The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many o...The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many other aspects.Exploring the structure and function of the gut microbiota,as well as their key genes and metabolites,will enable the early diagnosis and auxiliary diagnosis of diseases,new treatment methods,better effects of drug treatments,and better guidance in the use of antibiotics.The identification of gut microbiota plays an important role in clinical diagnosis and treatment,as well as in drug research and development.Therefore,it is necessary to conduct a comprehensive review of this rapidly evolving topic.Traditional identification methods cannot comprehensively capture the diversity of gut microbiota.Currently,with the rapid development of molecular biology,the classification and identification methods for gut microbiota have evolved from the initial phenotypic and chemical identification to identification at the molecular level.This review integrates the main methods of gut microbiota identification and evaluates their application.We pay special attention to the research progress on molecular biological methods and focus on the application of high-throughput sequencing technology in the identification of gut microbiota.This revolutionary method for intestinal flora identification heralds a new chapter in our understanding of the microbial world.展开更多
Six strains of moderately thermophilic sulfur-oxidizing bacteria were isolated from several different typical environments in China. The identities of the isolates were confirmed by analyses of their 16S rRNA genes, a...Six strains of moderately thermophilic sulfur-oxidizing bacteria were isolated from several different typical environments in China. The identities of the isolates were confirmed by analyses of their 16S rRNA genes, and some key physiological traits. The isolates are Gram negative, rod-shaped bacteria, their optimal temperature and pH value for growth are 45-50℃ and 2.5-3.5 respectively. They are autotrophic and used elemental sulfur, sodium thiosulfate and potassium tetrathionate as electron donor, while a little glucose stimulated their growth. 16S rDNA sequences analysis reveals that the strains are phylogenetically clustered to Acidithiobacillus caldus.展开更多
目的探讨益生菌对大鼠酒精性肝损伤的保护作用。方法建立酒精性肝损伤模型,同时以碧悠益生菌发酵乳5×108CFU·kg-1·d-1灌胃干预,持续8周。HE染色观察各组大鼠肝组织病理学改变;透射电镜观察肝及小肠组织超微结构变化;酶...目的探讨益生菌对大鼠酒精性肝损伤的保护作用。方法建立酒精性肝损伤模型,同时以碧悠益生菌发酵乳5×108CFU·kg-1·d-1灌胃干预,持续8周。HE染色观察各组大鼠肝组织病理学改变;透射电镜观察肝及小肠组织超微结构变化;酶法检测血清转氨酶及ALP活力;ELISA法检测血清DAO和D-LA水平;免疫组化法检测小肠组织FOXO4表达情况;16S r DNA高通量测序进行粪便肠道菌群结构分子生态学分析。结果益生菌干预使酒精诱导的肝脂肪变性得到明显缓解,肝及小肠组织超微结构亦得到不同程度改善,其病理学评分明显降低(P<0.05);同时,血清ALT、AST、ALP、DAO和D-LA水平均明显下降,小肠FOXO4表达明显提高(P<0.05)。益生菌干预在肠道菌群菌门、菌属水平均较酒精模型组有不同程度改变,丰度最高的前20个菌属与正常对照组一致率达到90%,对恢复肠道菌群多样性及丰度正常状态具有一定调节作用。结论益生菌对大鼠酒精性肝损伤具有一定保护作用,其作用机制可能与益生菌纠正肠道菌群结构紊乱,修复肠道屏障功能,改善肠道内环境有关。展开更多
为有效降解烟叶中的纤维素,改善烟叶的整体品质,从不同产地原烟表面初步分离出具有降解纤维素能力的菌株;通过测定菌株所产纤维素酶活性,筛选高产纤维素酶菌株并进行16 S rDNA测序,结合生理生化试验对其进行鉴定;进一步采用正交试验优...为有效降解烟叶中的纤维素,改善烟叶的整体品质,从不同产地原烟表面初步分离出具有降解纤维素能力的菌株;通过测定菌株所产纤维素酶活性,筛选高产纤维素酶菌株并进行16 S rDNA测序,结合生理生化试验对其进行鉴定;进一步采用正交试验优化菌株在烟叶中的发酵条件,考察烟叶中纤维素降解效果。结果表明:1)在分离得到的18株菌株中,XC-19-1产纤维素酶活性最高(6.6 U·mL^(-1));2)16 S rDNA测序以及生理生化试验推断,XC-19-1为枯草芽孢杆菌(Bacillus subtilis);3)根据正交试验的结果,将培养后的XC-19-1菌液按照3%的烟叶质量比例施加于抽梗后的烟叶表面,在温度为37℃、相对湿度为75%的条件下作用60 h后,烟叶中的纤维素降解率可达30.6%,总糖以及还原糖含量均有明显提高,有效提升烟叶整体质量。展开更多
文摘The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many other aspects.Exploring the structure and function of the gut microbiota,as well as their key genes and metabolites,will enable the early diagnosis and auxiliary diagnosis of diseases,new treatment methods,better effects of drug treatments,and better guidance in the use of antibiotics.The identification of gut microbiota plays an important role in clinical diagnosis and treatment,as well as in drug research and development.Therefore,it is necessary to conduct a comprehensive review of this rapidly evolving topic.Traditional identification methods cannot comprehensively capture the diversity of gut microbiota.Currently,with the rapid development of molecular biology,the classification and identification methods for gut microbiota have evolved from the initial phenotypic and chemical identification to identification at the molecular level.This review integrates the main methods of gut microbiota identification and evaluates their application.We pay special attention to the research progress on molecular biological methods and focus on the application of high-throughput sequencing technology in the identification of gut microbiota.This revolutionary method for intestinal flora identification heralds a new chapter in our understanding of the microbial world.
