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Effect of Acacia molissima tannin extract on the control of gastrointestinal parasites in sheep

MINHO, Alessandro Pelegrine; BUENO, Ives Cláudio da Silva; LOUVANDINI, Helder; JACKSON, F; GENNARI, Solange Maria; ABDALLA, Adibe Luiz
Fonte: Amsterdam Publicador: Amsterdam
Tipo: Artigo de Revista Científica
ENG
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46.27%
This study investigates the anthelmintic effect of condensed tannin extracts (CTE) from Acacia molissima on lambs naturally infected with Haemonchus contortus and Trichostrongylus colubriformis. Twenty Santa Inês sheep were divided into four groups and allocated to four paddocks with five animals each in a 60-day trial. Two groups were drenched with CTE (1.6 g/kg LW) for two consecutive days at the beginning of the trial and 30 days later and two groups were maintained undrenched (control) throughout the trial. The animals were weighed every 14 days; blood was collected once a week and faecal egg counts (FEC) were measured twice a week. Twenty-eight days after the final CTE administration, all lambs were slaughtered and worm burden counts were determined. Mean body weight changes were not different among treatments. Globular volume for the drenched group was higher or showed tendency to be higher than the undrenched group at days 14 (P=0.043), 21 (P=0.074), 28 (P=0.026), 42 (P=0.007) and 48 (P=0.089). No differences were observed in haemoglobin values between treatments. The CTE drenching was associated with a reduction in FEC (P=0.003) and worm burden in the abomasum (P<0.003), but not in the small intestine. The results confirm the anthelmintic effects of CTE on gastrointestinal nematodes in lambs and demonstrate the potential use of CTE as an alternative endoparasite control in livestock

A new approach for in vitro bioassay to measure tannin biological effects based on a gas production technique

BUENO, Ives C. S.; VITTI, Dorinha M. S. S.; LOUVANDINI, Helder; ABDALLA, Adibe L.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.51%
The aim of this paper was to study a method based on gas production technique to measure the biological effects of tannins on rumen fermentation. Six feeds were used as fermentation substrates in a semi-automated gas method: feed A - aroeira (Astronium urundeuva); feed B - jurema preta (Mimosa hostilis), feed C - sorghum grains (Sorghum bicolor); feed D - Tifton-85 (Cynodon sp.); and two others prepared mixing 450 g sorghum leaves, 450 g concentrate (maize and soybean meal) and 100 g either of acacia (Acacia mearnsii) tannin extract (feed E) or quebracho (Schinopsis lorentzii) tannin extract (feed F) per kg (w:w). Three assays were carried out to standardize the bioassay for tannins. The first assay compared two binding agents (polyethylene glycol - PEG - and polyvinyl polypirrolidone - PVPP) to attenuate the tannin effects. The complex formed by PEG and tannins showed to be more stable than PVPP and tannins. Then, in the second assay, PEG was used as binding agent, and this assay was done to evaluate levels of PEG (0, 500, 750, 1000 and 1250 mg/g DM) to minimize the tannin effect. All the tested levels of PEG produced a response to evaluate tannin effects but the best response was for dose of 1000 mg/g DM. Using this dose of PEG, the final assay was carried out to test three compounds (tannic acid...

Tannin-phenolic resins: Synthesis, characterization, and application as matrix in biobased composites reinforced with sisal fibers

