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Effects of dietary Clostridium butyricum and rumen protected fat on meat quality,oxidative stability,and chemical composition of finishing goats
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作者 Meimei Zhang Zhiyue Zhang +9 位作者 Xinlong Zhang Changming Lu Wenzhu Yang Xiaolai Xie Hangshu Xin Xiaotan Lu Mingbo Ni Xinyue Yang Xiaoyang Lv Peixin Jiao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期911-924,共14页
Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide ... Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle. 展开更多
关键词 Chemical composition clostridium butyricum Goats Meat quality Oxidative stability Rumen protected fat
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Supplemental Clostridium butyricum modulates lipid metabolism by reshaping the gut microbiota composition and bile acid profile in IUGR suckling piglets
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作者 Xin Zhang Yang Yun +7 位作者 Zheng Lai Shuli Ji Ge Yu Zechen Xie Hao Zhang Xiang Zhong Tian Wang Lili Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1150-1166,共17页
Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,... Background Intrauterine growth restriction(IUGR)can cause lipid disorders in infants and have long-term adverse effects on their growth and development.Clostridium butyricum(C.butyricum),a kind of emerging probiotics,has been reported to effectively attenuate lipid metabolism dysfunctions.Therefore,the objective of this study was to investigate the effects of C.butyricum supplementation on hepatic lipid disorders in IUGR suckling piglets.Methods Sixteen IUGR and eight normal birth weight(NBW)neonatal male piglets were used in this study.From d 3to d 24,in addition to drinking milk,the eight NBW piglets(NBW-CON group,n=8)and eight IUGR piglets(IUGR-CON group,n=8)were given 10 mL sterile saline once a day,while the remaining IUGR piglets(IUGR-CB group,n=8)were orally administered C.butyricum at a dose of 2×108colony-forming units(CFU)/kg body weight(suspended in 10 mL sterile saline)at the same frequency.Results The IUGR-CON piglets exhibited restricted growth,impaired hepatic morphology,disordered lipid metabolism,increased abundance of opportunistic pathogens and altered ileum and liver bile acid(BA)profiles.However,C.butyricum supplementation reshaped the gut microbiota of the IUGR-CB piglets,characterized by a decreased abundance of opportunistic pathogens in the ileum,including Streptococcus and Enterococcus.The decrease in these bile salt hydrolase(BSH)-producing microbes increased the content of conjugated BAs,which could be transported to the liver and function as signaling molecules to activate liver X receptorα(LXRα)and farnesoid X receptor(FXR).This