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Effect of β-Glucan (Angel Yeast) Compared to a Placebo on Cold and Flu Incidence and Symptoms in an Adult Population—A Double Blind, Randomised Controlled Trial
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作者 David Briskey Haibo Zhang +1 位作者 Zhixian Chen Amanda Rao 《Food and Nutrition Sciences》 CAS 2024年第6期484-497,共14页
Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at re... Background: 1-3, 1-6 β-glucan derived from Baker’s yeast (Saccharomyces cerevisiae) has been widely studied for its immune stimulatory capabilities and safety. Previous studies found β-glucan to have efficacy at reducing incidence of URTIs as well as being a low risk for negative side effects. The current study aimed to examine the effects of yeast β-glucan (Angel Yeast) on cold and flu incidences and symptoms in healthy adults. Methods: Two hundred and thirty-one males and females aged 18 to 65 years old supplemented with either β-glucan or a placebo for 3-months. Participants completed a general health questionnaire every 4 weeks and in addition, if participants experienced any cold or flu symptoms, these were recorded daily (along with severity) until resolved or up to 2 weeks. Results: Supplementation with β-glucan reduced the self-reported severity of sore throats and improved sleep quality compared to the placebo group. Conclusions: Yeast β-glucan supplementation appears to be able to help reduce certain symptoms experienced during a cold or flu episode and is safe and well tolerated. 展开更多
关键词 BETA-GLUCAN COLD FLU Baker’s yeast
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The setereoselective preparation ofβ-keto esters using baker's yeast in the presence of rice wine koji 被引量:4
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作者 Jin Cui Ming Jie Zhang Xiang Qian Wang Nai Jing Cui 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第3期311-313,共3页
By the addition of rice wine koji, enhancement of the reactivity was observed for the baker's yeast reduction of β-keto esters into (S)-β-hydroxy esters with high enantiomeric purity (73-98%).
关键词 Baker's yeast BIOCATALYsT Rice wine koji β-Keto esters
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Baker's Yeast Mediated Reduction of Optically Active Diketone 被引量:2
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作者 Xiao Lei GAO Gang ZHOU +2 位作者 Yu Kun GUAN Wei Dong LI Yu Lin LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第4期291-292,共2页
Baker's Yeast mediated reduction of optically active diketone has been described.
关键词 Baker’s yeast REDUCTION optically active DIKETONE
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Reaction Characteristics of Asymmetric Synthesis of (2S,5S)-2,5-Hexanediol Catalyzed with Baker’s Yeast Number 6 被引量:2
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作者 肖美添 叶静 +1 位作者 张亚武 黄雅燕 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期493-499,共7页
Baker’s yeast number 6 was selected by screening. It showed good catalytic activity and enantioselec-tivity for asymmetric reduction of 2,5-hexanedione to produce (2S,5S)-2,5-hexanediol. Gas chromatography-mass spect... Baker’s yeast number 6 was selected by screening. It showed good catalytic activity and enantioselec-tivity for asymmetric reduction of 2,5-hexanedione to produce (2S,5S)-2,5-hexanediol. Gas chromatography-mass spectrometry (GC-MS) revealed that the intermediate was (S)-5-hydroxyhexane-2-one. Reduction of 2,5-hexanedione proceeded in a two-step reaction. The hydroxyketone was initially