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Herba Epimedii′s biotransformation in vitro simulated gastrointestinal digestion and faecal fermentation systems
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作者 LI Ben ZHANG Xiao-yao +1 位作者 Alberto CP DIAS ZHANG Xiao-ying 《中国药理学与毒理学杂志》 CAS 北大核心 2021年第10期732-732,共1页
OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This... OBJECTIVE Epimedium is rich in a variety of beneficial active ingredients,and has been widely used in the ethnopharmacological practices,however,its biotransformation in gastrointestinal digestions remain unclear.This study aimed to investigate the dynamic changes of components and biological activity of Epimedium in the in vitro simulated digestion and subsequent human faecal fermentation.METHODS The models of in vitro simulated saliva,gastric and intestinal digestion,as well as colonic fermentation were constructed to simulate the digestion process of Epimedium.The dynamic changes of components of Epimedium during the simulated digestions in vitro and subsequent human faecal fermentation were investigated by UPLC-MS,HPLC-DAD combined with principal component analysis(PCA)and multi-ingredient quantitative analysis.RESULTS A variety of metabolites with high contents were produced after 0.5 h of intestinal digestion and colonic fermentation 0.5 h.Application of PCA to HPLC data showed the obvious separation of colonic fermentation 0.5 h stage samples from other colonic fermentation stages samples(24,48 and 72 h).Additionally,non-digestion and saliva digestion stage samples clustered together,and there was obvious separation between intestinal digestion samples and gastric digestion samples.The contents of epimedium C,icariin and baohuside I all increased significantly after intestinal digestion[58.70±7.08,47.15±5.68 and(12.78±0.55)mg·g^(-1)]compared with gastric digestion[29.00±5.65,17.40±4.55 and(2.77±0.19)mg·g^(-1)].There were significant differences between sample after 0.5 h of colonic fermentation[64.22±9.32,51.26±6.33 and(16.68±3.19)mg·g^(-1)]and other time points(24,48 and 72 h)in components and the contents of active ingredient,and the content of these components all decreased with the fermentation time.The ability of scavenging ABTS free radicals[IC50=(0.29±0.02)g·L^(-1)]increased significantly compared with gastric digestion[(1.57±0.02)g·L^(-1)],and after 0.5 h of colonic fermentation,the ability also increased significantly.CONCLUSION Gastrointestinal digestion had a significant impact on the contents of active components in Epimedium,and the metabolism of these components mainly occurred in the colon.The intestinal digestion and colonic fermentation significantly improved the anti-ABTS activity of epimedium. 展开更多
关键词 EPIMEDIUM simulated gastrointestinal digestion faecal fermentation biotransformation
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Biotransformation of Gastrodin by Cell Suspension Cultures of Catharanthus roseus 被引量:9
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作者 戴均贵 巩卓 +3 位作者 朱丹萌 郭洪祝 郑俊华 果德安 《Acta Botanica Sinica》 CSCD 2002年第3期377-378,共2页
应用长春花 (Catharanthusroseus (L .)G .Don)悬浮细胞培养体系对天麻素进行了生物转化反应研究。经过8d培养形成一个转化产物 ,应用光谱方法鉴定转化产物的结构为对羟基苯甲醇 ,为天麻素水解后形成的甙元。
关键词 GASTRODIN biotransformation cell suspension cultures Catharanthus roseus
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Biotransformation of Gastrodin by Mucor spinosus 被引量:4
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作者 占纪勋 郭洪祝 +2 位作者 戴均贵 张元兴 果德安 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期187-189,共3页
