Molecular diversity and development of the Lactobacillus community in the intestinal tract, as influenced by age and intestinal compartment, were studied in one litter of 12 conventionally raised piglets. Piglets were...Molecular diversity and development of the Lactobacillus community in the intestinal tract, as influenced by age and intestinal compartment, were studied in one litter of 12 conventionally raised piglets. Piglets were euthanized at each week (3 animals per time). Digesta and tissue samples from stomach, duodenum, jejunum, ileum, caecum, colon, and rectum were collected and analysed by using 16S ribosomal RNA-based methods. DGGE (denaturing gradient gel electrophoresis) profiles revealed that the Lactobacillus communities throughout the GI tract from duodenum to rectum showed good stability at same age. This indicates that fecal Lactobacillus communities can effectively represent the intestinal community. Two dominant bands were found in tissue samples of the small intestine, suggesting that the lactobacilli can adhere to the small intestinal wall. The Lactobacillus communities in different GI tract compartments developed over time. A successional change of Lactobacillus communities was observed from birth, through creep feeding to one week after weaning, showing a trend from simple to complex and back to simple. Furthermore, a clone library of Lactobacillus spp. 16S rRNA gene sequences were generated from jejunal and colonic chymes. Six dominant DGGE bands generated from jejunal chymes were matched with sequences that show 94-98% similarity to the bands derived from L. reuteri, L. delbrueckii, and L. crispatus. Seven dominant DGGE bands generated from colon chymes were matched with sequences that show 88-99% similarity to those derived from L. reuteri, L. delbrueckii, L. amylovorus/L. sobrius, and L. acidophilus. Amplicons related to L. reuteri were found in all DGGE fingerprints from jejunal digesta of age of weeks 1, 3, and 4. Amplicons related to L. amylovorus/L. sobrius were present in all DGGE fingerprints from colonic digesta of age of week 1, 3, and 4. Amplicons related to L. delbrueckii were found before weaning, L. crispatus after creep feeding before weaning and L. acidophilus after weaning. Thi展开更多
添加分离自酸菜发酵液的干酪乳杆菌(Lactobacillus casei)HDS-01构建酸菜发酵微生物生态体系,利用高效液相色谱法、酸碱滴定法、高通量测序和实时定量PCR技术结合传统酶学分析方法等,研究酸菜发酵过程中理化因子和微生物群落的动态变化...添加分离自酸菜发酵液的干酪乳杆菌(Lactobacillus casei)HDS-01构建酸菜发酵微生物生态体系,利用高效液相色谱法、酸碱滴定法、高通量测序和实时定量PCR技术结合传统酶学分析方法等,研究酸菜发酵过程中理化因子和微生物群落的动态变化,评价L. casei HDS-01对酸菜品质及安全性的影响。结果表明,添加L. casei HDS-01发酵酸菜的pH在第3 d就下降至3.15±0.08,发酵初期乳酸菌数为(7.63±0.19)lg CFU/mL。在发酵酸菜各时期,乳酸代谢途径关键酶活力均显著高于自然发酵酸菜(P<0.05)。在发酵末期,乳酸、总酸和VC含量分别为(7.88±0.38)、(8.45±0.38) g/L和(445.02±10.53)mg/kg,亚硝酸盐含量为(1.55±0.86)mg/kg。对酸菜样品进行感官评价发现,L. casei HDS-01发酵酸菜从发酵液清澈度、酸菜的色泽、香气、口味以及脆度等方面均优于自然发酵酸菜。此外,L. casei HDS-01发酵酸菜中乳杆菌属(Lactobacillus)始终保持优势地位(63.36%~95.79%),降低了肠杆菌属(Enterobacter)(0.04%~2.26%)和假单胞菌属(Pseudomonas)(0.28%~25.84%)等致病菌丰度,调控了菌群多样性,缩短了发酵进程。本研究对发酵用菌种资源和功能菌的开发具有重要的实践意义。展开更多
