbed tannin appears to remove unabsorbed iron.

Wine and Grape Tannin Interactions with Salivary Proteins and Their Impact on Astringency: A Review of Current Research

OpenAIRE

James A. Kennedy; Jacqui M. McRae

2011-01-01

Astringency is an important characteristic of red wine quality. The sensation is generally thought to be produced by the interaction of wine tannins with salivary proteins and the subsequent aggregation and precipitation of protein-tannin complexes. The importance of wine astringency for marketability has led to a wealth of research on the causes of astringency and how tannins impact the quality of the sensation, particularly with respect to tannin structure. Ultimately, the understanding of ...

The Effects of Pre-Fermentative Addition of Oenological Tannins on Wine Components and Sensorial Qualities of Red Wine

OpenAIRE

Kai Chen; Carlos Escott; Iris Loira; Juan Manuel del Fresno; Antonio Morata; Wendu Tesfaye; Fernando Calderon; Santiago Benito; Jose Antonio Suárez-Lepe

2016-01-01

Today in the wine industry, oenological tannins are widely used to improve wine quality and prevent oxidation in wine aging. With the development of tannin products, new oenological tannins are developed with many specific functions, such as modifying antioxidant effect, colour stabilization and aroma modifications. The aim of this work is to investigate effects of pre-fermentative addition of oenological tannins on wine colour, anthocyanins, volatile compounds and sensorial properties. In th...

Vegetable and synthetic tannins induce hormesis/toxicity in sea urchin early development and in algal growth

Energy Technology Data Exchange (ETDEWEB)

De Nicola, Elena [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy); Meric, Suereyya [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Gallo, Marialuisa [Campania Regional Agency for Environmental Protection (ARPAC), I-80143 Naples (Italy); Iaccarino, Mario [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy); Della Rocca, Claudio [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Lofrano, Giusy [Department of Civil Engineering, Salerno University, I-84084 Fisciano (Italy); Russo, Teresa [Campania Regional Agency for Environmental Protection (ARPAC), I-80143 Naples (Italy); Pagano, Giovanni [Italian National Cancer Institute, G. Pascale Foundation, via M. Semmola, I-80131 Naples (Italy)]. E-mail: gbpagano@tin.it

2007-03-15

Mimosa tannin and phenol-based synthetic tannin (syntan) were tested for toxicity to sea urchin (Paracentrotus lividus and Sphaerechinus granularis) early development and to marine algal growth (Dunaliella tertiolecta). Sea urchin embryogenesis was affected by vegetable tannin and syntan water extracts (VTWE and STWE) at levels {>=}1 mg/L. Developmental defects were significantly decreased at VTWE and STWE levels of 0.1 and 0.3 mg/L when control cultures displayed suboptimal quality, i.e. <70% 'viable' (normal or retarded) larvae. Fertilization success of sea urchin sperm was increased up to 0.3 mg/L STWE or VTWE, then was inhibited by increasing tannin levels (1-30 mg/L). Offspring abnormalities, following sperm exposure to VTWE or STWE, showed the same shift from hormesis to toxicity. Cell growth bioassays in D. tertiolecta exposed to VTWE or STWE (0.1-30 mg/L) showed non-linear concentration-related toxicity. Novel criteria are suggested in defining control quality that should reveal hormetic effects. - Vegetable tannin and synthetic tannins were moderately toxic or displayed hormetic effects in sea urchins and in algae. Re-defining control quality is needed for evaluating hormetic effects.

Vegetable and synthetic tannins induce hormesis/toxicity in sea urchin early development and in algal growth

International Nuclear Information System (INIS)

De Nicola, Elena; Meric, Suereyya; Gallo, Marialuisa; Iaccarino, Mario; Della Rocca, Claudio; Lofrano, Giusy; Russo, Teresa; Pagano, Giovanni

2007-01-01

Mimosa tannin and phenol-based synthetic tannin (syntan) were tested for toxicity to sea urchin (Paracentrotus lividus and Sphaerechinus granularis) early development and to marine algal growth (Dunaliella tertiolecta). Sea urchin embryogenesis was affected by vegetable tannin and syntan water extracts (VTWE and STWE) at levels ≥1 mg/L. Developmental defects were significantly decreased at VTWE and STWE levels of 0.1 and 0.3 mg/L when control cultures displayed suboptimal quality, i.e. <70% 'viable' (normal or retarded) larvae. Fertilization success of sea urchin sperm was increased up to 0.3 mg/L STWE or VTWE, then was inhibited by increasing tannin levels (1-30 mg/L). Offspring abnormalities, following sperm exposure to VTWE or STWE, showed the same shift from hormesis to toxicity. Cell growth bioassays in D. tertiolecta exposed to VTWE or STWE (0.1-30 mg/L) showed non-linear concentration-related toxicity. Novel criteria are suggested in defining control quality that should reveal hormetic effects. - Vegetable tannin and synthetic tannins were moderately toxic or displayed hormetic effects in sea urchins and in algae. Re-defining control quality is needed for evaluating hormetic effects

Levels of Tannins and Flavonoids in Medicinal Plants: Evaluating Bioprospecting Strategies

Science.gov (United States)

Siqueira, Clarissa Fernanda de Queiroz; Cabral, Daniela Lyra Vasconcelos; Peixoto Sobrinho, Tadeu José da Silva; de Amorim, Elba Lúcia Cavalcanti; de Melo, Joabe Gomes; Araújo, Thiago Antônio de Sousa; de Albuquerque, Ulysses Paulino

2012-01-01

There are several species of plants used by traditional communities in the Brazilian semiarid. An approach used in the search for natural substances that possess therapeutic value is ethnobotany or ethnopharmacology. Active substances that have phenolic groups in their structure have great pharmacological potential. To establish a quantitative relationship between the species popularly considered to be antimicrobial, antidiabetic, and antidiarrheal, the contents of tannins and flavonoids were determined. The plant selection was based on an ethnobotanical survey conducted in a community located in the municipality of Altinho, northeastern Brazil. For determination of tannin content was utilized the technique of radial diffusion, and for flavonoids, an assay based on the complexation of aluminum chloride. The group of plants with antimicrobial indications showed a higher content of tannins compared to the control groups. The results evidence suggests a possible relationship between these compounds and the observed activity. PMID:21969842

Dietary inclusion of tannin extract from red quebracho trees (Schinopsis spp. in the rabbit meat production

Directory of Open Access Journals (Sweden)

Maria Elena Cossu

2010-01-01

Full Text Available Two levels (1% and 3% of condensed tannin extract from red quebracho (QT were added to a diet of growing rabbits in a 6-wk feeding trial up to 12 wk of age. Health status was unaf- fected by the QT supplementation. The E. coli count of caecal content denoted a bactericidal activity of the QT. Weight gain and slaughter weigh were significantly higher and conversion index was sig- nificantly lower in rabbits fed QT diets, compared to those fed the control diet (P<0.05. Meat traits, as well the meat fatty acid profile weren’t influenced by the QT supplementation. Our results contributed to increase the knowledge on the dietary use of QT in the rabbit. QT extract supplemented at 1% and 3% in fattening rabbits diet had a clear beneficial effect on live performance. Further studies are needed to assess if supplementing diets with QT can be a valuable strategy.

Condensation model for the ESBWR passive condensers

International Nuclear Information System (INIS)

Revankar, S. T.; Zhou, W.; Wolf, B.; Oh, S.

2012-01-01

In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data from separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)

Characterization of a tannin by NMR

International Nuclear Information System (INIS)

Teixeira, Antonio C.F.; Silva, Antonio J.R. da

1993-01-01

This work presents the observations performed during the process of characterization of Geraniin, a crystalline tannin, which is able to undergo hydrolysis, isolated from Phyllanthus tennellus, a plant known in Brazil as 'quebra-pedra'. The methodology is presented and the chemical analysis performed for the identification are presented and discussed. The obtained results are compared to the existing literature

Use of wood ash in the treatment of high tannin sorghum for poultry ...

African Journals Online (AJOL)

conniek

Abstract. A study was conducted to investigate the effects of wood ash treatment on the nutritional value of high tannin sorghum. High tannin sorghum was either soaked in wood ash slurry and then germinated for four days or soaked in wood ash extract and germinated for 28 hours or germinated after soaking in water.

Use of wood ash in the treatment of high tannin sorghum for poultry ...

African Journals Online (AJOL)

A study was conducted to investigate the effects of wood ash treatment on the nutritional value of high tannin sorghum. High tannin sorghum was either soaked in wood ash slurry and then germinated for four days or soaked in wood ash extract and germinated for 28 hours or germinated after soaking in water. Chemical ...

Bacterial and Protozoal Communities and Fatty Acid Profile in the Rumen of Sheep Fed a Diet Containing Added Tannins ▿

Science.gov (United States)

Vasta, Valentina; Yáñez-Ruiz, David R.; Mele, Marcello; Serra, Andrea; Luciano, Giuseppe; Lanza, Massimiliano; Biondi, Luisa; Priolo, Alessandro

2010-01-01

This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of Butyrivibrio fibrisolvens, which converts C18:2 c9-c12 (linoleic acid [LA]) to C18:2 c9-t11 (rumenic acid [RA]) and then RA to C18:1 t11 (vaccenic acid [VA]); we also sampled for Butyrivibrio proteoclasticus, which converts VA to C18:0 (stearic acid [SA]). Tannins increased (P tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (P tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The B. proteoclasticus population was lower (−30.6%; P tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations. PMID:20173064

Establishment of the callus and cell suspension culture of ...

African Journals Online (AJOL)

The objective of this work was the optimization of the conditions of callus and cell suspension culture of Elaeagnus angustifolia for the production of condensed tannins. The effects of different conditions on the callus growth and the production of condensed tannins were researched. The leaf tissue part of E. angustifolia was ...

Condensers

International Nuclear Information System (INIS)

Andrieux, M.B.

1984-01-01

Characteristics of the condenser cooling waters of various French 900 MW nuclear power plants. Design and description of various types of condensers: condensers feeded directly with river water, condensers feeded by cooling towers, condensers feeded with sea water of brackish water. Presentation of the main problems encountered with the brass bundles (ammoniacal corrosion, erosion of the peripheral tubes, vibrations of the tubes), with the titanium bundles, with the tubular plates, the tubes-tubular plates assemblies, the coatings of the condenser water chamber (sea water), the vapor by-pass and with the air inlet. Analysis of the in service performances such as condensation pressure, oxygen content and availability [fr

Benefit from the association of small amounts of tannin-rich shrub foliage (Acacia cyanophylla Lindl.) with soya bean meal given as supplements to Barbarine sheep fed on oaten hay

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, H. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia)]. E-mail: bensalem.hichem@iresa.agrinet.tn; Makkar, H.P.S. [Animal Production and Health Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna (Austria); Nefzaoui, A.; Abidi, S. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Hassayoun, L. [Institut National de la Recherche Agronomique de Tunisie, Laboratoire des Productions Animales et Fourrageres, Ariana (Tunisia); Ecole Superieure d' Agriculture de Mateur, Mateur (Tunisia)

2005-08-19

Two trials were conducted to test the hypotheses that (i) feeding small amount of a tanniniferous shrub foliage (Acacia cyanophylla Lindl., acacia) increases the proportion of rumen undegradable protein, and consequently benefits growth performance in Barbarine lamb; and (ii) such positive effect depends on the timing of feeding tannin source (i.e. acacia) relative to protein source (soya bean meal, SBM). Total (TT) and condensed tannin (CT) concentrations in air-dried acacia leaves used in this study averaged 29 g tannic acid and 48 g leucocyanidin equivalents per kg dry matter (DM), respectively. In trial 1, rumen fistulated ewes received oaten hay (hay) ad libitum and 200 g SBM (D1), D1 and 100 g acacia fed with the SBM (D2, mixed strategy) or as D2, but the SBM fed 1 h later than acacia when acacia was consumed completely (D3, sequential strategy). Hay intake, diet digestibility, rumen fermentation parameters (pH, ammonia nitrogen (NH{sub 3}-N) and total volatile fatty acids) and in situ degradation of SBM nitrogen were similar between D1 and D2 (P > 0.05). However, the sequential strategy (D3) resulted in efficient use of N as reflected by the decrease of crude protein digestibility (CPD), plasma urea, NH{sub 3}-N concentration and in situ degradation of SBM nitrogen. In trial 2, four groups each of six Barbarine lambs (initial LW 35.3 {+-} 3.7 kg) received for 90 days: hay ad libitum and 200 g SBM (D1), D1 and 20 g polyethylene glycol (PEG, MW 4000) mixed with SBM (D2), D1 and 100 g acacia with the SBM fed 1 h later when acacia was completely consumed (sequential strategy) (D3) or D3 and 20 g PEG fed with the SBM (D4). Polyethylene glycol was here used to deactivate tannins. Hay intake and DM, organic matter and neutral detergent fibre digestibility were similar among dietary treatment (P > 0.05). However, supplementing lambs with SBM and acacia without PEG (D3) resulted in a significant decrease (P < 0.001) of CPD (0.664 versus 0.597, respectively for D1 and

High-throughput micro-plate HCL-vanillin assay for screening tannin content in sorghum grain

Science.gov (United States)

Sorghum contains tannin which is a phenolic compound that offers health promoting antioxidant capacity. The HCl-vanillin assay is a common and time consuming method for determining tannin content, but is not efficient for screening large sample sets as seen in association mapping panels or breeding ...

Valorization of Tunisian alfa fibres and sumac tannins for the elaboration of biodegradable insulating panels

Science.gov (United States)

Saad, Houda; Charrier, Bertrand; Ayed, Naceur; Charrier-El-Bouhtoury, Fatima

2017-10-01

Alfa leaves are important renewable raw materials in Tunisia where they are used basically in handcrafts and paper industry. Sumac is also an abundant species in Tunisia known for its high tannin content and is basically used in traditional medicine. To valorize these natural resources, we studied, for the first time, the possibility of making insulating panels based on alfa fibres and sumac tannins based adhesive. Firstly, alfa leaves were treated with an alkali solution as it is one of the standard procedures commonly used in the paper industry to extract cellulosic fibres. Mercerization effects were studied by characterizing fibres thermal properties and fibres surface morphology. Secondly, the sumac tannin based resin was formulated and characterized. Finally, the insulating panel was elaborated and characterized by determining its thermal conductivity. The thermal gravimetric analysis results show improvement in the thermal stability of fibres after alkali treatment. Environmental Scanning Electron Microscopy showed changes on treated alfa surface which could promote the fibre-matrix adhesion. The reactivity of sumac tannins to formaldehyde test (Stiasny number) showed the possible use of sumac tannins in wood adhesive formulation. Thermomechanical analysis and strength analysis of sumac tannin/hexamin based resin highlighted acceptable bonding properties. The thermal conductivity measurement showed an average value equal to 0.110 W/m K. Contribution to the topical issue "Materials for Energy harvesting, conversion and storage II (ICOME 2016)", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

Comparative study of wine tannin classification using Fourier transform mid-infrared spectrometry and sensory analysis.

Science.gov (United States)

Fernández, Katherina; Labarca, Ximena; Bordeu, Edmundo; Guesalaga, Andrés; Agosin, Eduardo

2007-11-01

Wine tannins are fundamental to the determination of wine quality. However, the chemical and sensorial analysis of these compounds is not straightforward and a simple and rapid technique is necessary. We analyzed the mid-infrared spectra of white, red, and model wines spiked with known amounts of skin or seed tannins, collected using Fourier transform mid-infrared (FT-MIR) transmission spectroscopy (400-4000 cm(-1)). The spectral data were classified according to their tannin source, skin or seed, and tannin concentration by means of discriminant analysis (DA) and soft independent modeling of class analogy (SIMCA) to obtain a probabilistic classification. Wines were also classified sensorially by a trained panel and compared with FT-MIR. SIMCA models gave the most accurate classification (over 97%) and prediction (over 60%) among the wine samples. The prediction was increased (over 73%) using the leave-one-out cross-validation technique. Sensory classification of the wines was less accurate than that obtained with FT-MIR and SIMCA. Overall, these results show the potential of FT-MIR spectroscopy, in combination with adequate statistical tools, to discriminate wines with different tannin levels.

Selective detection and recovery of gold at tannin-immobilized non-conducting electrode.