formed, and this intermediate was further re-duced to the diol. Factors influencing the product yield and the enantiomeric excess of the reduction of 2,5-hexandione catalyzed by baker’s yeast number 6 were investigated. Higher concentration (≤100 mmol·L-1) of 2,5-hexandione did not influence 5-hydroxyhexane-2-one production, but 2,5-hexanediol production was inhibited by excess accumulation (>30 mmol·L-1) of intermediate. The optimal conditions were glucose as the co-substrate at an initial glucose concentration of 20 g·L-1, 34°C, pH 7.0 and cell concentration 60 g·L-1 (cell dry mass). Under the optimal condition and an initial substrate concentration of 30 mmol·L-1, the yield of 2,5-hexandiol was 78.7% and the enantiomeric excess of (2S,5S)-2,5-hexandiol was 94.4% for 24-h reduction. 展开更多
关键词 baker's yeast asymmetric reduetion (2s 5s)-2 5-hexanediol ENANTIOsELECTIVITY s)-5-hydroxyhexane-2-one
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A rapid absorbance-based growth assay to screen the toxicity of oligomer Aβ42 and protect against cell death in yeast 被引量:2
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作者 Prashant Bharadwaj Ralph Martins 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第10期1931-1936,共6页
Multiple lines of evidence show that soluble oligomer forms of amyloidβprotein(Aβ42)are the most neurotoxic species in the brain and correlates with the degree of neuronal loss and cognitive deficit in Alzheimer’s ... Multiple lines of evidence show that soluble oligomer forms of amyloidβprotein(Aβ42)are the most neurotoxic species in the brain and correlates with the degree of neuronal loss and cognitive deficit in Alzheimer’s disease.Although many studies have used mammalian cells to investigate oligomer Aβ42 toxicity,the use of more simple eukaryotic cellular systems offers advantages for large-scale screening studies.We have previously established and validated budding yeast,Saccharomyces cerevisiae to be a simple and a robust model to study the toxicity of Aβ.Using colony counting based methods,oligomeric Aβ42 was shown to induce dose-dependent cell death in yeast.We have adapted this method for high throughput screening by developing an absorbance-based growth assay.We further validated the assay with treatments previously shown to protect oligomer Aβ42 induced cell death in mammalian and yeast cells.This assay offers a platform for studying underlying mechanisms of oligomer Aβ42 induced cell death using gene deletion/overexpression libraries and developing novel agents that alleviate Aβ42 induced cell death. 展开更多
关键词 Alzheimer’s disease amyloid toxicity autophagy Aβ42 oligomer high-throughput screening latrepirdine NEUROPROTECTION yeast model
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Helicobacter is preserved in yeast vacuoles! Does Koch's postulates confirm it? 被引量:1
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作者 Nader Alipour Nasrin Gaeini 《World Journal of Gastroenterology》 SCIE CAS 2017年第12期2266-2268,共3页
The manuscript titled "Vacuoles of Candida yeast behave as a specialized niche for Helicobacter pylori(H.pylori)" not only has not been prepared in a scientific manner but the methodology used was not adequa... The manuscript titled "Vacuoles of Candida yeast behave as a specialized niche for Helicobacter pylori(H.pylori)" not only has not been prepared in a scientific manner but the methodology used was not adequate, and therefore the conclusion reached was not correct. First of all, "yeast" is a broad terminology covering a great number of