首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
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   

2.
为了建立金樱根中没食子酸和儿茶素含量的测定方法,分析广西不同产地金樱根及炮制品中没食子酸和儿茶素含量的变化,该文以没食子酸和儿茶素的含量作为指标成分,采用HPLC法对广西产金樱根生品、炒炙品、酒炙品、盐炙品及醋炙品进行测定,并采用SPSS 23.0软件进行方差分析和聚类分析。结果表明:广西不同产地金樱根及炮制品中没食子酸和儿茶素含量均存在差异,所有样品中儿茶素的含量均比没食子酸高,南部地区(除贵港桂平外)的没食子酸和儿茶素含量整体上比北部地区高,在炮制品中醋炙后没食子酸和儿茶素含量最高。该研究表明HPLC测定方法简单可行,金樱根中没食子酸和儿茶素含量的变化差异主要表现为产地地域及炮制方法的不同,可为今后金樱根资源的合理利用、质量标准制定以及临床用药的研究提供一定科学依据。  相似文献   

3.
The intermediary metabolism of gallic acid by Aspergillus niger under the influence of some added inhibitors has been studied. The decomposition of gallic acid by lyophilized cells under fluoroacetate inhibition allowed cis-aconitic acid, α-ketoglutaric acid and citric acid to accumulate. A mechanism of gallic acid decomposition via cis-aconitic acid has been inferred.  相似文献   

4.
Aim: To complete our study on tannin degradation via gallic acid by the biotechnologically interesting yeast Arxula adeninivorans as well as to characterize new degradation pathways of hydroxylated aromatic acids. Methods and Results: With glucose‐grown cells of A. adeninivorans, transformation experiments with hydroxylated derivatives of benzoic acid were carried out. The 12 metabolites were analysed and identified by high performance liquid chromatography and GC/MS. The yeast is able to transform the derivatives by oxidative and nonoxidative decarboxylation as well as by methoxylation. The products of nonoxidative decarboxylation of protocatechuate and gallic acid are substrates for further ring fission. Conclusion: Whereas other organisms use only one route of transformation, A. adeninivorans is able to carry out three different pathways (oxidative, nonoxidative decarboxylation and methoxylation) on one hydroxylated aromatic acid. The determination of the KM‐values for protocatechuate and gallic acid in crude extracts of cells of A. adeninivorans cultivated with protocatechuate and gallic acid, respectively, suggests that the decarboxylation of protocatechuate and gallic acid may be catalysed by the same enzyme. Significance and Impact of the Study: This transformation pathway of protocatechuate and gallic acid via nonoxidative decarboxylation up to ring fission is novel and has not been described so far. This is also the first report of nonoxidative decarboxylation of gallic acid by a eukaryotic micro‐organism.  相似文献   

5.
Hypertension causes cardiac hypertrophy and leads to heart failure. Apoptotic cells are common in hypertensive hearts. Ca2+/calmodulin‐dependent protein kinase II (CaMKII) is associated with apoptosis. We recently demonstrated that gallic acid reduces nitric oxide synthase inhibition‐induced hypertension. Gallic acid is a trihydroxybenzoic acid and has been shown to have beneficial effects, such as anti‐cancer, anti‐calcification and anti‐oxidant activity. The purpose of this study was to determine whether gallic acid regulates cardiac hypertrophy and apoptosis in essential hypertension. Gallic acid significantly lowered systolic and diastolic blood pressure in spontaneously hypertensive rats (SHRs). Wheat germ agglutinin (WGA) and H&E staining revealed that gallic acid reduced cardiac enlargement in SHRs. Gallic acid treatment decreased cardiac hypertrophy marker genes, including atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), in SHRs. The four isoforms, α, β, δ and γ, of CaMKII were increased in SHRs and were significantly reduced by gallic acid administration. Gallic acid reduced cleaved caspase‐3 protein as well as bax, p53 and p300 mRNA levels in SHRs. CaMKII δ overexpression induced bax and p53 expression, which was attenuated by gallic acid treatment in H9c2 cells. Gallic acid treatment reduced DNA fragmentation and the TUNEL positive cells induced by angiotensin II. Taken together, gallic acid could be a novel therapeutic for the treatment of hypertension through suppression of CaMKII δ‐induced apoptosis.  相似文献   

6.
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   

7.
A bacterial strain, which was isolated from soil, and identified as Citrobacter sp., showed an inducible gallic acid decarboxylase activity producing pyrogallol from gallic acid. The strain also decarboxylated protocatechuic acid, pyrocatechuic acid, 3,5-dihydroxybenzoic acid and m-hydroxybenzoic acid as well. The pyrogallol and pyrocatechol produced were isolated from the cultured broths to which gallic acid and protocatechuic acid were added, respectively.  相似文献   