Ramires, Elaine C.; Frollini, Elisabete
Fonte: ELSEVIER SCI LTD; OXFORD Publicador: ELSEVIER SCI LTD; OXFORD
Tipo: Artigo de Revista Científica
ENG
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36.48%
A tannin-phenolic resin (40 wt% of tannin, characterized by H-1 nuclear magnetic resonance (NMR) and C-13 NMR, Fourier transform infrared, thermogravimetry, differential scanning calorimetry) was used to prepare composites reinforced with sisal fibers (30-70 wt%). Inverse gas chromatography results showed that the sisal fibers and the tannin-phenolic thermoset have close values of the dispersive component and also have predominance of acid sites (acid character) at the surface, confirming the favoring of interaction between the sisal fibers and the tannin-phenolic matrix at the interface. The Izod impact strength increased up to 50 wt% of sisal fibers. This composite also showed high storage modulus, and the lower loss modulus, confirming its good fiber/matrix interface, also observed by SEM images. A composite with good properties was prepared from high content of raw material obtained from renewable sources (40 wt% of tannin substituted the phenol in the preparation of the matrix and 50 wt% of matrix was replaced by sisal fibers). (C) 2012 Elsevier Ltd. All rights reserved.; FAPESP (The State of Sao Paulo Research Foundation, Brazil); FAPESP (The State of Sao Paulo Research Foundation, Brazil); CNPq (National Research Council, Brazil); CNPq (National Research Council...

Porcentagens de saponinas e taninos em vinte e oito cultivares de alfafa (Medicago sativa L.) em duas épocas de corte - Botucatu - SP

Vieira, Maria Eunice de Queiroz; Costa, Ciniro; Silveira, Antônio Carlos; Arrigoni, Mário de Beni
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: 1432-1438
POR
Relevância na Pesquisa
36.56%
O objetivo do estudo foi determinar os conteúdos de saponinas, taninos e a solubilidade da proteína (SP) de 28 cultivares de alfafa: Crioula, Monarca, BR 4, Alto Great, MH 4, SW 9210 A, 5929, BR 1, EL Grande, 5715, MH 15, Valley Plus, BR 2, Rio, SW 8210, Maricopa, ICI 990, 5888, P 30, Alfa-200, WL 516, SW 8112 A, BR 3, Florida 77, Araucana, Falcon, Semit 921 e Sutter. O material analisado foi obtido do 10º e 14º corte, respectivamente; em 08/12/97 e 16/04/98, de um experimento desenvolvido na Faculdade de Medicina Veterinária e Zootecnia, UNESP, Botucatu. Amostras de cada cultivar foram colhidas, pesadas e secas em estufa a 52ºC. As saponinas foram extraídas com solvente hidrofílico e lipofílico e o conteúdo foi calculado pela equação y=0,8121x-1,4759, R² = 1,00. A extração dos taninos totais e condensados foi efetuada por meio de ultra-som (12 min), sendo os taninos totais determinados pela equação: y=44,978 + 0,5644 com R²=0,9977 e os condensados, multiplicando-se a absorbância por 78,26 dividido pelo teor de matéria seca. A SP foi determinada pelo método de KOH, de acordo com a seguinte fórmula: SP (%) = proteína solúvel x 100/proteína bruta da amostra. Os teores de saponinas, taninos totais e condensados e a solubilidade da proteína não diferiram (P>0...

Tropical tanniniferous legumes used as an option to mitigate sheep enteric methane emission

Moreira, Guilherme Dias; Tavares Lima, Paulo de Mello; Borges, Barbara Oliveira; Primavesi, Odo; Longo, Cibele; McManus, Concepta; Abdalla, Adibe; Louvandini, Helder
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 879-882
ENG
Relevância na Pesquisa
46.27%
This study presents the first results from Brazil using SF6 tracer technique adapted from cattle to evaluate the capability of condensed tannin (CT) present in three tropical legume forages, Leucaena leucocephala (LEU), Styzolobium aterrimum (STA), and Mimosa caesalpiniaefolia Benth (MIM) to reduce enteric CH4 production in Santa Ins sheep. Twelve male lambs [27.88 +/- 2.85 kg body weight (BW)] were allocated in individual metabolic cages for 20-day adaptation followed by 6 days for measuring dry matter intake (DMI) and CH4 emission. All lambs received water, mineral supplement, and Cynodon dactylon v. coast-cross hay ad libitum. The treatments consisted of soybean meal (710 g/kg) and ground corn (290 g/kg) [control (CON)]; soybean meal (150 g/kg), ground corn (30 g/kg), and Leucaena hay (820 g/kg) (LEU); soybean meal (160 g/kg), ground corn (150 g/kg), and Mucuna hay (690 g/kg) (STA); and soybean meal (280 g/kg), ground corn (190 g/kg), and Mimosa hay (530 g/kg) (MIM); all calculated to provide 40 g/kg CT (except for CON). DMI (in grams of DMI per kilogram BW per day) was lower for LEU (22.0) than CON (29.3), STA (31.2), and MIM (31.6). The LEU group showed emission of 7.8 g CH4/day, significantly lower than CON (10.5 g CH4/day), STA (10.4 g CH4/day)...