genera and species of unicellular micro-organisms. The authors should have defined the organism with its binary scientific name. This measure would allow experiment reproduction by the scientific community. Moreover, the criteria established by Robert Koch to identify a specific microorganism or pathogen was not adopted in the methodology used. Regarding the methodology applied, use of the chicken eggyolk(Ig Y) antibody and PCR of the apparently tainted yeast population to prove H. pylori existence in the yeast vacuoles might be main factors for their wrong conclusions. Bacterial tropism toward yeast extract is a known phenomenon, and yeast extract is one of the main ingredients in culture media. Their internalization through phagocytosis or similar pathways does not seem possible or practical because of the thick and cellulosic yeast wall. While the small size of yeast cells does not support their ability in harboring several H. pylori, other observations such as inefficiency of antifungal therapy as anti-Helicobacter therapy strongly reject the conclusion reached by the above-mentioned article. 展开更多
关键词 Helicobacter pylori yeast Acanthamoeba castellanii Koch’s postulates
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Yeast One-hybrid System Used to Identify the Binding Proteins for Rat Glutathione S-transferase P Enhancer I 被引量:1
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作者 LiaoMX LiuDY 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第1期36-40,共5页
Objective To detect the trans-factors specifically binding to the strong enhancerelement (GPEI) in the upstream of rat glutathione S-transferase P (GST-P) gene. MethodsYeast one-hybrid system was used to screen rat... Objective To detect the trans-factors specifically binding to the strong enhancerelement (GPEI) in the upstream of rat glutathione S-transferase P (GST-P) gene. MethodsYeast one-hybrid system was used to screen rat lung MATCHMAKER cDNA library toidentify potential trans-factors that can interact with core sequence of GPEI(cGPEI).Electrophoresis mobility shift assay (EMSA) was used to analyze the binding of trans-factors to cGPEI. Results cDNA fragments coding for the C-terminal part of thetranscription factor c-Jun and rat adenine nucleotide translocator (ANT) were isolated. Thebinding of c-Jun and ANT to GPEI core sequence were confirmed. Conclusions Rat c-juntranscriptional factor and ANT may interact with cGPEI. They could play an important rolein the induced expression of GST-P gene. 展开更多
关键词 Glutathione s-transferase P enhancer I yeast one-hybrid system trans-actionfactor
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Transcriptional activation function of hepatitis B virus Pre S1 protein in yeast
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《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2003年第2期563-567,共5页
OBJECTIVE: To explore the feasibility of cloning of the hepatocyte receptor interacting with the Pre Slprotein of HBV by two-hybrid system.METHODS: Yeast expression plasmids encoding fusion proteins of full length or ... OBJECTIVE: To explore the feasibility of cloning of the hepatocyte receptor interacting with the Pre Slprotein of HBV by two-hybrid system.METHODS: Yeast expression plasmids encoding fusion proteins of full length or portions of Pre Sl ofHBV and DNA binding domain of yeast protein GAL4 were constructed and used to transform yeastreporter strain SFY526. Reporter gene product β-galactosidase activity was assayed as a measure oftranscriptional activation in yeast, Mammalian