Microbial transformation of gastrodin by Mucor spinosus strain 3.3450, resulted in a product with a transformation rate close to 100 per cent. This product was identified as p-hydroxy benzyl alcohol on the basis of it... Microbial transformation of gastrodin by Mucor spinosus strain 3.3450, resulted in a product with a transformation rate close to 100 per cent. This product was identified as p-hydroxy benzyl alcohol on the basis of its 1H, 13C NMR and EI-MS spectral data. It could be inferred that the enzyme responsible for the biotransforma-tion reaction was a kind of extracellular and constitutive enzyme since the transformation reaction of the substrate could be carried out in cell free extracts of the fermentation broth of the Mucor spinosus. 展开更多
关键词 Mucor spinosus biotransformation GASTRODIN p-Hydroxy benzyl alcohol
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RELATIONSHIP BETWEEN GROWTH AND MORPHOLOGY OF METARRHIZIUM ANISOPLIAE IN BIOTRANSFORMATION OF STEROID 被引量:2
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作者 阳葵 李晓静 +2 位作者 王积分 段世铎 张鎏 《Transactions of Tianjin University》 EI CAS 2001年第1期1-6,共6页
The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled t... The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled to growth phases:the fractal dimension,a feature calculated from the morphological images,increases during the late lag phase and the early exponential phase,and culminates at a value near 2.4 at half of the exponential phase.This can be attributed to the marked change of rough and smooth pellet proportions during growth and the change can be well expressed by the fractal analysis of mycelial morphology.The mycelial morphology is also strongly related to the biotransformation activity:a mycelial sample was withdrawn from the culture to use for fractal analysis before the steroid substrate (16α,17α epoxy 4 pregnene 3,20 dione) was added;the higher fractal dimension corresponds to the higher conversion rate of steroid biotransformation.And the maximum of fractal dimension appeared prior to the maximum of biomass concentration.It is therefore possible to utilize the fractal dimension curve to supervise the fermentation process more timely and availably than to use the conventional biomass curve to do. 展开更多
关键词 metarrhizium anisopliae MORPHOLOGY GROWTH fractal dimension biotransformation STEROID
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Study on Anti-oxidation and Inhibitory Effect on Nonenzymatic Glycation Reaction of Fermentation Extract from Biotransformation of Ginkgo biloba L. (EGB) by Hericium erinaceus 被引量:3
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作者 黄达明 常为众 +3 位作者 张志才 崔凤杰 肖香 钱静亚 《Agricultural Science & Technology》 CAS 2008年第2期10-13,共4页
[ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ab... [ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ability and reducing capacity of DPPH as well as inhibitory rate of nonenzymatic glycation reaction were measured targets for comparing changes of anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of fermentation lyophilizer and fermentation extraction before and after EGB fermention adsorbed by AB-8 macroporous resin. The EGB fermention was biotransformed by Hericium erinaceus. [ Result ] After adsorbed by AB-8 macroporous resin, the bioactive matters were concentrated and separated. The free radical scavenging rate, reducing capacity and inhibitory rate of nonenzymatic glycation reaction were increased significantly after adsorbed by AB-8 macroporous resin. [ Conclusion] AB-8 macroporous resin could be used for preliminary concentration of EGB fermentation which was biotransformed by Hericium erinaceus. 展开更多
关键词 biotransformation ANTI-OXIDATION Nonenzymatic glycation reaction
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Biotransformation of Artemisinin by Hairy Root Cultures of Rheum palmatum L. 被引量:3
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作者 李莉欣 苏艳芳 +1 位作者 刘晓峰 果德安 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期122-124,共3页
The biotransformation of artemisinin by hairy root cultures ofRheum palmatum L. was investigated for the first time. The main product, deoxyartemisinin, was isolated and characterized on the basis of its spectral data.