activation effectively accelerated the synthesis and oxidation of fatty acids and down-regulated the total cholesterol level by decreasing the synthesis and promoting the efflux of cholesterol.As a result,the growth performance and morphological structure of the liver improved in the IUGR piglets.Conclusion These results indicate that C.butyricum supplementation in IUGR suckling piglets could decrease the abundance of BSH-producing microbes(Streptococcus and Enterococcus).This decrease altered the ileum and liver BA profiles and consequently activated the expression of hepatic LXRαand FXR.The activation of these two signaling molecules could effectively normalize the lipid metabolism and improve the growth performance of IUGR suckling piglets. 展开更多
关键词 Bile acid clostridium butyricum Gut microbiota Intrauterine growth restriction Lipid metabolism Suckling piglet
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Efficient reduction ofβ-lactoglobulin allergenicity in milk using Clostridium tyrobutyricum Z816
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作者 Qianru Zhao Yuwei Wang +3 位作者 Zhengming Zhu Quanyu Zhao Liying Zhu Ling Jiang 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期809-816,共8页
Milk allergy is one of the most common food allergies,affecting 6%of young children,andβ-lactoglobulin(β-LG)is the main milk allergen.Clostridium tyrobutyricum Z816 was selected for the degradation ofβ-LG,which was... Milk allergy is one of the most common food allergies,affecting 6%of young children,andβ-lactoglobulin(β-LG)is the main milk allergen.Clostridium tyrobutyricum Z816 was selected for the degradation ofβ-LG,which was successfully reduced by about 90%using permeabilized bacteria under the optimized conditions.The hydrolyzed peptides were identified by liquid chromatography-tandem mass spectrometry(LC-MS/MS)and analyzed by molecular modeling,which indicated that C.tyrobutyricum Z816 could effectively degrade the antigenic epitopes ofβ-LG.Finally,the concentration and digestibility ofβ-LG in actual samples was quantified using enzyme-linked immunosorbent assay(ELISA)and gastrointestinal digestion simulation experiments.The results showed more than 92%ofβ-LG in actual samples was hydrolyzed,and the gastric and total digestibility of whey protein isolate(WPI)was improved by 85.96%and 64.51%,respectively.Therefore,C.tyrobutyricum Z816 offers an effective method to degradeβ-LG and reduce the occurrence of milk allergies,which has great significance for the development of hypoallergenic dairy products. 展开更多
关键词 Milk allergy Β-LACTOGLOBULIN clostridium tyrobutyricum Permeabilized bacteria
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Clostridium perfringens gas gangrene caused by closed abdominal injury: A case report and review of the literature