8.
Microbial production of gallic acid by modified solid state fermentation   总被引:4,自引:0,他引:4  
Bioconversion of tannin to gallic acid from powder of teri pod (Caesalpinia digyna) cover was achieved by the locally isolated fungus, Rhizopus oryzae, in a bioreactor with a perforated float for carrying solid substrate and induced inoculum. Modified Czapek-Dox medium, put beneath the perforated float, with 2% tannic acid at pH 4.5, temperature 32°C, 93% relative humidity, incubated for 3 days with 3-day-old inoculum was optimum for the synthesis of tannase vis-à-vis gallic acid production. Conversion of tannin to gallic acid was 90.9%. Diethyl ether was used as the solvent for extraction of gallic acid from the fermented biomass. Received 14 December 1998/ Accepted in revised form 17 June 1999  相似文献   

9.
Melon fruit fly, Bactrocera cucurbitae (Coquillett) is an important pest of cucurbits and other vegetable crops. It is not only a serious pest of cucurbit crops but sometimes also attacks non-host plants. In an endeavour to explore secondary metabolites as important and safe means of pest management, we investigated the effects of gallic acid, a phenolic compound, on the growth and development of melon fruit fly, B. cucurbitae. Larval survival and emergence were severely affected by gallic acid treatment. Both decreased in a concentration dependent manner with increase in concentration. Gallic acid-treated larvae took longer duration to pupate and reach the adult stage as compared to control larvae. Inhibitory effects of gallic acid were also observed on larval weight, pupal weight, mean relative growth rate and food assimilated which decreased with treatment. The ability of gallic acid to disrupt the development of B. cucurbitae suggests that the phenolic compound might have caused oxidative stress in the body of the insect.  相似文献   

10.
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   

11.
Gallic acid, a polyphenyl class natural product from gallnut and green tea, is known to be antioxidant, anti‐inflammatory and radical scavenger. In this study, we aimed to investigate the possible protective effects of gallic acid on paraoxonase and arylesterase activities in liver exposed to acute alcohol intoxication. Paraoxonase and arylesterase activities in liver tissue and serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were measured. Histological investigations were also made. In our study, we observed a significant increase of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, which are indicators of liver damage after acute ethanol consumption. Gallic acid therapy has significantly reduced the increase in these biomarkers, indicating a possible hepatoprotective effect of gallic acid. Ethanol consumption caused a significant decrease in liver paraoxonase activity (P < 0.001). Gallic acid treatment partly restored this decreased paraoxonase activity, which resulted from ethanol administration. A gallic acid dose of 100 mg/kg was observed as highest restoring effect for paraoxonase activity (P < 0.05). The activity of arylesterase was decreased in the ethanol group as compared with the control group, but this was not significant. However, 50 mg/kg of gallic acid treatment restored the loss of this activity due to ethanol exposure (P < 0.001). We observed that gallic acid ameliorates the liver damage caused by excessive alcohol consumption in a dose‐dependent way. Our results in this study showed that gallic acid might have a protective effect against alcoholic liver disease. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

12.
Tannin acyl hydrolase (EC 3.1.1.20) of Asp. oryzae No. 7 hydrolyzes tannic acid to glucose and gallic acid. The intermediate hydrolyzates are 1,2,3,4,6-pentagalloyl glucose, 2,3,4,6-tetragalloyl glucose and two kinds of monogalloyl glucose.

The enzyme hydrolyzes ester compounds of gallic acid, but does not hydrolyze any other substrate analogues such as methyl-resorcyrate.

The enzyme reaction is inhibited competitively by substrate analogues which have phenolic hydroxyls with the exception that 2,6-dihydroxy benzoic acid inhibits noncompetitively. Therefore the binding site of the enzyme may be able to react with any kind of phenolic hydroxyl, although the substrate forming a true ES-complex must be an ester compound of gallic acid.  相似文献   