Improving silage production by adding exogenous microorganisms not only maximizes nutrient preservation,but also extends product shelf life.Herein,changes in the quality and quantity of Lactobacillus plantarum PS-8(PS...Improving silage production by adding exogenous microorganisms not only maximizes nutrient preservation,but also extends product shelf life.Herein,changes in the quality and quantity of Lactobacillus plantarum PS-8(PS-8)-inoculated alfalfa(Medicago sativa)during silage fermentation were monitored at d 0,7,14,and 28(inoculum dose of PS-8 was 1105 colony forming units[cfu]/g fresh weight;50 kg per bag;10 bags for each time point)by reconstructing metagenomic-assembled genomes(MAG)and Growth Rate InDex(GRiD).Our results showed that the exogenous starter bacterium,PS-8 inoculation,became the most dominating strain by d 7,and possibly played a highly active role throughout the fermentation process.The pH value of the silage decreased greatly,accompanied by the growth of acidproducing microorganisms namely PS-8,which inhibited the growth of harmful microorganisms like molds(4.18 vs.1.42 log cfu/g)and coliforms(4.95 vs.0.66 log most probable number[MPN]/g).The content of neutral detergent fiber(NDF)decreased significantly(41.6%vs.37.6%;dry matter basis).In addition,the abundance and diversity of genes coding microbial carbohydrate-active enzymes(CAZymes)increased significantly and desirably throughout the fermentation,particularly the genes responsible for degrading starch,arabino-xylan,and cellulose.Overall,our results showed that PS-8 was replicating rapidly and consistently during early-and mid-fermentation phases,promoting the growth of beneficial lactic acid bacteria and inhibiting undesirable microbes,ultimately improving the quality of silage.展开更多
Objective To investigate the features of vaginal bacteria community in women with recurrent vulvovaginal candidiasis (R VVC) and its etiological risk in vaginal health. Methods Totally 237 reproductive-aged women wi...Objective To investigate the features of vaginal bacteria community in women with recurrent vulvovaginal candidiasis (R VVC) and its etiological risk in vaginal health. Methods Totally 237 reproductive-aged women with RVVC in an acute episode were studied. Whereas 230 healthy reproductive-aged women were enrolled as the control. The vaginal pH was evaluated, while vaginal secretions were sampled for Gram's staining and oilmicroscopy. By Nugent score system, the composition of vaginal communities was determined, and other micro-ecological features were approached. To describe other features of vaginal microbiota, the community's bacteria density, species diversity and predominant species were evaluated at 1 000 X magnification. Results The vaginal pH (4.53 ~ 0.30) and Nugent score (4.31 ___+ O. 73) in RVVC group were significantly increased compared with vaginal pH (4.11 __+ 0.30) and Nugent score (1.32 _+ 1.29) in control group (P〈O.05, respectively). The density of Lactoba- cillus in RVVC group was significantly lower than that in control group (P〈O.05), while the densities of Gardnerella vaginalis, Gram-positive cocci and other species were significantly higher respectively than those in control group (P〈O. 05). Species diversity of women with RVVC significantly exceeded that of control group (P〈O.05). More than half of vaginal communities in R VVC group lost Lactobacillus-dominating and were predominated by other bacteria such as Gardnerella vaginalis and Gram-positive cocci. The prevalence of Gardnerella vaginalis-dominating and Gram-positive cocci-domi- nating communities in RVVC group (37.55% and 19.83%) were significantly higher than those in control group (1.30% and 1.73%) (P〈0.05). Conclusion The significant changes in vaginal bacterial community were observed in RVVC women. Such variations in community might relate to vaginal biological barrier compromising and increase the risk to the recurrence of VVC. It is still controversial whethe展开更多