关键词 ARTEMISININ Deoxyartemisinin Rheum palmatum hairy root cultures biotransformation
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Technologies of Seperating and Exactly 11-α-Hydroxy-Canerenone from Biotransformation Broth
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作者 余彬 戴静 +6 位作者 张天真 黄达明 崔凤杰 孙文敬 王莉莉 钱静亚 张志才 《Agricultural Science & Technology》 CAS 2012年第12期2457-2460,共4页
[Objective] The aim was to investigate the effect of four extraction meth- ods on extraction ratio of 11-α-Hydroxy-Canerenone from biotransformation broth. [Method] Previous reported method, soaking, elution method a... [Objective] The aim was to investigate the effect of four extraction meth- ods on extraction ratio of 11-α-Hydroxy-Canerenone from biotransformation broth. [Method] Previous reported method, soaking, elution method and homogenate meth- ods were used. [Result] Results showed that more than 90% of the biotransformed 11-α-Hydroxy-Canerenone existed in the broth supernatant and mycelia surface. Elu- tion and soaking methods were effective for 11-α-Hydroxy-Canerenone extraction. Extraction yields of 96.0% and 98.8% were obtained by eluting with 400 ml of ethy- lacetate and soaking with ethylacetate for 90 min, respectively. [Conelusion] The method is simple and efficient, showing industrial application potential. 展开更多
关键词 11-α-Hydroxy-Canerenone EXTRACTION biotransformation
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Biotransformation of aesculin by human gut bacteria and identification of its metabolites in rat urine 被引量:5
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作者 Wei-Jun Ding Yun Deng +5 位作者 Hao Feng Wei-Wei Liu Rong Hu Xiang Li Zhe-Ming Gu Xiao-Ping Dong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第12期1518-1523,共6页
AIM: To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS: Representative human gut bacteria were collected from 20 he... AIM: To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS: Representative human gut bacteria were collected from 20 healthy volunteers, and then utilized in vitro to biotransform aesculin under anaerobic conditions. At 0, 2, 4, 8, 12, 16, 24, 48 and 72 h postincubation, 10 mL of culture medium was collected. Metabolites of aesculin were extracted 3 × from rat urine with methanol and analyzed by HPLC. For in vivo metabolite analysis, aesculetin (100 mg/kg) was administered to rats via stomach gavage, rat urine was collected from 6 to 48 h post-administration, and metabolite analysis was performed by LC/ESI-MS and MS/MS in the positive and negative modes.RESULTS: Human gut bacteria could completely convert aesculin into aesculetin in vitro. The biotransformation process occurred from 8 to 24 h post-incubation, with its highest activity was seen from 8 to 12 h. The in vitro process was much slower than the in vivo process. In contrast to the in vitro model, six aesculetin metabolites were identified in rat urine, including 6-hydroxy-7-glucocoumarin(M1), 6-hydroxy-7-sulf-coumarin (M2), 6, 7-digluco-coumarin (M3), 6-glc-7-gluco-coumarin (M4), 6-O-methyl-7-gluco-coumarin (MS) and 6-O-methyl-7- sulf-coumarin (M6). Of which, M2 and M6 were novel metabolites.CONCLUSION: Aesculin can be transferred into aesculetin by human gut bacteria and is further modified by the host in vivo. The diverse metabolites of aesculin may explain its pleiotropic pharmaceutical effects. 展开更多
关键词 Aesculin biotransformation Human gutbacteria Rat urine Sulfated derivatives LC/ESI-MS Aseculetin
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BIOTRANSFORMATION OF 2α,5α,10β,14β-TETRA-ACETOXY-4(20),11-TAXADIENE BY THE FUNGIJS CUNNINGHAMELLA ECHINULATA 被引量:3
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作者 Shang Hut HU Xu Fang TIAN Wei Hua ZHU and Qi Cheng FANG(Institute of Materia Medica, Chinese Academy or Medical Sciencesand Peking Union Medical College, Beijing 1000050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第6期543-544,共2页
?5α,10β,14β-Tetra-acctoxy-4(20).11-taxadicne (1) could be regioselectively transfonnedinto 6α 10β-dihydroxy-2α,5α,14β-triacetoxy-4(20). 11- taxadiene (2) by Cunninghamella echinnlata infair yield. 6βM.10β-Di... ?5α,10β,14β-Tetra-acctoxy-4(20).11-taxadicne (1) could be regioselectively transfonnedinto 6α 10β-dihydroxy-2α,5α,14β-triacetoxy-4(20). 11- taxadiene (2) by Cunninghamella echinnlata infair yield. 6βM.10β-Dihydroxy-2α,5α,14β-triacet 11-taxadienc (3). 10β-hydroxy-2α,5α,14β-triacetoxy-4(20).11-taxadiene (4), 10 β-hyboxy-4β,20-epoxy -2α,5α,14β-triacetoxy- tax - 11- ene (5)asminor prpducts were also isolated 展开更多
关键词 TETRA OF FUNGIJS THE CUNNINGHAMELLA ECHINULATA BY ACETOXY biotransformation
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Recent Progress on Biocatalysis and Biotransformations in Ionic Liquids 被引量:5
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作者 娄文勇 宗敏华 +1 位作者 吴虹 许若 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期543-549,共7页
Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liqu... Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions. 展开更多
关键词 ionic liquids biocatalysis and biotransformations enzymatic catalysis
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Biotransformation of 14-Deacetoxy-13-oxo sinenxan A by Ginkgo Cell Cultures 被引量:2
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作者 Jun Gui DAI Meng ZHANG +3 位作者 Min YE Wei Hua ZHU Ji Yu GUO Xiao Tian LIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第8期804-806,共3页
Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures ... Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures in 45% and 15% yields, respectively. 展开更多
关键词 biotransformation TAXANE cell suspension cultures Ginkgo biloba L.