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome

Lamy, E; da Costa, G; Santos, R; Capela e Silva, F; Potes, J; Pereira, A; Coelho, AV; Sales Baptista, E
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
66.65%
Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep Ovis aries)and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two dimensional gel electrophoresis. Matrix assisted Laser desorption ionization – time of flight(MALDI-TOF)and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.

Changes in mice whole saliva soluble proteome induced by tannin-enriched diets.

Lamy, E; Graça, G; da Costa, G; Franco, C; Capela e Silva, F; Baptista, E; Coelho, AV
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.55%
Background Previous studies suggested that dietary tannin ingestion may induce changes in mouse salivary proteins in addition to the primarily studied proline-rich proteins (PRPs). The aim of the present study was to determine the protein expression changes induced by condensed tannin intake on the fraction of mouse whole salivary proteins that are unable to form insoluble tannin-protein complexes. Two-dimensional polyacrylamide gel electrophoresis protein separation was used, followed by protein identification by mass spectrometry. Results Fifty-seven protein spots were excised from control group gels, and 21 different proteins were identified. With tannin consumption, the expression levels of one α-amylase isoform and one unidentified protein increased, whereas acidic mammalian chitinase and Muc10 decreased. Additionally, two basic spots that stained pink with Coomassie Brilliant Blue R-250 were newly observed, suggesting that some induced PRPs may remain uncomplexed or form soluble complexes with tannins. Conclusion This proteomic analysis provides evidence that other salivary proteins, in addition to tannin-precipitating proteins, are affected by tannin ingestion. Changes in the expression levels of the acidic mammalian chitinase precursor and in one of the 14 salivary α-amylase isoforms underscores the need to further investigate their role in tannin ingestion.

Morphological alterations in salivary glands of mice (Mus musculus) submitted to tannin enriched diets: comparison with sialotrophic effects of sympathetic agonists stimulation

Lamy,E.; Baptista,E.S.; Coelho,A.V.; Silva,F. Capela e
Fonte: Universidade Federal de Minas Gerais, Escola de Veterinária Publicador: Universidade Federal de Minas Gerais, Escola de Veterinária
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 EN
Relevância na Pesquisa
46.44%
In order to study the effects of tannins at histomorphological level, mice were either fed with three structurally different types of tannins (tannic acid, chestnut, and quebracho) or treated with isoproterenol, during 10 days. Acini of parotid and submandibular glands increased significantly, being the increase higher for parotid compared to submandibular glands, and higher in the quebracho compared with the other tannin groups. Sublingual acinar size also increased after tannin consumption, by opposition to isoproterenol-treated animals. The results present evidences that the effects produced by tannins are dependent on their structure.

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

McSweeney, Christopher S.; Palmer, Brian; Bunch, Rowan; Krause, Denis O.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /07/1999 EN
Relevância na Pesquisa
36.62%
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...

Effect of alkali treatment on physiological activity of cotton condensed tannin.