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作者 He-Yun Li Zhi-Xiang Wang +1 位作者 Jian-Chun Wang Xiao-Di Zhang 《World Journal of Clinical Cases》 SCIE 2023年第4期852-858,共7页
BACKGROUND Abdominal Clostridium perfringens(C. perfringens) gas gangrene is a rare infection that has been described in the literature as most frequently occurring in postoperative patients with open trauma. Intra-ab... BACKGROUND Abdominal Clostridium perfringens(C. perfringens) gas gangrene is a rare infection that has been described in the literature as most frequently occurring in postoperative patients with open trauma. Intra-abdominal gas gangrene caused by C.perfringens infection after closed abdominal injury is extremely rare, difficult to diagnose, and progresses rapidly with high mortality risk. Here, we report a case of C. perfringens infection caused by closed abdominal injury.CASE SUMMARY A 54-year-old male suffered multiple intestinal tears and necrosis after sustaining an injury caused by falling from a high height. These injuries and the subsequent necrosis resulted in intra-abdominal C. perfringens infection. In the first operation,we removed the necrotic intestinal segment, kept the abdomen open and covered the intestine with a Bogota bag. A vacuum sealing drainage system was used to cover the outer layer of the Bogota bag, and the drainage was flushed under negative pressure. The patient was transferred to the intensive care unit for supportive care and empirical antibiotic treatment. The antibiotics were not changed until the results of bacterial culture and drug susceptibility testing were obtained.Two consecutive operations were then performed due to secondary intestinal necrosis. After three definitive operations, the patient successfully survived the perioperative period. Unfortunately, he died of complications related to GuillainBarre syndrome 75 d after the first surgery. This paper presents this case of intraabdominal gas gangrene infection and analyzes the diagnosis and treatment based on a review of current literature.CONCLUSION When the intestines rupture leading to contamination of the abdominal cavity by intestinal contents, C. perfringens bacteria normally present in the intestinal tract may proliferate in large numbers and lead to intra-abdominal infection. Prompt surgical intervention, adequate drainage,appropriate antibiotic therapy, and intensive supportive care comprise the most effective treatment strategy. If the abdominal cavity is heavily contaminated, an open abdominal approach may be a beneficial treatment. 展开更多
关键词 clostridium perfringens Intra-abdominal infection Gas gangrene Open abdomen Case report