Science.gov (United States)

Banu, Khaleda; Shimura, Takayoshi; Sadeghi, Saman

2015-01-01

A tannin-immobilized glassy carbon electrode (TIGC) was prepared via electrochemical oxidation of the naturally occurring polyphenolic mimosa tannin, which generated a non-conducting polymeric film (NCPF) on the electrode surface. The fouling of the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferricyanide ions as a redox marker. The NCPF was permselective to HAuCl4, and the electrochemical reduction of HAuCl4 to metallic gold at the TIGC electrode was evaluated by recording the reduction current during cyclic voltammetry measurement. In the mixed electrolyte containing HAuCl4 along with FeCl3 and/or CuCl2, the NCPF remained selective toward the electrochemical reduction of HAuCl4 into the metallic state. The chemical reduction of HAuCl4 into metallic gold was also observed when the NCPF was inserted into an acidic gold solution overnight. The adsorption capacity of Au(III) on tannin-immobilized carbon fiber was 29±1.45 mg g(-1) at 60°C. In the presence of excess Cu(II) and Fe(III), tannin-immobilized NCPF proved to be an excellent candidate for the selective detection and recovery of gold through both electrochemical and chemical processes. Copyright © 2014 Elsevier B.V. All rights reserved.

Habitat influence on antioxidant activity and tannin concentrations of Spondias tuberosa.

Science.gov (United States)

de Sousa Araújo, Thiago Antônio; de Almeida e Castro, Valerium Thijan Nobre; de Amorim, Elba Lúcia Cavalcanti; de Albuquerque, Ulysses Paulino

2012-06-01

Different habitat conditions can be responsible for the production of secondary metabolites and for the antioxidant properties of plant products. Thus, the aim of this study was to evaluate whether the antioxidant activity and tannin concentrations in the stem bark of Spondias tuberosa Arruda (Anacardiaceae) varied with collection site. The bark was collected from 25 individual trees, distributed in five different landscape units, as follows: agroforestry gardens, areas of pastures, maize cultivation areas, mountain areas and mountain bases, with the former 3 being considered as anthropogenic habitats, and the latter 2 considered as habitats with native coverage. The study was conducted in the rural area of the city of Altinho, Pernambuco State (Northeast Brazil). The DPPH (1,1-diphenyl-2-picrylhydrazyl) method was used to measure the antioxidant activity and tannin concentrations were evaluated by using the radial diffusion method. The results demonstrated that there were no significant differences among the tannin concentrations of the individuals from the native (6.27% ± 1.75) or anthropogenic areas (4.63% ± 2.55), (H = 2.24; p > 0.05). In contrast, there were significant differences (H = 5.1723; p 0.05) or in the anthropogenic areas (r = 0.38; p > 0.05). Because the variation of the antioxidant capacity of S. tuberosa bark was not accompanied by a variation in the tannin concentration, this property may be related to the presence of other metabolite(s).

Acid hydrolysis of crude tannins from infructescence of Platycarya strobilacea Sieb. et Zucc to produce ellagic acid.

Science.gov (United States)

Zhang, Liangliang; Wang, Yongmei; Xu, Man

2014-01-01

The infructescence of Platycarya strobilacea Sieb. et Zucc is a well-known traditional medicine in China, Japan and Korea. The infructescence of P. strobilacea Sieb. et Zucc is a rich source of ellagitannins that are composed of ellagic acid (EA) and gallic acid, linked to a sugar moiety. The aim of this study was to prepare EA by acid hydrolysis of crude tannins from the infructescence of P. strobilacea Sieb. et Zucc, and establish a new technological processing method for EA. The natural antioxidant EA was prepared by using the water extraction of infructescence of P. strobilacea Sieb. et Zucc, evaporation, condensation, acid hydrolysis and prepared by the process of crystallisation. The yield percentage of EA from crude EA was more than 20% and the purity of the product was more than 98%, as identified by using HPLC. The structure was identified on the basis of spectroscopic analysis and comparison with authentic compound.

DISTRIBUTION OF ALKALOIDS AND TANNINS IN THE CRASSULACEAE

NARCIS (Netherlands)

STEVENS, JF; THART, H; VANHAM, CHJ; ELEMA, ET; VANDENENT, MMVX; WILDEBOER, M; ZWAVING, JH

Alkaloid and tannin levels of 36 species of the Crassulaceae were compared. The taxa investigated were Crassula multicava, Echeveria venezuelensis, Pachyphytum compactum, Kalanchoe (two sop.), Bryophyllum daigremontianum, Sedum (23 spp.), Aeonium (four spp.) and Sempervivum (three spp.). Apart from

NMR and molecular modeling of wine tannins binding to saliva proteins: revisiting astringency from molecular and colloidal prospects.

Science.gov (United States)

Cala, Olivier; Pinaud, Noël; Simon, Cécile; Fouquet, Eric; Laguerre, Michel; Dufourc, Erick J; Pianet, Isabelle

2010-11-01

In organoleptic science, the association of tannins to saliva proteins leads to the poorly understood phenomenon of astringency. To decipher this interaction at molecular and colloidal levels, the binding of 4 procyanidin dimers (B1-4) and 1 trimer (C2) to a human saliva proline-rich peptide, IB7(14), was studied. Interactions have been characterized by measuring dissociation constants, sizes of complexes, number, and nature of binding sites using NMR (chemical shift variations, diffusion-ordered spectroscopy, and saturation transfer diffusion). The binding sites were identified using molecular mechanics, and the hydrophilic/hydrophobic nature of the interactions was resolved by calculating the molecular lipophilicity potential within the complexes. The following comprehensive scheme can be proposed: 1) below the tannin critical micelle concentration (CMC), interaction is specific, and the procyanidin anchorage always occurs on the same three IB7(14) sites. The tannin 3-dimensional structure plays a key role in the binding force and in the tannin's ability to act as a bidentate ligand: tannins adopting an extended conformation exhibit higher affinity toward protein and initiate the formation of a network. 2) Above the CMC, after the first specific hydrophilic interaction has taken place, a random hydrophobic stacking occurs between tannins and proteins. The whole process is discussed in the general frame of wine tannins eliciting astringency.

Selective detection and recovery of gold at tannin-immobilized non-conducting electrode

Energy Technology Data Exchange (ETDEWEB)

Banu, Khaleda, E-mail: kbanu@ucla.edu [Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095 (United States); Venture Business Laboratory, Center for Advanced Science and Innovation, Osaka University, Suita, Osaka 565-0871 (Japan); Shimura, Takayoshi [Venture Business Laboratory, Center for Advanced Science and Innovation, Osaka University, Suita, Osaka 565-0871 (Japan); Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University (Japan); Sadeghi, Saman, E-mail: samsadeghi@mednet.ucla.edu [Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095 (United States)

2015-01-01

Highlights: • Selective detection of gold at non-conducting (NC) polymer modified electrode. • Mimosa tannin oxidized on glassy carbon electrode surface as NC polymeric film. • Permselective diffusion and mediated electron transfer at NC electrode surface. • Chemical recovery of gold is due to the reducing ability of the NC polymeric film. • Adsorption capacity of Au(III) on carbon fiber was 29 ± 1.45 mg g{sup −1} at 60 °C. - Abstract: A tannin-immobilized glassy carbon electrode (TIGC) was prepared via electrochemical oxidation of the naturally occurring polyphenolic mimosa tannin, which generated a non-conducting polymeric film (NCPF) on the electrode surface. The fouling of the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferricyanide ions as a redox marker. The NCPF was permselective to HAuCl{sub 4}, and the electrochemical reduction of HAuCl{sub 4} to metallic gold at the TIGC electrode was evaluated by recording the reduction current during cyclic voltammetry measurement. In the mixed electrolyte containing HAuCl{sub 4} along with FeCl{sub 3} and/or CuCl{sub 2}, the NCPF remained selective toward the electrochemical reduction of HAuCl{sub 4} into the metallic state. The chemical reduction of HAuCl{sub 4} into metallic gold was also observed when the NCPF was inserted into an acidic gold solution overnight. The adsorption capacity of Au(III) on tannin-immobilized carbon fiber was 29 ± 1.45 mg g{sup −1} at 60 °C. In the presence of excess Cu(II) and Fe(III), tannin-immobilized NCPF proved to be an excellent candidate for the selective detection and recovery of gold through both electrochemical and chemical processes.

Selective detection and recovery of gold at tannin-immobilized non-conducting electrode

International Nuclear Information System (INIS)

Banu, Khaleda; Shimura, Takayoshi; Sadeghi, Saman

2015-01-01

Highlights: • Selective detection of gold at non-conducting (NC) polymer modified electrode. • Mimosa tannin oxidized on glassy carbon electrode surface as NC polymeric film. • Permselective diffusion and mediated electron transfer at NC electrode surface. • Chemical recovery of gold is due to the reducing ability of the NC polymeric film. • Adsorption capacity of Au(III) on carbon fiber was 29 ± 1.45 mg g −1 at 60 °C. - Abstract: A tannin-immobilized glassy carbon electrode (TIGC) was prepared via electrochemical oxidation of the naturally occurring polyphenolic mimosa tannin, which generated a non-conducting polymeric film (NCPF) on the electrode surface. The fouling of the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferricyanide ions as a redox marker. The NCPF was permselective to HAuCl 4 , and the electrochemical reduction of HAuCl 4 to metallic gold at the TIGC electrode was evaluated by recording the reduction current during cyclic voltammetry measurement. In the mixed electrolyte containing HAuCl 4 along with FeCl 3 and/or CuCl 2 , the NCPF remained selective toward the electrochemical reduction of HAuCl 4 into the metallic state. The chemical reduction of HAuCl 4 into metallic gold was also observed when the NCPF was inserted into an acidic gold solution overnight. The adsorption capacity of Au(III) on tannin-immobilized carbon fiber was 29 ± 1.45 mg g −1 at 60 °C. In the presence of excess Cu(II) and Fe(III), tannin-immobilized NCPF proved to be an excellent candidate for the selective detection and recovery of gold through both electrochemical and chemical processes

Identification of spectral regions for the quantification of red wine tannins with fourier transform mid-infrared spectroscopy.

Science.gov (United States)

Jensen, Jacob S; Egebo, Max; Meyer, Anne S

2008-05-28

Accomplishment of fast tannin measurements is receiving increased interest as tannins are important for the mouthfeel and color properties of red wines. Fourier transform mid-infrared spectroscopy allows fast measurement of different wine components, but quantification of tannins is difficult due to interferences from spectral responses of other wine components. Four different variable selection tools were investigated for the identification of the most important spectral regions which would allow quantification of tannins from the spectra using partial least-squares regression. The study included the development of a new variable selection tool, iterative backward elimination of changeable size intervals PLS. The spectral regions identified by the different variable selection methods were not identical, but all included two regions (1485-1425 and 1060-995 cm(-1)), which therefore were concluded to be particularly important for tannin quantification. The spectral regions identified from the variable selection methods were used to develop calibration models. All four variable selection methods identified regions that allowed an improved quantitative prediction of tannins (RMSEP = 69-79 mg of CE/L; r = 0.93-0.94) as compared to a calibration model developed using all variables (RMSEP = 115 mg of CE/L; r = 0.87). Only minor differences in the performance of the variable selection methods were observed.

The effect of tannins on Mediterranean ruminant ingestive behavior: the role of the oral cavity.

Science.gov (United States)

Lamy, Elsa; Rawel, Harshadrai; Schweigert, Florian J; Capela E Silva, Fernando; Ferreira, Ana; Costa, Ana Rodrigues; Antunes, Célia; Almeida, André Martinho; Coelho, Ana Varela; Sales-Baptista, Elvira

2011-03-25

Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion according to animal physiological limits of tolerance for plant secondary metabolites. This review will detail the effects of dietary tannins on feeding behavior, and the role of the oral cavity in this process, with focus on such ruminant species. The role of salivary protein profile in tannin perception in the oral cavity, and as a defense mechanism, will be discussed.

Recovery of uranium from low uranium concentration waste water using collagen fiber immobilized bayberry tannin

International Nuclear Information System (INIS)

Wu Yun; Long Xianming; Zhao Ning; Liao Pinxue

2012-01-01

Tannin, extracted from plants, is a kind of natural polyphenol, which is able to chelate with various metal ions and also exhibits selectivity in some extent. The collagen fiber immobilized bayberry tannin was prepared by the immobilization of bayberry tannin onto collagen fiber through the Mannich reaction. Experiment of the adsorption of U from U containing wastewater by using collagen fiber immobilized bayberry tannin suggested that the pH increase of U containing wastewater can promote the adsorption of U onto the adsorbent. When the pH was 4.5 and the initial concentration of U was 300.0 mg/L, the adsorption capacity of U reached the maximum of 52 mg/g while the other impurity metal ions were less than 16.0 mg/g, thus exhibiting excellent selectivity. The treatment of wastewater can be optimized by changing the U concentration, inlet rate of wastewater, and the ratio of column height/diameter etc. In addition. the adsorbed U can be desorbed using 0.1 mol/L HNO 3 solution when the column was saturated, the column can also be re used for the treatment of U containing wastewater after the column is washed by deionized water, collagen fiber immobilized bayberry tannin exhibit selectivity, high adsorption capacity, good reusability when adsorbed U. (authors)

Negative plates for dry-charged lead storage batteries. [higher charging capacity when impregnated with tannin solution

Energy Technology Data Exchange (ETDEWEB)

Fiedler, V; Malikova, V; Weber, H

1970-09-15

Impregnation of negative plates with acid solutions of sulfomethylated tannins was found to improve the charging properties at low temperatures. Methods for synthesizing tannins are described. Charging capacity at 0/sup 0/ was 7.3A. (RWR)

Efficacy of tannins from Mimosa pudica and tannic acid in neutralizing cobra (Naja kaouthia venom

Directory of Open Access Journals (Sweden)

FY Sia

2011-01-01

Full Text Available In the present study, the effectiveness of Mimosa pudica tannins (MPT in neutralizing the lethality of Naja kaouthia venom was compared with commercially derived tannins. Preincubation of MPT with N. kaouthia venom maintained 100% survival of mice after 24 hours. The mouse group in which there was no preincubation, no protection against the effects of the venom was observed. M. pudica tannin was found to be more effective in neutralizing the lethality of N. kaouthia venom when compared to commercial tannic acid. Two protein spots were missing in the two-dimensional gel electrophoresis (2-DE of the MPT treated mouse indicating the down-regulation of venom proteins. The results from this study indicated that tannins obtained from M. pudica are better than tannic acid in neutralizing the lethality of N. kaouthia venom in vitro. However, further investigations are required to establish that M. pudica has potential for treating N. kaouthia snakebites.

Comparative Analysis of Tannins in the Rhizomes of Great Burnet (Sanguisorba officinalis L.)

OpenAIRE

Mukhametgaliev N.R.; Idrisova G.I.; Gilazieva G.Z.

2015-01-01

Quantitative analysis of the content of tannins in the rhizomes of great burnet (Sanguisorba officinalis L.) was performed using Leventhal’s permanganometric method, its Kursanov's modification, and spectrophotometry. Advantages and disadvantages of the methods used were discussed to determine the quantitative content of tannins in the active parts of different plants. New locations of S. officinalis populations in various regions of the Republic of Tatarstan were detected. The discovered pop...

Production of tannase through submerged fermentation of tannin-containing plant extracts by Bacillus licheniformis KBR6.

Science.gov (United States)

Das Mohapatra, Pradeep K; Mondal, Keshab C; Pati, Bikas R

2006-01-01

Tannins are water-soluble polyphenolic compounds found in plants as secondary metabolites. The presence of these substances in the barks of eight different plants was initially examined and their crude extracts were used separately as a substrate for production of tannase through submerged fermentation by Bacillus licheniformis KBR6. Tannase production as well as biodegradation of the substrate reached a maximum within 15 to 18 h against crude tannin extract obtained from Anacardium occidentale. Among different concentrations of the crude tannin tested, 0.5% (w/v) induced maximum synthesis of enzyme. Tannase production was higher by almost two-fold in the presence of crude tannin compared to pure tannic acid used as a substrate. It seems that industrial production of tannase, using bark extract of A. occidentale can be a very simple and suitable alternative to presently used procedures.

Measuring the molecular dimensions of wine tannins: comparison of small-angle X-ray scattering, gel-permeation chromatography and mean degree of polymerization.