萝卜盐渍是一种有效的萝卜加工技术,对萝卜产业化发展具有十分重要的意义。采用变性梯度凝胶电泳技术(denatured gradient gel electrophoresis,DGGE)对腌渍178天与539天的盐渍萝卜及其盐渍水的细菌菌群结构分析表明,两种腌渍时间的盐...萝卜盐渍是一种有效的萝卜加工技术,对萝卜产业化发展具有十分重要的意义。采用变性梯度凝胶电泳技术(denatured gradient gel electrophoresis,DGGE)对腌渍178天与539天的盐渍萝卜及其盐渍水的细菌菌群结构分析表明,两种腌渍时间的盐渍萝卜的细菌菌群结构相似,优势菌群均为乳杆菌,基因水平上呈多样性。DGGE操作简便,能够较好地反映盐渍萝卜的细菌菌群变化,在盐渍萝卜的细菌菌群结构分析中具有独特的优势。展开更多
基金supported by the National Natural Science Foundation of China (30771570)the Natural Science Foundation of Jiangsu Province, China(BK2006143)
文摘Molecular diversity and development of the Lactobacillus community in the intestinal tract, as influenced by age and intestinal compartment, were studied in one litter of 12 conventionally raised piglets. Piglets were euthanized at each week (3 animals per time). Digesta and tissue samples from stomach, duodenum, jejunum, ileum, caecum, colon, and rectum were collected and analysed by using 16S ribosomal RNA-based methods. DGGE (denaturing gradient gel electrophoresis) profiles revealed that the Lactobacillus communities throughout the GI tract from duodenum to rectum showed good stability at same age. This indicates that fecal Lactobacillus communities can effectively represent the intestinal community. Two dominant bands were found in tissue samples of the small intestine, suggesting that the lactobacilli can adhere to the small intestinal wall. The Lactobacillus communities in different GI tract compartments developed over time. A successional change of Lactobacillus communities was observed from birth, through creep feeding to one week after weaning, showing a trend from simple to complex and back to simple. Furthermore, a clone library of Lactobacillus spp. 16S rRNA gene sequences were generated from jejunal and colonic chymes. Six dominant DGGE bands generated from jejunal chymes were matched with sequences that show 94-98% similarity to the bands derived from L. reuteri, L. delbrueckii, and L. crispatus. Seven dominant DGGE bands generated from colon chymes were matched with sequences that show 88-99% similarity to those derived from L. reuteri, L. delbrueckii, L. amylovorus/L. sobrius, and L. acidophilus. Amplicons related to L. reuteri were found in all DGGE fingerprints from jejunal digesta of age of weeks 1, 3, and 4. Amplicons related to L. amylovorus/L. sobrius were present in all DGGE fingerprints from colonic digesta of age of week 1, 3, and 4. Amplicons related to L. delbrueckii were found before weaning, L. crispatus after creep feeding before weaning and L. acidophilus after weaning. Thi
文摘添加分离自酸菜发酵液的干酪乳杆菌(Lactobacillus casei)HDS-01构建酸菜发酵微生物生态体系,利用高效液相色谱法、酸碱滴定法、高通量测序和实时定量PCR技术结合传统酶学分析方法等,研究酸菜发酵过程中理化因子和微生物群落的动态变化,评价L. casei HDS-01对酸菜品质及安全性的影响。结果表明,添加L. casei HDS-01发酵酸菜的pH在第3 d就下降至3.15±0.08,发酵初期乳酸菌数为(7.63±0.19)lg CFU/mL。在发酵酸菜各时期,乳酸代谢途径关键酶活力均显著高于自然发酵酸菜(P<0.05)。在发酵末期,乳酸、总酸和VC含量分别为(7.88±0.38)、(8.45±0.38) g/L和(445.02±10.53)mg/kg,亚硝酸盐含量为(1.55±0.86)mg/kg。对酸菜样品进行感官评价发现,L. casei HDS-01发酵酸菜从发酵液清澈度、酸菜的色泽、香气、口味以及脆度等方面均优于自然发酵酸菜。此外,L. casei HDS-01发酵酸菜中乳杆菌属(Lactobacillus)始终保持优势地位(63.36%~95.79%),降低了肠杆菌属(Enterobacter)(0.04%~2.26%)和假单胞菌属(Pseudomonas)(0.28%~25.84%)等致病菌丰度,调控了菌群多样性,缩短了发酵进程。本研究对发酵用菌种资源和功能菌的开发具有重要的实践意义。
基金the China Agriculture Research System of MOF and MARA and Inner Mongolia Autonomous Region Science and Technology Achievement Transformation Project(2019CG027).
