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Search Results: 1 - 10 of 186 matches for " tannin "
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Tannin–Phenol Formaldehyde Resins As Binders for Cellulosic Fibers: Mechanical Properties  [PDF]
A.S. Hussein, K.I. Ibrahim, K. M. Abdulla
Natural Resources (NR) , 2011, DOI: 10.4236/nr.2011.22013
Abstract: In this study Eucalyptus tannin (T) was isolated from outer bark of Eucalyptus trees; as sodium phenoxide salt and used as extender or copolymer into phenol formaldehyde (PF) resin at five percent (10, 20, 30, 40 and 50)% W/W. Tan-nin-phenol formaldehyde (TPF) and tannin formaldehyde-phenol formaldehyde (TFPF) resins that synthesized in this study were evaluated as adhesive material for cellulosic fibers by study the mechanical properties of the composite sheets .The results show that the substituting of (PF) with tannin at (10 –50)% W/W give resins with mechanical properties comparable or near to those of pure (PF) , where the tensile strength at break (Tb) ranging from 15.15 Mpa to 22.27 Mpa as compared with 17.6 Mpa for pure (PF); while the impact strength properties (Im) of composites sheets increased with increased the (T) percents which were about 5.16 KJ/m2 for (TPF – 10%) and 7.21 KJ/m2 for (TPF - 50%) .On the other hand modification of (T) to tannin formaldehyde resin (TF) appear less performance at the results of this study , this effect probably to low penetration of (TFPF) resins between the small voids of cellulose fibers when soaked it in resin solutions. In general the results of this study indicate that the Eucalyptus tannin can be used for par-tial substitution of (PF) to produce resins with feasible mechanical properties and can be used in some applications of (PF) resins.
Comparison of Phytochemicals and Anti-Nutritional Factors in Some Selected Wild and Edible Bean in Nigeria  [PDF]
Awoyinka O. A., Ileola A. O., Imeoria C. N., Tijani T. D., Oladele F. C., Asaolu M. F.
Food and Nutrition Sciences (FNS) , 2016, DOI: 10.4236/fns.2016.72012
Abstract: This work aims at analyzing the bioactive and anti-nutritional compounds of edible and wild beans when unprocessed and malted. Qualitative screening of phytochemicals in the various bean samples was determined in ethanol and petroleum ether solvents. Results of the anti-nutritional compositions of unprocessed wild bean extracted with petroleum ether showed there were no traces of saponin and polyphenol, in Feregede and also in edible bean-IT07K-243-1-10 which also had no traces of saponin and tannin. After malting, saponin was totally absent in Pakala, Mucuna, IT97k-499-35, IT07k-243-1-10, and IT04k-333-2 respectively. Polyphenol was also found to be absent in IT07k-243-1-10. Mucuna has the highest phytic acid level (7.8867 ± 0.011) while Feregede has the lowest phytic acid level (2.9810 ± 0.004). Otili has the highest anti-trypsin level (12.001 ± 0.0013). This study showed varying levels of anti-nutrients on the respective bean samples when unprocessed but decreased marginally after malting. It was keenly noted that values derived, either before and after malting were not significantly different (P ≤ 0.05) from each other. In all, this study had further shown that malting process enhanced removal of anti-nutrients which invariably would lead to availability of nutrient for animal and human consumption.
Antiproliferative Activity, Antioxidant Capacity and Tannin Content in Plants of Semi-Arid Northeastern Brazil ?
Joabe Gomes de Melo,Thiago Ant?nio De Sousa Araújo,Valérium Thijan Nobre de Almeida e Castro,Daniela Lyra de Vasconcelos Cabral,Maria Do Desterro Rodrigues,Silene Carneiro do Nascimento,Elba Lúcia Cavalcanti de Amorim,Ulysses Paulino De Albuquerque
Molecules , 2010, DOI: 10.3390/molecules15128534
Abstract: The objective of this study was to evaluate antiproliferative activity, antioxidant capacity and tannin content in plants from semi-arid northeastern Brazil (Caatinga). For this study, we selected 14 species and we assayed the methanol extracts for antiproliferative activity against the HEp-2 (laryngeal cancer) and NCI-H292 (lung cancer) cell lines using the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazole) (MTT) method. In addition, the antioxidant activity was evaluated with the DPPH (2,2-diphenyl-2-picrylhydrazyl) assay, and the tannin content was determined by the radial diffusion method. Plants with better antioxidant activity (expressed in a dose able to decrease the initial DPPH concentration by 50%, or IC50) and with higher levels of tannins were: Poincianella pyramidalis (42.95 ± 1.77 μg/mL IC50 and 8.17 ± 0.64 tannin content), Jatropha mollissima (54.09 ± 4.36μg/mL IC50 and 2.35 ± 0.08 tannin content) and Anadenanthera colubrina (73.24 ± 1.47 μg/mL IC50 and 4.41 ± 0.47 tannin content). Plants with enhanced antiproliferative activity (% living cells) were Annona muricata (24.94 ± 0.74 in NCI-H292), Lantana camara (25.8 ± 0.19 in NCI-H292), Handroanthus impetiginosus (41.8 ± 0.47 in NCI-H292) and Mentzelia aspera (45.61 ± 1.94 in HEp-2). For species with better antioxidant and antiproliferative activities, we suggest future in vitro and in vivo comparative studies with other pharmacological models, and to start a process of purification and identification of the possible molecule(s) responsible for the observed pharmacological activity. We believe that the flora of Brazilian semi-arid areas can be a valuable source of plants rich in tannins, cytotoxic compounds and antioxidant agents.