Science.gov (United States)

McRae, Jacqui M; Kirby, Nigel; Mertens, Haydyn D T; Kassara, Stella; Smith, Paul A

2014-07-23

The molecular size of wine tannins can influence astringency, and yet it has been unclear as to whether the standard methods for determining average tannin molecular weight (MW), including gel-permeation chromatography (GPC) and depolymerization reactions, are actually related to the size of the tannin in wine-like conditions. Small-angle X-ray scattering (SAXS) was therefore used to determine the molecular sizes and corresponding MWs of wine tannin samples from 3 and 7 year old Cabernet Sauvignon wine in a variety of wine-like matrixes: 5-15% and 100% ethanol; 0-200 mM NaCl and pH 3.0-4.0, and compared to those measured using the standard methods. The SAXS results indicated that the tannin samples from the older wine were larger than those of the younger wine and that wine composition did not greatly impact on tannin molecular size. The average tannin MWs as determined by GPC correlated strongly with the SAXS results, suggesting that this method does give a good indication of tannin molecular size in wine-like conditions. The MW as determined from the depolymerization reactions did not correlate as strongly with the SAXS results. To our knowledge, SAXS measurements have not previously been attempted for wine tannins.

Comparison of extraction protocols to determine differences in wine-extractable tannin and anthocyanin in Vitis vinifera L. cv. Shiraz and Cabernet Sauvignon grapes.

Science.gov (United States)

Bindon, Keren A; Kassara, Stella; Cynkar, Wieslawa U; Robinson, Ella M C; Scrimgeour, Neil; Smith, Paul A

2014-05-21

Cabernet Sauvignon and Shiraz grapes were sourced from different regions within Australia, and microvinified with a skin contact period of 6 days. Grape samples were extracted using two protocols: a 15% v/v ethanol, 10 g/L tartaric acid extract of gently crushed berries (wine-like, WL) and a 50% v/v ethanol, pH 2 extract of grape berry homogenate. It was found that in WL extracts, grape tannin and anthocyanin concentrations were strongly related to wine tannin, anthocyanin and color density achieved during the skin contact period. No relationship was observed for grape tannin concentration analyzed in homogenate extracts and wine tannin, but a strong, positive relationship was found for anthocyanin concentration. When the data obtained from homogenate extraction was treated separately by grape variety, a stronger relationship between grape and wine tannin concentration was observed. Tannin compositional analysis in wines indicated that higher tannin concentrations were due to the extraction of tannin of higher molecular mass during fermentation, most likely from grape skins.

Phenols and tannins contents of Anacardium occidentale Linn and Anadenanthera colubrina (Vell.) Brenan exposed to gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Santos, Gustavo Henrique Farias dos [Universidade Federal de Pernambuco (GERAR/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Edvane Borges da [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academico de Vitoria; Amorim, Elba Lucia Cavalcanti de; Peixoto Sobrinho, Tadeu, E-mail: elba@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Ciencias Farmaceuticas; Lima, Claudia Sampaio de Andrade [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

2011-07-01

Anacardium occidentale Linn (cajueiro) and Anadenanthera colubrina (Vell.) Brenan (angico) are very know as a source of phenolic compounds, mainly tannins. The aim of this study was to evaluate the difference of phenols and tannins contents of crude extracts were measured after irradiation of barks and leaves of each plant source, using a source of {sup 60}Co. The crude extracts were divided into control group and three groups which were separately after exposition to gamma radiation, in doses of 5; 7.5 and 10 kGy. From each group, the total phenols were quantified by the Folin-Ciocalteau method, while the contents of tannins were assessed using precipitation of the casein technique. For all doses, the total phenol and tannin percentages from 'cajueiro' barks presented no significant statistical alteration. However, for the leaves of 'cajueiro', their chemical composite levels significantly changed with the radiation absorbed dose. On the other hand, the gamma irradiation did not cause alterations in total phenols and tannins content of extracts from 'angico'. (author)

Phenols and tannins contents of Anacardium occidentale Linn and Anadenanthera colubrina (Vell.) Brenan exposed to gamma radiation

International Nuclear Information System (INIS)

Santos, Gustavo Henrique Farias dos; Silva, Edvane Borges da; Amorim, Elba Lucia Cavalcanti de; Peixoto Sobrinho, Tadeu; Lima, Claudia Sampaio de Andrade

2011-01-01

Anacardium occidentale Linn (cajueiro) and Anadenanthera colubrina (Vell.) Brenan (angico) are very know as a source of phenolic compounds, mainly tannins. The aim of this study was to evaluate the difference of phenols and tannins contents of crude extracts were measured after irradiation of barks and leaves of each plant source, using a source of 60 Co. The crude extracts were divided into control group and three groups which were separately after exposition to gamma radiation, in doses of 5; 7.5 and 10 kGy. From each group, the total phenols were quantified by the Folin-Ciocalteau method, while the contents of tannins were assessed using precipitation of the casein technique. For all doses, the total phenol and tannin percentages from 'cajueiro' barks presented no significant statistical alteration. However, for the leaves of 'cajueiro', their chemical composite levels significantly changed with the radiation absorbed dose. On the other hand, the gamma irradiation did not cause alterations in total phenols and tannins content of extracts from 'angico'. (author)

Modification chimique d'antioxydants pour les rendre lipophiles : application aux tannins

OpenAIRE

Poaty-Poaty , Bouddah

2009-01-01

Ce travail fut pour moi une expérience pétillante en dépit de l'énorme stress qu'il a occasionné. J'en tire une réelle satisfaction personnelle car cela est presque exclusivement le fruit de ma réflexion et de ma persévérance dans l'effort; In the order to use natural antioxidants in lipidic substances, we wanted to make lipophilic of tannins by grafting on them carbonaceous chains through mild and simple chemical modifications. First, we used model substrates of tannins (phenol, catechol, ga...

Influence of food tannins on certain aspects of iron metabolism : Part 2 -- Storage and transport in normal and anemic rats

Energy Technology Data Exchange (ETDEWEB)

Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukherjee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

1979-04-01

Administration of tannin (0.5 mg/kg body wt/day) from fruits and vegetables lowers the iron content in liver, spleen and bone marrow with an elevation in Total Iron Binding Capacity (TIBC) of serum and serum iron concentration in normal rats. The same dose of tannin increases the iron content in storage tissues, particularly bone marrow of hemolytic anemic rats. In anemic rats, TIBC is decreased and serum iron concentration is raised from anemic level to approximately normal value due to ingestion of tannin. Radioiron administration, either by oral or by intravenous route, also elicits similar results. Recovery of iron storage and transport values from the anemic to the normal condition by tannin (0.5 mg/kg) varies with the source of tannin used. Thus more iron required for compensating the anemic conditions is retained within their body by tannin (0.5 mg/kg) which appears to reduce the loss of peripheral iron probably by protecting the lysis of red cells.

The Effect of Tannins on Mediterranean Ruminant Ingestive Behavior: The Role of the Oral Cavity

Directory of Open Access Journals (Sweden)

Elsa Lamy

2011-03-01

Full Text Available Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion according to animal physiological limits of tolerance for plant secondary metabolites. This review will detail the effects of dietary tannins on feeding behavior, and the role of the oral cavity in this process, with focus on such ruminant species. The role of salivary protein profile in tannin perception in the oral cavity, and as a defense mechanism, will be discussed.

Properties of wine polymeric pigments formed from anthocyanin and tannins differing in size distribution and subunit composition.

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Bindon, Keren; Kassara, Stella; Hayasaka, Yoji; Schulkin, Alex; Smith, Paul

2014-11-26

To explore the effect of tannin composition on pigment formation, model ferments of purified 3-O-monoglucoside anthocyanins (ACN) were conducted either alone or in the presence of two different tannins. Tannins were isolated from grape seeds (Sd) or skins (Sk) following exhaustive extraction in 70% v/v acetone. The Sd and Sk tannin fractions had a mean degree of polymerization of 5.2 and 25.6, respectively. The Sd fraction was highly galloylated, at 22%, but galloylation was Wine color and polymeric pigment were highest in the treatment containing ACN+Sd and similar in the ACN+Sk and ACN treatments. The same trend between treatments was observed for total and polymeric nonbleachable pigments. Only minor changes in tannin subunit composition were found following ACN incorporation, but the size distribution of polymeric pigments determined by gel permeation chromatography decreased, in particular for the ACN+Sk treatment. Color incorporation in the higher molecular mass range was lower for ACN+Sk wines than for ACN+Sd wines. Compositional differences between the two tannin fractions may therefore limit the incorporation of ACNs in the colored form. The results suggest that in the ACN+Sk and ACN treatments, the formation of lower molecular mass oligomeric pigments was favored. In polymeric pigments derived from ACNs, the presence of ethyl- and vinyl-linked ACNs to the level of trimers was identified using mass spectrometry.

Chitosan mediated enhancement of hydrolysable tannin in Phyllanthus debilis Klein ex Willd via plant cell suspension culture.

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V, Malayaman; N, Sisubalan; R P, Senthilkumar; S, Sheik Mohamed; R, Ranjithkumar; M, Ghouse Basha

2017-11-01

Phyllanthus debilis Klein ex Willd. is wild medicinal plant used in the traditional system of medicine. This plant has been actively used for hepatoprotection and to cure many diseases including jaundice and so on; which leads to complete extinction of this particular species. Therefore, the chitosan mediated cost effective cell suspension method has been developed for the production of hydrolysable tannin. The hydrolysable tannins are the main therapeutically active constituents with antioxidant, anticancer, and antimicrobial properties. An in vitro cell suspension culture was optimized by adding chitosan for production of hydrolysable tannin. According to the growth kinetics, a maximum biomass of 4.46±0.06g fresh cell weight and 1.33±0.04g dry cell weight were obtained from the optimal suspension medium consisted of MS medium+0.5mgL -1 BAP+1.5mgL -1 NAA. Chitosan was treated at the stationary phase which leads to the highest accumulation of hydrolysable tannin compared to the untreated control. Hydrolysable tannin was observed and compared using HPLC at the Rt of 4.91 in both chitosan treated and untreated cells. This is the first ever report where use of chitosan has been done to enhance the production of the hydrolysable tannin in P. debilis using cell suspension culture technique. Copyright © 2017 Elsevier B.V. All rights reserved.

Tannins and Bacitracin Differentially Modulate Gut Microbiota of Broiler Chickens

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Juan María Díaz Carrasco

2018-01-01

Full Text Available Antibiotic growth promoters have been used for decades in poultry farming as a tool to maintain bird health and improve growth performance. Global concern about the recurrent emergence and spreading of antimicrobial resistance is challenging the livestock producers to search for alternatives to feed added antibiotics. The use of phytogenic compounds appears as a feasible option due to their ability to emulate the bioactive properties of antibiotics. However, detailed description about the effects of in-feed antibiotics and alternative natural products on chicken intestinal microbiota is lacking. High-throughput sequencing of 16S rRNA gene was used to study composition of cecal microbiota in broiler chickens supplemented with either bacitracin or a blend of chestnut and quebracho tannins over a 30-day grow-out period. Both tannins and bacitracin had a significant impact on diversity of cecal microbiota. Bacitracin consistently decreased Bifidobacterium while other bacterial groups were affected only at certain times. Tannins-fed chickens showed a drastic decrease in genus Bacteroides while certain members of order Clostridiales mainly belonging to the families Ruminococcaceae and Lachnospiraceae were increased. Different members of these groups have been associated with an improvement of intestinal health and feed efficiency in poultry, suggesting that these bacteria could be associated with productive performance of birds.

Glulam Properties of Fast-growing Species Using Mahogany Tannin Adhesive

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Andi Sri Rahayu Diza Lestari

2015-09-01

Full Text Available Manufacturing glued laminated timber (glulam can help overcome the limited availability of large-sized timber, and the use of bio-adhesives may resolve environmental problems associated with synthetic adhesives containing high formaldehyde contents. Tannin adhesive is a bio-adhesive that can be used as alternative glue in the manufacture of glulam. The purpose of this study was to determine the physical and mechanical properties of glulam made with mahogany (Swietenia sp. tannin adhesive and wood from three fast-growing species, namely pine (Pinus merkusii, jabon (Anthocephalus cadamba, and sengon (Falcataria moluccana. Glulam (3 cm × 6 cm × 120 cm in thickness, width, and length, respectively was manufactured with three layers of lamina. The physical and mechanical properties of the glulams were tested based on relevant standards. The results showed that pine glulam fulfilled the standard for the modulus of rupture and modulus of elasticity, while sengon glulam met the standard for shear strength. In the delamination test, sengon glulam was resistant to immersion in cold water and hot water. All glulams had low formaldehyde emission levels and therefore fulfilled the standard requirements. The results showed that the tannin adhesive from mahogany bark was equal in quality to methylene diphenyl di-isocyanate for glulam manufacturing.

SUPPLEMENTATION EFFECTS OF TANNIN AND SAPONIN EXTRACTS TO DIETS WITH DIFFERENT FORAGE TO CONCENTRATE RATIO ON In vitro RUMEN FERMENTATION AND METHANOGENESIS

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Y. Yogianto

2015-09-01

Full Text Available This experiment was aimed to investigate the effect of combining tannin and saponin extracts onruminal methane emission of diets with different proportion of forage to concentrate in the in vitrofermentation. The experiment was conducted in a factorial block design. The first factor was theproportion of forage:concentate in diets (70:30 and 30:70 and the second was addition of tannin andsaponin extracts (control, tannins, saponins, tannins + saponins in the dose of 2 mg/ml. Variablesobserved were gas production kinetics, methane production, dry matter digestibility (DMD, organicmatter digestibility (OMD and ammonia concentration. Results revealed that addition of tannins,saponins and their combination generally lowered total gas and methane production during 24 and 48 hof incubation period in both types of diets (P<0.05, but combination of tannins and saponins comparedwith their separated forms did not show any significant differences. The addition of tannins, saponinsand their combination reduced DMD, OMD and ammonia significantly (P<0.05. It can be concludedthat the addition of tannin, saponin and their combination at a dose of 2 mg/ml could reduce methaneemission but followed by a decline in the DMD, OMD and ammonia.

Influence of Tannin Extract and Yeast Extract on Color Preservation and Anthocyanin Content of Mulberry Wine.

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You, Yilin; Li, Na; Han, Xue; Guo, Jielong; Liu, Guojie; Huang, Weidong; Zhan, Jicheng

2018-04-01

The color of mulberry wine is extremely unstable in processing and aging. This paper investigates the effects of tannin extract and yeast extract on the color and color-preserving characteristics of mulberry wine made from the Dashi cultivar. The results showed that the maximum absorption wavelength in both tannin extract and yeast extract groups changed generating the red shift effect. The color of the tannin extract maintained a good gloss in the first 4 months, while the yeast extract group showed remarkable color preservation for the first 3 months. The total anthocyanin and cyanidin-3-rutinoside contents in both experiment groups were significantly higher than that of the control group, thus proving that tannin extract and yeast extract both exert a remarkably positive effect on preserving the color of mulberry wine during its aging. Moreover, sensory analysis indicated that the quality of mulberry wine treated with tannin extract was significantly higher than that of the control. The distinct color of mulberry wine is one of the foremost qualities that imprints on consumers' senses, but it is extremely unstable in processing and aging. However, the color protection of mulberry wine was not studied previously. In this study, we found that tannin extract and yeast extract both exert a remarkably positive effect on preserving the color of mulberry wine during aging. The study is of great significance as a guide to improving the color stability of mulberry wine, thereby also improving and promoting the development of the mulberry deep processing industry. © 2018 Institute of Food Technologists®.

Evaluation of antibacterial properties of tannins isolated from ...

African Journals Online (AJOL)

SERVER

2007-08-06

Aug 6, 2007 ... vity of leaf extract pf Eugenia uniflora and reported that tannins, alkaloids and glycosides were detected (Adebajo et al., 1983). African medicinal plants have been found to exert good in vivo antimicrobial activities and some active principles have been isolated (Damintoti et al., 2005). Examples are.

Ruminal Biohydrogenation Pattern of Poly-Unsaturated Fatty Acid as Influenced by Dietary Tannin

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Anuraga Jayanegara

2013-09-01

Full Text Available Large amounts of polyunsaturated fatty acids undergo transformation processes in the rumen through microbial biohydrogenation to form fatty acids with higher saturation degree. The respective process explains the high content of saturated fatty acids in products of ruminants and the potential risk of consumers’ health by consuming such products. Various nutritional approaches have been attempted to modulate biohydrogenation process in order to obtain healthier fatty acid profile from consumers’ perspective. The present paper is aimed to review the influence of dietary tannin, a naturally produced plant secondary compound, on the pattern of polyunsaturated fatty acids biohydrogenation occurring in the rumen. The effect of tannin on some key fatty acids involved in biohydrogenation process is presented together with the underlying mechanisms, particularly from up-to-date research results. Accordingly, different form of tannin as well as different level of the application are also discussed.

Towards high resolution ^1H NMR spectra of tannin colloidal aggregates

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Mirabel, M.; Glories, Y.; Pianet, I.; Dufourc, E. J.

