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Minjer Lu - One of the best experts on this subject based on the ideXlab platform.
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effect of Tannase treatment on protein tannin aggregation and sensory attributes of green tea infusion
Lwt - Food Science and Technology, 2009Co-Authors: Minjer Lu, Chinshuh ChenAbstract:Effect of Tannase enzymatic treatment on protein–tannin aggregation and sensory attributes of green tea infusion was investigated. Green tea leaves were extracted with hot water at 85 °C for 20 min, the tea infusion was then treated with Tannase. Results showed that both EGCG and ECG of the tea catechins were hydrolyzed by Tannase into EGC and EC, respectively, accompanied by production of gallic acid. The Tannase-treated tea infusion had a relatively lower binding ability with protein. Changes in the content of tea catechins, formation of tea cream, and turbidity of tea infusion with or without Tannase treatment were measured after 4 weeks. Content of catechins in the Tannase-modified tea remained almost unchanged, while those without Tannase treated (control) decreased significantly (p < 0.05). Meanwhile, better color appearance and less tea cream formation were observed for the Tannase-treated green tea, and tea cream formed for the control after storage. Results of the sensory evaluation showed that mouth feeling, taste and the overall acceptance of the Tannase-treated green tea infusion were all better than those of the control.
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enzymatic Tannase treatment of green tea increases in vitro inhibitory activity against n nitrosation of dimethylamine
Process Biochemistry, 2007Co-Authors: Minjer Lu, Chinshuh ChenAbstract:In vitro experiments were performed to test inhibition of nitrite-mediated N-nitrosation by individual catechins, green tea, and Tannase-treated green tea extracts. The extent of inhibition was measured via nitrosamine formation. Green tea with or without Tannase treatment was examined to study nitrosation inhibition in order to evaluate the inhibitory activities with the structural changes of catechins present in the extracts. The results showed that the Tannase-treated green tea had a greater ability to inhibit the nitrosation than green tea and ascorbic acid did. The Tannase-treated green tea strongly inhibited the formation of N-nitrosodimethylamine (NDMA). Among four major catechins tested, epigallocatechin blocked the N-nitrosation efficiently, and epigallocatechin gallate was more unstable than epigallocatechin at pH 2.0 or 8.0. These results suggest that the consumption of Tannase-treated green tea can reduce NDMA formation.
Gabriela Alves Macedo - One of the best experts on this subject based on the ideXlab platform.
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a new process for simultaneous production of Tannase and phytase by paecilomyces variotii in solid state fermentation of orange pomace
Bioprocess and Biosystems Engineering, 2012Co-Authors: Jose Valdo Madeira, Juliana Alves Macedo, Gabriela Alves MacedoAbstract:The production of enzymes such as Tannases and phytases by solid-state fermentation and their use in animal feed have become a subject of great interest. In the present work, Paecilomyces variotii was used to produce Tannase and phytase simultaneously. Solid-state fermentation, a process initially designed for Tannase production, was implemented here using orange pomace as substrate. Orange pomace is the waste product of the large orange juice industry in Brazil, and it has also been used as an ingredient in animal feed. In addition to enzymatic production, biotransformation of the phenolic content and antioxidant capacity of the orange pomace were analyzed after fermentation. Fermentation conditions, namely moisture level and tannic acid concentration rate, were studied using CCD methodology. The response surface obtained indicated that the highest Tannase activity was 5,000 U/gds after 96 h at 59% (v/w) and 3% (w/w) and that of phytase was 350 U/gds after 72 h at 66% (v/w) and 5.8% (w/w) of moisture level and tannic acid concentration, respectively. The amount of Tannase production was similar to the levels achieved in previous studies, but this was accomplished with a 7% (w/w) reduction in the amount of supplemental tannic acid required. These results are the first to show that P. variotii is capable of producing phytase at significant levels. Moreover, the antioxidant capacity of orange pomace when tested against the free radical ABTS was increased by approximately tenfold as a result of the fermentation process.