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New polyhydroxylated metabolite derived from biotransformation of diosgenin by the white-rot fungus Coriolus versicolor 被引量:1
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作者 Wu, Guang Wei Li, Xiao Jun +2 位作者 Gao, Yi Jia, Yuan Gao, Jin Ming 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期446-448,共3页
Microbial transformation of diosgenin(1) was carried out with the white-rot fungus,Coriolus versicolor.A new polyhydroxyl metabolite,(25R)-spirost-5-ene-3β,7β,21-triol(2),was obtained as a result of hydroxylation.It... Microbial transformation of diosgenin(1) was carried out with the white-rot fungus,Coriolus versicolor.A new polyhydroxyl metabolite,(25R)-spirost-5-ene-3β,7β,21-triol(2),was obtained as a result of hydroxylation.Its structure was elucidated on the basis of 1D and 2D NMR as well as HR-ESI-MS spectroscopic analysis. 展开更多
关键词 (25R)-Spirost-5-ene-3β 21-triol Coriolus versicolor DIOSGENIN Microbial biotransformation BIOCATALYSIS
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Time-course monitoring of in vitro biotransformation reaction via solid-phase microextraction-ambient mass spectrometry approaches
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作者 Karol Jaroch Janusz Pawliszyn 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第1期186-191,共6页
The solid-phase microextraction technique quantifies analytes without considerably affecting the sample composition.Herein,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ion... The solid-phase microextraction technique quantifies analytes without considerably affecting the sample composition.Herein,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ionization(coated-PESI)and coated blade spray(CBS)as ambient mass spectrometry approaches for monitoring drug biotransformation.The ability of these methods was investigated for monitoring the dephosphorylation of a prodrug,combretastatin A4 phosphate(CA4P),into its active form,combretastatin A4(CA4),in a cell culture medium supplemented with fetal bovine serum.The CBS spot analysis was modified to achieve the same extraction efficiency as protein precipitation and obtained results in 7 min.Because coated-PESI performs extraction without consuming any samples,it is the preferred technique in the case of a limited sample volume.Although coated-PESI only extracts small quantities of analytes,it uses the desorption solvent volume of 5-10 pL,resulting in high sensitivity,thus allowing the detection of compounds after only 1 min of extraction.The biotransformation of CA4P into CA4 via phosphatases occurs within the simple matrix,and the proposed sample preparation techniques are suitable for monitoring the biotransformation. 展开更多
关键词 Solid-phase microextraction Coated probe electrospray ionization Coated blade spray COMBRETASTATIN biotransformation Prodrug activation
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Fatty acid hydratase for value-added biotransformation:A review
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作者 Yan Zhang Bekir Engin Eser +1 位作者 Peter Kristensen Zheng Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第8期2051-2063,共13页
The synthesis of hydroxy fatty acids(HFAs) from renewable oil feedstock by addition of water onto C_C bonds has attracted great attention in recent years. Given that selective asymmetric hydration of non-activated C_C... The synthesis of hydroxy fatty acids(HFAs) from renewable oil feedstock by addition of water onto C_C bonds has attracted great attention in recent years. Given that selective asymmetric hydration of non-activated C_C bonds has been proven difficult to achieve with chemical catalysts, enzymatic catalysis by fatty acid hydratases(FAHs) presents an attractive alternative approach to produce value-added HFAs with high regio-, enantioand stereospecificity, as well as excellent atom economy. Even though FAHs have just been investigated as a potential biocatalyst for a decade, remarkable information about FAHs in different aspects is available;however, a comprehensive review has not been archived. Herein, we summarize the research progresses on biochemical characterization, structural and mechanistic determination, enzyme engineering, as well as biotechnological application of FAHs. The current challenges and opportunities for an efficient utilization of FAHs in organic synthesis and industrial applications are critically discussed. 展开更多