Rousselle, M A; Elissalde, M H; Domelsmith, L N
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1990 EN
Relevância na Pesquisa
46.62%
Cotton dusts contain condensed tannins and endotoxins, which are suspected of contributing to the development of acute and chronic biological responses in some cotton textile mill workers. Condensed tannin extracted from cotton dust was coated on to cellulose powder, and the tannin coated powder was treated with an alkali solvent system previously developed to reduce the endotoxin content and pulmonary toxicity of cotton dust. Physiological activities of the dusts and powders were compared by assaying the production of the arachidonic acid metabolites prostaglandin F2 alpha (PGF2 alpha), thromboxane A2 (TxA2) (the precursor to thromboxane B2 (TxB2], leukotriene C4 (LTC4), and prostaglandin E2 (PGE2) by guinea pig pulmonary cells obtained by lung lavage. Cotton dust stimulated the pulmonary cells to produce a total of 29 pg metabolites per 10(6) cells. Production of metabolites by cells stimulated with tannin coated cellulose powder was reduced to 8.3 pg/10(6) cells. Alkali treatment of the tannin coated cellulose powder resulted in a further decrease in its ability to stimulate the cells, producing 3.5 pg metabolites per 10(6) cells. The ability of the dusts and powders to stimulate production of metabolites of arachidonic acid by pulmonary cells from guinea pigs was highly correlated with tannin content of the materials...

Identification of histatins as tannin-binding proteins in human saliva.

Yan, Q; Bennick, A
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/10/1995 EN
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36.78%
Tannins have a number of detrimental biological effects and these include interference with normal growth and metabolism if they are present in the feed of various animals. Proline-rich proteins (PRPs) in saliva have been shown to provide protection against tannin, but little is known about the mechanism of protection and interaction of other salivary proteins with tannin. To identify tannin-binding human salivary proteins, parotid and submandibular/sublingual saliva samples were adsorbed with tannin. PRPs, and in particular a group of low-M(r) proteins, were readily precipitated by tannin. The low-M(r) proteins were purified from parotid saliva and demonstrated to be histatins, a family of well-characterized histidine-rich salivary proteins. The ability of synthetic histatin 5, as well as an acidic PRP (PRP-1) and gelatin to precipitate quebracho condensed tannin and tannic acid was determined. At pH 7.4 histatin 5 was the most effective precipitant of both condensed tannin and tannic acid and it also precipitated the largest amount of condensed tannin at pH 3.0, but the smallest amount of tannic acid at that pH. In contrast PRP-1 showed a greater ability to precipitate both condensed tannin and tannic acid at pH 3.0 than at pH 7.4. Under most circumstances histatin 5 was therefore more effective in precipitating tannins than proteins with high proline content which generally have been recognized as strong precipitants of tannin. Pre-incubation of tannic acid with alpha-amylase inhibited the enzyme...

Toxicity to endothelial cells mediated by cotton bract tannin. Potential contribution to the pathogenesis of byssinosis.

Johnson, C. M.; Hanson, M. N.; Rohrbach, M. S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1986 EN
Relevância na Pesquisa
36.57%
Byssinosis is an occupational disease of textile workers caused by exposure to the bract portion of the cotton plant in the form of mill dust. The authors established an in vitro cytotoxicity assay using 51Cr release to assess time- and dose-dependent toxicity of condensed tannin, a component of bracts, on porcine aortic and pulmonary arterial endothelial cells. Tannin produced dose-dependent toxicity to both types of endothelial cells; aortic endothelial cells were more sensitive than were endothelial cells from the pulmonary artery. Skin fibroblasts were relatively insensitive to tannin. Cytotoxicity was not immediate. Release of 51Cr was preceded by a several-hour period during which the endothelial cells underwent profound morphologic changes (as assessed by light and electron microscopy). Even brief exposure of endothelial cells to tannin produced later toxicity and morphologic changes. Condensed tannin causes time- and dose-dependent injury to endothelial cells in vitro at doses potentially achievable in vivo.

