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1.
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   

2.
Tannins may reduce rumen degradability of protein, increase the proportion of feed protein reaching the lower digestive tract for enzymatic digestion and thereby increase the efficiency of protein utilization. The objective was to assess the effects of different types and levels of tannins on rumen in vitro gas production and its kinetics, in vitro true degradability (IVTD) and rumen degradability of protein (IVRDP), and microbial protein synthesis by incubating alfalfa (Medicago sativa L.) hay in buffered rumen fluid. Alfalfa was incubated in buffered rumen fluid with and without the addition of different levels of gallic acid (GA), quebracho tannin (QT), or tannic acid (TA). Tannins at the lower inclusion levels had minimal effects on fermentation products compared to the higher levels. Addition of QT and TA reduced ammonium-N (NH4+-N) concentration. Addition of QT at 20, 40, and 60 g/kg DM decreased NH4+-N by 2, 7, and 12% compared with control whereas addition of TA reduced NH4+-N by 5, 6, and 12% when added at 20, 40 and 60 g/kg DM, respectively. In experiment 2, addition of QT at 50, 100, and 150 g/kg DM, resulted in reduction of NH4+-N by 12, 30, and 51%, respectively, compared with the control. Addition of TA at 50, 100, and 150 g/kd DM reduced NH4+-N by 14, 26, and 47% compared with control. Inclusion of QT at 50, 100, 150 DM reduced IVRDP by 13, 30, and 36% compared with control whereas at these levels of inclusion, TA resulted in reduction of IVRDP by 14, 25, and 48%. Rate of gas production decreased (P<0.001), while asymptotic gas production increased (P<0.0001) with increasing level of GA and TA. Quebracho tannin decreased (P<0.0001) both the rate and asymptotic of gas production. Gallic acid had a positive effect on fermentation as indicated by increased gas production and total short chain fatty acids (SCFA) production. Quebracho tannin decreased 24 h gas production, IVTD, and total SCFA production. Acetate to propionate ratio increased with the addition of GA and but decreased when QT was added. Addition of tannins did not markedly increase total purines but numerical values tended to be higher in the presence of tannins compared with the control. Efficiency of microbial growth was lower in the presence of GA and unaltered by TA, but higher in the presence of QT compared with the control. The effect of tannins on rumen fermentation and protein degradation varied with type and level of tannins. In vivo studies will be conducted to validate the in vitro results.  相似文献   

3.
《Process Biochemistry》2014,49(4):541-546
Potent antioxidant phenolics are derived from tannin biodegradation. Understanding of biodegradation pathways through the identification of the intermediates molecules of great value like tannins is important to pursuit the production of bioactive monomers. Biodegradation of tannins remains poorly understood due to their chemical complexity and reactivity. Tannic acid biodegradation by Aspergillus niger GH1 in submerged fermentation (SF) and solid state fermentation (SSF) was evaluated by liquid chromatography coupled to mass spectrometry (LC–MS). Both cultures were kinetically monitored for the biodegradation profiles during 72 h. Differences in tannic acid composition were evidenced and the consumption of substrate and identification of biodegradation intermediates were achieved. The mechanism of tannic acid degradation by A. niger GH1 is by degradation of high molecular weight gallotannins and highly polymerized tannins to small molecules like gallic acid, digalloyl glucose and trigalloyl glucose. Important differences on time of substrate uptake and product release were revealed.  相似文献   

4.

Aims

To examine tannic acid (TA) utilization capacity by nitrogen‐fixing bacteria, Azotobacter sp. SSB81, and identify the intermediate products during biotransformation. Another aim of this work is to investigate the effects of TA on major biopolymers like extracellular polysaccharide (EPS) and polyhydroxybutyrate (PHB) synthesis.