关键词 Hydroxy fatty acids Fatty acid hydratases Enzyme characterization Catalytic mechanism Enzyme engineering biotransformation
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THE OVERLOOKED ECOSYSTEM DRIVING FORCE IN NON-EUTROPHICATED FRESHWATER SYSTEMS:DISSOLVED HUMIC SUBSTANCES-A SHORT REVIEW AND OUTLOOK
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作者 Christian E.W. Steinberg 《水生生物学报》 CAS CSCD 北大核心 2006年第6期721-733,共13页
This review starts with the description of the quantitative significance of dissolved organic material in general and dissolved humic substances (HS) in particular in various ecosystems. Despite their high quantities,... This review starts with the description of the quantitative significance of dissolved organic material in general and dissolved humic substances (HS) in particular in various ecosystems. Despite their high quantities, the knowledge about the role of HS is still very low and full of old, but still recycled paradigms. HS are thought to be inert or at least refractory and too large to be taken up by aquatic organisms. Instead, I present evidence that dissolved HS that mainly derives from the terrestrial environment, are taken up and directly and/or indirectly interfere with freshwater organisms and, thus, structure biocenoses. Relatively well known is in the meantime the fuelling function of allochthonous HS, which, upon irradiation, release fatty acids, which serve as substrates for microbial growth. This is an indirect effect of HS. Microbes, in turn, are food for mixotrophic algae and (heterotrophic) zooplankton. Thus, non-eutrophicated freshwaters are net-heterotrophic, meaning that respiration exceeds primary production. Furthermore, model calculations exemplify that only a very small portion of the terrestrial production is sufficient to cause net-heterotrophy in these freshwater bodies. But, recent papers show also that due to different stoichiometries the maximal plankton biomass production with algae or mixotrophs is higher than with bacteria. Very recently, several direct effects of HS have been elucidated. Among them are:induction of chaperons (stress shock proteins), induction and modulation of biotransformation enzymes, modulation (mainly inhibition) of photosynthetic oxygen release of aquatic plants, production of an internal oxidative stress, modulation of the offspring numbers in the nematode Caenorhabditis elegans[WTBZ], feminization of fish and amphibs, interference within the thyroid system, and action as chemical attractant to C. elegans. We are still in the phase of identifying the various physiological, biochemical, and molecular-biological effects. Hence, the ecological and ecophysiological significance of these HS-mediated effects still remain somewhat obscure. Nevertheless, HS appear generally to have an impact on the individual as well as on the community and even ecosystem level comparable to that of, for instance, nutrients. 展开更多
关键词 Humic substances Modulation of sex ratio Hormone-like effect Chemical attractant biotransformation Oxidative stress Direct effects of humic substances Indirect effects of humic substances Net-heterotrophy Forest stocking
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Biotransformation of Flavor Compositions During Fermentation of Litchi (Litchi Chinensis Sonn.) Fruits into Wine
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作者 Lu Yan Zeng Xia +1 位作者 Cao Jian-ping Luo Lan-ping 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第1期31-39,共9页
The aim was to examine the biotransformation of chemical compounds during the fermentation of litchi wine.S.bccyanus BV818 was inoculated to litchi juice(Heiye)to initiate the fermentation.Acetic acid decreased dramat... The aim was to examine the biotransformation of chemical compounds during the fermentation of litchi wine.S.bccyanus BV818 was inoculated to litchi juice(Heiye)to initiate the fermentation.Acetic acid decreased dramatically,succinic acid and DL-malic acid increased sharply.Saturated free fatty acid increased,especially the concentration of the free fatty acid with long carbon chain(more than 10 carbons)increased significantly.The unique flavor compounds of fresh litchi including linalool,α-terpineol,β-citronellol and other terpenoids remained in the litchi wine were transformed to other aroma constituents,by which the primary litchi flavor was retained.The wine had a fruity flavor and delicate bouquet and had harmonious sourness and sweetness.The litchi'Heiye'was suitable for being fermented into litchi wine. 展开更多