Gastrointestinal Bacterial and Methanogenic Archaea Diversity Dynamics Associated with Condensed Tannin-Containing Pine Bark Diet in Goats Using 16S rDNA Amplicon Pyrosequencing

Min, Byeng R.; Solaiman, Sandra; Shange, Raymon; Eun, Jong-Su
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
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46.32%
Eighteen Kiko-cross meat goats (n = 6) were used to collect gastrointestinal (GI) bacteria and methanogenic archaea for diversity measures when fed condensed tannin-containing pine bark (PB). Three dietary treatments were tested: control diet (0% PB and 30% wheat straw (WS); 0.17% condensed tannins (CT) dry matter (DM)); 15% PB and 15% WS (1.6% CT DM), and 30% PB and 0% WS (3.2% CT DM). A 16S rDNA bacterial tag-encoded FLX amplicon pyrosequencing technique was used to characterize and elucidate changes in GI bacteria and methanogenic archaea diversity among the diets. Proteobacteria was the most dominant phylum in goats with mean relative abundance values ranging from 39.7 (30% PB) to 46.5% (control) and 47.1% (15% PB). Other phyla individually accounted for fewer than 25% of the relative abundance observed. Predominant methanogens were Methanobrevibacter (75, 72, and 49%), Methanosphaera (3.3, 2.3, and 3.4%), and Methanobacteriaceae (1.2, 0.6, and 0.7%) population in control, 15, and 30% PB, respectively. Among methanogens, Methanobrevibacter was linearly decreased (P = 0.05) with increasing PB supplementation. These results indicate that feeding PB selectively altered bacteria and methanogenic archaeal populations in the GI tract of goats.

Composition of condensed tannins from Calliandra calothyrsus and correlation with in sacco digestibility

Rakhmani, S.; Brooker, J.; Jones, G.; Palmer, B.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
46.5%
Calliandra calothyrsus accessions differ widely in digestibility for livestock. It is not clear, however, whether this is related to differences in condensed tannin levels or to other factors. Condensed tannins (CT) were extracted from seven different accessions of C. calothyrsus, and were examined for protein binding, pH stability of protein tannin complexes and CT composition. The compositional data was correlated with dry matter and nitrogen digestibility in sacco. Calliandra CT formed insoluble complexes with casein, bovine serum albumin and rubisco protein in an approximate ratio of 1:2 (w/w, tannin:protein) and the insoluble complexes were relatively stable to pH within the range of pH from 2.5 to 8.0. Polymeric proanthocyanidins were associated with both insoluble and soluble protein fractions, but the flavonols and flavonol glycosides were only associated with the soluble fraction. Total CT from each accession was fractionated by SepPak C18 reverse phase column chromatography into phenolic acids, monomers, oligomers/flavonols and polymeric proanthocyanidin fractions and quantified as total phenolics. There was wide variation between fractions across the seven accessions. Fractionation data were correlated with dry matter and nitrogen digestibility in sacco for each accession. Correlations were strongly negative (−0.799) and strongly positive (+0.800) for oligomers/flavonols and polymeric proanthocyanidins...

Condensed Tannin Accumulation and Composition in Skin of Shiraz and Cabernet Sauvignon Grapes during Berry Development

Hanlin, Rachel L.; Downey, Mark Oliver
Fonte: Amer Soc Enology Viticulture Publicador: Amer Soc Enology Viticulture
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
56.75%
Condensed tannins derived from the grape berry play a significant role in wine astringency, bitterness, color stability, and aging potential. Understanding the regional, varietal, and seasonal variability in winegrape tannin composition throughout berry development is essential for developing vineyard strategies to manage and manipulate winegrape tannin to meet winery specifications. Current knowledge of tannin accumulation and composition in grape berries is largely based on a single variety and geographical region, with most studies investigating seed tannin. To explore the variation in tannin accumulation and composition, Shiraz and Cabernet Sauvignon grape skin from two growing seasons in the Sunraysia region of southeast Australia were measured by acid-catalyzed cleavage in the presence of phloroglucinol. High-performance liquid chromatography was used to quantify the subunit composition, total tannin content, and average polymer length throughout berry development. The pattern of tannin accumulation and composition were similar for both varieties and seasons, with tannin content highest at fruit set before declining toward veraison. The pattern of accumulation and composition seen in grape skin from this study was different to that previously reported in Shiraz from the cooler growing region of McLaren Vale in South Australia where tannin content was highest at veraison. Results indicate that the differences between the pattern of tannin accumulation and composition in Sunraysia and McLaren Vale may be due to regional influences...