Methods and Results

Tannic acid utilization and tolerance capacity of the strain was determined according to CLSI method. Intermediate products were identified using high‐performance liquid chromatography, LC‐MS/MS and 1H NMR analysis. Intermediates were quantified by multiple reactions monitoring using LC‐MS/MS. The strain was able to tolerate a high level of TA and utilized through enzymatic system. Growth of Azotobacter in TA‐supplemented medium was characterized by an extended lag phase and decreased growth rate. Presence of TA catalytic enzymes as tannase, polyphenol oxidase (PPO) and phenol decarboxylase was confirmed in cell lysate using their specific substrates. PPO activity was more prominent in TA‐supplemented mineral medium after 48 h of growth when gallic to ellagic acid (EA) reversible reaction was remarkable. Phase contrast and scanning electron microscopic analysis revealed elongated and irregular size of Azotobacter cells in response to TA. 1H NMR analysis indicated that TA was transformed into gallic acid (GA), EA and pyrogallol. Biopolymer (EPS and PHB) production was decreased several folds in the presence of TA compared with cells grown in only glucose medium.

Conclusions

This is the first evidence on the biotransformation of TA by Azotobacter and also elevated level of EA production from gallotannins. Azotobacter has developed the mechanism to utilize TA for their carbon and energy source.

Significance and Impact of the Study

The widespread occurrence and exploitation of Azotobacter sp. strain SSB81 in agricultural and forest soil have an additional advantage to utilize the soil‐accumulated TA and detoxifies the allelopathic effect of constant accumulated TA in soil.  相似文献   

5.
Gallic acid (3,4,5-trihydroxybenzoic acid, GA) is a naturally occurring plant phenol. In vitro and in vivo studies have shown that this phytochemical protected DNA and membranes against ionizing radiation. Rat liver microsomes and plasmid pBR322 DNA were exposed to various doses of gamma radiation in presence and absence of GA. Exposure of the microsomes to gamma radiation resulted in the formation of peroxides of membrane lipids measured as thiobarbituric acid reactive substances and presence of GA during irradiation prevented the formation of lipid peroxidation. Gamma irradiation of plasmid DNA resulted in induction of strand breaks in DNA resulting in disappearance of the supercoiled (ccc) form. Presence of GA during irradiation protected the DNA from undergoing the strand breaks. In in vivo studies it was found that whole body exposure of mice to gamma radiation (4 Gy) increased the formation of lipid peroxides in various tissues and damage to cellular DNA (as measured by alkaline comet assay) in peripheral blood leucocytes. Administration of GA to mice prior to whole body radiation exposure reduced the peroxidation of lipids and the damage to the cellular DNA indicating in vivo radiation protection of membranes and DNA by GA. (Mol Cell Biochem 278: 111–117, 2005)  相似文献   

6.
AIMS: The aim of this study was to enrich and isolate bacteria from a tannery soil that were capable of utilizing tannic acid and gallic acid as sole source of carbon aerobically, and to characterize their diversity in order to identify efficient strains that can be used for tannin bioremediation. METHODS AND RESULTS: Bacterial strains were isolated after enrichment in minimal medium with tannic acid or gallic acid as sole carbon source. Polymerase chain reaction (PCR) restricted fragment length polymorphism of 16S rDNA [amplified ribosomal DNA restriction analysis (ARDRA)] and BOX-PCR was used to characterize their diversity. Two strains showing relatively high efficiency in degrading tannic acid and gallic acid were identified on the basis of carbon source utilization pattern (BIOLOG) and 16S rDNA sequence. CONCLUSIONS: Bacterial strains capable of degrading tannic acid and gallic acid could be grouped into six and seven clusters on the basis of ARDRA and BOX-PCR, respectively. On the basis of 16S rDNA sequence, the most efficient isolate degrading tannic acid belonged to Pseudomonas citronellolis, whereas the most efficient gallic acid degrader showed maximum phylogenetic relatedness to P. plecoglossicida. SIGNIFICANCE AND IMPACT OF THE STUDY: Aerobic tannic acid degraders such as the two strains isolated in this study can be used for tannin bioremediation, and in the study of genes involved in the production of tannase, an industrially important enzyme.  相似文献   