关键词 litchi wine FLAVOR FERMENTATION biotransformation
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Biotransformation of Carmoisine and Reactive Black 5 Dyes Using <i>Saccharomyces cerevisiae</i>
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作者 Abbas Sadeghi Mir Aboutaleb Kazemi Bazardehi +1 位作者 Shahrbanoo Raffe Batoul Zarif 《Health》 2014年第10期859-864,共6页
Saccharomyces cerevisiae (baker’s yeast) is the most important industrial microorganisms. This yeast is commonly used as a leavening agent in baking bread and bakery products, where it produces carbon dioxide from co... Saccharomyces cerevisiae (baker’s yeast) is the most important industrial microorganisms. This yeast is commonly used as a leavening agent in baking bread and bakery products, where it produces carbon dioxide from converting of the fermentable sugars present in the dough. Nowadays, industrial and chemical activities led to produce new compounds with new kinds of contamination in the environment. Discharge of untreated or partially treated industrial sewage has created the contamination problems of rivers and lakes such as drugs, oil, heavy metals, paints, pesticides and various chemical compounds in them. Hence, it is necessary to control and reduce the levels of these compounds in wastewater and bring them to permissible values. This study aims to study the bioconversion potential of commonly available Saccharomyces cerevisiae for the two textile dyes of Carmoisine and Reactive Black 5. Reaction mixtures for biotransformation of dyes included 50 mg/l Carmoisine or 25 mg/l Reactive Black 5 and 1% dried harvested cells of S. cerevisiae (bread’s yeast) were tested. Harvested dry and wet yeast were studied for this purpose. The results show that harvested cells of Saccharomyces cerevisiae are able to bioconvert Carmoisine and Reactive Black 5. Reactive Black 5, Carmoisine are degraded by biotransformation 85% and 53% within 24 hours in water at the room temperature. 展开更多
关键词 Saccharomyces cerevisiae Carmoisine REACTIVE BLACK 5 biotransformation DYES Decolourization
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Unbalanced biotransformation metabolism and oxidative stress status: implications for deficient fatty acid oxidation
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作者 Catharina M. Mels Francois H. Van der Westhuizen +1 位作者 Pieter J. Pretorius Elardus Erasmus 《Health》 2011年第1期43-48,共6页
The concept of accumulating xenobiotics within the human body as a health risk is well known. However, these compounds can also be endo-genous, as in the case of inborn errors of me-tabolism, and lead to some of the s... The concept of accumulating xenobiotics within the human body as a health risk is well known. However, these compounds can also be endo-genous, as in the case of inborn errors of me-tabolism, and lead to some of the same symp-toms as seen in xenobiotic intoxication. Bio-transformation of both exogenous and endo-genous toxic compounds is an important function of the liver, and the critical balance between these systems is of fundamental importance for cellular health. We propose a novel model, to describe the critical balance between Phase I and Phase II biotransformation and how a disturbance in this balance will increase the oxidative stress status, with resulting pathological consequences. We further used deficient fatty acid oxidation to verify the proposed model, as deficient fatty acid oxidation is associated with the accumulation of characteristic metabolites. These accumulating metabolites undergo both Phase I and Phase II biotransformation reactions, with resulting depletion of biotransformation substrates and co-factors. Depletion of these important biomolecules is capable of disturbing the balance between Phase I and Phase II reactions, and disturbance of this balance will increase oxidative stress status. The value of the proposed model