Silagem de sorgo de porte baixo com diferentes teores de tanino e de umidade no colmo.I - pH e teores de matéria seca e de ácidos graxos durante a fermenta??o
Rodriguez, N.M.;Gon?alves, L.C.;Nogueira, F.A.S.;Borges, A.L.C.C.;Zago, C.P.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 1999, DOI: 10.1590/S0102-09351999000500015
Abstract: four hybrid forage sorghums with different tannin concentrations and moisture in the stem were ensiled in laboratory silos made of "pvc" tubes. the silos were opened after 1 (p2), 7 (p3), 14 (p4), 28 (p5) e 56 (p6) days after ensiling, in order to evaluate fermentation patterns and other silage characteristics. twenty-four treatments were used, with four repetitions each: four hybrids (t1=moist stem/low tannin, t2=not moist stem/low tannin, t3=not moist stem/high tannin, t4= moist stem/high tannin) and with six periods, since the forages before ensiling (p1) were also studied. dry matter content (dm), dry matter losses, ph, lactic acid and volatile fat acids were determined. data were evaluated by analysis of variance, with mean separation achieved using tukey statistical test. the stability was achieved between p4 and p5. t1 and t2 had lower dm content and acetate than t3 and t4. all silages showed good fermentation patterns.
Obten??o de extratos de guaraná ricos em cafeína por processo enzimático e adsor??o de taninos
Ribeiro, Bernardo Dias;Coelho, Maria Alice Zarur;Barreto, Daniel Weingart;
Brazilian Journal of Food Technology , 2012, DOI: 10.1590/S1981-67232012005000020
Abstract: guarana-flavoured beverages are very popular in brazil and have shown an excellent sales potential on foreign markets. according to brazilian law, each 100 ml of guarana-flavoured beverages must contain between 0.02 g and 0.2 g of guarana seed or its equivalent. these levels are normally obtained by adding a concentrated hydroalcoholic extract or sugar syrup containing guarana extract, directly to the beverage. however, the use of more concentrated extracts is limited by the presence of tannins, which imparts astringency and a dark colour to the final product. in this work the development of an enzymatic process to obtain non-alcoholic guarana extracts with low tannin concentrations and high caffeine contents was studied using an experimental design and adsorption processes. by way of a fractional factorial design the quantities of 0.25% (v/v) pectinase and 0.1% (v/v) glucoamylase were determined, which were maintained in the central composite design, obtaining as the optimal conditions: 0.23% (v/v) cellulase, 0.86% (v/v) hemicellulase, 1% (v/v) alpha-amylase, 5.5 h extraction time, 200 rpm and 50 °c, producing a caffeine/tannin ratio of 1.65. using a magnesium oxide adsorption process at 10% (w/v), a caffeine/tannin ratio of 7.3 was obtained.