基金Project (50321402) supported by the National Natural Science Foundation of China Project(2004CB619204) supported by the State Basic Research Development Program of China Project (DY105-02-04-05) supported by the China Ocean Mineral Resources Research and Development Association
文摘Six strains of moderately thermophilic sulfur-oxidizing bacteria were isolated from several different typical environments in China. The identities of the isolates were confirmed by analyses of their 16S rRNA genes, and some key physiological traits. The isolates are Gram negative, rod-shaped bacteria, their optimal temperature and pH value for growth are 45-50℃ and 2.5-3.5 respectively. They are autotrophic and used elemental sulfur, sodium thiosulfate and potassium tetrathionate as electron donor, while a little glucose stimulated their growth. 16S rDNA sequences analysis reveals that the strains are phylogenetically clustered to Acidithiobacillus caldus.
文摘目的探讨益生菌对大鼠酒精性肝损伤的保护作用。方法建立酒精性肝损伤模型,同时以碧悠益生菌发酵乳5×108CFU·kg-1·d-1灌胃干预,持续8周。HE染色观察各组大鼠肝组织病理学改变;透射电镜观察肝及小肠组织超微结构变化;酶法检测血清转氨酶及ALP活力;ELISA法检测血清DAO和D-LA水平;免疫组化法检测小肠组织FOXO4表达情况;16S r DNA高通量测序进行粪便肠道菌群结构分子生态学分析。结果益生菌干预使酒精诱导的肝脂肪变性得到明显缓解,肝及小肠组织超微结构亦得到不同程度改善,其病理学评分明显降低(P<0.05);同时,血清ALT、AST、ALP、DAO和D-LA水平均明显下降,小肠FOXO4表达明显提高(P<0.05)。益生菌干预在肠道菌群菌门、菌属水平均较酒精模型组有不同程度改变,丰度最高的前20个菌属与正常对照组一致率达到90%,对恢复肠道菌群多样性及丰度正常状态具有一定调节作用。结论益生菌对大鼠酒精性肝损伤具有一定保护作用,其作用机制可能与益生菌纠正肠道菌群结构紊乱,修复肠道屏障功能,改善肠道内环境有关。
文摘为有效降解烟叶中的纤维素,改善烟叶的整体品质,从不同产地原烟表面初步分离出具有降解纤维素能力的菌株;通过测定菌株所产纤维素酶活性,筛选高产纤维素酶菌株并进行16 S rDNA测序,结合生理生化试验对其进行鉴定;进一步采用正交试验优化菌株在烟叶中的发酵条件,考察烟叶中纤维素降解效果。结果表明:1)在分离得到的18株菌株中,XC-19-1产纤维素酶活性最高(6.6 U·mL^(-1));2)16 S rDNA测序以及生理生化试验推断,XC-19-1为枯草芽孢杆菌(Bacillus subtilis);3)根据正交试验的结果,将培养后的XC-19-1菌液按照3%的烟叶质量比例施加于抽梗后的烟叶表面,在温度为37℃、相对湿度为75%的条件下作用60 h后,烟叶中的纤维素降解率可达30.6%,总糖以及还原糖含量均有明显提高,有效提升烟叶整体质量。