is illustrated by its application to a clinical case investigated in our laboratory. In this case the possibility of deficient fatty acid oxidation only became evident once the critical balance between Phase I and Phase II biotransformation was restored with oral replenishment of biotransformation substrates. In addition to bio-chemical improvement, there was also significant clinical improvement. The significance of this model lies within the treatment possibilities, as the assessment of biotransformation metabolism and oxidative stress status can lead to the development of nutritional treatment strategies to correct imbalances. This in turn may reduce the chances of, or delay the onset of certain disease states. 展开更多
关键词 biotransformation METABOLISM DETOXIFICATION FATTY Acid Oxidation Oxidative Stress STATUS
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Biotransformation of 6-deoxypseudoanisatin by Synechocystis sp. PCC6803
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作者 Zhi Wang Xiaodong Cui +2 位作者 Chunmei Wang Jianmei Huang Di Geng 《Journal of Traditional Chinese Medical Sciences》 2014年第2期135-139,共5页
Objective:To explore the ability of Synechocystis sp.PCC6803 in transforming 6-deoxypseudoanisatin.Methods:The experiment was performed by incubating 6-deoxypseudoanisatin with the freshwater cyanobacterium Synechocys... Objective:To explore the ability of Synechocystis sp.PCC6803 in transforming 6-deoxypseudoanisatin.Methods:The experiment was performed by incubating 6-deoxypseudoanisatin with the freshwater cyanobacterium Synechocystis sp.PCC6803 under continuous white light at 30C for 5 days.The crude converted product was detected using thin-layer chromatography(TLC)and further analyzed using high-performance liquid chromatography(HPLC)as well as HPLC with electron spray ionization mass spectrometry(HPLC-ESI-MS).Results:TLC results showed that 6-deoxypseudoanisatin was converted into a less polar product.HPLC and MS data indicated that the retention time of the converted product increased in comparison with the standard of 6-deoxypseudoanisatin.Conclusion:Thus,the study appears to demonstrate that Synechocystis sp.PCC6803 can transform 6-deoxypseudoanisatin.The polarity of the converted product is less than that of 6-deoxypseudoanisatin. 展开更多
关键词 Synechocystis sp.PCC6803 6-deoxypseudoanisatin Seco-prezizaane-type sesquiterpene lactone biotransformation CYANOBACTERIUM
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Study on Biotransformation of Natural Anti-tumor Drug Podophyllotoxin
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作者 Baozhong SHI Lei ZHANG Duqiang LUO 《Agricultural Biotechnology》 CAS 2012年第3期29-31,34,共4页
[Objective] This study aimed to select stains for transforming podophyllotoxin, to isolate the transformation product and to identify the structure. [ Method~ Structure of podophyllotoxin was modified with microbial b... [Objective] This study aimed to select stains for transforming podophyllotoxin, to isolate the transformation product and to identify the structure. [ Method~ Structure of podophyllotoxin was modified with microbial batch transformation method. Podophyllotoxin and its transformation products were detected by using TLC and HPLC methods to select strains with ability to transform podophyllotoxin. Scale-up fermentation of one podophyllotoxin-transforming strain was carried out and the fermented material was extracted with EtoAc, isolated with conventional silica gel column chromatography, structure of the transformation product was identified by using classic spectroscopy technology. [ Result ] Based on researches of pedophyllotoxin transformation, seven strains with ability to transform po- dophyllotoxin were selected, including BS. Str-1, BS. Str-2, BS. Str-3, BS. Str-7, BS. Str-18, BS. Str-21 and BS. Str-29. By scale up fermentation, the only trans- formation product of BS. Str-21 strain was extracted and isolated, which was identified as picropodophyllotoxin. [ Conclusion] This study demonstrates that podo- phyllotoxin derivatives can be obtained by biotransformation methods, which lays the foundation for acquisition of natural drugs with high anti-tumor activity. 展开更多
关键词 ANTI-TUMOR Podophyllotoxin biotransformation
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