1999-10-01

The time dependent colloidal formation of tannins in hydro-alcoholic medium has been studied by 1H-NMR. Line broadening observed with time can be cancelled by making use of magic angle sample spinning (MASS) thus yielding sharp lines that allow structural studies. We used as an example catechin, a constitutive monomer of Bordeaux young red wine tannins. Chemical shift variations of polyphenol protons allow monitoring the time course of aggregation. La formation de tanins colloïdaux au cours du temps, en milieu hydroalcoolique, a été suivie par RMN-^1H. Un élargissement marqué des résonances est observé et peut être supprimé par la rotation de l'échantillon à l'angle magique ce qui ouvre tout un champ d'études structurales sur ces composés colloïdaux. L'exemple proposé est celui de la catéchine, monomère constitutif de tannins présents en grande quantité dans les vins rouges jeunes de Bordeaux. Des variations du déplacement chimique de certains protons polyphénoliques permettent de suivre l'évolution temporelle de l'agrégation.

Study of the Qualitative and Semi-quantitative Analysis of Grape Seed Extract by HPLC

OpenAIRE

Sorolla, Sílvia; Flores, Antònia; Canals Parelló, Trini; Cantero Gómez, María Rosa; Font Vallès, Joaquim; Ollé Otero, Lluís; Bacardit Dalmases, Anna

2018-01-01

The main aim of this study is to carry out a qualitative and semiquantitative analysis of tannin extracts as an alternative to the official analysis method ISO 14088 – IUC 32, so that a correlation between the two methods is established. From the point of view of the chemical composition, tannins are classified into two major groups: i) condensed tannins, also called flavanols or catechins, and ii) hydrolysable tannins, also called pyrogallic tannins. Today, the most widely used convent...

Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and β-glucan.

Science.gov (United States)

Mekoue Nguela, J; Poncet-Legrand, C; Sieczkowski, N; Vernhet, A

2016-11-01

At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored by binding experiments, ITC and DLS. Depending on the tannin structure, a different affinity between the polyphenols and the YPE was observed, as well as differences in the stability of the aggregates. This was attributed to the mean degree of polymerization of tannins in the polyphenol fractions and to chemical changes that occur during winemaking. Much lower affinities were found between polyphenols and polysaccharides, with different behaviors between mannoproteins and β-glucans. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immobilized Tannin from Sanseviera trifasciata on Carbon as Adsorbent For Iron(II in Polluted Water Source

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Irfan Hanafi Arif

2016-03-01

Full Text Available The organic-agricultural waste resulted from local farmer or community gardening recently paid public attention. The presence and easily grown of “Lidah Mertua” or Sanseviera trifasciata being focused on potency investigation for its prospecting application. It was reported contain some phenolic and also tannin extracted from aqueous solvents. This paper revealed recent investigation applying of its isolated tannin from leave part to modifying of activated carbon. The previous report published that carbon were able to adsorb some toxic heavy metals. However, it has some limitation including lower capacity adsorption. Impregnated or immobilized the tannin-isolated from S. trifasciata leaves was able to modify the carbon functionality, physical appearance, pores size, and it adsorption capacity. Both Langmuir and Freundlich adsorption mechanism model also disclosed the developed adsorbent mechanism of iron(II adsorption on the adsorbent tannin-immobolized on carbon. The real test using community well drilling water source also gave important finding on the concentration of iron(II contained on water source.

Conversion of Natural Tannin to Hydrothermal and Graphene-Like Carbons Studied by Wide-Angle X-ray Scattering.

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Jurkiewicz, Karolina; Hawełek, Łukasz; Balin, Katarzyna; Szade, Jacek; Braghiroli, Flavia L; Fierro, Vanessa; Celzard, Alain; Burian, Andrzej

2015-08-13

The atomic structure of carbon materials prepared from natural tannin by two different techniques, high-temperature pyrolysis and low-temperature hydrothermal carbonization, was studied by wide-angle X-ray scattering. The obtained diffraction data were converted to the real space representation in the form of pair distribution functions. The X-ray photoelectron spectroscopy measurements provided information about the chemical state of carbon in tannin-based materials that was used to construct final structural models of the investigated samples. The results of the experimental data in both reciprocal and real spaces were compared with computer simulations based on the PM7 semiempirical quantum chemical method. Using the collected detailed information, structural models of the tannin-based carbons were proposed. The characteristics of the investigated materials at the atomic level were discussed in relation to their preparation method. The rearrangement of the tannin molecular structure and its transformation to graphene-like structure was described. The structure of tannin-based carbons pyrolyzed at 900 °C exhibited coherently scattering domains about 20 Å in size, consisting of two defected atomic layers and resembling a graphene-like arrangement.

The impact of tannins on protein, dry matter, and energy digestion in moose (Alces alces)

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Donald E. Spalinger; W.B. Collins; Thomas A. Hanley; N.E. Cassara; A.M. Carnahan

2010-01-01

Recent work suggests that moose (Alces alces [L., 1758]) in the boreal ecoregion may be nutritionally limited by the availability of protein as a consequence of both low nitrogen (N) concentrations and high tannin levels in their principal foods. However, the ability of moose to digest protein in the presence of tannins is unknown. We undertook a...

Robust Ultraviolet-Visible (UV-Vis) Partial Least-Squares (PLS) Models for Tannin Quantification in Red Wine.

Science.gov (United States)

Aleixandre-Tudo, José Luis; Nieuwoudt, Helené; Aleixandre, José Luis; Du Toit, Wessel J

2015-02-04

The validation of ultraviolet-visible (UV-vis) spectroscopy combined with partial least-squares (PLS) regression to quantify red wine tannins is reported. The methylcellulose precipitable (MCP) tannin assay and the bovine serum albumin (BSA) tannin assay were used as reference methods. To take the high variability of wine tannins into account when the calibration models were built, a diverse data set was collected from samples of South African red wines that consisted of 18 different cultivars, from regions spanning the wine grape-growing areas of South Africa with their various sites, climates, and soils, ranging in vintage from 2000 to 2012. A total of 240 wine samples were analyzed, and these were divided into a calibration set (n = 120) and a validation set (n = 120) to evaluate the predictive ability of the models. To test the robustness of the PLS calibration models, the predictive ability of the classifying variables cultivar, vintage year, and experimental versus commercial wines was also tested. In general, the statistics obtained when BSA was used as a reference method were slightly better than those obtained with MCP. Despite this, the MCP tannin assay should also be considered as a valid reference method for developing PLS calibrations. The best calibration statistics for the prediction of new samples were coefficient of correlation (R 2 val) = 0.89, root mean standard error of prediction (RMSEP) = 0.16, and residual predictive deviation (RPD) = 3.49 for MCP and R 2 val = 0.93, RMSEP = 0.08, and RPD = 4.07 for BSA, when only the UV region (260-310 nm) was selected, which also led to a faster analysis time. In addition, a difference in the results obtained when the predictive ability of the classifying variables vintage, cultivar, or commercial versus experimental wines was studied suggests that tannin composition is highly affected by many factors. This study also discusses the correlations in tannin values between the methylcellulose and protein

Eco-dyeing using Tamarindus indica L. seed coat tannin as a natural mordant for textiles with antibacterial activity

OpenAIRE

Prabhu, K.H.; Teli, M.D.

2014-01-01

Tamarind seed coat tannin was extracted and its tannin class was determined. The extracted tannin was employed as a natural mordant alone and in combination with metal mordant namely copper sulphate for cotton, wool and silk fabrics and dyed using natural dyes namely turmeric and pomegranate rind. The colour strength, colour coordinates, wash and light fastness were evaluated and compared for all the three fabrics with and without mordanting. The pre-mordanted fabrics on dyeing gave better co...

Factors affecting levels of some phenolic compounds, digestibility, and nitrogen content of the mature leaves ofBarteria fistulosa (Passifloraceae).

Science.gov (United States)

Waterman, P G; Ross, J A; McKey, D B

1984-03-01

Levels of total phenolics, condensed tannins, acid detergent fiber, pepsin/cellulase digestibility, and nitrogen in mature leaves of 26 individuals of the ant-plant,Barteria fistulosa, have been determined. Analysis of the results in terms of the presence or absence of ants and the position of the branch from which the leaves were collected showed no relationship with concentrations of phenolics or fiber and only a weak relationship with digestibility and nitrogen. By contrast, light intensity strongly influenced levels of phenolics, notably condensed tannins, so that mature leaves of individuals growing in direct sunlight were less digestible and appeared to be of lower quality as food for herbivores than did mature leaves of individuals in shaded positions. Possible reasons for the variation in condensed tannin levels are discussed.

Curtimento de peles de peixe com taninos vegetal e sintético = Tanning fish skins using vegetable and synthetic tannins

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Ariana Martins Vieira

2008-07-01

Full Text Available No presente experimento objetivou-se avaliar a resistência das peles de peixes submetidas ao curtimento com taninos vegetal e sintético. As peles foram distribuídas em um delineamento inteiramente casualizado, com seis tratamentos aplicados na etapa decurtimento (T1 = 10% tanino vegetal; T2=10% tanino sintético; T3 = 5% tanino vegetal + 5% sintético; T4 = 12% tanino vegetal; T5 = 12% tanino sintético; T6 = 6% tanino vegetal + 6% sintético e dez repetições por tratamento, sendo o couro a unidade experimental.Para os testes de resistência à tração, alongamento e rasgamento, foi utilizado o dinamômetro EMIC. O curtimento com tanino vegetal, sintético e/ou sua combinação, assim como os níveis utilizados dentro de cada técnica de curtimento, interferiu no teste de tração, no entanto não influenciou No teste de alongamento e rasgamento progressivo. Portanto, a técnica de curtimento interfere na resistência dos couros de peixes. As peles de tilápia, quando curtidas e recurtidas apenas com tanino sintético, independentemente da concentração (10 ou 12%, apresentaram pior resistência à tração. Quando comparados com os que receberam 10% de taninos (vegetal e a combinação dos taninos, esses couros não apresentaram diferença na resistência.The objective of the present experiment was to evaluate the resistance of fish skins submitted to tanning using vegetable and synthetic tannins. Skins were distributed in a completelyrandomized design, with six treatments applied in the tanning stage (T1 = 10% vegetable tannin; T2 = 10% synthetic tannin; T3 = 5% vegetable tannin + 5% synthetic tannin; T4 = 12% vegetable tannin; T5 = 12% synthetic tannin; T6 = 6% vegetable tannin + 6% synthetic. Ten repetitions per treatment were conducted, and the leather was theexperimental unit. For the tests of tensile strength, lengthening and progressive tearing resistance, an EMIC dynamometer was used. Tanning with vegetable tannin, synthetic

Sequestration of soil nitrogen as tannin-protein complexes may improve the competitive ability of sheep laurel (Kalmia angustifolia) relative to black spruce (Picea mariana).

Science.gov (United States)

Joanisse, G D; Bradley, R L; Preston, C M; Bending, G D

2009-01-01

The role of litter tannins in controlling soil nitrogen (N) cycling may explain the competitive ability of Kalmia relative to black spruce (Picea mariana), although this has not been demonstrated experimentally. Here, the protein-precipitation capacities of purified tannins and leaf extracts from Kalmia and black spruce were compared. The resistance to degradation of tannin-protein precipitates from both species were compared by monitoring carbon (C) and N dynamics in humus amended with protein, purified tannins or protein-tannin precipitates. The purity of the precipitates was verified using solid-state (13)C nuclear magnetic resonance (NMR) spectra. The ability of mycorrhizal fungi associated with both species to grow on media amended with tannin-protein complexes as the principal N source was also compared. The protein precipitation capacity of Kalmia tannins was superior to those of black spruce. Humus amended with protein increased both mineral and microbial N, whereas humus amended with tannin-protein precipitates increased dissolved organic N. Mycorrhizal fungi associated with Kalmia showed better growth than those associated with black spruce when N was provided as tannin-protein precipitates. These data suggest that Kalmia litter increases the amount of soil N sequestered as tannin-protein complexes, which may improve the competitive ability of Kalmia relative to black spruce by favouring N uptake by mycorrhizas associated with the former.

FIA-FAAS method for tannin determination based on a precipitation reaction with hemoglobin

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Ferreira Edilene C.

2003-01-01

Full Text Available A flow system, coupled with flame atomic absorption spectrometry (FIA-FAAS, was developed for tannin determination in pigeon pea samples, exploring the precipitation reaction between tannins and proteins. Sample extracts obtained by sonication with a 50% (v/v methanol solution were introduced into the system and induced to react with a hemoglobin solution. The precipitate produced was retained on a filter located in the analytical flow. A reversed flow of 1% (w/v sodium dodecyl sulfate solution was used for solubilization of the precipitate from the filter and to conduct the tannin-hemoglobin complex to the FAAS, to quantify the iron ions present in the hemoglobin structure. A tannic acid solution was used to prepare the analytical curve. The proposed method allowed determination of 30 samples per hour, a standard deviation of 9.7% (n=10, and a quantification limit of 0.27 mg L-1 for tannic acid.

Verifying the botanical authenticity of commercial tannins through sugars and simple phenols profiles.

Science.gov (United States)

Malacarne, Mario; Nardin, Tiziana; Bertoldi, Daniela; Nicolini, Giorgio; Larcher, Roberto

2016-09-01

Commercial tannins from several botanical sources and with different chemical and technological characteristics are used in the food and winemaking industries. Different ways to check their botanical authenticity have been studied in the last few years, through investigation of different analytical parameters. This work proposes a new, effective approach based on the quantification of 6 carbohydrates, 7 polyalcohols, and 55 phenols. 87 tannins from 12 different botanical sources were analysed following a very simple sample preparation procedure. Using Forward Stepwise Discriminant Analysis, 3 statistical models were created based on sugars content, phenols concentration and combination of the two classes of compounds for the 8 most abundant categories (i.e. oak, grape seed, grape skin, gall, chestnut, quebracho, tea and acacia). The last approach provided good results in attributing tannins to the correct botanical origin. Validation, repeated 3 times on subsets of 10% of samples, confirmed the reliability of this model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of food tannins on certain aspects of iron metabolism : Part 3 -- Heme synthesis and haematopoiesis in normal and anemic rats

International Nuclear Information System (INIS)

Roy, S.N.; Mukherjee, S.

1979-01-01

Tannin from various fruits and vegetables at a dose level of 0.5 mg/kg wt/day helps approximately 65% recovery of the blood hemoglobin concentration in hemolytic anemic rats within 7 days resulting in normal levels of haematological parameters. While in vitro tannin at low doses (5-10 μg/mg protein) stimulates iron incorporation into protoporphyrin IX by rat liver subcellular fractions, at higher doses (15-40 μg/mg protein) it inhibits the heme synthesis in liver, the inhibition being complete at 40 μg/mg protein. In vivo studies indicate that the administration of tannin (0.5 mg/kg) exhibits significant increase in incorporation of label into hemin of anemic rats compared to that of anemic control and tannin-fed normal groups. In rats receiving supplements of tannin (0.5 mg/k.o.), incorporation of the label into hemin of anemic ones is comparatively greater when 59 Fe is given by intravenous route instead of oral administration of radio-iron. The total labelling of 59 Fe in red blood cells is significantly greater in tannin-fed anemic rats than anemic control. These results suggest that tannin (0.5 mg/kg) from fruits and vegetables may help iron utilization more effectively for greater haematopoiesis in hemolytic anemia. (auth.)

Influence of food tannins on certain aspects of iron metabolism : Part 3 -- Heme synthesis and haematopoiesis in normal and anemic rats

Energy Technology Data Exchange (ETDEWEB)

Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukherjee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

1979-06-01

Tannin from various fruits and vegetables at a dose level of 0.5 mg/kg wt/day helps approximately 65% recovery of the blood hemoglobin concentration in hemolytic anemic rats within 7 days resulting in normal levels of haematological parameters. While in vitro tannin at low doses (5-10 ..mu..g/mg protein) stimulates iron incorporation into protoporphyrin IX by rat liver subcellular fractions, at higher doses (15-40 ..mu..g/mg protein) it inhibits the heme synthesis in liver, the inhibition being complete at 40 ..mu..g/mg protein. In vivo studies indicate that the administration of tannin (0.5 mg/kg) exhibits significant increase in incorporation of label into hemin of anemic rats compared to that of anemic control and tannin-fed normal groups. In rats receiving supplements of tannin (0.5 mg/k.o.), incorporation of the label into hemin of anemic ones is comparatively greater when /sup 59/Fe is given by intravenous route instead of oral administration of radio-iron. The total labelling of /sup 59/Fe in red blood cells is significantly greater in tannin-fed anemic rats than anemic control. These results suggest that tannin (0.5 mg/kg) from fruits and vegetables may help iron utilization more effectively for greater haematopoiesis in hemolytic anemia.