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Tannase production by paecilomyces variotii
Bioresource Technology, 2007Co-Authors: Vania Battestin, Gabriela Alves MacedoAbstract:: Surface response methodology was applied to the optimization of the laboratory scale production of Tannase using a lineage of Paecilomyces variotii. A preliminary study was conducted to evaluate the effects of variables, including temperature ( degrees C), residue (%) (coffee husk:wheat bran), tannic acid (%) and salt solutions (%) on the production of Tannase during 3, 5 and 7 days of fermentation. Among these variables, temperature, residues and tannic acid had significant effects on Tannase production. The variables were optimized using surface response methodology. The best conditions for Tannase production were: temperature (29-34 degrees C); tannic acid (8.5-14%); % residue (coffee husk:wheat bran 50:50) and incubation time of 5 days. The supplementation of external nitrogen and carbon sources at 0.4%, 0.8% and 1.2% concentration on Tannase production were studied in the optimized medium. Three different nitrogen sources included yeast extract, ammonia nitrate and sodium nitrate along with carbon source (starch) were studied. Only ammonia nitrate showed a significant effect on Tannase production. After the optimization process, the Tannase activity increased 8.6-fold.
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effects of temperature ph and additives on the activity of Tannase produced by paecilomyces variotii
Electronic Journal of Biotechnology, 2007Co-Authors: Vania Battestin, Gabriela Alves MacedoAbstract:A biochemical characterization of the Tannase from a Paecilomyces variotii strain isolated in Sao Paulo, Brazil was carried out. Paecilomyces variotii is a strain obtained from the screening of five hundred fungi that were tested for their production of Tannase. The enzyme produced was partially purified using ammonium sulfate precipitation followed by ion exchange chromatography, diethylaminoethyl (DEAE)-Sepharose. Effects of temperature and pH on the activity of crude Tannase crude and purified Tannase was studied. K m was found to be 0.61 µmol and V max = 0.55 U/mL. Temperature of 40 to 65oC and pH 4.5 to 6.5 were optimum for Tannase activity and stability; it could find potential use in the food-processing industry. The effects of different inhibitors, surfactants and chelators on the enzyme activity were also studied.
R K Saxena - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the versatility of Tannases produced from aspergillus niger and penicillium variable with respect to gallic acid production gallate ester synthesis animal feed improvement tannery effluent degradation and tannin stain removal
Research in Biotechnology, 2012Co-Authors: Shashi Sharma, R K SaxenaAbstract:The potentiality of Tannases produced from A. niger and P. variable were investigated with respect to gallic acid production, synthesis of gallate esters, animal feed improvement, tannery effluent degradation and tannin stain removal. Titrimetry results showed significant gallic acid production with 92 % conversion of 8 % tannic acid catalyzed by lyophilized A. niger Tannase and 60 % conversion of 3 % tannic acid by lyophilized P. variable Tannase in 8h. In gallate ester synthesis, esterfication rate was observed to be affected by the substrate molar ratio and temperature with maximum at 50◦C. Amongst the various organic solvents evaluated, n-hexane (log P 2.0) promoted maximum synthesis of both methyl gallate (MG) and propyl gallate (PG). Also low initial water activity (aw) of 0.11 – 0.33 obtained with LiCl2 and MgCl2.2H2O gave better yields for both MG and PG and by both Tannases. Furthermore, addition of molecular sieves at 0h in esterification reaction resulted in enhanced conversion of gallic acid and methanol into methyl gallate (90.7 % and 83 %) by A. niger and P. variable Tannase respectively. Similarly, 94.8 % and 89.6 % conversion of gallic acid and propanol into propyl gallate was achieved by A. niger and P. variable Tannase after addition of molecular sieves at 0h. In the hydrolysis of xylan and pectin, A. niger Tannase showed outstanding result by efficiently degrading them and producing ferulic acid at retention time of 75.90 min. Besides this, both A. niger and P. variable Tannases showed considerable degradation of 15 X diluted tannery effluent i.e. 45 and 36 % in 48 h respectively. In the removal of tea / tannin stains, the increase in temperature from 37◦C to 50◦C showed 15 % increase in reflectance for A. niger Tannase and 21 % for P. variabl e Tannase indicating its potential use in tannin stain remover (Tannosol).