expression plasmid encoding fusion proteins of full lengthPre Sl and DNA binding domain of GAL4 was constructed and used to cotransfect hepatoma cell lineHuh-7 together with CAT reporter plasmid. Cell extracts were assayed for CAT activity by thin-layerchromatography.RESULTS: The fusion proteins of full length Pre Sl protein and GAL4 DNA binding domain presentedtranscriptional activation function in yeast. The transcription activating sequence was localized to the 21 to47 amino acids of Pre Sl protein. Fusion proteins of full length Pre Sl and GAL4 DNA binding domaindid not show transcriptional activation function in mammalian cells.CONCLUSIONS: The transcription activating sequence of HBV Pre Sl protein in yeast overlaps thehepatocyte receptor binding site. The transcriptional activation function of HBV Pre Sl protein in yeastmay prevent researchers from using yeast two-hybrid system to clone HBV receptor interacting with Pre Slprotein. However, the Pre Sl protein does not show transcriptional activation function in mammaliancells. Mammalian two-hybrid system may be a practical method to clone the HBV hepatocyte receptorinteracting with Pre Sl protein. 展开更多
关键词 HBV PRE s1 PROTEIN TRANsCRIPTIONAL ACTIVATION yeast
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Mec1-Dependent Phosphorylation of the Scc3 Subunit of Cohesin during Mitosis in Budding Yeast
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作者 Nathalie Grandin Michel Charbonneau 《Advances in Bioscience and Biotechnology》 2015年第3期153-163,共11页
Cohesin is an evolutionary conserved complex that controls chromosome segregation during mitosis. Here we show that, in response to DNA damage, Saccharomyces cerevisiae Scc3, one of the major regulatory subunits of th... Cohesin is an evolutionary conserved complex that controls chromosome segregation during mitosis. Here we show that, in response to DNA damage, Saccharomyces cerevisiae Scc3, one of the major regulatory subunits of the Smc1-Smc3-Scc1 cohesin ring, is phosphorylated on S/T-Q residues. This event depended on the Mec1 checkpoint kinase as well as on cell cycle arrest triggered by the DNA damage checkpoint network. This phosphorylation event also took place during mitosis of an unperturbed cell cycle. The present finding that S. cerevisiae Scc3 is phosphorylated during mitosis represents a potentially important new regulatory step in cohesin’s mitotic functions. 展开更多
关键词 COHEsIN s/T-Q PHOsPHORYLATION Mec1 and Tel1 DNA Damage Cell Cycle BUDDING yeast
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Effect of Feeding Different Levels of Dietary Protein and Addition of Baker's Yeast (Saccharomyces cerevisiae) on Productive Parameters of Awassi Lambs
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作者 Shaker Abdulameer Hassan Ali Ameen Saeed 《Journal of Agricultural Science and Technology(A)》 2013年第6期484-497,共14页
Forty eight individually fed Awassi male lambs were used in factorial experiment to investigate their responses to feeding concentrate diets containing three levels of dietary crude protein (CP), each was offered wi... Forty eight individually fed Awassi male lambs were used in factorial experiment to investigate their responses to feeding concentrate diets containing three levels of dietary crude protein (CP), each was offered without or with baker's yeast (SC) at rate of 0.5% (on dry matter (DM) basis). Concentrates were offered at rate of 3% of live body weight with free choice of barley straw. Results revealed that higher (P 〈 0.05) digestible dry