Total phenolics, flavonoids, tannins and antioxidant activity of lima beans conserved in a Brazilian Genebank

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Tânia da Silveira Agostini-Costa

2015-02-01

Full Text Available The objective of this study was to characterize for the first time polyphenols and DPPH (2-diphenyl-1-picryhydrazyl radical antioxidant activity in commonly cultivated accessions of Phaseolus lunatus from an ex situ germplasm collection maintained by Embrapa, in Brazil. Furthermore, the study aimed to detect changes in total polyphenols, total flavonoids and condensed tannin for the same accessions after regeneration in a greenhouse. The results showed the diversity of the lima bean collection for phenolic compounds, which were strongly correlated with antioxidant activity. Lima beans accessions with the highest polyphenols and antioxidant activity were those with colored seeds. Conservation through cold storage of P. lunatus seeds in a cold chamber in the germplasm collection did not necessarily affect phenolic compounds. Variations observed in values after regeneration seeds may be mainly results of biotic and abiotic factors, including not only cultivar, but also environmental conditions. This study suggests that polyphenols in the lima beans present antioxidant activity, with possible beneficial effects for human health. It was expected that the potential of this tasty legume can be also used as a functional food crop and/or as a new ingredient in gastronomy.

Fatty acid profile in the ruminal fluid and in the m. longissimus dorsi of lambs fed herbage or concentrate with or without tannins

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Alessandro Priolo

2010-01-01

Full Text Available Twenty-eight male lambs were divided into two groups at age 45 d. Fourteen lambs were given fresh herbage (vetch; the remaining lambs were fed a concentrate-based diet. Within each treatment, seven lambs received a supplementation of quebracho tannins. At slaughter (age 105 d the ruminal content and the muscle longissimus dorsi (LD were collected. Ruminal fluid and LD fatty acid composition was determined by gas chromatography. Among the concentrates-fed lambs, tannins supplementation reduced (P < 0.05 the concentration of C18:0 (- 49 % and increased vaccenic acid (VA; + 69 % in the ruminal fluid. When tannins were included into the concentrate, the LD contained double levels of rumenic acid (RA as compared to the LD of the lambs fed the tannins-free concentrate (0.96 vs. 0.46 % of total extracted fatty acids, respectively; P < 0.05. The concentration of PUFA was higher (P < 0.05 and SFA (P < 0.01 lower in the LD from lambs fed the tannin diets as compared to the animals receiving the tannin-free diets. In conclusion, tannins reduce the biohydrogenation of the PUFA in the rumen. This implies that tannins supplementation could be a strategy to increase the RA and PUFA content and to reduce the SFA into ruminant meats.

CONDENSATION OF WATER VAPOR IN A VERTICAL TUBE CONDENSER

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Jan Havlík

2015-10-01

Full Text Available This paper presents an analysis of heat transfer in the process of condensation of water vapor in a vertical shell-and-tube condenser. We analyze the use of the Nusselt model for calculating the condensation heat transfer coefficient (HTC inside a vertical tube and the Kern, Bell-Delaware and Stream-flow analysis methods for calculating the shell-side HTC from tubes to cooling water. These methods are experimentally verified for a specific condenser of waste process vapor containing air. The operating conditions of the condenser may be different from the assumptions adopted in the basic Nusselt theory. Modifications to the Nusselt condensation model are theoretically analyzed.

Analysis of Leucaena mimosine, Acacia tannins and total phenols by near infrared reflectance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Prasad, M N.V. [Hyderabad Univ. (India). Dept. of Plant Sciences

1995-11-01

The mimosine contents of Leucaena foliage, Acacia tannins and total phenols from leaf, bark and pod were analyzed by a near infrared relectance spectrophotometer (Compscan 3000). A calibration equation (linear summation regression) was developed with near infrared spectral analysis software, using 30 spectra from old and young leaves of Leucaena and 23 spectra from different samples of Acacia. The near infrared analyzer calculated that the percentages of mimosine, total phenols and tannins are closely comparable to laboratory results. (author)

QUALITATIVE AND QUANTITATIVE STUDY OF OENOTHERA ROSEA TANINOS L ' HERO . EX AITON

OpenAIRE

Kasay, M. I.; Huamán, J.; Guerrero, M.

2014-01-01

The present study aims at evaluating the polyphenolic compounds of plant Oenothera rosea L' Hér. Ex Aiton in branches and leaves of five different methods. Phytochemical analysis for the abundance of tannins which are of great industrial importance is determined. It identifies and classifies tannins Oenothera rosea L' Hér. Ex Aiton , finding the presence of hydrolysable tannins and condensed . Deepened in valuing different types of tannins found , using methods Lowenthal and Folin - Ciocalteu...

Steam condenser

International Nuclear Information System (INIS)

Masuda, Fujio

1980-01-01

Purpose: To enable safe steam condensation by providing steam condensation blades at the end of a pipe. Constitution: When high temperature high pressure steam flows into a vent pipe having an opening under water in a pool or an exhaust pipe or the like for a main steam eacape safety valve, non-condensable gas filled beforehand in the steam exhaust pipe is compressed, and discharged into the water in the pool. The non-condensable gas thus discharged from the steam exhaust pipe is introduced into the interior of the hollow steam condensing blades, is then suitably expanded, and thereafter exhausted from a number of exhaust holes into the water in the pool. In this manner, the non-condensable gas thus discharged is not directly introduced into the water in the pool, but is suitable expanded in the space of the steam condensing blades to suppress extreme over-compression and over-expansion of the gas so as to prevent unstable pressure vibration. (Yoshihara, H.)

The colloidal state of tannins impacts the nature of their interaction with proteins: the case of salivary proline-rich protein/procyanidins binding.

Science.gov (United States)

Cala, Olivier; Dufourc, Erick J; Fouquet, Eric; Manigand, Claude; Laguerre, Michel; Pianet, Isabelle

2012-12-18

While the definition of tannins has been historically associated with its propensity to bind proteins in a nonspecific way, it is now admitted that specific interaction also occurs. The case of the astringency perception is a good example to illustrate this phenomenon: astringency is commonly described as a tactile sensation induced by the precipitation of a complex composed of proline-rich proteins present in the human saliva and tannins present in beverages such as tea or red wines. In the present work, the interactions between a human saliva protein segment and three different procyanidins (B1, B3, and C2) were investigated at the atomic level by NMR and molecular dynamics. The data provided evidence for (i) an increase in affinity compared to shortest human saliva peptides, which is accounted for by protein "wraping around" the tannin, (ii) a specificity in the interaction below tannin critical micelle concentration (CMC) of ca. 10 mM, with an affinity scale such that C2 > B1 > B3, and (iii) a nonspecific binding above tannin CMC that conducts irremediably to the precipitation of the tannins/protein complex. Such physicochemical findings describe in accurate terms saliva protein-tannin interactions and provide support for a more subtle description by oenologists of wine astringency perception in the mouth.

Preventing freezing of condensate inside tubes of air cooled condenser

International Nuclear Information System (INIS)

Joo, Jeong A; Hwang, In Hwan; Lee, Dong Hwan; Cho, Young Il

2012-01-01

An air cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred

Condensate subcooling near tube exit during horizontal in-tube condensation

International Nuclear Information System (INIS)

Hashizume, K.; Abe, N.; Ozeki, T.

1992-01-01

In-tube condensation is encountered in various applications for heat exchangers, such as domestic air-conditioning equipment, industrial air-cooled condensers, and moisture separator reheaters (MSRs) for nuclear power pants. Numerous research work has been conducted to predict the condensation heat transfer coefficient, and we have now enough information for thermal design of heat exchangers with horizontal in-tube condensation. Most of the research is analytical and/or experimental work in the annular or stratified flow regime, or experimental work on bulk condensation, i.e., from saturated vapor to complete condensation. On the other hand, there exist few data about the heat transfer phenomena in the very lower-quality region near the tube exit. The purpose of this paper is to clarify the condensation heat transfer phenomena near the tube exit experimentally and analytically, and to predict the degree of condensate subcooling

Effect of tannins and saponins in Samanea saman on rumen environment, milk yield and milk composition in lactating dairy cows.

Science.gov (United States)

Anantasook, N; Wanapat, M; Cherdthong, A; Gunun, P

2015-04-01

The objective of this study was to investigate the effects of tannins and saponins in Samanea saman on rumen fermentation, milk yield and milk composition in lactating dairy cows. Four multiparous early-lactating dairy cows (Holstein-Friesian cross-bred, 75%) with an initial body weight (BW) of 405 ± 40 kg and 36 ± 8 day in milk were randomly assigned to receive dietary treatments according to a 4 × 4 Latin square design. The four dietary treatments were unsupplemented (control), supplemented with rain tree pod (S. saman) meal (RPM) at 60 g/kg, supplemented with palm oil (PO) at 20 g/kg, and supplemented with RPM at 60 g/kg and PO at 20 g/kg (RPO), of total dry matter (DM) intake. Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2, and chopped 30 g/kg of urea-treated rice straw was fed ad libitum. The RPM contained condensed tannins and crude saponins at 88 and 141 g/kg of DM respectively. It was found that supplementation with RPM and/or PO to dairy cows diets did not show negative effect on ruminal pH, blood urea nitrogen and milk urea nitrogen concentration (p > 0.05). However, supplementation with RPM resulted in lower ammonia nitrogen (NH3 -N) concentration (p rumen environment and increased milk yield, content of milk protein and milk fat. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Three-dimensional structure and dynamics of wine tannin-saliva protein complexes. A multitechnique approach.

Science.gov (United States)

Simon, Cécile; Barathieu, Karine; Laguerre, Michel; Schmitter, Jean-Marie; Fouquet, Eric; Pianet, Isabelle; Dufourc, Erick J

2003-09-09

The interactions between the B3 (catechin-4alpha,8-catechin) red wine tannin and the human salivary protein fragment IB7(14) (SPPGKPQGPPPQGG) were monitored by (1)H magic angle spinning NMR, circular dichroism, electrospray ionization mass spectrometry, and molecular modeling. It is found that the secondary structure of IB7(14) is made of a type II helix (collagen helix) and random coil. The central glycine 8 appears to act as a flexible rotula separating two helix II regions. Three tannin molecules tightly complex the peptide, without modifying its secondary structure, but seem to reduce its conformational dynamics. The binding dissociation constant is in the millimolar range. B3 tannins with a "tweezers" conformation bind to the hydrophilic side of the saliva peptide, suggesting that the principal driving forces toward association are governed by hydrogen bonding between the carbonyl functions of proline residues and both the phenol and catechol OH groups. These findings are further discussed in the frame of an astringency phenomenon.

Glucose, fructose and sucrose increase the solubility of protein-tannin complexes and at high concentration, glucose and sucrose interfere with bisulphite bleaching of wine pigments.

Science.gov (United States)

Harbertson, James F; Yuan, Chunlong; Mireles, Maria S; Hanlin, Rachel L; Downey, Mark O

2013-05-01

Wines were modified with increasing sugar concentrations and decreasing tannin concentrations and analysed by a combination of protein precipitation and bisulphite bleaching. Increasing sugar concentration decreased the precipitation of tannin and protein-precipitable polymeric pigments (PPP). The use of a hydrogen bond disruptor (urea) to reduce protein-tannin and protein-pigment complex formation showed that the effect of sugar concentration occurred by increasing the solubility of the tannin-protein complex, not by interfering with protein-tannin complex formation. By increasing the solubility of pigment-protein complexes, non-protein-precipitable polymeric pigments (nPPP) appeared to increase. There was also an increase in total polymeric pigments at each tannin concentration with increasing glucose and sucrose concentration, indicating that sugar concentration might also affect bisulphite bleaching of wine pigments. While a significant effect of sugar concentration on tannin-protein complex solubility was observed, these effects were greatest at sugar concentrations far in excess of normal wine making conditions. Under normal wine making conditions, sugar concentration will have a negligible effect on protein-precipitable tannin, PPP and nPPP concentrations. Copyright © 2012 Elsevier Ltd. All rights reserved.

The effects of seasonal climate changes in the caatinga on tannin levels in Myracrodruon urundeuva (Engl. Fr. All. and Anadenanthera colubrina (Vell. Brenan

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Júlio M. Monteiro

Full Text Available The influence of seasonal climatic changes on tannin concentrations was examined in two caatinga (semi-arid plant species (Myracrodruon urundeuva (Engl. Fr. All. and Anadenanthera colubrina (Vell. Brenan. The Folin-Ciocalteau method was used to quantify total phenols, and the casein precipitation method was used for tannins. In general, there is a close relationship between tannin levels and rainfall, although species seem to adopt different strategies of tannin compound production in response to periods of drought and rainfall in the caatinga.

Stability and oxidation products of hydrolysable tannins in basic conditions detected by HPLC/DAD-ESI/QTOF/MS.

Science.gov (United States)

Tuominen, Anu; Sundman, Terhi

2013-01-01

Hydrolysable tannins occur in plants that are used for food or medicine by humans or herbivores. Basic conditions can alter the structures of tannins, that is, the oxidation of phenolic groups can lead to the formation of toxic quinones. Previously, these labile quinones and other oxidation products have been studied with colorimetric or electron paramagnetic resonance methods, which give limited information about products. To study the stability and oxidation products of hydrolysable tannins in basic conditions using HPLC with a diode-array detector (DAD) combined with electrospray ionisation (ESI) and quadrupole time-of-flight (QTOF) MS. Three galloyl glucoses, four galloyl derivatives with different polyols and three ellagitannins were purified from plants. The incubation reactions of tannins were monitored by HPLC/DAD at five pH values and in reduced oxygen conditions. Reaction products were identified based on UV spectra and mass spectral fragmentation obtained with the high-resolution HPLC/DAD-ESI/QTOF/MS. The use of a base-resistant HPLC column enabled injections without the sample pre-treatment and thus detection of short-lived products. Hydrolysable tannins were unstable in basic conditions and half-lives were mostly less than 10 min at pH 10. Degradation rates were faster at pH 11 but slower at milder pH. The HPLC analyses revealed that various products were formed and identified to be the result of hydrolysis, deprotonation and oxidation. Interestingly, the main hydrolysis product was ellagic acid; it was also formed from galloyl glucoses that do not contain oxidatively coupled galloyl groups in their initial structures. HPLD/DAD-ESI/QTOF/MS was an efficient method for the identification of polyphenol oxidation products and showed how different pH conditions determine the fate of hydrolysable tannins. Copyright © 2013 John Wiley & Sons, Ltd.

Feed resource selection of Criollo goats artificially infected with Haemonchus contortus: nutritional wisdom and prophylactic self-medication.

Science.gov (United States)

Ventura-Cordero, J; González-Pech, P G; Jaimez-Rodriguez, P R; Ortiz-Ocampo, G I; Sandoval-Castro, C A; Torres-Acosta, J F J

2018-06-01

Previous cafeteria studies suggested that a moderate natural gastrointestinal nematode (GIN) infection did not modify the resource selection of adult Criollo goats towards tannin-rich plants compared with worm-free goats. A higher infection with Haemonchus contortus could trigger a change in the resource selection behaviour towards tannin-rich foliage. Alternatively, goats might select plant species solely to meet their nutritional requirements. A cafeteria study investigated the effect of a high artificial infection with H. contortus on the feed resource selection of goats. Adult Criollo goats (37.5±4.8 kg BW) with browsing experience were distributed in two groups: the infected group (IG) with six animals artificially infected with H. contortus (6000 L3/animal); and the non-infected group (NIG) with six animals maintained worm-free. The experiment included two 5-day periods with additional 5-day adaptation period. In the first period, animals were offered foliage of five plant species with a decreasing gradient of condensed tannins (CT) (Mimosa bahamensis, Gymnopodium floribundum, Havardia albicans, Acacia pennatula, Lysiloma latisiliqum), and three plant species with negligible CT content (Leucaena leucocephala, Piscidia piscipula and Brosimum alicastrum). In the second period the foliage of B. alicastrum was withdrawn. A grain-based concentrate feed was offered daily at 1% BW in DM basis. Dry matter and nutrient intake was determined. Foliage selection of each experimental group was determined using the Chesson selection index. The H. contortus egg count per gram of faeces (EPG) was determined for infected goats twice daily. Chesson index showed a similar pattern of foliage selection on periods 1 and 2. Mean EPG of goats in IG was 2028±259 EPG during period 1 and 1 293±198 EPG during period 2 (P>0.05). During period 1, the selection pattern was highest for B. alicastrum (tannin-free), followed by a tannin-rich plant (M. bahamensis). These two plants remained

Nanocrystalline TiO{sub 2} photosensitized with natural polymers with enhanced efficiency from 400 to 600nm

Energy Technology Data Exchange (ETDEWEB)

Espinosa, Rodolfo; Zumeta, Inti; Gonzalez, Bernardo; Docteur, Sergilus; Vigil, Elena [Institute of Materials and Reagents, Havana University, C. Habana 10400 (Cuba); Santana, Jorge L.; Martinez-Luzardo, Francisco [Higher Education Institute for Nuclear Science and Technology, Habana (Cuba)

2005-01-31

TiO{sub 2} sensitization for solar applications requires not only efficient but also stable and inexpensive sensitizers. Different condensed tannins extracted from bark wastes of tropical wood trees were studied as possible sensitizers of TiO{sub 2}. These natural polymers adhere strongly to the TiO{sub 2} even from aqueous solutions. Absorption spectra are presented for 1mM aqueous sensitizing solutions prepared with lyophilized condensed tannins which absorb light in the visible range. Spectral photocurrent measurements and I-V characterization show that no bias is required for electron injection to the TiO{sub 2} from all studied condensed tannins. Incident photon to current efficiency (IPCE) analysis indicates that surface complexation originates absorption bands with different electron injection efficiencies. These play a dominant role in determining IPCE spectral shape. We propose that surface modification by the sensitizer changes the surface trap density, thereby decreasing recombination losses.