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bacillus sphaericus the highest bacterial Tannase producer with potential for gallic acid synthesis
Journal of Bioscience and Bioengineering, 2011Co-Authors: Shailendra Raghuwanshi, Kakoli Dutt, Pritesh Gupta, Swati Misra, R K SaxenaAbstract:Abstract An indigenously isolated strain of Bacillus sphaericus was found to produce 1.21 IU/ml of Tannase under unoptimized conditions. Optimizing the process one variable at a time resulted in the production of 7.6 IU/ml of Tannase in 48 h in the presence of 1.5% tannic acid. A 9.26-fold increase in Tannase production was achieved upon further optimization using response surface methodology (RSM), a statistical approach. This increase led to a production level of 11.2 IU/ml in medium containing 2.0% tannic acid, 2.5% galactose, 0.25% ammonium chloride, and 0.1% MgSO 4 pH 6.0 incubated at 37°C and 100 rpm for 48 h with a 2.0% inoculum level. Scaling up Tannase production in a 30-l bioreactor resulted in the production of 16.54 IU/ml after 36 h. Thus far, this Tannase production is the highest reported in this bacterial strain. Partially purified Tannase exhibited an optimum pH of 5.0 with activity in the pH range of 3 to 8; 50°C was the optimal temperature for activity. Efficient conversion of tannic acid to purified gallic acid (90.80%) was achieved through crystallization.
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purification immobilization and characterization of Tannase from penicillium variable
Bioresource Technology, 2008Co-Authors: Shashi Sharma, Lata Agarwal, R K SaxenaAbstract:Abstract Tannase from Penicillium variable IARI 2031 was purified by a two-step purification strategy comprising of ultra-filtration using 100 kDa molecular weight cutoff and gel-filtration using Sephadex G-200. A purification fold of 135 with 91% yield of Tannase was obtained. The enzyme has temperature and pH optima of 50 °C and 5 °C, respectively. However, the functional temperature range is from 25 to 80 °C and functional pH range is from 3.0 to 8.0. This Tannase could successfully be immobilized on Amberlite IR where it retains about 85% of the initial catalytic activity even after ninth cycle of its use. Based on the Michaelis–Menten constant ( K m ) of Tannase, tannic acid is the best substrate with K m of 32 mM and V max of 1.11 μmol ml −1 min −1 . Tannase is inhibited by phenyl methyl sulphonyl fluoride (PMSF) and N -ethylmaleimide retaining only 28.1% and 19% residual activity indicating that this enzyme belongs to the class of serine hydrolases. Tannase in both crude and crude lyophilized forms is stable for one year retaining more than 60% residual activity.
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potential Tannase producers from the genera aspergillus and penicillium
Process Biochemistry, 2005Co-Authors: Anoop Batra, R K SaxenaAbstract:Abstract Tannase-producing ability of 35 Aspergilli and 25 Penicillii was examined both qualitatively on tannic acid agar plates and quantitatively in broth. Twenty-five Aspergilli and 20 Penicillii produced Tannase in culture broth. Potent Tannase-producing Aspergilli are Aspergillus fumigatus (8.3 IU/ml), Aspergillus versicolor (7.0 IU/ml), Aspergillus flavus (4.95 IU/ml) and Aspergillus caespitosum (4.47 IU/ml) and amongst Penicillii, Penicillium charlesii (4.82 IU/ml), Penicillium variable (4.70 IU/ml), Penicillium crustosum (4.7 IU/ml) and Penicillium restrictum (4.47 IU/ml). The crude Tannase from these fungi showed pH optima of 5.0, except in A. caespitosum , P. crustosum and P. variable , which had pH optima of 6.0. Optimum Tannase activity was at 60 °C in most of the potent producers, except in A. caespitosum , P. charlesii , P. crustosum and P. restrictum , which showed temperature optimum of 40 °C. Amongst the selected Aspergilli and Penicillii, Tannase from A. versicolor and P. restrictum was stable in a broad pH range of 3.0–8.0 for 24 h. The Tannase from A. versicolor is heat stable as it retained 67% activity at 70 °C after 1 h.
Luis Henrique Souza Guimaraes - One of the best experts on this subject based on the ideXlab platform.