Sele??o de fungos produtores de tanase em resíduos vegetais ricos em taninos
Macedo, Gabriela Alves;Matsuda, Luis Katsumi;Battestin, Vania;
Ciência e Agrotecnologia , 2005, DOI: 10.1590/S1413-70542005000400016
Abstract: tannin acyl hydrolase (e.c: 3.1.1.20) or tannase is an enzyme which hydrolyses ester and depside bonds of hydrolysable tannins releasing gallic acid and glucose. tannase is an extracellular, inducible enzyme, produced by fungi, bacteria and yeast. the tannase is produced by solid-state, liquid surface and submerged fermentation. the solid-state fermentation offers a number of advantages over submerged and liquid conventional fermentation for the enzimes production. the production is simple, using vegetable residues such as coffee wastes, grape, cashew or by-products as wheat bran, rice or oats, to which tannic acid is added. the use of residues is an alternative to solve pollution problems that can be caused by an incorrect environmental disposal. tannase enzyme has several applications on food, juices and pharmaceutical industries. the objective of this work was to select tannase producing fungi and to study the production of this enzyme in vegetable residues rich in tannin. the first stage of the selection was carried in solid-state fermentation using as substrate wheat bran supplemented with 0.5% of tannic acid. among the 400 tested lineages, 6.75% of the fungi produced the enzyme. the lineages that showed the best activities were lab345g, lab53g and lab153g, with 0.3862, 0.2149 and 0.1848 u activities values, respectively these lineages were tested in vegetables residues as coffee and grape, adding 0.5 and 1.5% of tannic acid in the fermentation environment. the best result was obtained using la153g and coffee residues, with an activity of 0.275u being observed.
A REVIEW ON SARACA INDICA PLANT
Bhadauria Preeti,Arora Bharti,Alok nath Sharma,Singh Vishwabhan
International Research Journal of Pharmacy , 2012,
Abstract: Saraca indica is an important indigenous plant with lots of traditional importance belonging to the family caesalpinaceae. These are the wonderful herb that claims to cure several diseases according to ayurvedic medicine. It mainly contains glycosides, tannin, saponin, flavonoids, and sterol. It posseses various activities such as analgesic, antipyretic, fungitoxic, anthelmintic, antidiabetic, larvicidal activity, antimicrobial activity, CNS depressant activity, Antiulcer activity, anti-inflammatory activity etc. This review contains pharmacognostic study of various parts of plant, phytochemical constituents and pharmacological activities of various parts of plant.
Effect of Polyethylene Glycol (PEG) on Blood Parameters of Sheep Given Leucaena Pallida Leaves Base Diet
Rusdi
Journal of Animal Production , 2007,
Abstract: Penelitian ini dilakukan untuk mengevaluasi kemampuan PEG dalam mengurangi pengaruh negatif dari pemberian daun Leucaena pallida pada ternak domba melalui pengamatan parameter darah. Sebanyak 12 ekor domba ditempatkan secara acak pada dua perlakuan dengan 6 ulangan. Domba diberi pakan dasar daun Leucaena pallida dengan tambahan PEG atau tanpa PEG selama empat minggu melalui automatic feeders. Data parameter darah antar perlakuan dianalisa dengan uji t. Hasil penelitian menunjukkan bahwa PEG secara konsisten meningkatkan kecernaan makanan terkonsumsi dalam saluran pencernaan domba yang ditunjukan dengan meningkatnya konsentrasi urea darah, glukosa darah dan b-hydroxybutyrat darah. Dengan demikian dapat dikatakan bahwa penambahan PEG ke dalam ransum yang mengandung tannin berpotensi untuk meningkatkan nilai hayati pakan. (Animal Production 9(1): 18-22 (2007) Kata Kunci : PEG, darah, tannin
Digestibility of Nutrients on Broiler Given Various Protein Sources and Two Levels of Quebracho Tannin
Rusdi
Journal of Animal Production , 2006,
Abstract: Suatu penelitian telah dilaksanakan yang bertujuan untuk melihat pengaruh sumber protein dan kandungan tannin dalam ransum terhadap kecernaan nutrien pada ayam broiler. Sebanyak enampuluh empat ayam telah digunakan dan ditempatkan secara acak dalam faktorial 2x4 sebanyak delapan ulangan. Protein yang digunakan meliputi gelatin, tepung ikan, tepung bulu dan campuran tepung daging dan kedelai. Hasil penelitian menunjukkan bahwa Quebracho Tanin (QT) menekan kecernaan nutrien pada broiler. Sumber protein mempunyai kemampuan untuk mengoreksi pengaruh negatif tanin dimana tepung ikan menghasilkan nilai tertinggi dan tepung bulu menghasilkan nilai yang paling rendah pada kecernaan. Nilai kecernaan protein masing-masing untuk tepung ikan dan tepung bulu sebesar 54,40 dan 44,30%. (Animal Production 8(1): 50-58 (2006) Kata Kunci : Kecernaan, quebracho, tannin
TANNIN CONTENT DETERMINATION IN THE BARK OF Eucalyptus spp
Paulo Fernando Trugilho,Fábio Akira Mori,José Tarcísio Lima,Dione Pereira Cardoso
CERNE , 2003,
Abstract: 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.
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