7.
该研究采用高效液相色谱法和紫外分光光度法分别对拳参中的主要成份———没食子酸以及总鞣质进行含量测定。其中,用高效液相色谱法测定没食子酸的含量,HPLC 条件为 Hypersil GOLD Phenyl 柱(250 mm ×4.6 mm,5μm),甲醇-0.1%磷酸梯度洗脱,流速为1.0 mL?min-1,检测波长为276 nm。用紫外分光光度法测定总鞣质的含量,采用2010版《中国药典》一部附录 XB 中鞣质含量测定方法,用干酪素沉淀鞣质,通过干酪素沉淀前后鞣质的变化来确定样品中总鞣质的含量。结果表明:没食子酸在0.051~1.02μg 范围内呈现良好的线性关系,平均加样回收率分别为99.1%、100.3%、101.9%,RSD 分别为2.1%、0.8%、2.0%;总鞣质在2.09~10.48μg 范围内呈现良好线性关系,平均加样回收率分别为102.2%、100.2%、102.1%,RSD 分别为1.3%、1.4%、1.0%。利用上述方法,还测定了贵州贵阳和四川成都各3批样品中没食子酸和总鞣质的含量差异,发现成都样品中的没食子酸与总鞣质均大于贵阳拳参中的含量,初步分析导致这一结果的原因可能与拳参的生长海拔有关,而成都的海拔范围更适合拳参的生长。上述两种方法快速、简单、重现性好,可以作为拳参中没食子酸和总鞣质的含量测定方法,而该方法也是首次被用来同时测定拳参中没食子酸和总鞣质的含量,为今后的地方药典标准甚至《中国药典》标准的补充和完善提供了重要依据。  相似文献   

8.
Aims: The anti‐enterovirus 71 (EV71) activity of six Nepalese plants’ extracts and gallic acid (GA) isolated from Woodfordia fruticosa Kurz (family; Lythaceae) flowers were evaluated in Vero cells. Methods and Results: The anti‐EV71 activity of tested compounds was evaluated by a cytopathic effect reduction method. Our results demonstrated that flowers’ extracts of W. fruticosa exerted strong anti‐EV71 activity, with a 50% inhibitory concentration (IC50) of 1·2 μg ml?1 and no cytotoxicity at a concentration of 100 μg ml?1, and the derived therapeutic index (TI) was more than 83·33. Rivabirin showed no antiviral activity against EV71. Furthermore, GA isolated from W. fruticosa flowers exhibited a higher anti‐EV71 activity than the extract of W. fruticosa flowers, with an IC50 of 0·76 μg ml?1 and no cytotoxicity at a concentration of 100 μg ml?1, and the derived TI was 99·57. Conclusions: This study demonstrated that flower extracts of W. fruticosa possessed anti‐EV71 activity and GA isolated from these flowers showed stronger anti‐EV71 activity than that the extracts. Significance and Impact of the Study: Our results suggest that the GA from W. fruticosa flowers may be used as a potential antiviral agent.  相似文献   

9.
In routine assay for the screening of microbes producing proteases, 10% trichloroaceticacid (TCA) is flooded on the milk agar plates after inoculation and required incubation to precipitate the protein. However, the clarity of the hydrolyzed zone is not very sharp and distinct. We herein present an improved assay for detecting the presence of extracellular protease from microorganisms on agar plates. In this method 10% tannic acid is flooded on the milk agar plate (in place of, TCA) to observe the zone of hydrolysis. Tannic acid sharply increases the colour intensity of the plate, as it favours the precipitation of the unhydrolyzed protein in the plate, thereby improving the contrast between the intact zones and the enzymatic lyses zones of the substrate. Our results indicate that this method is useful to detect extracellular proteases produced by both fungi as well as bacteria. The method used in the present study is sensitive, and can be easily performed for screening of large number of microbial cultures. This is the first report on the use of tannic acid for the detection of microbial proteases.  相似文献   

