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1.
Caesalpinia digyna, a tannin-rich forest residue, was used as substrate for production of tannase and gallic acid. Media engineering was carried out under solid-state fermentation, submerged fermentation and modified solid state fermentation conditions for optimum synthesis of tannase and gallic acid (based on 58% tannin content in the raw material). Tannase vis-à-vis gallic acid recovery under modified solid-state fermentation condition was maximum. Conversions of tannin to gallic acid under solid-state fermentation, submerged fermentation and modified solid-state fermentation conditions were 30.5%, 27.5% and 90.9%, respectively. Journal of Industrial Microbiology & Biotechnology (2000) 25, 29–38. Received 02 November 1999/ Accepted in revised form 12 February 2000  相似文献   

2.
Spores from the co-culture of Aspergillus foetidus and Rhizopus oryzae were subjected to UV, heat and NTG (3-nitro,5-methylguanidine) mutagenesis. A few colonies were screened from the selected media for tannase study. Amongst all, the best mutant isolated from the heat treatment (60 degrees C for 60 min) was SCPR 337. The maximum yield of gallic acid and tannase in case of mutant strain was 95.2% and 53.6 U/ml with an incubation period of 30 h as compared to wild strain where the incubation period was 48 h with an enzyme activity of 44.2 U/ml and gallic acid yield of 94%, respectively. The mutant was sensitive to tetracycline and was also an over-producer of protease and amylase.  相似文献   

3.
《Process Biochemistry》2014,49(2):271-276
This work studied the effect of a sequential addition of substrate on tannase reaction for the increase of epigallocatechin (EGC) and gallic acid. The addition of 0.5–1% GTE increased the production of gallic acid during 2 h in a single tannase reaction, while the addition of more than 2% in GTE rather showed a decrease in gallic acid level with an increase of EGCG level compared with 1% GTE addition group, suggesting that GTE addition of 2% and over inhibits the reaction of tannase. Examination of sequential addition of 1% GTE on tannase reaction showed that second addition of 1% GTE at 2 h promoted tannase reaction by increasing production of gallic acid, but further addition (2 and 3 h) rather inhibited tannase reaction with lowered gallic acid and enhanced EGCG levels. This result showed that one additional treatment of 1% GTE during tannase reaction is effective in an increase of gallic acid production. Moreover, levels of degallated products including EGC, EC, and GC were increased by 7.3, 4.5, and 3.5-fold, respectively in sequential addition of GTE at 2 h. pH change derived from gallic acid production was not shown to related to tannase activity. Therefore, our study suggests that one sequential addition is a suitable process for desirable production of green tea extracts enriched in active components such as gallic acid and EGC.  相似文献   

4.
Abstract

A novel tannase and gallic acid-producing Penicillium rolfsii (CCMB 714) was isolated from cocoa leaves from the South of Bahia. The influence of nutritional sources and the simultaneous effect of parameters involved in the fermentation process were available. Tannase (9.97 U?mL?1) and gallic acid (9?mg mL?1) production were obtained in 48?h by submerged fermentation in non-optimized conditions. Among the carbon sources, tested gallic acid and tannic acid showed the highest tannase production (p<.05) when compared with methyl gallate and glucose. After optimization using the temperature and tannic acid concentration as variables with the Central Compound Rotational Design (CCRD), the maximal tannase production (25.6?U mL?1) was obtained at 29.8?°C and 12.7%, respectively, which represents an increase of 2.56 times in relation to the initial activity. The parameters optimized for the maximum production of gallic acid (21.51?mg mL?1) were 30?°C and 10% tannic acid. P. rolfsii CCMB 714 is a new strain with a high tannase and gallic acid production and the gallic acid produced is very important, mainly for its applications in the food and pharmaceutical industry.  相似文献   

5.
Optimization of tannase production by Aureobasidium pullulans DBS66   总被引:1,自引:0,他引:1  
Tannase production by Aureobasidium pullulans DBS66 was optimized. The organism produced maximum tannase in the presence of 1% tannic acid after 36 h. Maximum gallic acid accumulation was observed within 36 h and tannic acid in the fermented broth was completely degraded after 42 h of growth. Glucose had a stimulatory effect on tannase synthesis at 0.1% (w/v) concentration. The organism showed maximum tannase production with (NH4)2HPO4 as nitrogen source. Shaking speed of 120 rpm and 50-ml broth volume have been found to be suitable for maximum tannase production.  相似文献   