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Detection, Biochemical and Molecular Characterization of Clostridium sporogens in Nono: A Nigerian Traditionally Fermented Yoghurt Drink
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作者 Nofisat Olaide Oyedokun Gbadebo Barnabas Olukotun +4 位作者 Uchenna Iman Igwegbe Binta Buba Adamu Roseline Rumi Ideh Olaitan Comfort Shekoni Amin Oderaa Igwegbe 《Open Journal of Medical Microbiology》 CAS 2023年第1期91-100,共10页
Nono is a traditionally fermented milk drink commonly consumed in the Northern parts of Nigeria. It is produced through the spontaneous fermentation of raw cow milk by Lactic Acid Bacteria (LAB), a process that could ... Nono is a traditionally fermented milk drink commonly consumed in the Northern parts of Nigeria. It is produced through the spontaneous fermentation of raw cow milk by Lactic Acid Bacteria (LAB), a process that could result to the contamination of the product with such pathogenic organisms as Clostridia spp. The aim of this research was therefore to determine the incidence of Clostridia species in thirty-two (32) ready-to-drink nono samples collected directly from a number of Fulani vendors in randomly selected locations within the Federal Capital Territory (FCT), Abuja, Nigeria. Isolated organisms were further subjected to some morphological and biochemical characterizations using standard microbiological procedures. The results obtained indicate that fourteen (14) isolates were putatively identified to be Clostridium sp., out of which five (5) isolates were confirmed to be Clostridium sporogens by a BLAST analysis of their respective 16SrRNA nucleotide sequence. It was concluded that, the detection of these pathogenic strains in frequently consumed product like nono could pose a public health risk and proactive measures to prevent an outbreak of food borne illness from nono consumption, were recommended. 展开更多
关键词 Fermentation Nono clostridium sporogens PATHOGENIC Food Borne Illness
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响应面法优化Clostridium beijerinckii木糖发酵产丁醇培养基的研究 被引量:10
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作者 刘娅 刘宏娟 +1 位作者 张建安 陈宗道 《食品工业科技》 CAS CSCD 北大核心 2010年第7期194-196,共3页
采用响应面法对Clostridium beijerinckii利用木糖发酵生产丁醇的培养基进行了优化,建立了回归方程,得到了Cl·beijerinckii木糖发酵的优化培养基组成为:木糖26·6g/L,酵母浸粉1·38g/L,维生素液5·55mL/L,微量元素液9&... 采用响应面法对Clostridium beijerinckii利用木糖发酵生产丁醇的培养基进行了优化,建立了回归方程,得到了Cl·beijerinckii木糖发酵的优化培养基组成为:木糖26·6g/L,酵母浸粉1·38g/L,维生素液5·55mL/L,微量元素液9·67mL/L。在此优化条件下发酵,丁醇产量提高了18·4%,达到6·69g/L。 展开更多
关键词 clostridium beijerinckii 木糖 丁醇 培养基 响应面法
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Clostridium saccharobutylicum利用玉米秸秆水解液发酵生产燃料丁醇 被引量:7
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作者 王云 倪晔 +2 位作者 孙志浩 宋刚 夏子义 《食品与生物技术学报》 CAS CSCD 北大核心 2012年第9期904-911,共8页