Use of non-Saccharomyces yeasts and oenological tannin in red winemaking: Influence on colour, aroma and sensorial properties of young wines.

Science.gov (United States)

Chen, Kai; Escott, Carlos; Loira, Iris; Del Fresno, Juan Manuel; Morata, Antonio; Tesfaye, Wendu; Calderon, Fernando; Suárez-Lepe, Jose Antonio; Han, Shunyu; Benito, Santiago

2018-02-01

Today, many non-Saccharomyces strains have been verified can be positive for the development of wine anthocyanin and aroma in different fermentation scenarios. Moreover, oenological tannins are widely used in wine industry to improve the colour profile and aroma complexity. The aim of this work is to analyze the fermentation characters of non-Saccharomyces strains and investigate the effects of pre-fermentative addition of oenological tannins on the wine components as well as sensory properties. For this purpose, five selected non-Saccharomyces strains and grape seed tannin were used to carry out the different fermentation trials. As a result, the grape seed tannin were less likely to influence growth kinetics of non-Saccharomyces strains. Schizosaccharomyces pombe has been proved can be effective to reduce the malic acid content while increase the level of vinylphenolic pyranoanthocyanin, which is positive for wine colour stability. Pre-fermentative use of oenological tannin was verified could be beneficial for the wines fermented with non-Saccharomyces regarding the improvement of wine colour, anthocyanin composition and the complexity of volatile compounds. Nevertheless, sensory analysis showed that oenological tannin could be less effective to modify the aroma impression of non-Saccharomyces wines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationship between color and tannin content in sorghum grain: application of image analysis and artificial neural network

Directory of Open Access Journals (Sweden)

M Sedghi

2012-03-01

Full Text Available The relationship between sorghum grain color and tannin content was reported in several references. In this study, 33 phenotypes of sorghum grain differing in seed characteristics were collected and analyzed by Folin-Ciocalteu method. A computer image analysis method was used to determine the color characteristics of all 33 sorghum phenotypes. Two methods of multiple linear regression and artificial neural network (ANN models were developed to describe tannin content in sorghum grain from three input parameters of color characteristics. The goodness of fit of the models was tested using R², MS error, and bias. The computer image analysis technique was a suitable method to estimate tannin through sorghum grain color strength. Therefore, the color quality of the samples was described according three color parameters: L* (lightness, a* (redness - from green to red and b* (blueness - from blue to yellow. The developed regression and ANN models showed a strong relationship between color and tannin content of samples. The goodness of fit (in terms of R², which corresponds to training the ANN model, showed higher accuracy of prediction of ANN compared with the equation established by the regression method (0.96 vs. 0.88. The ANN models in term of MS error showed lower residuals distribution than that of regression model (0.002 vs. 0.006. The platform of computer image analysis technique and ANN-based model may be used to estimate the tannin content of sorghum.

Proanthocyanadin (condensed tannin) content of Brachystegia ...

African Journals Online (AJOL)

The higher contents of PA in the leaves that were harvested when mature than in young leaves could explain why animals prefer eating young rather than mature leaves of B. spiciformis. Keywords: browse legume, proanthocyanidins n-butanol, stages. African Journal of Range & Forage Science 2006, 23(3): 197–200 ...

Biophysical studies of interaction between hydrolysable tannins isolated from Oenothera gigas and Geranium sanguineum with human serum albumin.

Science.gov (United States)

Sekowski, Szymon; Ionov, Maksim; Kaszuba, Mateusz; Mavlyanov, Saidmukhtar; Bryszewska, Maria; Zamaraeva, Maria

2014-11-01

Tannins, secondary plant metabolites, possess diverse biological activities and can interact with biopolymers such as lipids or proteins. Interactions between tannins and proteins depend on the structures of both and can result in changes in protein structure and activity. Because human serum albumin is the most abundant protein in plasma and responsible for interactions with important biological compounds (e.g. bilirubin) and proper blood pressure, therefore, it is very important to investigate reactions between HSA and tannins. This paper describes the interaction between human serum albumin (HSA) and two tannins: bihexahydroxydiphenoyl-trigalloylglucose (BDTG) and 1-O-galloyl-4,6-hexahydroxydiphenoyl-β-d-glucose (OGβDG), isolated from Geranium sanguineum and Oenothera gigas leafs, respectively. Optical (spectrofluorimetric) and chiral optical (circular dichroism) methods were used in this study. Fluorescence analysis demonstrated that OGβDG quenched HSA fluorescence more strongly than BDTG. Both OGβDG and BDTG formed complexes with albumin and caused a red shift of the fluorescence spectra but did not significantly change the protein secondary structure. Our studies clearly demonstrate that the tested tannins interact very strongly with human serum albumin (quenching constant K=88,277.26±407.04 M(-1) and K=55,552.67±583.07 M(-1) respectively for OGβDG and BDTG) in a manner depending on their chemical structure. Copyright © 2014 Elsevier B.V. All rights reserved.

Tannin degradation by a novel tannase enzyme present in some Lactobacillus plantarum strains.

Science.gov (United States)

Jiménez, Natalia; Esteban-Torres, María; Mancheño, José Miguel; de Las Rivas, Blanca; Muñoz, Rosario

2014-05-01

Lactobacillus plantarum is frequently isolated from the fermentation of plant material where tannins are abundant. L. plantarum strains possess tannase activity to degrade plant tannins. An L. plantarum tannase (TanBLp, formerly called TanLp1) was previously identified and biochemically characterized. In this study, we report the identification and characterization of a novel tannase (TanALp). While all 29 L. plantarum strains analyzed in the study possess the tanBLp gene, the gene tanALp was present in only four strains. Upon methyl gallate exposure, the expression of tanBLp was induced, whereas tanALp expression was not affected. TanALp showed only 27% sequence identity to TanBLp, but the residues involved in tannase activity are conserved. Optimum activity for TanALp was observed at 30°C and pH 6 in the presence of Ca(2+) ions. TanALp was able to hydrolyze gallate and protocatechuate esters with a short aliphatic alcohol substituent. Moreover, TanALp was able to fully hydrolyze complex gallotannins, such as tannic acid. The presence of the extracellular TanALp tannase in some L. plantarum strains provides them an advantage for the initial degradation of complex tannins present in plant environments.

The effect of tannin-rich feeds on gas production and microbial ...

African Journals Online (AJOL)

Lindela

The effect of tannin with and without polyethylene glycol on ... In our previous studies it was demonstrated that Menz sheep given oilseed cake following the .... fraction than A. nilotica would explain the superior potential degradability ascribed ...

Pentaclethra macroloba tannins fractions active against methicillin-resistant staphylococcal and Gram-negative strains showing selective toxicity

Directory of Open Access Journals (Sweden)

Ivana Correa Ramos Leal

2011-12-01

Full Text Available The ethanol extract of the vegetal species Pentaclethra macroloba (Willd. Kuntze, Fabaceae, was fractioned and the antibacterial activity was determined. The active ethyl acetate (ea fraction showed activity against Gram-positive (Staphylococcus spp. and Enterococcus spp. and Gram-negative (Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella pneumoniae multiresistant bacteria. Gallic acid derivatives were identified as the main compounds in inactive subfractions from the ea fraction, while the active one afforded ellagic acid as the major constituent when submitted to acid hydrolysis reaction, which suggests the presence of hydrolysable tannins. The minimum bactericidal concentration analysis showed a bactericide mechanism of action for the tannin subfraction found. The antibacterial mechanism of action of the active tannin subfraction against S. aureus reference strains (ATCC 29213 e 33591 was proposed adopting an in vitro assay of protein synthesis inhibition. For this, bacterial cells were labeled with [35S] methionine in the presence of the subfraction. The protein synthesis inhibition was observed at 256 µg/mL of this subfraction. At this concentration it did not present cytotoxicity in eukaryotic cells by the neutral red technique, suggesting selective toxicity. The present study is the first in vitro investigation of the antibacterial properties of tannin fractions obtained from a polar extract of P. macroloba.

Pentaclethra macroloba tannins fractions active against methicillin-resistant staphylococcal and Gram-negative strains showing selective toxicity

Directory of Open Access Journals (Sweden)

Ivana Correa Ramos Leal

2011-08-01

Full Text Available The ethanol extract of the vegetal species Pentaclethra macroloba (Willd. Kuntze, Fabaceae, was fractioned and the antibacterial activity was determined. The active ethyl acetate (ea fraction showed activity against Gram-positive (Staphylococcus spp. and Enterococcus spp. and Gram-negative (Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella pneumoniae multiresistant bacteria. Gallic acid derivatives were identified as the main compounds in inactive subfractions from the ea fraction, while the active one afforded ellagic acid as the major constituent when submitted to acid hydrolysis reaction, which suggests the presence of hydrolysable tannins. The minimum bactericidal concentration analysis showed a bactericide mechanism of action for the tannin subfraction found. The antibacterial mechanism of action of the active tannin subfraction against S. aureus reference strains (ATCC 29213 e 33591 was proposed adopting an in vitro assay of protein synthesis inhibition. For this, bacterial cells were labeled with [35S] methionine in the presence of the subfraction. The protein synthesis inhibition was observed at 256 µg/mL of this subfraction. At this concentration it did not present cytotoxicity in eukaryotic cells by the neutral red technique, suggesting selective toxicity. The present study is the first in vitro investigation of the antibacterial properties of tannin fractions obtained from a polar extract of P. macroloba.

Water Condensation

DEFF Research Database (Denmark)

Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund

2014-01-01

The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

Turbidimetric and photometric determination of total tannins in tea using a micro-flow-batch analyzer.

Science.gov (United States)

Lima, Marcelo B; Andrade, Stéfani I E; Harding, David P; Pistonesi, Marcelo F; Band, Beatriz S F; Araújo, Mário C U

2012-01-15

Both turbidimetric and photometric determinations of total tannins in samples of green and black tea, using a micro-flow-batch analyzer (μFBA) were studied. The miniaturized system was formed using photocurable urethane-acrylate resin and ultraviolet lithography technique. The turbidimetric method was based on the precipitation reaction of Cu (II) with tannins in acetate medium at a pH of 4.5. The photometric method was based on the complexation reaction of tannins with ferrous tartrate. The turbidimetric μFBA was able to test 200 samples per hour. The photometric μFBA allowed 300 analyses per hour, generating 136μL of residue per analysis. The paired t test, at a 95% confidence level, showed no statistically significant differences between results obtained by both methods and the reference method. The urethane-acrylate μFBA maintained satisfactory physical and chemical properties, and represents an improvement over conventional flow-batch analyzer. Copyright © 2011 Elsevier B.V. All rights reserved.

Percentage Level of Tannin fur Rabbit for Leather Concerning Stitch Tearing Strength, Tearing Strength and Flexibility

OpenAIRE

Mustakim Mustakim; Aris Sri Widati; Lisa Purnaningtyas

2012-01-01

The purpose of this study was to find out the appropriate of tannin level for rabbit fur leather concerning stitch tearing strength, tearing strength, and flexibility. The result were expected to contribute good information for the society, leather craftsman, and further researchers about fur leather tanning especially rabbit fur leather with tannin concerning stitch tearing strength, tearing strength and flexibility. The material that used were 12 pieces of four months of rabbit skin. The re...

The green synthesis of gold nanoparticles using the ethanol extract pf black tea and its tannin free fraction

International Nuclear Information System (INIS)

Banoee, M.; Mokhtari, N.; Akhavan Sepahi, A.; Jafari Fesharaki, P.; Monsef-Esfahani, H. R.; Ehsanfar, Z.; Khoshayand, M. R.; Shahverdi, A. R.

2010-01-01

In this research the ethanol extract of black tea and its tannin free fraction used for green synthesis of gold nanoparticles. All the extracts were used separately for the synthesis of gold nanoparticles through the reduction of aqueous AuCl 4 - . Transmission electron microscopy and visible absorption spectroscopy confirmed the reduction of gold ions to gold nanoparticles. The ethanol extract of black tea and its tannin free ethanol extract produced gold nanoparticles in the size ranges of 2.5-27.5 nm and 1.25-17.5 nm with an average size of 10 nm and 3 nm, respectively. The prepared colloid gold nanoparticles, using the ethanol extract of black tea, did not show the appropriate stability during storage time (24 hours) at 4 d eg C . In contrast, gold colloids, which were synthesized by a tannin free fraction showed no particle aggregation during short and long storage times at the same conditions. To the best of our knowledge, this is the first report on the rapid synthesis of gold nanoparticles using ethanol extract of black tea and its tannin free fraction.

The influence of defoliation and moisture on the tannin and ...

African Journals Online (AJOL)

To determine whether tannin and total polyphenol contents of Portulacaria afra change owing to damage, different trees were subjected to three intensities of defoliation, namely, none, fifty and ninety per cent. In addition, the influence of an improved water supply through irrigation was determined. Results showed an initial ...

α-Glucosidase inhibitory hydrolyzable tannins from Eugenia jambolana seeds.

Science.gov (United States)

Omar, Raed; Li, Liya; Yuan, Tao; Seeram, Navindra P

2012-08-24

Three new hydrolyzable tannins including two gallotannins, jamutannins A (1) and B (2), and an ellagitannin, iso-oenothein C (3), along with eight known phenolic compounds were isolated from the seeds of Eugenia jambolana fruit. The structures were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for α-glucosidase inhibitory effects compared to the clinical drug acarbose.

Tannin Degradation by a Novel Tannase Enzyme Present in Some Lactobacillus plantarum Strains

Science.gov (United States)

Jiménez, Natalia; Esteban-Torres, María; Mancheño, José Miguel; de las Rivas, Blanca

2014-01-01

Lactobacillus plantarum is frequently isolated from the fermentation of plant material where tannins are abundant. L. plantarum strains possess tannase activity to degrade plant tannins. An L. plantarum tannase (TanBLp, formerly called TanLp1) was previously identified and biochemically characterized. In this study, we report the identification and characterization of a novel tannase (TanALp). While all 29 L. plantarum strains analyzed in the study possess the tanBLp gene, the gene tanALp was present in only four strains. Upon methyl gallate exposure, the expression of tanBLp was induced, whereas tanALp expression was not affected. TanALp showed only 27% sequence identity to TanBLp, but the residues involved in tannase activity are conserved. Optimum activity for TanALp was observed at 30°C and pH 6 in the presence of Ca2+ ions. TanALp was able to hydrolyze gallate and protocatechuate esters with a short aliphatic alcohol substituent. Moreover, TanALp was able to fully hydrolyze complex gallotannins, such as tannic acid. The presence of the extracellular TanALp tannase in some L. plantarum strains provides them an advantage for the initial degradation of complex tannins present in plant environments. PMID:24610854

Performance of evaporative condensers

Energy Technology Data Exchange (ETDEWEB)

Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

2001-07-01

Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

Application of the SPI (Saliva Precipitation Index) to the evaluation of red wine astringency.