6.
《Fungal biology》2022,126(8):471-479
The enzyme tannase is of great industrial and biotechnological importance for the hydrolysis of vegetable tannins, reducing their undesirable effects and generating products for a wide range of processes. Thus, the search for new microorganisms that permit more stable tannase production is of considerable importance. A strain of P. mangiferae isolated from cocoa leaves was selected and investigated for its capacity to produce tannase enzymes and gallic acid through submerged fermentation. The assessment of the variables affecting tannase production by P. mangiferae showed that tannic acid, ammonium nitrate and temperature were the most significant (8.4 U/mL). The variables were analyzed using Response Surface Methodology - RSM (Box-Behnken design), with the best conditions for tannase production being: 1.9% carbon source, 1% nitrogen source and temperature of 23 °C. Tannase activity doubled (16.9 U/mL) after the optimization process when compared to the initial fermentation. A pH of 7.0 was optimal for the tannase and it presented stability above 80% with pH between 4.0 and 7.0 after 2h of incubation. The optimal temperature was 30 °C and activity remained at above 80% at 40–60 °C after 1 h. Production of gallic acid was achieved with 1% tannic acid (0.9 mg/mL) and P. mangiferae had not used up the gallic acid produced by tannic acid hydrolysis after 144 h of fermentation. A 5% tannic acid concentration was the best for gallic acid production (1.6 mg/mL). These results demonstrate P. mangiferae’s potential for tannase and gallic acid production for biotechnological applications.  相似文献   

7.
Enzymatic gallic acid esterification   总被引:5,自引:0,他引:5  
Gallic acid esters of n-propyl and amyl alcohols have been produced by enzymatic synthesis in organic solvents using immobilized tannase. Studies indicate that maximum esterification of gallic acid occurs with amyl alcohol. The enzyme shows broad alcohol specificity. However, the enzyme exhibits absolute specificity for the acid portion of the ester. Studies were carried out on K(m), V(max), pH, and temperature optima.  相似文献   

8.
Summary Tannase was produced by modified solid-state fermentation (MSSF) of tannin rich substrates by a co-culture of the two filamentous fungi, Rhizopus oryzae and Aspergillus foetidus. The enzyme thus produced was then partially purified by solvent precipitation and DEAE-Sephadex column chromatography. A study on the effects of temperature and pH was made on the activity of tannase so purified. The optimum values of incubation time, reaction temperature and pH for tannase activity were 5 min, 40 °C and 5.0 respectively. The half-life period thermal stability and kinetic constants (K m 0.21 mM, V max 4.9×10−2 M min-1 at 40 °C) of this tannase were determined and the effects of different metal ions, surfactants, chelators, denaturants and inhibitors on the enzyme activity were also studied.  相似文献   

9.
The tannase production by Paecilomyces variotii was confirmed by high performance thin layer chromatography (HPTLC), and substrate specificity of the tannase was determined by zymogram analysis in sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS–PAGE). A clear band of activity observed after electrophoresis of culture filtrate in non-denaturing gels indicated the production of extracellular tannase by P. varoitii. HPTLC analysis revealed that gallic acid was the enzymatic degradation product of tannic acid during the fermentation process. The optimum condition for tannase production was at 72 h of incubation in shaking condition and addition of 1.5% tannic acid, 1% glucose and 0.2% sodium nitrate at temperature of 35°C and pH of 5–7. The production of extracellular tannase from Paecilomyces variotii was investigated under optimized conditions in solid-state fermentation (SSF), submerged fermentation (SmF) and liquid surface fermentation (LSF) processes. The maximum extracellular tannase production was obtained within 60 h of incubation under SSF followed by SmF and LSF.  相似文献   

10.
Tannins, present in various foods, feeds and forages, have anti-nutritional activity; however, presence of tannase in microorganisms inhabiting rumen and gastrointestinal tract of animals results in detoxification of these tannins. The present investigation was carried out to study the degradation profile of tannins by Enterococcus faecalis and to purify tannase. E. faecalis was observed to degrade tannic acid (1.0% in minimal media) to gallic acid, pyrogallol and resorcinol. Tannase from E. faecalis was purified up to 18.7 folds, with a recovery of 41.7%, using ammonium sulphate precipitation, followed by DEAE-cellulose and Sephadex G-150. The 45 kDa protein had an optimum activity at 40 °C and pH 6.0 at substrate concentration of 0.25 mM methyl gallate.  相似文献   