以Clostridium saccharobutylicum DSM 13864为丁醇生产菌株,采用正交优化法确定了以玉米秸秆水解液为底物的最优培养基配方:CaCO32.0 g/L,(NH4)2SO41.0 g/L,K2HPO40.5 g/L,玉米浆干粉15 g/L,MnSO4.H2O 0.01 g/L。采用该最优培养基配方,... 以Clostridium saccharobutylicum DSM 13864为丁醇生产菌株,采用正交优化法确定了以玉米秸秆水解液为底物的最优培养基配方:CaCO32.0 g/L,(NH4)2SO41.0 g/L,K2HPO40.5 g/L,玉米浆干粉15 g/L,MnSO4.H2O 0.01 g/L。采用该最优培养基配方,在3 L发酵罐中发酵培养40 h后,总溶剂为16.1 g/L,其中丁醇10.59 g/L,发酵强度为0.40 g/(L·h),生产率为0.33 g/g。通过对发酵过程进行变温调控证实低温有利于溶剂积累,总溶剂由17.01 g/L提高至19.98 g/L。在稀释率为0.1 h-1的变温连续发酵过程中,从80 h开始进入稳定产溶剂状态并持续至269 h,该阶段平均总溶剂为12.28 g/L(其中丁醇8.50 g/L),发酵强度为1.23 g/(L·h),是变温分批发酵(D方式)的4.92倍。 展开更多
关键词 clostridium saccharobutylicum 玉米秸秆水解液 丁醇 变温连续发酵
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基于比较基因组学的Clostridium kluyveri己酸代谢途径关键酶生物信息学分析 被引量:2
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作者 徐友强 孙宝国 +8 位作者 蒋玥凤 鹿发展 张成楠 邹伟 王文华 杨然 滕超 范光森 李秀婷 《食品科学》 EI CAS CSCD 北大核心 2019年第4期122-129,共8页
对3株白酒来源重要的己酸生产菌株Clostridium kluyveri(NBRC 12016、JZZ和DSM 555)全基因组信息进行比较基因组学分析,聚焦于己酸代谢途径核心催化酶,发现NBRC 12016的己酸代谢途径未得到有效注释,JZZ的己酸代谢途径核心催化酶酰基辅酶... 对3株白酒来源重要的己酸生产菌株Clostridium kluyveri(NBRC 12016、JZZ和DSM 555)全基因组信息进行比较基因组学分析,聚焦于己酸代谢途径核心催化酶,发现NBRC 12016的己酸代谢途径未得到有效注释,JZZ的己酸代谢途径核心催化酶酰基辅酶A脱氢酶存在注释错误。进一步对C. kluyveri模式菌株DSM 555己酸代谢途径的关键酶硫解酶ThlA进行生物信息学分析,发现DSM 555携带3拷贝的ThlA,且具有序列多态性,可能与催化脂肪酸代谢链延长的底物特异性相关。结构分析和分子对接表明,硫解酶Thl A1的底物催化属于氧化还原开关调控机制,并预测了酶的关键催化位点和具体的催化过程。上述分析结果有助于为后续进一步改进菌株的己酸生产性能和更好地应用于白酒酿造提供依据。 展开更多
关键词 白酒 clostridium kluyveri 己酸 代谢途径 硫解酶 比较基因组学
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产氢菌Clostridium butyricum P22的分离鉴定及其产氢特性研究 被引量:3
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作者 潘春梅 张晓静 樊耀亭 《环境科学与技术》 CAS CSCD 北大核心 2011年第8期9-13,17,共6页
从连续生物制氢反应器中分离得到高效产氢细菌P22,利用微生物自动鉴定仪并结合菌株16S rDNA序列分析,将其鉴定为Clostridium butyricum P22。同时还进一步研究了碳源、氮源、初始pH值和培养温度对菌株P22产氢活性的影响。结果表明:该菌... 从连续生物制氢反应器中分离得到高效产氢细菌P22,利用微生物自动鉴定仪并结合菌株16S rDNA序列分析,将其鉴定为Clostridium butyricum P22。同时还进一步研究了碳源、氮源、初始pH值和培养温度对菌株P22产氢活性的影响。结果表明:该菌株能利用多种碳源氮源产氢,当以葡萄糖作为产氢底物时,其最大产氢量和产氢速率分别为为301.7 mL/g-glucose(2.42 mol/mol-glucose)、31.1 mL(/g-glucose.h)。发酵液的初始pH和培养温度严重影响产氢菌活性,初始pH6.47、35℃培养为该菌种较为适宜的产氢条件。利用Arrehnius方程以葡萄糖为底物拟合得到该菌株产氢反应的活化能为70.7 kcal/mol。经能量分析,Clostridium butyricum P22产氢过程中葡萄糖能量回收率为20.6%。该菌株在生物制氢中具有很好的应用发展前景。 展开更多
关键词 生物制氢 clostridium butyricum 分离鉴定 产氢特性
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Clostridium autoethanogenum的生长培养基优化 被引量:2
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作者 郭颖 许敬亮 +1 位作者 徐惠娟 袁振宏 《可再生能源》 CAS 北大核心 2011年第1期53-56,共4页
Clostridium autoethanogenum是一种能将H2,CO以及CO2转变成乙醇和乙酸的特殊菌株。文章采用数值方法对C.autoethanogenum的生长培养基进行了优化。首先,用Plackett-Burman设计筛选出酵母膏是唯一影响C.autoethanogenum的显著因素,并得... Clostridium autoethanogenum是一种能将H2,CO以及CO2转变成乙醇和乙酸的特殊菌株。文章采用数值方法对C.autoethanogenum的生长培养基进行了优化。首先,用Plackett-Burman设计筛选出酵母膏是唯一影响C.autoethanogenum的显著因素,并得到11种组分的相对较优浓度。然后,用梯度试验进一步确定酵母膏的最佳浓度为1.5 g/L,从而最终确立改良的培养基配方。在试验条件下,优化的培养基能得到399.46 mg/L C.au-toethanogenum。此优化培养基能应用于两步CSTRs发酵合成气制乙醇。 展开更多