matter (DDM) and digestible organic matter (DOM) intakes were achieved due to feeding medium level of CP and to the addition of SC. Addition of SC improved (P 〈 0.05) gain, lambs fed medium and high levels gained higher (P 〈 0.05) than those fed the low level of dietary CP. Feed conversion ratio (FCR) based on DM and organic matter (OM) intakes was not significantly affected by level of dietary CP or addition of yeast. Even though, less amount of N required per unit of gain was achieved with low and medium as compared to high levels. Higher DM, nitrogen free extract (NFE) and hemicellulose (P 〈 0.05), OM, CP, crude fiber (CF) and cellulose (P 〈 0.01) digestibilities were achieved in lambs fed the medium level of CP, whereas, no significant effect was observed on ether extract (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) digestibilities. Results also revealed that digestibility of almost all nutrients was improved with different extent due to addition of SC. Effect of interaction between levels of dietary CP and addition of SC referred to the preferability of addition of SC with medium level of dietary protein. 展开更多
关键词 PROTEIN baker's yeast growth DIGEsTIBILITY lambs.
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Isolation and Partial Evaluation of a Potential Indigenous Yeast Strain <i>Pichia kudriavzevii</i>from a Traditional Rice Beer—“Gora” Prepared by the Koloi Tribes of Tripura
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作者 Sushanta Ghosh Surajit De Mandal +4 位作者 Nandita Nath David L. Kaipeng Lovely Rahaman Senthil Kumar Nachimuthu Bipin Kumar Sharma 《Advances in Microbiology》 2019年第9期824-841,共18页
As per tradition from hundreds of years the Koloi tribes of Tripura are preparing “Gora”-therice based fermented beer which is very good in taste and aroma applying their traditional indigenous brewing techniques. I... As per tradition from hundreds of years the Koloi tribes of Tripura are preparing “Gora”-therice based fermented beer which is very good in taste and aroma applying their traditional indigenous brewing techniques. In this study, an attempt has been made to identify the indigenous yeast which is the main causative agent for fermentation and to investigate its fermentation ability with an industrial Saccharomyces cerevisiaes train. After investigation based on culture dependent phenotypic characteristics like-staining and biochemical characterization, primarily the responsible yeast species was determined as Pichia kudriavzevii and further confirmed followed by 18S rRNA ribotyping and the sequences was deposited at Gene bank and NCBI bearing specific accession number. In the comparative analysis, it has been found a significant similarities in all aspects of nutritional and alcohol percentages with the industrial strain in laboratory condition. The alcohol percentage in the rice beer “Gora” measured 6.40 ± 0.008% v/v. The study may be the first scientific investigation of its kind about this indigenous yeast strain isolated from “Gora” of this Indo-Burma biodiversity region and may provide sufficient background and potentiality for promoting these kinds of indigenous alcoholic beverages for small scale commercialization to strengthen the rural livelihood as well as to maintain immaterial cultural heritage. 展开更多
关键词 Beer yeast Fermentation 18s rRNA
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Efficacy of Xiaojin Capsules Combined with Selenium Yeast Capsules on 120 Cases of Hashimoto's Thyroiditis with Abnormal Thyroid Function