Science.gov (United States)

Rinaldi, Alessandra; Gambuti, Angelita; Moio, Luigi

2012-12-15

The aim of this work was to evaluate the astringency of red wines by means of a SDS-PAGE based-method. The optimization of the in vitro assay, named SPI (Saliva Precipitation Index) that measured the reactivity of salivary proteins towards wine polyphenols, has been performed. Improvements included the choice of saliva:wine ratio, saliva typology (resting or stimulated saliva), and temperature of binding. The LOD (0.05 g/L of condensed tannin) and LOQ (0.1g/L of condensed tannin) for the binding reaction between salivary proteins and tannins added in white wine were also determined. Fifty-seven red wines were analysed by the optimised SPI, the Folin-Ciocalteu Index, the gelatine index, the content of total tannins and the sensory quantitative evaluation of astringency. A significant correlation between the SPI and the astringency of red wines was found (R(2)=0.969), thus indicating that this assay may be useful as estimator of astringency. Copyright © 2012 Elsevier Ltd. All rights reserved.

Condensation of steam

International Nuclear Information System (INIS)

Prisyazhniuk, V.A.

2002-01-01

An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and β-glucan

OpenAIRE

Mekoue Nguela, Julie; Poncet-Legrand, Celine; Sieczkowski, N.; Vernhet, Aude

2016-01-01

At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored b...

Modelling of condensation phenomena

International Nuclear Information System (INIS)

Jeong, Jae Jun; Chang, Won Pyo

1996-07-01

Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

Improved condenser design and condenser-fan operation for air-cooled chillers

International Nuclear Information System (INIS)

Yu, F.W.; Chan, K.T.

2006-01-01

Air-cooled chillers traditionally operate under head pressure control via staging constant-speed condenser fans. This causes a significant drop in their coefficient of performance (COP) at part load or low outdoor temperatures. This paper describes how the COP of these chillers can be improved by a new condenser design, using evaporative pre-coolers and variable-speed fans. A thermodynamic model for an air-cooled screw-chiller was developed, within which the condenser component considers empirical equations showing the effectiveness of an evaporative pre-cooler in lowering the outdoor temperature in the heat-rejection process. The condenser component also contains an algorithm to determine the number and speed of the condenser fans staged at any given set point of condensing temperature. It is found that the chiller's COP can be maximized by adjusting the set point based on any given chiller load and wet-bulb temperature of the outdoor air. A 5.6-113.4% increase in chiller COP can be achieved from the new condenser design and condenser fan operation. This provides important insights into how to develop more energy-efficient air-cooled chillers

Application of immobilized tannase from Aspergillus niger for the removal of tannin from myrobalan juice.

Science.gov (United States)

Srivastava, Anita; Kar, Rita

2010-10-01

Tannase produced optimally on an agroresidue by an Aspergillus niger isolate under submerged fermentation immobilized on sodium alginate beads with 93.6% efficiency was applied for tannin removal from myrobalan/aonla (Phyllanthus emblica) juice. The pH and temperature optima of the immobilized enzyme were found to be 5.4 and 40°C while the corresponding values of the soluble enzyme were 5.8 and 35°C. Maximum tannin removal of 73.6% was obtained at 40°C and 150 rpm in 180 min with 36.6 U/ml of immobilized enzyme while the same amount of the soluble enzyme removed 45.2% of tannin at 37°C and 150 rpm in the same time period. The immobilized beads could be used repeatedly till 7th cycle with 77% efficiency. When preserved at 6°C the beads retained 71.7% of enzyme activity after 60 days. Reduction in vitamin C content, which is responsible for antioxidant property of the fruit, was minimum at only 2% during the treatment.

Proceedings: Condenser technology conference

International Nuclear Information System (INIS)

Tsou, J.L.; Mussalli, Y.G.

1991-08-01

Seam surface condenser and associated systems performance strongly affects availability and heat rate in nuclear and fossil power plants. Thirty-six papers presented at a 1990 conference discuss research results, industry experience, and case histories of condenser problems and solutions. This report contains papers on life extension, performance improvement, corrosion and failure analysis, fouling prevention, and recommendation for future R ampersand D. The information represents recent work on condenser problems and solutions to improve the procurement, operation, and maintenance functions of power plant personnel. Several key points follow: A nuclear and a fossil power plant report show that replacing titanium tube bundles improves condenser availability and performance. One paper reports 10 years of experience with enhanced heat transfer tubes in utility condensers. The newly developed enhanced condenser tubes could further improve condensing heat transfer. A new resistance summation method improves the accuracy of condenser performance prediction, especially for stainless steel and titanium tubed condensers. Several papers describe improved condenser fouling monitoring techniques, including a review of zebra mussel issues

IMMOBILIZATION OF TANNIN ACYL HYDROLASE FROM ASPERGILLUS NIGER

OpenAIRE

B. Lenin Kumar*, N. Lokeswari and D. Sriramireddy

2013-01-01

ABSTRACT: Tannin acyl hydrolase, commonly referred to as tannase (E.C. 3.1.1.20), an inducible extra-cellular enzyme produced by a number of animals, plants and microbes. In this investigation, tannase production under solid-state fermentation by using Aspergillus niger and the waste residue of cashew husk was used as substrate for obtaining the desired fermented product. Microbial tannase is more stable than tannase from other sources like plants or animals. Tannase from fungal sources are r...

CT false-profile view of the hip: a reproducible method of measuring anterior acetabular coverage using volume CT data

International Nuclear Information System (INIS)

Needell, Steven D.; Borzykowski, Ross M.; Carreira, Dominic S.; Kozy, John

2014-01-01

To devise a simple, reproducible method of using CT data to measure anterior acetabular coverage that results in values analogous to metrics derived from false-profile radiographs. Volume CT images were used to generate simulated false-profile radiographs and cross-sectional false-profile views by angling a multiplanar reformat 115 through the affected acetabulum relative to a line tangential to the posterior margin of the ischial tuberosities. The anterolateral margin of the acetabulum was localized on the CT false-profile view corresponding with the cranial opening of the acetabular roof. Anterior center edge angle (CEA) was measured between a vertical line passing through the center of the femoral head and a line connecting the center of the femoral head with the anterior edge of the condensed line of the acetabulum (sourcil). Anterior CEA values measured on CT false-profile views of 38 symptomatic hips were compared with values obtained on simulated and projection false-profile radiographs. The CT false-profile view produces a cross-sectional image in the same obliquity as false-profile radiographs. Anterior CEA measured on CT false-profile views were statistically similar to values obtained with false-profile radiographs. CT technologists quickly mastered the technique of generating this view. Inter-rater reliability indicated this method to be highly reproducible. The CT false-profile view is simple to generate and anterior CEA measurements derived from it are similar to those obtained using well-positioned false-profile radiographs. Utilization of CT to assess hip geometry enables precise control of pelvic inclination, eliminates projectional errors, and minimizes limitations of image quality inherent to radiography. (orig.)

CT false-profile view of the hip: a reproducible method of measuring anterior acetabular coverage using volume CT data

Energy Technology Data Exchange (ETDEWEB)

Needell, Steven D.; Borzykowski, Ross M. [Boca Radiology Group, Boca Raton, FL (United States); Carreira, Dominic S.; Kozy, John [Broward Health Orthopedics and Sports Medicine, Fort Lauderdale, FL (United States)

2014-11-15

To devise a simple, reproducible method of using CT data to measure anterior acetabular coverage that results in values analogous to metrics derived from false-profile radiographs. Volume CT images were used to generate simulated false-profile radiographs and cross-sectional false-profile views by angling a multiplanar reformat 115 through the affected acetabulum relative to a line tangential to the posterior margin of the ischial tuberosities. The anterolateral margin of the acetabulum was localized on the CT false-profile view corresponding with the cranial opening of the acetabular roof. Anterior center edge angle (CEA) was measured between a vertical line passing through the center of the femoral head and a line connecting the center of the femoral head with the anterior edge of the condensed line of the acetabulum (sourcil). Anterior CEA values measured on CT false-profile views of 38 symptomatic hips were compared with values obtained on simulated and projection false-profile radiographs. The CT false-profile view produces a cross-sectional image in the same obliquity as false-profile radiographs. Anterior CEA measured on CT false-profile views were statistically similar to values obtained with false-profile radiographs. CT technologists quickly mastered the technique of generating this view. Inter-rater reliability indicated this method to be highly reproducible. The CT false-profile view is simple to generate and anterior CEA measurements derived from it are similar to those obtained using well-positioned false-profile radiographs. Utilization of CT to assess hip geometry enables precise control of pelvic inclination, eliminates projectional errors, and minimizes limitations of image quality inherent to radiography. (orig.)

DETERMINING LIGHTFASTNESS PROPERTIES OF VEGETABLE TANNINS AND CHEMICAL PROPERTIES OF THE LEATHERS TANNED WITH MODIFIED MIMOSA AND QUEBRACHO

Directory of Open Access Journals (Sweden)

OMUR Sukru

2016-05-01

Full Text Available The vegetable tannins are the oldest tanning agents used in leather industry. They give their natural character and colour to the leathers which they are applied to, but they have the disadvantage of colour change when they are exposed to light for prolonged times. In this study light fastness properties of leathers tanned with mimosa, quebracho, valonea and chestnut tannins were measured. Lightfastness properties of mimosa and quebracho tannins were found lower. Then these tannins were modified with sulphitation, novalac synthesis and sulphomethylation processes. Lightfastness and determination of volatile matter, determination of matter soluble in dichloromethane, determination of sulphated total ash and sulphated water-insoluble ash, determination of water soluble matter, water soluble inorganic matter and water soluble organic matter, determination of nitrogen content and hide substance, calculation of degree of tannage determination of formaldehyde content analyses were performed to the leathers tanned with modified mimosa and quebracho tannins. From comparison of results, it was understood that sulpmethylation process can be used for production of leathers with higher lightfastness and without major change on chemical properties. When chemical properties of leathers tanned with modified quebracho and mimosa are considered: volatile matter, sulphated total ash and sulphated water- insoluble ash, water soluble matter, water soluble inorganic matter and water soluble organic matter, hide substance and formaldehyde contents were found compatible with standard mimosa and quebracho. However degree of tannage and matter soluble in dichloromethane values were found lower, which means some enhancements in modification or fatliquoring process should be considered.

Condensate cleaning systems

International Nuclear Information System (INIS)

Yamamoto, Michiyoshi; Oosumi, Katsumi; Takashima, Yoshie; Mitani, Shinji.

1982-01-01

Purpose: To decrease the frequency for the backwash and regeneration operations due to the increase in the differential pressure resulted from claddings captured in a mixed floor type desalter, and decrease the amount of radioactive liquid wastes of claddings from the condensate systems by removing claddings with electromagnetic filters. Constitution: In an existent plant, a valves is disposed between a condensate pump and a mixed floor type desalter. A pipeway is branched from a condensate pipe between the condensate pipe and the valve, through which condensates are transferred by a pump to an electromagnetic filter such as of a high gradient type electromagntic filter to remove claddings, then returned to a condensate pipe between the valve and the mixed floor type desalter and, thereafter, are removed with ionic components in the mixed floor type desalter and fed to the reactor. (Yoshino, Y.)

Removal of Pb2+ from Water by Synthesized Tannin Resins from Invasive South African Trees

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Bamidele J. Okoli

2018-05-01

Full Text Available Contamination of water by Pb 2 + and the threat of invasive vegetation affects the quality and quantity of water accessible to all life forms and has become a primary concern to South Africa and the world at large. This paper synthesized, characterized, and evaluated the resins from tannin-rich invasive Acacia species as an environmentally benign Pb 2 + adsorbent. The analysis of the pore volume and surface area of the resins reveals a small pore dimension of 9 × 10−3 cc/g and large surface area (2.31–8.65 m2/g, presenting suitable physical parameters for adsorption of Pb 2 + . Langmuir model offers the best correlation data at pH 6 with maximum monolayer coverage capacity of 189.30, 105.70 and 98.82 mg/g for silver, black and green wattle tannin resins in aqueous solutions, respectively. The kinetic data suitably fits into a pseudo-second-order model, with the Dubinin–Radushkevich adsorption energy (E ≤ 7.07 KJ/mol and intra-particle diffusion model confirming an associated physisorption process within the bio-sorption system. The thermogravimetric analysis (TGA and Fourier-transform infrared (FT-IR data of the resins were informative of the high thermal stability and chelating functionality such as -OH and -NH2 responsible for the removal of Pb 2 + . All the resins showed good adsorption characteristics while silver wattle tannin resin has the best adsorption capacity compared to black and green wattle tannin resins. This study provides a prototype adsorbent from invasive plants for the removal of Pb 2 + in water.

Effect of addition of commercial grape seed tannins on phenolic composition, chromatic characteristics, and antioxidant activity of red wine.

Science.gov (United States)

Neves, Ana C; Spranger, Maria I; Zhao, Yuqing; Leandro, Maria C; Sun, Baoshan

2010-11-24

The effect of addition of grape seed tannins on the phenolic composition, chromatic characteristics, and antioxidant activity of red wine was studied. Two highly pure commercial grape seed tannins (GSE100 and GSE300) were selected, and their phenolic compositions were determined. Two types of red wines were made with Castelão/Tinta Miúda (3/2, w/w) grapevine varieties by fermentation on skin using two different maceration times, which correspond to the wines rich and poor in polyphenols, respectively. Each of these wines was used for experimentation with the addition of GSE100 and GSE300 before and immediately after alcoholic fermentation. Phenolic composition, chromatic characteristics, and antioxidant activity of the finished red wines were analyzed by HPLC-DAD, CIElab 76 convention, and DPPH radical test, respectively. The results showed that the addition of grape seed tannins had obvious effects of increasing color intensity and antioxidant activity only in the wines poor in polyphenols. Although GSE300 contained much higher amounts of di- and trimer procyanidins and a lower amount of polymeric proanthocyanidins, it provided effects of increasing the color intensity and antioxidant activity of the wines poor in polyphenols similar to those of GSE100. Furthermore, GSE100 released more gallic acid to wines than GSE300, although no gallic acid was detected in GSE100. Tannins added after alcoholic fermentation had a better effect on phenolic composition of red wine than tannins added before alcoholic fermentation.

Secondary Fitometabolitos that affect the nutritional value of Lotus corniculatus as forage for ruminant animals

OpenAIRE

Luz Elena Santacoloma Varón

2014-01-01

In the highlands of Bogota at 2600 masl, temperature 14°C and 1013 mm of precipitation, three plots have been furbished by modifying the physico- chemical conditions of the soil and planted the species Lotus corniculatus to evaluate content of condensed tannins, hydrolysable tannins, phenols, tannins that precipitate protein, saponins and alkaloids. The purpose was to determine the effect of soil conditions on the concentration of secondary phytobiomolecules. Analytical and instrumental techn...

Condensation coefficient of water in a weak condensation state

International Nuclear Information System (INIS)

Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

2008-01-01

The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

Condensation coefficient of water in a weak condensation state

Science.gov (United States)

Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

2008-07-01

The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

Hydrolyzable tannin analysis in food.

Science.gov (United States)

Arapitsas, Panagiotis

2012-12-01

The discovery of plant polyphenols in food is perhaps one of the biggest breakthroughs in modern food science. Plant polyphenols are known for their role in food quality and safety, since they contribute significantly to taste, flavour, colour, stability etc., while they are increasingly recognised as important factors in long-term health, contributing towards reducing the risk of chronic disease. Almost 200years ago, hydrolyzable tannins (HTs) were the first group of plant polyphenols subjected to analytical chemical research. Despite the lack of commercially available standards, food analysis research offers a wealth of papers dealing with extraction optimisation, identification and quantification of HTs. The object of this review is to summarise analytical chemistry applications and the tools currently used for the analysis of HTs in food. Copyright © 2012 Elsevier Ltd. All rights reserved.

Maintaining steam/condensate lines

International Nuclear Information System (INIS)

Russum, S.A.

1992-01-01

Steam and condensate systems must be maintained with the same diligence as the boiler itself. Unfortunately, they often are not. The water treatment program, critical to keeping the boiler at peak efficiency and optimizing operating life, should not stop with the boiler. The program must encompass the steam and condensate system as well. A properly maintained condensate system maximizes condensate recovery, which is a cost-free energy source. The fuel needed to turn the boiler feedwater into steam has already been provided. Returning the condensate allows a significant portion of that fuel cost to be recouped. Condensate has a high heat content. Condensate is a readily available, economical feedwater source. Properly treated, it is very pure. Condensate improves feedwater quality and reduces makeup water demand and pretreatment costs. Higher quality feedwater means more reliable boiler operation

Yield of tannin willows on ravine areas in the Central Forest Steppe

Energy Technology Data Exchange (ETDEWEB)

Sidorov, A I

1981-01-01

A note on the performance of 12 species of willow grown in a plantation on leached chernozem soils, to provide bark rich in tannins. The plantation was established by cuttings (25 cm long) at a spacing of 2.5 x 0.5 metres for the tree willows and 2.5 x 0.75 metres for the bush willows. Bark yields were determined at 7-8 years. The greatest yields were obtained from Salix smithiana, S. stipularis and S. acuminata: 12.0, 10.8 and 10.2 t/hectare respectively. Data on tannin yields are tabulated. Fellings for bark harvesting can be made every 5 years in plantations of bush willows and every 7 years in plantations of tree willows. The plantations can be used for 30 year with bush willows and for 50 years with tree willows.