13.
The English grain aphid, Sitobion avenae (Fabricius) (Hemiptera: Aphididae), is a significant pest of cereal crops, but molecular factors and mechanisms that underpin its ability to develop differential biotypes on variable host plants are still not well understood. In this study, we investigated the interactions between two plant secondary metabolites (i.e., gramine and gallic acid) and three glutathione S-transferases (GSTs) of S. avenae. Using artificial diets complemented or not with one of these two plant compounds, we found that gramine had relatively stronger negative effects on fitness of S. avenae biotype 3 (adapted to barley), and gallic acid on that of biotype 4 (adapted to wheat). Gramine significantly induced overexpression of SaveGST1 and SaveGST2 in biotype 4, but not in biotype 3. Gramine also reduced SaveGST3 expression in biotype 4, but not in biotype 3, suggesting biotype-specific effect of GSTs’ regulation. In the treatments with gallic acid, the overexpression of SaveGST1, but not SaveGST2 or SaveGST3, was significantly induced in both biotypes, suggesting a critical role of SaveGST1 in detoxification of phenolic compounds such as gallic acid. The total constitutive GST activity was much higher in biotype 4 than in biotype 3. Significant increase in GST activity was obtained by the addition of both secondary metabolites in biotype 4, but not in biotype 3, showing significantly higher expression plasticity of GSTs in biotype 4. Thus, both constitutive and induced expression of GSTs could affect the adaptability of S. avenae on plants with variable secondary compounds, and thus contribute to the divergence of biotypes in this aphid species.  相似文献   

14.
Low‐light environments in early‐successional forests that have established after abandonment of farming often restrict the establishment of later successional species resulting in an arrested succession. This 6‐year study tested the potential of different canopy manipulations to facilitate the establishment of a light‐demanding canopy tree species, tōtara (Podocarpus totara), within a regenerating kānuka (Kunzea robusta) stand. Results highlighted the effectiveness of artificial gaps over other methods (ring‐barking and edge‐planting) in accelerating the growth of planted tōtara. Seedlings under gaps grew consistently taller and faster over time indicative of an improved understorey light environment. Ring‐barking did not have a significant effect on tōtara growth because only a portion of the treated trees died, and after 6 years dead trees remained standing with intact branches resulting in insignificant increases in light transmission. At the forest edge sites, tōtara growth was highly variable. Although some seedlings grew as tall as in the gaps, others did not. Survival was also lower in the edge sites than in other treatments, which was likely due to enhanced herbivory from ungulates which impacted some plants at these sites. Gap creation is likely to be an important tool for restoring late‐successional canopy species in regenerating stands both through providing ideal sites for the growth of light‐demanding species such as tōtara and through natural establishment of other future canopy trees into the gaps.  相似文献   

15.
A sulfotransferase (ST) which catalyzes the transfer of sulfate from 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to gallic acid glucoside was characterized from microsomal preparations of Mimosa pudica. The product of the reaction was found to co-elute on HPLC with the periodic leaf movement factor 1 (PLMF-1) (gallic acid β-d -gluco-pyranosyl-6′-sulfate). The distribution of the enzyme activity was restricted to plasma membrane preparations from primary, secondary and tertiary pulvini. The M. pudica ST activity was inhibited in a dose-dependent manner in the presence of an antibody raised against the flavonol 3-sulfotransferase of Flaveria chloraefolia, suggesting structural similarities between the two proteins. Western blot analysis of M. pudica protein extracts using these antibodies indicated the presence of a cross-reactive polypeptide with an apparent molecular mass of 42 000 Da whose distribution correlates with the presence of the gallic acid glucoside ST activity. Indirect immunogold labeling of resin-embedded sections from tertiary pulvini showed a specific localization of gold particles on the sieve-tube plasma membranes. The label distribution was uniform and other cellular organelles and membrane systems displayed little or no labeling. The results of the Western blot and immunocytochemical studies are consistent with the detection of the gallic acid glucoside ST activity in plasma membrane preparations of M. pudica pulvini cells. The specific tissue distribution of the ST in motor organ phloem cells suggests that this is the site of synthesis and/or accumulation of PLMF-1 and supports the proposed hypothesis that PLMF-1 may be acting as a chemical signal during the seismonastic response of M. pudica.  相似文献   

16.
The frequency ofhis + revertants induced by N-methyl-N-nitrosourea (MNU) and N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) in the strain TA100 ofSalmonella typhimurium was decreased by gallic and tannic acid. In weak buffer solutions, the inhibition effects of gallic acid towards MNU and MNNG mutagenicity was caused primarily by a decrease of pH in the incubation mixtures. At adjusted pH (pH 5.0 and 6.5), the antimutagenic effects are largely the result of an interaction between MNU or MNNG with phenolic acids outside the cells.  相似文献   