10.
Summary Ruthenium red staining and tannic acid fixation were used to analyse the fine structure of embryonic mouse dental basement membrane in intact first mandibular molars or in EDTA-isolated dental papillae. Preameloblasts are separated from extracellular matrix proper by a basal lamina that contains regularly arranged proteoglycan granules of about 10 nm in diameter. This distribution pattern is particularly evident in the inner and outer lamina rara of the basal lamina associated with EDTA-isolated dental papillae. The plasmalemma of preameloblasts demonstrates electron dense plaques on the inner leaflet. Ruthenium red positive granules (50 nm in diameter) coat non-striated and striated fibrils of the matrix. Hyaluronidase treatment digested the ruthenium red positive granules. Tannic acid fixation allowed the demonstration of filaments within the lamina rara interna, connecting the lamina densa with plasmalemma of preameloblasts. These observations are discussed in the context of the terminal differentiation of odontoblasts.These studies were supported by INSERM, grant n 537785 and DGRST  相似文献   

11.
Aims:  The aim of the study was to isolate the endophytic fungi from Acer ginnala and screen isolates rich in gallic acid.
Methods and Results:  After epiphytic sterilization, 145 fungal endophytes were isolated from the stem, annual twig and seed of Acer ginnala . The endophytes were grouped into ten different taxa, Phomopsis sp., Neurospora sp., Phoma sp., Epicoccum sp., Penicillium sp., Alternaria sp., Fusarium sp., Trichoderma sp., Cladosporium sp. and a species of Pleosporales Incertae Sedis , by their morphological traits and ITS-rDNA sequence analysis. The content and yield of gallic acid of 141 isolates were determined by HPLC. On average, the species of Pleosporales Incertae Sedis had the highest content and yield of gallic acid (13·28 mg g−1 DW; 119·62 mg l−1), while Alternaria sp. had the lowest.
Conclusions:  Of 141 fungal endophytes from A. ginnala , Phomopsis sp. isolate SX10 showed both the highest content and the highest yield of gallic acid (29·25 mg g−1 DW; 200·47 mg l−1).
Significance and Impact of the Study:  Endophytic fungi isolated from A. ginnala may be used as potential producers of gallic acid and other compounds with biological activities, or functioned as elicitors to produce natural compounds.  相似文献   

12.
为探索没食子酸对胡桃醌的媒染机理,本实验通过比较在没食子酸存在的条件下,胡桃醌在头发上的染色效果和吸附性能,并利用量子化学计算没食子酸对胡桃醌和头发之间相互作用能的影响。结果表明,没食子酸可以使胡桃醌染出的发色更加鲜亮并且拥有更强的色牢度;同时没食子酸还可以改变胡桃醌的吸附行为,增加胡桃醌的吸附总量;在分子水平上,没食子酸可以充当桥梁连接头发角蛋白和胡桃醌,使得整体具备的能量更低,所形成的氢键更加稳定。说明没食子酸可以充当媒染剂增强胡桃醌的染色性能,本研究为天然媒染剂的选取提供了理论基础。  相似文献   

13.
ObjectiveTo determine the effect of phytic acid, tannic acid and pectin on fasting non-heme iron bioavailability in both the presence and absence of calcium.Research methodsTwenty-eight apparently healthy adult females participated in two iron absorption studies using radioactive iron isotopes (59Fe and 55Fe). One group received 5 mg of iron (as FeSO4) alone (control), together with 10 mg of phytic acid, 100 mg of tannic acid and 250 mg of pectin (study A), on different days. The second group received the same iron doses and compounds as the other group, plus 800 mg of calcium (CaCl2) (study B). The compounds were administered after an overnight fast, and no food or beverages were consumed for the following 3 h. Iron status and circulating radioactivity were measured in venous blood samples.ResultsThe geometric means of iron bioavailability (range ± 1SD) for iron alone, iron with phytic acid, iron with tannic acid, and iron with citrus pectin were 25.0% (11.9–52.0); 18.9% (9.9–35.8); 16.8% (8.7–32.3); and 21.1% (10.2–43.9), respectively (repeated-measures ANOVA, p < 0.02 (Dunnett's post hoc: control vs tannic acid p < 0.05). When 800 mg of calcium was added (study B), iron bioavailability was 16.7% (10.1–27.5); 13.2% (7.1–24.6); 14.8% (8.8–25.1); and 12.6% (5.5–28.8), respectively (repeated-measures ANOVA, NS).ConclusionsTannic acid decreases the fasting bioavailability of non-heme iron, however this effect did not exist in the presence of calcium. No effect was observed by phytic acid or citrus pectin on fasting non-heme iron bioavailability in both the presence and absence of calcium.  相似文献   