Flavonoids and Tannins from Smilax china L. Rhizome Induce Apoptosis Via Mitochondrial Pathway and MDM2-p53 Signaling in Human Lung Adenocarcinoma Cells.

Science.gov (United States)

Fu, San; Yang, Yanfang; Liu, Dan; Luo, Yan; Ye, Xiaochuan; Liu, Yanwen; Chen, Xin; Wang, Song; Wu, Hezhen; Wang, Yuhang; Hu, Qiwei; You, Pengtao

2017-01-01

In vitro evidence indicates that Smilax china L. rhizome (SCR) can inhibit cell proliferation. Therefore, in the present study, we analyzed the effects in vitro of SCR extracts on human lung adenocarcinoma A549 cells. Our results showed that A549 cell growth was inhibited in a dose- and time-dependent manner after treatment with SCR extracts. Total flavonoids and total tannins from SCR induced A549 apoptosis in a dose-dependent manner, as shown by our flow cytometry analysis, which was consistent with the alterations in nuclear morphology we observed. In addition, the total apoptotic rate induced by total tannins was higher than the rate induced by total flavonoids at the same dose. Cleaved-caspase-3 protein levels in A549 cells after treatment with total flavonoids or total tannins were increased in a dose-dependent manner, followed by the activation of caspase-8 and caspase-9, finally triggering to PARP cleavage. Furthermore, total flavonoids and total tannins increased the expression of Bax, decreased the expression of Bcl-2, and promoted cytochrome [Formula: see text] release. Moreover, MDM2 and p-MDM2 proteins were decreased, while p53 and p-p53 proteins were increased, both in a dose-dependent manner, after A549 treatment with total flavonoids and total tannins. Finally, cleaved-caspase-3 protein levels in the total flavonoids or total tannins-treated H1299 (p53 null) and p53-knockdown A549 cells were increased. Our results indicated that total flavonoids and total tannins from SCR exerted a remarkable effect in reducing A549 growth through their action on mitochondrial pathway and disruption of MDM2-p53 balance. Hence, our findings demonstrated a potential application of total flavonoids and total tannins from SCR in the treatment of human lung adenocarcinoma.

Enhanced Condensation Heat Transfer

Science.gov (United States)

Rose, John Winston

The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.

Sorption of Tannin and Related Phenolic Compounds and Effects on Extraction of Soluble-N in Soil Amended with Several Carbon Sources

Directory of Open Access Journals (Sweden)

Javier M. Gonzalez

2012-02-01

Full Text Available Some tannins sorb to soil and reduce soluble-N. However, we know little about how they interact with organic amendments in soil. Soil (0–5 cm from plots, which were amended annually with various carbon substances, was treated with water (control or solutions containing tannins or related phenolic subunits. Treatments included a proanthocyanidin, catechin, tannic acid, β-1,2,3,4,6-penta-O-galloyl-D-glucose (PGG, gallic acid, and methyl gallate. We applied solutions of each of these materials to soil and measured soluble-C and -N in supernatants after application and following extraction with hot water (16 h, 80 °C. Sorption was low for non-tannin phenolics, methyl gallate, gallic acid, and catechin, and unaffected by amendment. Sorption of tannins, proanthocyanidin, tannic acid, and PGG, was higher and greater in plots amended with biosolids or manure. Extraction of soluble-N was not affected by amendment or by catechin, proanthocyanidin, or methyl gallate, but was reduced with PGG, tannic acid and gallic acid. Soil cation exchange capacity increased following treatment with PGG but decreased with gallic acid, irrespective of amendment. Tannins entering soil may thus influence soil organic matter dynamics and nutrient cycling but their impact may be influenced by the composition of soil organic matter.

Combined biodegradation and ozonation for removal of tannins and dyes for the reduction of pollution loads.

Science.gov (United States)

Kanagaraj, James; Mandal, Asit Baran

2012-01-01

Tannins and dyes pose major threat to the environment by generating huge pollution problem. Biodegradation of wattle extract, chrome tannin and dye compounds using suitable fungal culture namely Aspergillus niger, Penicillium sp. were carried out. In addition to these, ozone treatment was carried out to get higher degradation rate. The results were monitored by carrying out chemical oxygen demand (COD), total organic carbon (TOC), and UV-Vis analysis. The results showed that wattle extract (vegetable tannin) gave better biodegradation rate than dye and chromium compounds. Biodegradation plus ozone showed degradation rates of 92-95%, 94-95%, and 85-87% for the wattle extract, dyes, chromium compounds, respectively. UV-Vis showed that there were no peaks observed for biodegraded samples indicating better degradation rates as compared to the control samples. FT-IR spectra analysis suggested that the formation of flavanoid derivatives, chromic oxide and NH(2) compounds during degradation of wattle extract, chromium and dye compounds, respectively, at the peaks of 1,601-1,629 cm(-1), 1,647 cm(-1), and 1,610-1,680 cm(-1). The present investigation shows that combination of biodegradation with ozone is the effective method for the removal of dyes and tannins. The biodegradation of the said compounds in combination with ozonation showed better rate of degradation than by chemical methods. The combination of biodegradation with ozone helps to reduce pollution problems in terms of COD, TOC, total dissolved solids and total suspended solids.

A survey of plants in Gujarat, India, for alkaloids, saponins, and tannins

Science.gov (United States)

Basalingappa L. Hungund; Chandravadan H. Pathak; Chandravadan H. Pathak

1971-01-01

A floristic and phytochemical survey of forests in Gujarat State, India, is being undertaken to identify sources of alkaloids, saponins, and tannins. This note is a report on the results of screening 105 plant species collected from that region.

EVALUATION OF LEATHER QUALITY AND ECOTOXICITY IN SIMULATED TANNERY WASTEWATERS USING MIMOSA TANNIN

Directory of Open Access Journals (Sweden)

ÇELİK Cem

2016-05-01

Full Text Available The leather tanning industry is characterized by the production of different kinds of effluents, generated in each step of leather processing. These effluents have various chemical compounds which may cause toxicity and endocrine disruption and are thus known as endocrine disrupting chemicals (EDC. Tanning stabilizes the protein structure of the hide and imparts heat stability, enhanced tensile properties, and resistance to microbial degradation. Currently most high quality leather is "chrome-tanned," produced by treatment of the hide with salts of the mineral chromium. In this study, the wastewater characteristics and ecotoxicity before and after tanning and retanning processes using mimosa tannin are assessed. Vegetable leather production procedure was followed using one dose mimosa tannin. Leather quality was evaluated according to standard methods. Wastewater characteristics showed that mimosa contributed high organic content to the wastewater. Although vegetable tannin was used the effluent toxicity was observed in tanning and retanning effluents. The preliminary results also showed that leather quality tests failed or at minimum level to comply with the standard values indicating that there is still a need to optimize the procedure including mimosa dose. This study was designed to produce eco-friendly leather using mimosa in tanning and retanning processes. Leather quality and the ecotoxicity of each process during leather production was assessed according to standard methods.

Polyethylene glycol and polyvinylpirrolidone effect on bacterial rRNA extraction and hybridization from cells exposed to tannins.

OpenAIRE

ARCURI, P.B.; THONNEY, M.L.; SCHOFIELD, P.; PELL, A.N.

2003-01-01

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/...

Tannin, protein contents and fatty acid compositions of the seeds of several Vicia L. species from Turkey

OpenAIRE

Kökten, Kağan; Koçak, Alpaslan; Bağci, Eyüp; Akçura, Mevlüt; Çelik, Sait

2010-01-01

The seedoils of six Vicia species (Leguminosae) were investigated for their protein, tannin contents and fatty acid compositions. The protein contents of the seeds were found to be between 21.87%-31.33%. The tannin contents of the seeds were found to be between 0.13%-1.07%. The fatty acid compositions of these six different species were determined by the GC of the methyl esters of their fatty acids. The oilseeds of Vicia species contain palmitic and stear...

Effects of a tannin-rich legume (Onobrychis viciifolia on in vitro ruminal biohydrogenation and fermentation

Directory of Open Access Journals (Sweden)

Gonzalo Hervás

2016-03-01

Full Text Available There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH of fatty acids (FA and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia, on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents. Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (-17, -23 and -11%, respectively. Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies.

Effects of a tannin-rich legume (Onobrychis viciifolia) on in vitro ruminal biohydrogenation and fermentation

Energy Technology Data Exchange (ETDEWEB)

González, M.A.; Peláez, F.R.; Martínez, A.L.; Avilés, C.; Peña, F.

2016-11-01

There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH) of fatty acids (FA) and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia), on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents). Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations) showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (‒17, ‒23 and ‒11%, respectively). Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies. (Author)

Kinetic and isotherm studies of Cu(II) biosorption onto valonia tannin resin

Energy Technology Data Exchange (ETDEWEB)

Sengil, I. Ayhan [Department of Environmental Engineering, Engineering Faculty, Sakarya University, 54100 Sakarya (Turkey)], E-mail: asengil@sakarya.edu.tr; Ozacar, Mahmut [Department of Chemistry, Science and Arts Faculty, Sakarya University, 54100 Sakarya (Turkey); Tuerkmenler, Harun [Institute of Sciences and Technology, Sakarya University, 54040 Sakarya (Turkey)

2009-03-15

The biosorption of Cu(II) from aqueous solutions by valonia tannin resin was investigated as a function of particle size, initial pH, contact time and initial metal ion concentration. The aim of this study was to understand the mechanisms that govern copper removal and find a suitable equilibrium isotherm and kinetic model for the copper removal in a batch reactor. The experimental isotherm data were analysed using the Langmuir, Freundlich and Temkin equations. The equilibrium data fit well in the Langmuir isotherm. The experimental data were analysed using four sorption kinetic models - the pseudo-first- and second-order equations, the Elovich and the intraparticle diffusion model equation - to determine the best fit equation for the biosorption of copper ions onto valonia tannin resin. Results show that the pseudo-second-order equation provides the best correlation for the biosorption process, whereas the Elovich equation also fits the experimental data well.

Biosynthesis of tannase and gallic acid from tannin rich substrates by Rhizopus oryzae and Aspergillus foetidus.

Science.gov (United States)

Mukherjee, Gargi; Banerjee, Rintu

2004-01-01

Modified solid-state fermentation (MSSF) of tannin-rich substrates for production of tannase and gallic acid was carried out using two fungal cultures, Rhizopus oryzae (RO IIT RB-13, NRRL 21498) and Aspergillus foetidus (GMRB013 MTCC 3557). The tannin rich substrates included powdered fruits of Terminalia chebula and Caesalpinia digyna pod cover powder. The different environmental parameters for the maximum production of tannase and gallic acid were optimized through media engineering. The highest yield of tannase and gallic acid was obtained after 60 h in case of Rhizopus oryzae and after 72 h by Aspergillus foetidus with 3 ml of induced inoculum. The optimum initial pH of the fermentation was found to be 4.5 in case of Rhizopus oryzae and 5.0 for Aspergillus foetidus. MSSF was carried out at the optimum conditions of 30 degrees C and 80% relative humidity. Collectively, the data reveal the potential of the modified solid-state fermentation process for the production of tannase and gallic acid from tannin-rich substrates with R. oryzae and A. foetidus.

Seasonal changes in nitrogen availability, and root and microbial uptake of ¹⁵N¹³C₉-phenylalanine and ¹⁵N-ammonium in situ at a temperate heath

DEFF Research Database (Denmark)

Andresen, Louise C.; Michelsen, Anders; Jonasson, Sven Evert

2011-01-01

In the plant biosynthesis of secondary compounds, phenylalanine is a precursor of condensed tannins. Tannins are deposited into the soil in plant root exudates and dead plant material and have been suggested to precipitate some soil nutrients and hence reduce nutrient availability for plants. Free...... amino acid,inorganic and microbial N concentration during the growing season was investigated in an ecosystem with a natural tannin chemosphere. The influence of tannins on the uptake of nitrogen in plants and microbes was followed by injecting tannic acid (TA), ammonium-15N and phenylalanine-15N/13C9...

Measurement of liquid-liquid equilibria for condensate + glycol and condensate + glycol + water systems

DEFF Research Database (Denmark)

Riaz, Muhammad; Kontogeorgis, Georgios; Stenby, Erling Halfdan

2011-01-01

,2-ethanediol (MEG) + condensate and MEG + water + condensate systems at temperatures from (275 to 323) K at atmospheric pressure. The condensate used in this work is a stabilized natural gas condensate from an offshore field in the North Sea. Compositional analysis of the natural gas condensate was carried out...... by gas chromatography, and detailed separation of individual condensate's components has been carried out. Approximately 85 peaks eluting before nonane were identified by their retention time. Peak areas were converted to mass fraction using 1-heptene as an internal standard. The components were divided...... into boiling range groups from hexane to nonane. Paraffinic (P), naphthenic (N), and aromatic (A) distributions were obtained for the boiling point fractions up to nonane. The average molar mass and the overall density of the condensate were measured experimentally. For the mutual solubility of MEG...

Eco-dyeing using Tamarindus indica L. seed coat tannin as a natural mordant for textiles with antibacterial activity

Directory of Open Access Journals (Sweden)

K.H. Prabhu

2014-12-01

Full Text Available Tamarind seed coat tannin was extracted and its tannin class was determined. The extracted tannin was employed as a natural mordant alone and in combination with metal mordant namely copper sulphate for cotton, wool and silk fabrics and dyed using natural dyes namely turmeric and pomegranate rind. The colour strength, colour coordinates, wash and light fastness were evaluated and compared for all the three fabrics with and without mordanting. The pre-mordanted fabrics on dyeing gave better colour strength, wash and light fastness than those dyeing obtained without mordanting. The total phenolic content of the extract was calculated and minimum inhibition concentration was 1% against both the Staphylococcus aureus and Escherichia coli bacteria. The mordanted and dyed fabrics resulted in good antibacterial activity up to 20 washes, when natural mordant was used along with 0.5% and 1% copper sulphate mordant and dyed with natural dyes.

Low pressure lithium condensation

International Nuclear Information System (INIS)

Wadkins, R.P.; Oh, C.H.

1985-01-01

A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

Changes of Microbial Population in the Rumen of Dairy Steers as Influenced by Plant Containing Tannins and Saponins and Roughage to Concentrate Ratio

Directory of Open Access Journals (Sweden)

N. Anantasook

2013-11-01

Full Text Available The objective of this study was to investigate microbial population in the rumen of dairy steers as influenced by supplementing with dietary condensed tannins and saponins and different roughage to concentrate ratios. Four, rumen fistulated dairy steers (Bos indicus were used in a 2×2 factorial arrangement in a 4×4 Latin square design. The main factors were two roughage to concentrate ratios (R:C, 60:40 and 40:60 and two supplementations of rain tree pod meal (RPM (0 and 60 g/kg of total DM intake. Chopped 30 g/kg urea treated rice straw was used as a roughage source. All animals received feed according to respective R:C ratios at 25 g/kg body weight. The RPM contained crude tannins and saponins at 84 and 143 g/kg of DM, respectively. It was found that ruminal pH decreased while ruminal temperature increased by a higher concentrate ratio (R:C 40:60 (p<0.05. In contrast, total bacterial, Ruminococus albus and viable proteolytic bacteria were not affected by dietary supplementation. Numbers of fungi, cellulolytic bacteria, Fibrobactor succinogenes and Ruminococus flavefaciens were higher while amylolytic bacteria was lower when steers were fed at 400 g/kg of concentrate. The population of Fibrobactor succinogenes, was found to be higher with RPM supplementation. In addition, the use of real-time PCR technique indicated that the population of protozoa and methanogens were decreased (p<0.05 with supplementation of RPM and with an increasing concentrate ratio. Supplementation of RPM and feeding different concentrate ratios resulted in changing the rumen microbes especially, when the animals were fed at 600 g/kg of concentrate and supplemented with RPM which significantly reduced the protozoa and methanogens population.

Evolution of Sangiovese Wines With Varied Tannin and Anthocyanin Ratios During Oxidative Aging