关键词 clostridium autoethanogenum PLACKETT-BURMAN设计 合成气发酵 培养基优化
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低温蛋白酶产生菌Clostridium bifermentans B-25发酵条件优化 被引量:2
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作者 崔冠慧 程辉彩 +2 位作者 张丽萍 习彦花 张根伟 《江苏农业科学》 CSCD 北大核心 2012年第7期335-337,共3页
为提高低温蛋白酶产生菌Clostridium bifermentans B-25的产酶活性,通过单因子和正交试验,对其培养条件进行了优化。结果表明,其最佳培养基组成为酵母粉20.0 g/L、蛋白胨20.0 g/L、淀粉10.0 g/L、MgSO4 0.4 g/L、KH2PO40.2 g/L。最适培... 为提高低温蛋白酶产生菌Clostridium bifermentans B-25的产酶活性,通过单因子和正交试验,对其培养条件进行了优化。结果表明,其最佳培养基组成为酵母粉20.0 g/L、蛋白胨20.0 g/L、淀粉10.0 g/L、MgSO4 0.4 g/L、KH2PO40.2 g/L。最适培养条件为pH值7.5,最适温度16~30℃,最佳培养时间72 h。在最适培养条件下,采用优化培养基,低温蛋白酶产生菌B-25产酶活性达43.8 U/mL。 展开更多
关键词 低温蛋白酶 clostridium bifermentans B-25 发酵条件
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Clostridium papyrosolvens厌氧发酵产氢研究
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作者 靳孝庆 徐昊 +1 位作者 沈磊 何冰芳 《应用与环境生物学报》 CAS CSCD 北大核心 2008年第1期104-107,共4页
采用分批培养研究了从高浓度厌氧产氢活性污泥中筛选的优势菌种Clostridium papyrosolvens的发酵产氢能力.结果表明:该菌有较强的高糖耐受性和耐酸性,当葡萄糖浓度为30g/L、pH阶段性控制在4.5时,发酵44h葡萄糖消耗率为83.7%,总产气量达... 采用分批培养研究了从高浓度厌氧产氢活性污泥中筛选的优势菌种Clostridium papyrosolvens的发酵产氢能力.结果表明:该菌有较强的高糖耐受性和耐酸性,当葡萄糖浓度为30g/L、pH阶段性控制在4.5时,发酵44h葡萄糖消耗率为83.7%,总产气量达到3081.3mL/L,最高产气率为187.5mLL-1h-1,氢气含量为67.5%,比产氢率达1.06mol(H2)/mol(葡萄糖).研究中选用了廉价的发酵产氢培养基,以玉米浆为氮源,以还原铁粉作氧化还原电位控制剂,省去了牛肉膏、蛋白胨等昂贵氮源以及L-半胱氨酸、维生素、无机离子等高成本组分,显著降低了纯菌发酵的培养基成本,获得了较好的产氢效果. 展开更多
关键词 clostridium papyrosolvens 厌氧发酵 产氢 葡萄糖
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肿瘤治疗中Clostridium novyi-NT的研究
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作者 石新丽 张硕 +1 位作者 丁娜娜 李明远 《肿瘤防治研究》 CAS CSCD 北大核心 2015年第1期74-77,共4页
联合细菌的溶瘤治疗(combined bacteriolytic therapy,COBALT)策略在实体瘤治疗中方兴未艾。此策略是将专性厌氧菌Clostridium novyi-NT联合传统放化疗药物治疗实体瘤,现处于临床Ⅰ期试验阶段。本文分别从有效性及安全性等方面总结了抗... 联合细菌的溶瘤治疗(combined bacteriolytic therapy,COBALT)策略在实体瘤治疗中方兴未艾。此策略是将专性厌氧菌Clostridium novyi-NT联合传统放化疗药物治疗实体瘤,现处于临床Ⅰ期试验阶段。本文分别从有效性及安全性等方面总结了抗肿瘤细菌应具有的标准,并简述了C.novyi-NT的溶瘤机制。 展开更多
关键词 肿瘤治疗 clostridium novyi-NT 溶瘤细菌
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Clostridium difficile的中文翻译商讨 被引量:1
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作者 方忠宏 《抗感染药学》 2009年第3期222-222,共1页
"艰难梭菌"是近几年来备受关注的专业词。但是,在大量资料上也有"难辨梭菌"一词,其使用频率似乎更高。两者均无英文对照,谈及内容极相似。原来两者均是Clostridium difficile的译名。
关键词 艰难梭菌 难辨梭菌 clostridium DIFFICILE 抗菌药物 译名
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利用Clostridium saccharobutylicum DSM 13864连续发酵生产丁醇 被引量:8
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作者 夏子义 倪晔 +2 位作者 孙志浩 王云 吴香玉 《化工进展》 EI CAS CSCD 北大核心 2013年第1期156-160,173,共6页