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作者 Zeyuan SHI Daoxin WANG +1 位作者 Jianxin HE Zijie SU 《Medicinal Plant》 CAS 2022年第5期88-91,共4页
[Objectives]To explore the efficacy of Xiaojin Capsules combined with Selenium Yeast Capsules in the treatment of Hashimoto's thyroiditis(HT)with abnormal thyroid function.[Methods]A total of 180 HT patients who w... [Objectives]To explore the efficacy of Xiaojin Capsules combined with Selenium Yeast Capsules in the treatment of Hashimoto's thyroiditis(HT)with abnormal thyroid function.[Methods]A total of 180 HT patients who were treated in the First Affiliated Hospital of Henan University and Henan Provincial People's Hospital from December 2020 to December 2021 were selected as the research subjects and randomly divided into the observation group(n=120)and the control group(n=60)in at a tratio of 2∶1 ratio according to their visiting time.The observation group was treated with Xiaojin Capsules(oral,5 capsules each time,twice a day for 12 weeks)and Selenium Yeast Capsules(oral,1 capsule each time,twice a day for 12 weeks).The control group was treated with only Selenium Yeast Capsules(oral,1 capsule each time,twice a day for 12 weeks).[Results]The difference in the levels of thyroid peroxidase antibody(TPO-Ab),thyroglobulin antibody(TGAb),serum free triiodothyronine(FT_(3)),serum free thyroxine(FT_(4)),and thyroid stimulating hormone(TSH)between the observation group and control group was statistically significant(P<0.05).The diameters of thyroid between the observation group and the control group before,during and after treatment were significantly different(P<0.05).The total effective rate of the observation group was 82.5%(99/120),which was significantly higher than 56.67%(34/60)in the control group,and the difference was statistically significant(P<0.05).The cure rate(22.50%)in the observation group was significantly higher than the control group(3.33%),and the difference was statistically significant(P<0.01).The ineffective rate of the observation group was 17.50%,which was significantly lower than that of the control group(40.00%),and the difference was statistically significant(P<0.01).The markedly effective rate of the observation group was 40.83%,which was significantly higher than that of the control group(31.67%),and the difference was statistically significant(P<0.05).The effective rate in the observation group was 191%,and the effective rate in the control group was 21.67%,and the difference was not statistically significant(P>0.05).[Conclusions]Xiaojin Capsules combined with Selenium Yeast Capsules in the treatment of HT can eliminate or alleviate the clinical symptoms and signs,significantly reduce the levels of TPO-Ab and TGAb in serum,restore thyroid function,improve thyroid shape and structure in the treatment of HT,and the clinical effect is satisfactory. 展开更多
关键词 Xiaojin Capsules selenium yeast Capsules Hashimoto’s thyroiditis Abnormal thyroid function Observation of efficacy
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Recovery of Residual Brewer’s Yeast by Electroactivation
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作者 Ruslan Tarna Elvira Vrabie +1 位作者 Irina Paladii Rodica Sturza 《Food and Nutrition Sciences》 2021年第12期1177-1190,共14页
Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and th... Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and the simultaneous obtaining of two products</span><span style="font-family:"">—<span>protein concentrates and hydrolyzed protein fr<span>om residual brewer’s yeast. Electroactivation is a non-residual process, wit</span>hout the use of chemical reagents and relatively inexpensive. The variation of the electroactivation conditions allowed the separation of 90% - 94% of the proteins in the form of protein concentrates. During the process, it is attested to increase the pH value and decrease the redox potential, which characterizes the multiple redox processes that take place in the cathode cell, including sedimentation at the isoelectric point. The presence of albumin in the protein fractions of RBY allows the formation of protein complexes with calcium, attributing a higher biological value to the obtained products. 展开更多
关键词 Brewer’s yeast Electroactivation Redox Potential Protein Concentrates Protein Hydrolysates CALCIUM
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Screening Yeasts from Ruminal Fluid of Dairy Heifer Fed a Different Ratio Roughage to Concentrate Diets
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作者 V. Sirisan V. Pattarajinda 《Journal of Agricultural Science and Technology(A)》 2011年第8期1155-1158,共4页
The objective of these studies were to identify ruminal yeast in varying ratios of roughage to concentrate in TMR diets in order to explore yeast diversity by using molecular technique with similarity of rDNA sequence... The objective of these studies were to identify ruminal yeast in varying ratios of roughage to concentrate in TMR diets in order to explore yeast diversity by using molecular technique with similarity of rDNA sequence. The experiment was assigned to four 98.6% of cross bred Holstein Friesian heifers with 2 levels and two replicates of roughage to concentrate ratios as: 10:90 (T1) and 50:50 (T2). The experimental period was 14 days. Rumen fluid sample was collected by stomach tube for total DNA extraction by using silica gel method, and analysis of quantity and quality of DNA by Nanovue and agarose gel electrophoresis. The divergent DI/D2 domain of 26S rDNA was amplified by primers NL-1(5'-GCA TAT CAA TAA GCG GAG GAA AAG-Y) and NL4 (5'-GGT CCG TGT TTCAAG ACG G-3') by polymerase chain reaction (PCR). The nucleotide sequences of D l/D2 domain of 26S rDNA were determined using PCR products. Generated sequences were aligned with related species by using the CLUSTAL W. The result showed that an average dry matter intake of TI was 7.00 kg/d and T2 was 6.99 kg/d. DNA concentrate from TIRI, TIR2, T2RI and T2R2 were 106, 131.5, 84 and 182.5 ng//aL, respectively. The purity of DNA was 1.57, 1.76, 1.78 and 1.86, respectively. The divergent D1/D2 domain of 26S rDNA of treatment could be amplified for T1R1 and T2R1 but could not for T1R2 and T2R2. The sequences of D1/D2 domain of 26S rDNA were compared with nucleotide database by BLAST programs (http://www.ncbi.nlrn.nih.gov/BLAST), the T2RI yeast-strain was closest to Yarrowia lipolytica. However, yeast strain in T1R1 could not be specifically identified because D 1/132 domain of 26S rDNA seem to represent variable region with number of nucleotide sequence showing 2-3 substitution from known species. The phylogenetic tree based on the sequences of the DI/D2 domain of 26S rDNA showed that TIR! was related to Pichia and Candida (96%) and T2R1 was related to Yarrowia lypolytica (100%). This study indicated that ruminal yeast strains could be found varying in different ratio of roughage to concentrate. 展开更多
关键词 Ruminal yeasts roughage level dairy heifer DI/D2 domain of 26s rDNA gene
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富铬酵母中14种元素的ICP-AES测定 被引量:7