11.
Naturally immobilized tannase (tannin acyl hydrolase, E.C. 3.1.1.20) has many advantages, as it avoids the expensive and laborious operation of isolation, purification, and immobilization, plus it is highly stable in adverse pH and temperature. However, in the case of cell-associated enzymes, since the enzyme is associated with the biomass, separation of the pure biomass is necessary. However, tannic acid, a known inducer of tannase, forms insoluble complexes with media proteins, making it difficult to separate pure biomass. Therefore, this study optimizes the production of cell-associated tannase using a "protein-tannin complex" free media. An exploratory study was first conducted in shake-flasks to select the inducer, carbon source, and nitrogen sources. As a result it was found that gallic acid induces tannase synthesis, a tryptose broth gives higher biomass, and lactose supplementation is beneficial. The medium was then optimized using response surface methodology based on the full factorial central composite design in a 3 l bioreactor. A 2(3) factorial design augmented by 7 axial points (alpha = 1.682) and 2 replicates at the center point was implemented in 17 experiments. A mathematical model was also developed to show the effect of each medium component and their interactions on the production of cell-associated tannase. The validity of the proposed model was verified, and the optimized medium was shown to produce maximum cell-associated tannase activity of 9.65 U/l, which is 93.8% higher than the activity in the basal medium, after 12 h at pH 5.0, 30 degrees C. The optimum medium consists of 38 g/l lactose, 50 g/l tryptose, and 2.8 g/l gallic acid.  相似文献   

12.
The potential of gallotannin, methyl gallate, gallic acid, and pyrogallol to induce tannin acyl hydrolase (EC 3.1.1.20) activity in Aspergillus niger, Aspergillus fischerii, Fusarium solani, and Trichoderma viride has been investigated. The maximum induction ratios recorded were A. fischerii (26.7), F. solani (26.1), and T. viride (40.7) when the fungi were induced with gallotannin, gallic acid, and methyl gallate, respectively. A. niger was devoid of basal enzyme activity. The gallotannin tolerance limits for A. niger, A. fischerii, F. solani, and T. viride were determined by progressively increasing the gallotannin concentration and were found to be 20, 4, 3, and 3%, respectively. F. solanii induced with 3% gallotannin has been recommended for the production of tannase enzyme.  相似文献   

13.
A novel fungal strain, Aspergillus ficuum Gim 3.6, was evaluated for its tannase-producing capability in a wheat bran-based solid-state fermentation. Thin-layer chromatography (TLC) analysis revealed that the strain was able to degrade tannic acid to gallic acid and pyrogallol during the fermentation process. Quantitation of enzyme activity demonstrated that this strain was capable of producing a relatively high yield of extracellular tannase. Single-factor optimization of process parameters resulted in high yield of tannase after 60 hr of incubation at a pH of 5.0 at 30°C, 1 mL of inoculum size, and 1:1 solid–liquid ratio in the presence of 2.0% (w/v) tannic acid as inducer. The potential of aqueous two-phase extraction (ATPE) for the purification of tannase was investigated. Influence of various parameters such as phase-forming salt, molecular weight of polyethylene glycol (PEG), pH, and stability ratio on tannase partition and purification was studied. In all the systems, the target enzyme was observed to preferentially partition to the PEG-rich top phase, and the best result of purification (2.74-fold) with an enzyme activity recovery of 77.17% was obtained in the system containing 17% (w/w) sodium citrate and 18.18% (w/w) PEG1000, at pH 7.0.  相似文献   