为使用廉价糖质原料进行连续发酵生产丁醇提供理论依据和实验指导,以Clostridium saccharobutylicumDSM 13864为发酵菌种,考察了稀释率和温度等因素对以葡萄糖为原料的四级连续发酵生产丁醇的影响。结果表明:高稀释率有利于酸的积累和... 为使用廉价糖质原料进行连续发酵生产丁醇提供理论依据和实验指导,以Clostridium saccharobutylicumDSM 13864为发酵菌种,考察了稀释率和温度等因素对以葡萄糖为原料的四级连续发酵生产丁醇的影响。结果表明:高稀释率有利于酸的积累和菌体的生长,低稀释率有利于溶剂的生产。当稀释率为0.05 h 1,4个发酵罐温度控制在37℃时,总溶剂产量为11.57 g/L,其中丁醇7.29 g/L,生产率为0.145 g/(L.h)。在0.05 h 1稀释率的条件下进行变温连续发酵证实低温有利于溶剂的积累,当一级和二级罐温度控制在37℃,三级和四级罐温度控制在33℃时总溶剂产量最高为13.69 g/L,其中丁醇为8.36 g/L,生产率为0.171 g/(L.h)。 展开更多
关键词 clostridium saccharobutylicum 连续发酵 丁醇 稀释率 温度
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Prevalence of diverticulosis in recurrent Clostridium difficile infection
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作者 Michael J Lipp Odelya E Pagovich +2 位作者 David Rabin Albert D Min Brett B Bernstein 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第3期345-347,共3页
AIM:To re-evaluate the theory that colonic diverticulosis is associated with relapse of Clostridium difficile associated disease (CDAD) in light of data suggesting increasing rates of CDAD infection and relapse.METHOD... AIM:To re-evaluate the theory that colonic diverticulosis is associated with relapse of Clostridium difficile associated disease (CDAD) in light of data suggesting increasing rates of CDAD infection and relapse.METHODS: Charts were reviewed for patients with recurrent CDAD who had also had a prior colonoscopy or flexible sigmoidoscopy. An age and gender matched control group was used to compare the prevalence of diverticulosis.RESULTS: Twenty-two patients met the study criteria, and the prevalence of diverticulosis in patients with CDAD relapse was 23% compared to 32% in age and sex matched controls (P=0.44). A significant proportion of patients with CDAD relapse had comorbidities associated with immune suppression.CONCLUSION: Diverticulosis does not appear to be associated with CDAD relapse. 展开更多
关键词 clostridium diff icile DIVERTICULOSIS RELAPSE Immune suppression clostridium difficile associated disease
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Clostridium clariflavum DSM 19732木聚糖酶Xyn2441的克隆表达及条件优化 被引量:4
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作者 胡方觊 余嘉慧 +2 位作者 张庆华 毛忠贵 唐蕾 《食品与发酵工业》 CAS CSCD 北大核心 2016年第7期16-22,共7页
Clostridium clariflavum DSM19732是一种颇具应用价值的木质纤维素降解菌,尤其对半纤维素的降解能力非常高,国外学者已开始关注其中木质纤维素降解酶类的结构与功能,国内尚无相关报道。作者首次从复合菌系RXS基因组DNA中扩增出C.cl... Clostridium clariflavum DSM19732是一种颇具应用价值的木质纤维素降解菌,尤其对半纤维素的降解能力非常高,国外学者已开始关注其中木质纤维素降解酶类的结构与功能,国内尚无相关报道。作者首次从复合菌系RXS基因组DNA中扩增出C.clariflavum DSM19732的一个表达双功能木聚糖酶(糖苷水解酶家族(glycosyl hydrolase family,GH)10和11的木聚糖酶)的基因Clocl-2441,并将其与载体pET28a(+)连接,在大肠杆菌E.coli BL21(DE3)成功表达。重组菌最佳诱导表达条件为:添加诱导剂时的菌体量OD600值约为1.25、诱导剂IPTG浓度为0.5mmol/L、诱导时间7~8h及诱导温度25℃,此时胞内重组酶比酶活达到34.92U/mg。经镍柱初步分离纯化后比酶活达713.16U/mg,纯化倍数20.83倍,回收率27%。重组酶的最适反应温度和pH分别为70℃和6.5。 展开更多
关键词 clostridium clariflavum DSM19732 木聚糖酶 Clocl-2441 克隆表达 大肠杆菌