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作者 丁文军 钱琴芳 +3 位作者 柴之芳 侯小琳 陈春英 丰伟悦 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 1999年第4期595-597,共3页
本文用ICP-AES法同时测定富铬酵母中K、Fe、P、Zn、Cr、Cu、Mn、Co、Ba、Sr、V、Na、Mg、Ca14种元素的含量。结果表明,富铬酵母中的铬对其他元素的浓度有一定影响,并且,K、Mn、P、V、Mg、... 本文用ICP-AES法同时测定富铬酵母中K、Fe、P、Zn、Cr、Cu、Mn、Co、Ba、Sr、V、Na、Mg、Ca14种元素的含量。结果表明,富铬酵母中的铬对其他元素的浓度有一定影响,并且,K、Mn、P、V、Mg、Ca的浓度明显低于普通酵母。 展开更多
关键词 ICP AEs 富铬酵母 微量元素 测定 补铬制剂
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pH对S-腺苷-L-蛋氨酸发酵的影响 被引量:6
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作者 王昌禄 朱汉春 +3 位作者 张晓霞 周庆礼 陈勉华 陈俊伟 《生物技术通报》 CAS CSCD 2007年第6期154-156,161,共4页
研究了不同pH控制方式对S-腺苷-L-蛋氨酸(SAM)发酵过程及产量的影响。通过对发酵过程中不控制pH、控制恒定pH、两阶段控制pH和三阶段控制pH实验,研究了不同条件下对菌体干重、葡萄糖代谢和SAM产量的影响。控制合适的pH有利于菌体生长与... 研究了不同pH控制方式对S-腺苷-L-蛋氨酸(SAM)发酵过程及产量的影响。通过对发酵过程中不控制pH、控制恒定pH、两阶段控制pH和三阶段控制pH实验,研究了不同条件下对菌体干重、葡萄糖代谢和SAM产量的影响。控制合适的pH有利于菌体生长与SAM的生物合成,菌体生长最适pH为6.0,SAM转化最适pH为6.5,采用三阶段控制pH,使SAM产量比不控制pH提高了133%,比控制pH6.5提高了18.6%,比两阶段控制pH提高了10%。 展开更多
关键词 PH s-腺苷-L-蛋氨酸 发酵 酵母
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固定化酵母不对称水解布洛芬乙酯制备S(+)-布洛芬 被引量:4
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作者 赵国骏 吉鑫松 +2 位作者 钱雪明 姜涌明 袁中一 《药物生物技术》 CAS CSCD 1996年第4期214-217,共4页
用多种固定化载体对含有不对称水解布洛芬酯的脂肪酶的丝孢酵母进行固定化。海藻酸钙、卡拉胶、聚丙烯酰胺凝胶和PVA固定化酵母后,酶活力回收分别为6%、16%、18%和7%;用自制的高脱乙酰度、高分子量的壳聚糖,通过成囊装... 用多种固定化载体对含有不对称水解布洛芬酯的脂肪酶的丝孢酵母进行固定化。海藻酸钙、卡拉胶、聚丙烯酰胺凝胶和PVA固定化酵母后,酶活力回收分别为6%、16%、18%和7%;用自制的高脱乙酰度、高分子量的壳聚糖,通过成囊装置包埋酵母细胞,并用戊二醛交联,制得直径1.0mm左右的固定化酵母细胞壳聚糖多孔微球,酶活力回收达80%以上,操作半衰期75天以上,而且每次反应所产生的布洛芬的比旋光度均为[α]20D=+55°左右。固定化酶的最适温度从未固定化时的35℃提高到45℃。每克干重的壳聚糖可固定化1~5倍干重的酵母,固定化壳聚糖微球有较高机械强度。 展开更多
关键词 布洛芬 酵母细胞 固定化 壳聚糖微球 水解
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发酵生产S-腺苷-L-蛋氨酸培养条件的优化研究 被引量:15
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作者 董函竹 刘沛溢 谭天伟 《微生物学通报》 CAS CSCD 北大核心 2006年第1期110-113,共4页
考察了摇瓶发酵生产S-腺苷-L-蛋氨酸过程中碳源、氮源、无机盐和生长因子以及培养过程中补加L-蛋氨酸时间对S-腺苷-L-蛋氨酸的产量、含量及生物量的影响。并通过均匀实验设计对培养基配方进行优化,在30℃、180 r/m in的培养条件下,得到... 考察了摇瓶发酵生产S-腺苷-L-蛋氨酸过程中碳源、氮源、无机盐和生长因子以及培养过程中补加L-蛋氨酸时间对S-腺苷-L-蛋氨酸的产量、含量及生物量的影响。并通过均匀实验设计对培养基配方进行优化,在30℃、180 r/m in的培养条件下,得到最后的培养基配方为:葡萄糖30g,酵母粉11g,(NH4)2SO412g,K2HPO4.3H2O 5g,KH2PO410g,MnSO4.H2O 0.09g,ZnSO4.7H2O 0.14g,MgC l20.5g,CaC l20.3g,CuSO40.005g,自来水定容至1L。摇瓶中优化后的S-腺苷-L-蛋氨酸产量可以达到0.9g/L,比优化前产量提高了30%。采用优化后的培养基和培养条件在5L发酵罐中间歇培养,24h后一次性补加24g/L葡萄糖和1.0g/L L-蛋氨酸,继续培养24h后产量可达2.66g/L,生物量23.4g/L。 展开更多
关键词 发酵 s-腙苷-L-蛋氨酸 酵母 均匀设计
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酵母静息细胞催化丙酮酸乙酯不对称还原制(S)-乳酸乙酯 被引量:8
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作者 王丹 张强 +4 位作者 李旺 戚南昌 郭春晓 杨志荣 张杰 《催化学报》 SCIE EI CAS CSCD 北大核心 2011年第6期1035-1039,共5页
从污水处理池及其附近土壤中分离到36株可将丙酮酸乙酯不对称还原成(S)-乳酸乙酯的菌株,经多次复筛,最终得到一株具有较高催化活性的酵母菌BTY18-6.以BTY18-6的静息细胞为催化剂,在水相中进行丙酮酸乙酯不对称还原成(S)-乳酸乙酯的反应... 从污水处理池及其附近土壤中分离到36株可将丙酮酸乙酯不对称还原成(S)-乳酸乙酯的菌株,经多次复筛,最终得到一株具有较高催化活性的酵母菌BTY18-6.以BTY18-6的静息细胞为催化剂,在水相中进行丙酮酸乙酯不对称还原成(S)-乳酸乙酯的反应,并对反应条件进行了优化.结果表明,以2.5%葡萄糖为辅助底物,反应体系初始pH=6.8,发酵培养48h的菌体湿度0.175g/ml,丙酮酸乙酯初始浓度65mmol/L,于32oC反应48h的条件下,丙酮酸乙酯转化率达95.5%,产物对映体过量值(ee值)为92.1%. 展开更多
关键词 酵母静息细胞 生物催化 丙酮酸乙酯 不对称还原 (s)-乳酸乙酯
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S-腺苷-L-蛋氨酸的分离纯化及其稳定产品的制备 被引量:8
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作者 刘惠 吴坚平 +1 位作者 林建平 岑沛霖 《中国生化药物杂志》 CAS CSCD 2002年第6期284-287,共4页
目的 从酵母萃取液中分离纯化S-腺苷-L-蛋氨酸(SAM)并制备其稳定的盐产品。方法 以苦味酸作为选择性沉淀剂,结合有机溶剂结晶方法沉淀SAM盐产品。结果 确定了影响各步得率的关键因素和最适条件。结论 硫酸盐的制备得率(从酵母到成品)可... 目的 从酵母萃取液中分离纯化S-腺苷-L-蛋氨酸(SAM)并制备其稳定的盐产品。方法 以苦味酸作为选择性沉淀剂,结合有机溶剂结晶方法沉淀SAM盐产品。结果 确定了影响各步得率的关键因素和最适条件。结论 硫酸盐的制备得率(从酵母到成品)可达60%以上,而硫酸、对甲苯磺酸双盐的得率可达50%以上。 展开更多
关键词 s—腺苷—L—蛋氨酸 分离 纯化 盐产品 制备
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