Review: Condensed tannin and grape cell wall interactions and their impact on tannin extractability into wine

Hanlin, R.; Hrmova, M.; Harbertson, J.; Downey, M.
Fonte: Australian Society of Viticulture and Oenology Publicador: Australian Society of Viticulture and Oenology
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
46.71%
It has been suggested that tannin extraction from grape berries into wine is limited by tannin binding to cell walls. Here we review the current state of knowledge and identify gaps in research that would enable characterisation of these interactions. Such characterisation could improve tannin extraction management in winemaking. The work identified in this review supports the hypothesis that tannin–cell wall interactions are formed by hydrogen bonding and hydrophobic interactions with the binding capacity of the cell walls influenced by tannin and polysaccharide structure and composition. Cell wall changes during berry development may increase the tannin-binding capacity of cell walls, while tannin structure may also influence its affinity for cell wall material. This review also identifies the need to investigate cultural and environmental factors that affect tannin and polysaccharide composition, to characterise the tannin-binding capacity of cell walls and to develop methods for assessing tannin-binding capacity of fruit prior to harvest. It is envisaged that a detailed understanding of tannin interactions with other components in the grape would lead to a predictive model for extractability of condensed tannins into wine.; R.L. Hanlin...

Isolation and characterisation of tannin-resistant bacteria from the rumen of feral goats and camels.

Tjakradidjaja, Anita Sardiana
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
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36.75%
Low availability and poor nutrient quality of tropical grasses result in low levels of animal production. Browse/shrub legumes such as mulga (Acacia sp.) and calliandra (Calliandra calothyrsus) can be used as supplements to improve animal production. However, their utilisation is limited by the presence of antinutritional compounds, such as tannins. Tannins are polyphenolic compounds that are capable of binding other nutrients to form stable complexes. Tannins comprise hydrolysable (HT) and condensed tannins (CT) with CTs being the major form found in the legumes. Their concentration in feeds determines their effect on animal production. Low levels of tannin (< 40 g.kg DM⁻¹) protect feed protein from degradation by rumen microbes, thereby increasing the amount of protein passing through the rumen, and reducing the potential for bloat. However, high concentrations of tannin retard animal production through the inhibition of enzyme activities of some rumen bacteria, decreasing the availability of protein and fibre, and reducing feed intake. Tannins in high concentrations also bind nutrients such as protein and carbohydrates; tannin-protein or tannin-carbohydrate complexes are difficult to digest by rumen microbes or by enzymes secreted by ruminants in the gastrointestinal tract. This decreases the availability of protein and carbohydrate for the animals...

Condensed tannin and cell wall composition in wine grapes: influence on tannin extraction from grapes into wine.

Hanlin, Rachel L.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
Relevância na Pesquisa
46.76%
Condensed tannins derived from the grape berry contribute to the organoleptic properties of wine, in particular, astringency, as well as wine colour and aging stability. The contribution of different grape tannin structures to wine quality is not well understood. In particular, the measurement of tannin in grapes is not indicative of the amount and type of tannin extracted into wine, which makes it difficult to predict the impact on wine quality. Tannin extraction is thought to be influenced by interactions between tannins and cell walls of the grape berry. This study aimed to investigate the influence of grape tannin and cell wall composition on extraction of tannin into wine. Tannin distribution in terms of the distribution of polymer length or degree of polymerisation (DP), the concentration and subunit composition was determined in grape skin, seed and wine of Shiraz and Cabernet Sauvignon wine grapes. The polysaccharide composition and tannin binding capacity of cell walls and the amount of tannin extracted into wine at different grape maturity levels were also investigated. The extent of variation in Shiraz skin tannin distribution and cell wall structure and its tannin binding capacity was also investigated across a range of environmental conditions...