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characterization of a multi tolerant tannin acyl hydrolase ii from aspergillus carbonarius produced under solid state fermentation
Electronic Journal of Biotechnology, 2015Co-Authors: Larissa Serrani Valera, Joao Atilio Jorge, Luis Henrique Souza GuimaraesAbstract:Background: Tannases are enzymes with biotechnological potential produced mainly by microorganisms as filamentous fungi. In this context, the production and characterization of a multi-tolerant Tannase from Aspergillus carbonarius is described. Results: The filamentous fungus A. carbonarius produced high levels of Tannase when cultivated under solid-state fermentation using green tea leaves as substrate/carbon source and tap water at a 1:1 ratio as the moisture agent for 72 h at 30°C. Two Tannase activity peaks were obtained during the purification step using DEAE-Cellulose. The second peak (peak II) was purified 11-fold with 14% recovery from a Sepharose CL-6B chromatographic column. The Tannase from peak II (Tannase II) was characterized as a heterodimeric glycoprotein of 134.89 kDa, estimated through gel filtration, with subunits of 65 kDa and 100 kDa, estimated through SDS-PAGE, and 48% carbohydrate content. The optimal temperature and pH for Tannase II activity was 60°C and 5.0, respectively. The enzyme was fully stable at temperatures ranging from 20-60°C for 120 min, and the half-life (T 1/2 ) at 75°C was 62 min. The activation energy was 28.93 KJ/mol. After incubation at pH 5.0 for 60 min, 75% of the enzyme activity was maintained. However, enzyme activity was increased in the presence of AgNO 3 and it was tolerant to solvents and detergents. Tannase II exhibited a better affinity for methyl gallate (Km = 1.42 mM) rather than for tannic acid (Km = 2.2 mM). Conclusion : A. carbonarius Tannase presented interesting properties as, for example, multi-tolerance, which highlight its potential for future application.
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optimization of culture conditions for Tannase production by aspergillus sp gm4 in solid state fermentation
Acta Scientiarum. Biological Sciences, 2015Co-Authors: Patrícia Nirlane Da Costa Souza, Luis Henrique Souza Guimaraes, Natália Da Costa Maia, Mario Lucio Vilela De Resende, Patrícia Gomes CardosoAbstract:The production of Tannase by Aspergillus sp. GM4 under solid-state fermentation (SSF) was investigated using different vegetables leaves such as mango, jamun, coffee and agricultural residues such as coffee husks, rice husks and wheat bran. Among substrates used jamun leaves yielded high Tannase production. The Plackett-Burman design was conducted to evaluate the effects of 12 independent variables on the production of Tannase under SSF using jamun leaves as substrate. Among these variables, incubation time, potassium nitrate and tannic acid had significant effects on enzyme production. The best incubation time was studied and others variables were optimized using the Central Composite Design. The best conditions for Tannase production were: incubation time of 2 days; tannic acid 1.53% (w/w) and potassium nitrate 2.71% (w/w). After the optimization process, the Tannase production increased 4.65-fold. Keywords : surface response methodology; enzyme; jamun
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optimization of culture conditions for Tannase production by aspergillus sp gm4 in solid state fermentation
Acta Scientiarum. Health Science, 2015Co-Authors: Patrícia Nirlane Da Costa Souza, Luis Henrique Souza Guimaraes, Natália Da Costa Maia, Mario Lucio Vilela De Resende, Patrícia Gomes CardosoAbstract:Tannase is an industrially important enzyme produ ced by a large number of microorganisms. This study analyzed the production of Tannase by Aspergillus s...
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The Optimization of Aspergillus sp. GM4 Tannase Production under Submerged Fermentation
Ai Magazine, 2014Co-Authors: Alessandra Gonçalves De Melo, Luis Henrique Souza Guimaraes, Mario Lucio Vilela De Resende, Rayssa Cristina Faria Pedroso, José Guilherme Lembi Ferreira Alves, Eustáquio Souza Dias, Patrícia Gomes CardosoAbstract:Tannase is a hydrolytic enzyme that is involved in the biodegradation of tannins and it has biotechnological potential in the pharmaceutical, chemical, food and beverage industries. Microorganisms, especially filamentous fungi, are important Tannase producers. The aims of this work were to find a potential Tannase producer and to improve the cultivation conditions. Three Aspergillus species (A. japonicus 246A, A. tamarii 3 and Aspergillus sp. GM4) were investigated in different culture media (Adams, Czapeck, Khanna, M5 and Vogel) and inducers (1% and 2% tannic acid; 1% green tea; 1% methyl gallate; 1% gallic acid). Aspergillus sp. GM4 and Adams medium were selected. The Tannase production by Aspergillus sp. GM4 in Adams medium was induced in the presence of 2% (w/v) tannic acid and gallic acid as carbon sources, while green tea was not able to induce Tannase production. The Plackett-Burman screening design was performed with the variables MgSO4, KH2PO4, yeast extract, tannic acid, agitation rate and salt solution. The variables MgSO4 and agitation rate were selected for the optimization of Tannase production using a Central Composite Rotatable Design. Under optimized conditions, a 2.66-fold increase in the enzyme production was observed with small modifications in the medium composition.