14.
The distinctive and unique features of gallic acid metabolism in plants are discussed and recent observations on new metabolites are presented. The potential application of these results to taxonomic questions is outlined.  相似文献   

15.
First a kind of fermented tea wine was prepared from Dancong tea. The content of four major catechins and gallic acid (EC, EGC, EGCG and ECG) in tea wine was measured with HPLC. The results showed that the content of EC, EGC, EGCG, ECG and catechins in tea wine decreased when compared with that before fermentation. The content of EC decreased the most, reaching 26.79%, while the content of GA changed the least with a decrease of only 13.56%. Nevertheless, tea wine still contains a relatively large amount of catechins, thus proper consumption of tea wine may be salubrious.  相似文献   

16.
This study examined the ability of methyl gallate (MG) and gallic acid (GA), the main compounds of gallo-tannins in Galla Rhois, to inhibit the proliferation of oral bacterial and the in vitro formation of Streptococcus mutans biofilms. The antimicrobial activities of these compounds were evaluated in vitro using the broth microdilution method and a beaker-wire test. Both MG and GA had inhibitory effects on the growth of cariogenic (MIC<8 mg/ml) and periodontopathic bacteria (MIC=1 mg/ml). Moreover, these compounds significantly inhibited the in vitro formation of S. mutans biofilms (MG, 1 mg/ml; GA, 4 mg/ml; P<0.05). MG was more effective in inhibiting bacterial growth and the formation of S. mutans biofilm than GA. In conclusion, MG and GA can inhibit the growth of oral pathogens and S. mutans biofilm formation, and may be used to prevent the formation of oral biofilms.  相似文献   

17.
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   

18.
19.
The metabolism of vulpinic acid by an unclassified soil micro-organism was studied. A new compound, 2,5-diphenyl-3-hydroxy-4-oxo-2-hexendioic acid (DHOHA) was isolated from the reaction mixture of a cell-free preparation and pulvinic acid. The existence of a hydrolase which catalyses the conversion of vulpinic acid to pulvinic acid was detected in cell-free preparation, and an inducible lactone hydrolase capable of converting pulvinic acid to DHOHA was purified 130-fold and characterized. This enzyme had a MW of ca 34 000, a Km for pulvinic acid at pH optimum (pH 7.0) less than 10 ? 6 M, pI = 5.0, and was inhibited by p-chloromercuriphenylsulfonate and diethylpyrocarbonate. The enzyme was highly specific for pulvinic acid. The initial degradative steps proposed for this organism are vulpinic acid → pulvinic acid → DHOHA.  相似文献   

20.
Tannase production by Aspergillus niger Aa-20 was studied in submerged (SmF) and solid-state (SSF) fermentation systems with different tannic acid and glucose concentrations. Tannase activity and productivity were at least 2.5 times higher in SSF than in SmF. Addition of high tannic acid concentrations increased total tannase activity in SSF, while in SmF it was decreased. In SmF, total tannase activity increased from 0.57 to 1.03 IU/mL, when the initial glucose concentration increased from 6.25 to 25 g/L, but a strong catabolite repression of tannase synthesis was observed in SmF when an initial glucose concentration of 50 g/L was used. In SSF, maximal values of total tannase activity decreased from 7.79 to 2.51 IU when the initial glucose concentration was increased from 6.25 to 200 g/L. Kinetic results on tannase production indicate that low tannase activity titers in SmF could be associated to an enzyme degradation process which is not present in SSF. Tannase titers produced by A. niger Aa-20 are fermentation system-dependent, favoring SSF over SmF. Journal of Industrial Microbiology & Biotechnology (2001) 26, 296–302. Received 07 July 2000/ Accepted in revised form 15 February 2001  相似文献   

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