In vitro effect of condensed tannin extract from acacia (Acacia mearnsii) on gastrointestinal nematodes of sheep; Efeito in vitro do extrato de tanino condensado de acácia (Acacia mearnsii) em nematóides gastrintestinais de ovinos

MINHO, Alessandro Pelegrine; BUENO, Ives Cláudio da Silva; GENNARI, Solange Maria; JACKSON, Frank; ABDALLA, Adibe Luiz
Fonte: Colégio Brasileiro de Parasitologia Veterinária; São Paulo Publicador: Colégio Brasileiro de Parasitologia Veterinária; São Paulo
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.48%
O objetivo deste trabalho foi determinar os efeitos inibitórios do extrato condensado de tanino da acácia sobre a fase de alimentação do primeiro estádio (L1) da forma larvar de Haemonchus contortus, Trichostrongylus vitrinus e Teladorsagia circumcincta. O experimento foi desenvolvido com para avaliar o efeito inibitório sobre o processo de alimentação de cada uma das espécies de nematóides. A L1 recuperada de amostras fecais do doador com infecção monoespecífica foi incubada em diferentes diluições de extrato de acácia (AE). A 'DL IND. 50' foi determinada para as três espécies de nematóides. Polietileno glicol (PEG) foi adicionado a todas as diluições de AE para inativar os taninos condensados (CT) da acácia e para confirmar os efeitos sobre as L1. O impacto de CT na inibição alimentar da larva (LH) for detectado sobre todas as espécies de nematóides utilizados (H. contortus, T. colubriformis e T. circumcincta). Houve diferenças entre o controle aquoso e os grupos tratados com CT (P < 0,01). Os valores da 'DL IND. 50' foram de 0,043; 0,038 e 0,050 (EP = 0,0024) para H. contortus, T. vitrinus e T. circumcincta respectivamente. Diferença foi detectada entre os tratamentos AE e AE + PEG (P < 0,01). A análise dos resultados sugere que o efeito direto de CT sobre a L1 dos nematóides estudados pode ser usado como controle alternativo de nematóides de ovinos; The aim of this study was to determine the inhibitory effects of condensed tannin extract from acacia on the feeding of first-stage larvae (L1) of Haemonchus contortus...

Condensed tannin content of several shrub species from a mountain area in northern Spain, and its relationship to various indicators of nutritive value

Frutos, Pilar; Hervás, Gonzalo; Ramos, Graciano; Giráldez, Francisco Javier; Mantecón, Ángel R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 129716 bytes; application/pdf
ENG
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http://dx.doi.org/10.1016/S0377-8401(01)00323-6; The condensed tannin (CT) content of eight shrub species (Cytisus purgans, Cytisus scoparius, Genista florida, Genista occidentalis, Calluna vulgaris, Erica arborea, Erica australis and Juniperus communis) from a grazing mountain area of northern Spain was analysed and related to various indicators of nutritive value. Chemical composition, in vitro gas production, OM degradation and true DM digestibility were evaluated in samples collected in January and June. With the exception of two samples comprised of considerable amounts of flowers, the shrub legumes examined had low contents of CT (less than 6.51 g quebracho tannin equivalents/kg DM) which would generally be considered unlikely to affect digestion of nutrients in the gastrointestinal tract of animals. However, Ericaceae species and J. communis, which are evergreen species, showed a high CT content (higher than 176 g quebracho tannin equivalents/kg DM) throughout the year. CT were negatively correlated (P<0.05) with OM degradation and cumulative gas production, and positively correlated with lag time, which is consistent with the extensively reported suppressive effect of condensed tannins on rumen degradation and on the interference of these compounds with microbial attachment to feeds. The positive correlation between these plant secondary compounds and the partitioning factor (OM degradation/total gas production) indicates that the effect of CT is more strongly reflected in the reduction of gas production than in the reduction of OM degradation.; This work was supported by the Junta de Castilla y León (Projects CSI 3/99).; Peer reviewed