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characterization of a glucose and solvent tolerant extracellular Tannase from aspergillus phoenicis
Journal of Molecular Catalysis B-enzymatic, 2013Co-Authors: Alana Jacomini Riul, Heloisa Bressan Goncalves, Joao Atilio Jorge, Luis Henrique Souza GuimaraesAbstract:Abstract Tannases have attracted wider attention because of their biotechnological potential, especially enzymes from filamentous fungi and other microorganisms. However, the biodiversity of these microorganisms has been poorly explored, and few strains were identified for Tannase production and characterization. This article describes the production, purification and characterization of a glucose- and solvent-tolerant extracellular Tannase from Aspergillus phoenicis. High enzymatic levels were obtained in Khanna medium containing tannic acid up to 72 h at 30 °C under 100 rpm. The purified enzyme with 65% of carbohydrate content had an apparent native molecular mass of 218 kDa with subunits of 120 kDa and 93 kDa and was stable at 50 °C for 1 h. Optima of temperature and pH were 60 °C and 5.0–6.5, respectively. The enzyme was not affected significantly by most ions, detergents and organic solvents. While glucose did not affect the Tannase activity, the addition of a high concentration of gallic acid did. The Km values were 1.7 mM (tannic acid), 14.3 mM (methyl-gallate) and 0.6 mM (propyl-gallate). The enzyme was able to catalyze the transesterification reaction to produce propyl-gallate. All biochemical properties suggest the biotechnological potential of the glucose- and solvent-tolerant Tannase from A. phoenicis.
Chinshuh Chen - One of the best experts on this subject based on the ideXlab platform.
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effect of Tannase treatment on protein tannin aggregation and sensory attributes of green tea infusion
Lwt - Food Science and Technology, 2009Co-Authors: Minjer Lu, Chinshuh ChenAbstract:Effect of Tannase enzymatic treatment on protein–tannin aggregation and sensory attributes of green tea infusion was investigated. Green tea leaves were extracted with hot water at 85 °C for 20 min, the tea infusion was then treated with Tannase. Results showed that both EGCG and ECG of the tea catechins were hydrolyzed by Tannase into EGC and EC, respectively, accompanied by production of gallic acid. The Tannase-treated tea infusion had a relatively lower binding ability with protein. Changes in the content of tea catechins, formation of tea cream, and turbidity of tea infusion with or without Tannase treatment were measured after 4 weeks. Content of catechins in the Tannase-modified tea remained almost unchanged, while those without Tannase treated (control) decreased significantly (p < 0.05). Meanwhile, better color appearance and less tea cream formation were observed for the Tannase-treated green tea, and tea cream formed for the control after storage. Results of the sensory evaluation showed that mouth feeling, taste and the overall acceptance of the Tannase-treated green tea infusion were all better than those of the control.
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enzymatic Tannase treatment of green tea increases in vitro inhibitory activity against n nitrosation of dimethylamine
Process Biochemistry, 2007Co-Authors: Minjer Lu, Chinshuh ChenAbstract:In vitro experiments were performed to test inhibition of nitrite-mediated N-nitrosation by individual catechins, green tea, and Tannase-treated green tea extracts. The extent of inhibition was measured via nitrosamine formation. Green tea with or without Tannase treatment was examined to study nitrosation inhibition in order to evaluate the inhibitory activities with the structural changes of catechins present in the extracts. The results showed that the Tannase-treated green tea had a greater ability to inhibit the nitrosation than green tea and ascorbic acid did. The Tannase-treated green tea strongly inhibited the formation of N-nitrosodimethylamine (NDMA). Among four major catechins tested, epigallocatechin blocked the N-nitrosation efficiently, and epigallocatechin gallate was more unstable than epigallocatechin at pH 2.0 or 8.0. These results suggest that the consumption of Tannase-treated green tea can reduce NDMA formation.