14.
An extracellular tannase (tannin acyl hydrolase) was isolated from Paecilomyces variotii and purified from cell-free culture filtrate using ammonium sulfate precipitation followed by ion exchange and gel filtration chromatography. Fractional precipitation of the culture filtrate with ammonium sulfate yielded 78.7% with 13.6-folds purification, and diethylaminoethyl–cellulose column chromatography and gel filtration showed 19.4-folds and 30.5-folds purifications, respectively. Molecular mass of tannase was found 149.8 kDa through native polyacrylamide gel electrophoresis (PAGE) analysis. Sodium dodecyl sulphate–PAGE revealed that the purified tannase was a monomeric enzyme with a molecular mass of 45 kDa. Temperature of 30 to 50°C and pH of 5.0 to 7.0 were optimum for tannase activity and stability. Tannase immobilized on alginate beads could hydrolyze tannic acid even after extensive reuse and retained about 85% of the initial activity. Thin layer chromatography, high performance liquid chromatography, and 1H-nuclear magnetic resonance spectral analysis confirmed that gallic acid was formed as a byproduct during hydrolysis of tannic acid.  相似文献   

15.
Aspergillus niger with mycelium-bound tannase activity was employed to investigate the synthesis of propyl gallate from gallic acid and 1-propanol in organic solvents. The effects of various organic solvents (log P: −1.0 to 6.6) on the enzymatic reactions showed that benzene (log P: 2.0) was the most suitable solvent. The water content and protonation state of mycelium-bound enzyme both had significant effects on the activity of tannase. The maximum molar conversion (65%) was achieved with 7.3% (v/v) 1-propanol and 5.56 mM gallic acid at stirring speeds of 200 rev/min, 40 °C in presence of anhydrous sodium sulfate and PEG-10,000. Enzyme specificity for the alcohol portion (C1–C8) of the ester showed that the optimum synthesis was observed with alcohols ranging from C3 to C5.  相似文献   

16.
Visual Reading Method for Detection of Bacterial Tannase   总被引:7,自引:1,他引:6       下载免费PDF全文
Tannase activity of bacteria capable of degrading tannin-protein complexes was determined by a newly developed visual reading method. The method is based on two phenomena: (i) the ability of tannase to hydrolyze methyl gallate to release free gallic acid and (ii) the green to brown coloration of gallic acid after prolonged exposure to oxygen in an alkaline condition. The method has been successfully used to detect the presence of tannase in the cultures of bacteria capable of degrading tannin-protein complexes.  相似文献   

17.
Tannase an industrially important enzyme was produced by Aspergillus aculeatus DBF9 through a solid-state fermentation (SSF). The organism produced good amount of enzyme and gallic acid in wheat bran among the solid substrate used in SSF. Maximum enzyme and gallic acid production occurred in 5% tannic acid after 72 h. Eighty percent initial substrate moisture and 30 degrees C temperature was found suitable for tannase production.  相似文献   

18.
利用黑曲霉单宁酶酶法制取没食子酸的研究   总被引:5,自引:0,他引:5  
利用已有的 10株高单宁酶活性的菌株为起始菌 ,经活化分离选择 ,借助Ⅱ级发酵培养程序、生物转化、结合TLC分析进行筛选实验。最后选出具有高单宁酶活性的 1号和 5 0号菌株 ,开展了没食子酸 (GA)克量级生物转化法制备实验 ,结果表明 ,本酶法工艺是可行的 ,在发酵液中GA的浓度分别达到2 0 .6mg/ml和 2 1 3mg/ml,产品产率 (以从五倍子提取的单宁酸计 )达到 41 2 %和 42 6 % ,具有潜在的工业开发价值  相似文献   

19.
青霉单宁酶高活性菌株的诱变选育   总被引:1,自引:0,他引:1  
利用塔拉单宁诱导丝状真菌产生单宁酶的原理,通过富集培养,从天然源分离得到30株具有较高单宁酶活性的青霉菌;经二级发酵程序,对这30株菌进行了生物转化复筛实验,选择出能水解塔拉单宁,且生物催化活性较高的青霉野生株Penicilliumsp.No.23,对No.23进行经紫外诱变处理,诱变株经筛选,最后得到1株具有稳定遗传性的单宁酶高活性菌株,其单宁酶活性比出发菌株提高了35%。  相似文献   

20.
A spectrophotometric method for assay of tannase using rhodanine   总被引:9,自引:0,他引:9  
A method for assay of microbial tannase (tannin acyl hydrolase) based on the formation of chromogen between gallic acid and rhodanine is reported. Unlike the previous protocols, this method is sensitive up to gallic acid concentration of 5 nmol and has a precision of 1.7% (relative standard deviation). The assay is complete in a short time, very convenient, and reproducible.  相似文献   

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