This study was performed to determine the effects of bacteriocin-producing and non-bacteriocin-producing Pediococcus acidilactici strains on the immune system and intestinal flora of normal mice.Two P.acidilactici str...This study was performed to determine the effects of bacteriocin-producing and non-bacteriocin-producing Pediococcus acidilactici strains on the immune system and intestinal flora of normal mice.Two P.acidilactici strains with antibacterial activity(P.acidilactici CCFM28 and CCFM18)were obtained based on the inhibition-zone assay.The produced components were identified as bacteriocins through protease treatment,pH adjustment and hydrogen peroxide treatment.Bacteriocin-producing and non-bacteriocin-producing P.acidilactici strains(P.acidilactici CCFM28,CCFM18 and NT17-3)caused significant changes in serum immune factors and intestinal flora of normal mice.After 14 days of intervention,the relative abundance of Firmicutes was significantly decreased,but that of Proteobacteria was significantly increased at the phylum level.At the genus level,the administration of three P.acidilactici strains resulted in the downregulation of Blautia and the upregulation of Ruminococcus and Lactobacillus.Furthermore,there were also different regulations on some probiotic strains,such as Bifidobacterium,Coprococcus and Akkermansia,which were closely related to the antibacterial ability of the bacteriocin and the type of strain.The results indicated that the intervention of different P.acidilactici strains could differently change the structure of intestinal flora in normal mice,which provided theoretical guidance for the selective use of bacteriocin-producing strains for health regulation in the future.展开更多
Biodetoxification fungus selectively degrades toxic inhibitors generated from pretreatment of lignocellulose without consuming fermentable sugars.However,one barrier for practical application is the sustained cell via...Biodetoxification fungus selectively degrades toxic inhibitors generated from pretreatment of lignocellulose without consuming fermentable sugars.However,one barrier for practical application is the sustained cell viability in the consequent fermentation step to compete the fermentable sugars with fermenting strains,resulting in sugar loss and reduced target product yield.This study investigated the competitive growth property between the biodetoxification fungus Paecilomyces variotii FN89 and the L-lactic acid bacterium Pediococcus acidilactici ZY271 under varying temperature and lactic acid osmatic stress.The results show that the L-lactic acid bacterium Ped.acidilactici ZY271 showed less thermotolerance to Pae.variotii FN89 at high temperature of 45°C to 50°C in both synthetic medium and wheat straw hydrolysate.In the higher temperature environment,the growth of the biodetoxification strian failed to compete with the lactic acid fermentation strain and was quickly eliminated from the fermentation system.The high temperature fermentation facilitated a fast transition from the detoxification stage to the fermentation stage for higher production of L-lactic acid.展开更多
Microbial fermentation could produce many active substances in green and pollution-free ways.In recent years,studies on the hypoglycemic ability of microorganisms had become a trending topic in the prevention and trea...Microbial fermentation could produce many active substances in green and pollution-free ways.In recent years,studies on the hypoglycemic ability of microorganisms had become a trending topic in the prevention and treatment of diabetes.Garlic is a food containing a variety of biologically active substances and physiological functions,but it is not accepted by the general public because of its strong pungent smell.In our study,the microorganisms with potential hypoglycemic effect were screened from strains resistant to garlic juice.As a result,41 strains of Bacillus,157 strains of lactic acid bacteria,and 23 strains of yeast with tolerance of garlic juice were screened from the selected 568 strains.After primary screening ofα-amylase inhibitor,it was found that 15 Bacillus and 9 lactic acid bacteria had highα-amylase inhibitory activity.Besides,afterα-glucosidase inhibitor re-screening,Pediococcus acidilactici Z1 with highα-amylase inhibitory activity andα-glucosidase inhibitory activity was screened out.The results of fermented garlic showed that the inhibition rate ofα-amylase andα-glucosidase of garlic from different origins were significantly increased from 59.09 to 63.99%(p<0.01)and from 52.71 to 71.93%(p<0.01)after Z1 fermentation,respectively.The improvement rates ofα-amylase andα-glucosidase were 107.69 to 287.32%,and 197.74 to 239.86%,respectively.In a word,this study provides a theoretical and experimental basis for the development of new functional garlic products.展开更多