文摘Improving silage production by adding exogenous microorganisms not only maximizes nutrient preservation,but also extends product shelf life.Herein,changes in the quality and quantity of Lactobacillus plantarum PS-8(PS-8)-inoculated alfalfa(Medicago sativa)during silage fermentation were monitored at d 0,7,14,and 28(inoculum dose of PS-8 was 1105 colony forming units[cfu]/g fresh weight;50 kg per bag;10 bags for each time point)by reconstructing metagenomic-assembled genomes(MAG)and Growth Rate InDex(GRiD).Our results showed that the exogenous starter bacterium,PS-8 inoculation,became the most dominating strain by d 7,and possibly played a highly active role throughout the fermentation process.The pH value of the silage decreased greatly,accompanied by the growth of acidproducing microorganisms namely PS-8,which inhibited the growth of harmful microorganisms like molds(4.18 vs.1.42 log cfu/g)and coliforms(4.95 vs.0.66 log most probable number[MPN]/g).The content of neutral detergent fiber(NDF)decreased significantly(41.6%vs.37.6%;dry matter basis).In addition,the abundance and diversity of genes coding microbial carbohydrate-active enzymes(CAZymes)increased significantly and desirably throughout the fermentation,particularly the genes responsible for degrading starch,arabino-xylan,and cellulose.Overall,our results showed that PS-8 was replicating rapidly and consistently during early-and mid-fermentation phases,promoting the growth of beneficial lactic acid bacteria and inhibiting undesirable microbes,ultimately improving the quality of silage.
文摘Objective To investigate the features of vaginal bacteria community in women with recurrent vulvovaginal candidiasis (R VVC) and its etiological risk in vaginal health. Methods Totally 237 reproductive-aged women with RVVC in an acute episode were studied. Whereas 230 healthy reproductive-aged women were enrolled as the control. The vaginal pH was evaluated, while vaginal secretions were sampled for Gram's staining and oilmicroscopy. By Nugent score system, the composition of vaginal communities was determined, and other micro-ecological features were approached. To describe other features of vaginal microbiota, the community's bacteria density, species diversity and predominant species were evaluated at 1 000 X magnification. Results The vaginal pH (4.53 ~ 0.30) and Nugent score (4.31 ___+ O. 73) in RVVC group were significantly increased compared with vaginal pH (4.11 __+ 0.30) and Nugent score (1.32 _+ 1.29) in control group (P〈O.05, respectively). The density of Lactoba- cillus in RVVC group was significantly lower than that in control group (P〈O.05), while the densities of Gardnerella vaginalis, Gram-positive cocci and other species were significantly higher respectively than those in control group (P〈O. 05). Species diversity of women with RVVC significantly exceeded that of control group (P〈O.05). More than half of vaginal communities in R VVC group lost Lactobacillus-dominating and were predominated by other bacteria such as Gardnerella vaginalis and Gram-positive cocci. The prevalence of Gardnerella vaginalis-dominating and Gram-positive cocci-domi- nating communities in RVVC group (37.55% and 19.83%) were significantly higher than those in control group (1.30% and 1.73%) (P〈0.05). Conclusion The significant changes in vaginal bacterial community were observed in RVVC women. Such variations in community might relate to vaginal biological barrier compromising and increase the risk to the recurrence of VVC. It is still controversial whethe
文摘萝卜盐渍是一种有效的萝卜加工技术,对萝卜产业化发展具有十分重要的意义。采用变性梯度凝胶电泳技术(denatured gradient gel electrophoresis,DGGE)对腌渍178天与539天的盐渍萝卜及其盐渍水的细菌菌群结构分析表明,两种腌渍时间的盐渍萝卜的细菌菌群结构相似,优势菌群均为乳杆菌,基因水平上呈多样性。DGGE操作简便,能够较好地反映盐渍萝卜的细菌菌群变化,在盐渍萝卜的细菌菌群结构分析中具有独特的优势。