17.
Weinkove, D., Poyatos, J. A., Greiner, H., Oltra, E., Avalos, J., Fukshansky, L., Barrero, A. F., and Cerdá-Olmedo, E. 1998. Mutants ofPhycomyceswith decreased gallic acid content.Fungal Genetics and Biology25, 196–203. Most plants and some fungi accumulate phenols. Two hydroxybenzoic acids, gallic and protocatechuic acids, are abundant in the giant sporangiophores of the zygomycetePhycomyces blakesleeanus,much more so than in the basal mycelium or the culture medium. The actual concentrations vary with illumination, age of the culture, and composition of the medium. We devised a simple screening procedure to isolatehbamutants whose sporangiophores contained less gallic acid than the wild type. The most useful mutant had very low concentrations of hydroxybenzoic acids in the sporangiophores, but about the same as the wild type in the basal mycelium and the medium. The mutant was only slightly different from the wild type in growth and morphology. Mutant and wild-type sporangiophores grew away from ultraviolet C sources (260 nm) equally well. Contrary to previous conjectures, ultraviolet tropism does not depend on the ultraviolet absorption of gallic acid or other free hydroxybenzoic acids in the sporangiophore. Against expectations, phenols did not impair DNA extraction: sporangiophores produced better DNA preparations than basal mycelia and thehbamutant only slightly better than the wild type.  相似文献   

18.
The present study concerns the genotoxicity of olive mill waste water (OMWW) generated in mills producing olive oil in Morocco. The Vicia faba micronucleus test was used to evaluate the genotoxicity of OMWW and the six major phenolic compounds identified by HPLC in this effluent. Five dilutions of OMWW were tested: 0.1, 1, 5, 10 and 20%. Maleic hydrazide was used as a positive control. The results showed that OMWW was genotoxic at 10% dilution. In order to investigate the components involved in this genotoxicity, the six major phenols present in this effluent, oleuropein, gallic acid, 4-hydroxyphenyl acetic acid, caffeic acid, paracoumaric acid and veratric acid, were studied at concentrations corresponding to the genotoxic concentration of the OMWW itself. Two phenols, gallic acid and oleuropein induced a significant increase in micronucleus frequency in Vicia faba; the four other phenols had no significant genotoxic effect. These results suggest that under the experimental conditions of our assay, OMWW genotoxicity was associated with gallic acid and oleuropein.  相似文献   

19.
A spectrophotometric method to determine gallic acid, residual gallotannin and tannin acyl hydrolase (EC 3.1.1.20) activity during microbial hydrolysis of pentagalloyl glucose is described. The following equations have been developed to estimate gallotannin and gallic acid in the incubation medium by absorbance measurements at two different wavelengths: concentration of gallotannin (g ml-1)=34.41 (A293.8)–6.98 (A254.6); concentration of gallic acid (g ml-1)=21.77 (A254.6)–17.17 (A293.8). As compared to Aspergillus and Penicillium, the fungal genera extensively studied for the production of this enzyme, Fusarium solanii and Trichoderma viride exhibited higher enzyme activity showing approximately 88 and 84 mole percent conversion respectively after a 24 h incubation period.The authors are with the School of Life Sciences, Devi Ahilya University, Vigyan Bhawan, Khandwa Road Campus, Indore-452 001, India.  相似文献   

20.
Summary Tannins limit the use of fodder trees as feed for ruminants. Removal of the effects of tannins would thus improve the nutritional quality of these trees. This prompted the study to evaluate the effect of rumen or faecal mixed cultures from different animals on tannin degradation. Tannin extracts, tannic acid and gallic acid were used to enrich media to assess if rumen or faecal mixed cultures could degrade the phenolic compounds. Rumen fluid of Acacia-adapted sheep, sheep fed on wheat bran, bush duikers (Sylvicapra grimmia) and goats fed on Leucaena pallida and Sesbania goetzei were separately inoculated into Growth Study Medium (GSM) and incubated for 5-15 days. Faecal samples from dikdik (Madoqua guentheri), camel (Camelus dromedarius), zebra (Equus quagga), Grant’s gazelle (Gazella granti) and hartebeest (Alcelaphus buselaphus) were also separately inoculated into GSM media and incubated from 3-5 days. TLC results showed that mixed cultures from rumen fluids of Acacia-adapted sheep, sheep on wheat bran, goats on Leucaena pallida and Sesbania goetzei partially hydrolysed tannic acid to pyrogallol. Complete degradation of the heterocyclic ring in tannic acid and gallic acid was achieved by the mixed cultures from the faecal samples of dikdik and this was confirmed by HPLC. Mixed cultures from faecal samples of camel hydrolysed gallic acid to phloroglucinol. This study has demonstrated that faecal microorganisms of Ethiopian dikdik could completely degrade hydrolysable tannin.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号