基金supported by the National Natural Science Foundation of China Program(32021005)the Natural Science Foundation of Jiangsu Province(BK20200084)+2 种基金Projects of Innovation and Development Pillar Program for Key Industries in Southern Xinjiang of Xinjiang Production and Construction Corps(2018DB002)National First Class Discipline Program of Food Science and Technology(JUFSTR20180102)the Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province。
文摘This study was performed to determine the effects of bacteriocin-producing and non-bacteriocin-producing Pediococcus acidilactici strains on the immune system and intestinal flora of normal mice.Two P.acidilactici strains with antibacterial activity(P.acidilactici CCFM28 and CCFM18)were obtained based on the inhibition-zone assay.The produced components were identified as bacteriocins through protease treatment,pH adjustment and hydrogen peroxide treatment.Bacteriocin-producing and non-bacteriocin-producing P.acidilactici strains(P.acidilactici CCFM28,CCFM18 and NT17-3)caused significant changes in serum immune factors and intestinal flora of normal mice.After 14 days of intervention,the relative abundance of Firmicutes was significantly decreased,but that of Proteobacteria was significantly increased at the phylum level.At the genus level,the administration of three P.acidilactici strains resulted in the downregulation of Blautia and the upregulation of Ruminococcus and Lactobacillus.Furthermore,there were also different regulations on some probiotic strains,such as Bifidobacterium,Coprococcus and Akkermansia,which were closely related to the antibacterial ability of the bacteriocin and the type of strain.The results indicated that the intervention of different P.acidilactici strains could differently change the structure of intestinal flora in normal mice,which provided theoretical guidance for the selective use of bacteriocin-producing strains for health regulation in the future.
基金The National Key R&D Program of China(2023YFA0914400)the National Natural Science Foundation of China(32301269)+1 种基金China Postdoctoral Science Foundation(2023M741175)the Yangfan Project of Science and Technology Committee of Shanghai Municipality(23YF1409900).
文摘Biodetoxification fungus selectively degrades toxic inhibitors generated from pretreatment of lignocellulose without consuming fermentable sugars.However,one barrier for practical application is the sustained cell viability in the consequent fermentation step to compete the fermentable sugars with fermenting strains,resulting in sugar loss and reduced target product yield.This study investigated the competitive growth property between the biodetoxification fungus Paecilomyces variotii FN89 and the L-lactic acid bacterium Pediococcus acidilactici ZY271 under varying temperature and lactic acid osmatic stress.The results show that the L-lactic acid bacterium Ped.acidilactici ZY271 showed less thermotolerance to Pae.variotii FN89 at high temperature of 45°C to 50°C in both synthetic medium and wheat straw hydrolysate.In the higher temperature environment,the growth of the biodetoxification strian failed to compete with the lactic acid fermentation strain and was quickly eliminated from the fermentation system.The high temperature fermentation facilitated a fast transition from the detoxification stage to the fermentation stage for higher production of L-lactic acid.
基金supported by the program of Key Laboratory of Industrial Biotechnology of Ministry of Education in Jiangnan University(KLIB-KF202105)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)+1 种基金Program of Introducing Talents of Discipline to Universities(No.111-2-06)the National High Technology Research and Development Program 863(No.2018YFD0400403).
文摘Microbial fermentation could produce many active substances in green and pollution-free ways.In recent years,studies on the hypoglycemic ability of microorganisms had become a trending topic in the prevention and treatment of diabetes.Garlic is a food containing a variety of biologically active substances and physiological functions,but it is not accepted by the general public because of its strong pungent smell.In our study,the microorganisms with potential hypoglycemic effect were screened from strains resistant to garlic juice.As a result,41 strains of Bacillus,157 strains of lactic acid bacteria,and 23 strains of yeast with tolerance of garlic juice were screened from the selected 568 strains.After primary screening ofα-amylase inhibitor,it was found that 15 Bacillus and 9 lactic acid bacteria had highα-amylase inhibitory activity.Besides,afterα-glucosidase inhibitor re-screening,Pediococcus acidilactici Z1 with highα-amylase inhibitory activity andα-glucosidase inhibitory activity was screened out.The results of fermented garlic showed that the inhibition rate ofα-amylase andα-glucosidase of garlic from different origins were significantly increased from 59.09 to 63.99%(p<0.01)and from 52.71 to 71.93%(p<0.01)after Z1 fermentation,respectively.The improvement rates ofα-amylase andα-glucosidase were 107.69 to 287.32%,and 197.74 to 239.86%,respectively.In a word,this study provides a theoretical and experimental basis for the development of new functional garlic products.