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响应面分析法优化一株窖泥源酪丁酸梭菌(Clostridium tyrobutyricum)RL1菌株产丁酸发酵培养基 被引量:4
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作者 彭志云 赵东 +4 位作者 胡晓龙 何培新 张勇 郑燕 牛广杰 《酿酒科技》 2019年第10期24-31,共8页
从某浓香型白酒窖泥中筛选出1 株高产丁酸的酪丁酸梭菌(Clostridium tyrobutyricum)RL1 菌株,采用响应面分析法对其产丁酸培养基进行优化研究。首先采用Plackett-Burman 设计对基础培养基中9 个主要因素进行筛选,确定出对丁酸产量影响... 从某浓香型白酒窖泥中筛选出1 株高产丁酸的酪丁酸梭菌(Clostridium tyrobutyricum)RL1 菌株,采用响应面分析法对其产丁酸培养基进行优化研究。首先采用Plackett-Burman 设计对基础培养基中9 个主要因素进行筛选,确定出对丁酸产量影响显著的3 个因素,依次为葡萄糖、碳酸钙和蛋白胨。对上述显著因素利用最陡爬坡试验逼近最大产酸响应区域,最后通过Box-Behnken 设计及响应面分析确定最佳培养基总成分组成为:葡萄糖85.29 g/L,酵母粉7.5 g/L,蛋白胨9.37 g/L,氯化钠7.5 g/L,乙酸钠4.5 g/L,磷酸氢二钾2.5 g/L,七水合硫酸镁0.3 g/L,硫酸铵1.5 g/L,七水合硫酸亚铁0.015 g/L,硫代乙醇酸钠0.5 g/L,碳酸钙11.6 g/L。优化后培养基的丁酸浓度为22.96 g/L,较优化前的14.23 g/L提高了61.35 %。 展开更多
关键词 微生物 clostridium tyrobutyricum RL1 丁酸 响应面法 优化
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Clostridium clariflavum GH10木聚糖酶的克隆表达、酶学性质及位点功能分析 被引量:4
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作者 王华广 刘雨露 +1 位作者 胡方觊 唐蕾 《食品与发酵工业》 CAS CSCD 北大核心 2018年第6期16-23,共8页
首次将来源于Clostridium clariflavum的木聚糖酶基因Clocl-2441中的糖苷水解酶家族10(glycosyl hydrolase families,GH)结构域基因连接到pET28a(+)载体上,在E.coli BL21(DE3)成功异源表达。经镍柱和脱盐分离纯化达到电泳纯,并对其酶学... 首次将来源于Clostridium clariflavum的木聚糖酶基因Clocl-2441中的糖苷水解酶家族10(glycosyl hydrolase families,GH)结构域基因连接到pET28a(+)载体上,在E.coli BL21(DE3)成功异源表达。经镍柱和脱盐分离纯化达到电泳纯,并对其酶学性质进行解析。结果表明,重组木聚糖酶rXyn2441GH10最适温度和pH分别为70℃和7.0,属于中性嗜热木聚糖酶。rXyn2441GH10在65℃以下和pH 4.0~9.0范围比较稳定,金属离子中5 mmol/L的Mg^(2+)可以提高79.2%的酶活。以榉木木聚糖为底物重组酶的动力学参数,V_(max)为1 691.5μmol/(mg·min),K_m值为2.5 mg/mL,k_(cat)为1 236.4/s,k_(cat)/K_m为494.6 mL/(mg·s)。定点饱和突变表明209位点的组氨酸对酶活有重要的作用。 展开更多
关键词 clostridium clariflavum Glycosyl HYDROLASE families 10木聚糖酶 大肠杆菌 定点饱和突变
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宁波沿海陆源排污口弓形杆菌属(Arobacter sp.)和梭菌属(Clostridium sp.)的分布特点 被引量:8
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作者 王祖忠 王朝阳 +7 位作者 张迪骏 司开学 董丽莎 张红燕 崔晨茜 韩姣姣 周君 苏秀榕 《海洋与湖沼》 CAS CSCD 北大核心 2016年第4期862-868,共7页
弓形杆菌属(Arobacter sp.)和梭菌属(Clostridium sp.)广泛存在于水体和寄生在动物体内,极易造成水体污染和人畜共患病。采用高通量454焦磷酸测序方法对宁波沿海2个重点排污口、8个一般排污口的20个站位水样进行分析,得到1年中的3月、5... 弓形杆菌属(Arobacter sp.)和梭菌属(Clostridium sp.)广泛存在于水体和寄生在动物体内,极易造成水体污染和人畜共患病。采用高通量454焦磷酸测序方法对宁波沿海2个重点排污口、8个一般排污口的20个站位水样进行分析,得到1年中的3月、5月、8月和10月份各排污口弓形杆菌属和梭菌属生物的分布情况。研究结果表明:弓形杆菌属检测出两个种,分别是嗜低温弓形杆菌(Arcobacter cryaerophilus)、布氏弓形杆菌(Arcobacter butzleri)。梭菌属共检测出12个种,其中产气荚膜梭菌(Clostridium perfringens)检出次数最高,丁酸梭菌(Clostridium butyricum)次之;排污口的类型是影响弓形杆菌属检出量的重要因素。弓形杆菌属主要分布在氮,磷含量较高的工业排污口和市政排污口,而梭菌属只在3月份的S7宁海西店崔家综合排污口呈现出相对较高的比例(7.5%),其它排污口检出量均在2%以下;弓形杆菌属和梭菌属在10个排污口20个站位4个月份的检出次数呈现正相关性;由季节性的变化引起的气温差异也是影响弓形杆菌属生长的重要因素,弓形杆菌属在5月份的时候检出次数最大,梭菌属适宜生长温度范围较广10—65°C,受温度影响较小。 展开更多
关键词 弓形杆菌属 梭菌属 454焦磷酸测序 陆源排污口 检出次数
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