title: Antibacterial action of selenium-enriched probiotics against pathogenic Escherichia coli.
abstract: The purpose of this study was to evaluate the inhibitory activity of selenium-enriched probiotics against pathogenic Escherichia coli (E. coli) in vitro and in vivo. Escherichia coli was co-cultured in vitro with each probiotic strain individually, and a mixture of the four strains and its population was counted at various time points. We also collected a cell-free culture supernatant (CFCS) of each probiotic strain and the four-strain mix to examine their antibacterial activity, using the cylinder plate method. Results demonstrated that co-culture with probiotics significantly reduced the number of E. coli. The different sizes of the inhibition zones made by each CFCS proved that E. coli was inhibited by the metabolites of the probiotics. In vivo, Kunming mice were allocated to different groups supplemented with selenium-enriched and other probiotics. After 28 days, the mice were inoculated with pathogenic E. coli so that we could compare mortality rates and inspect other indexes of each treatment. The mortality of the group with selenium-enriched probiotics was the lowest. In addition, the organic antioxidant status improved, immunity was fortified, and the internal environment of the intestinal tract was enhanced with selenium-enriched probiotic supplementation. In conclusion, selenium-enriched probiotics can strongly antagonize pathogenic E. coli in vitro and in vivo.
authors.affiliation: Institute of Nutritional and Metabolic Disorders, Nanjing Agricultural University, Nanjing, China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Yang
authors.forename: Kehe
authors.initials: K
authors.lastname: Huang
authors.forename: Shunyi
authors.initials: S
authors.lastname: Qin
authors.forename: Xianshi
authors.initials: X
authors.lastname: Wu
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Zhao
authors.forename: Fu
authors.initials: F
authors.lastname: Chen
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002175:Candida / Q000378:metabolism; D018920:Coculture Techniques; D017077:Culture Media, Conditioned / Q000494:pharmacology; D003967:Diarrhea / Q000382:microbiology / Q000517:prevention & control; D004357:Drug Synergism; D004926:Escherichia coli / Q000187:drug effects*; D004927:Escherichia coli Infections / Q000473:pathology / Q000517:prevention & control; D005260:Female; D041981:Gastrointestinal Tract / Q000737:chemistry / Q000382:microbiology; D006094:Gram-Positive Bacteria / Q000254:growth & development / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007779:Lactobacillus acidophilus / Q000254:growth & development / Q000378:metabolism; D052201:Lacticaseibacillus rhamnosus / Q000254:growth & development / Q000378:metabolism; D007928:Lethal Dose 50; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D051379:Mice; D019936:Probiotics / Q000494:pharmacology* / Q000627:therapeutic use; D012643:Selenium / Q000378:metabolism* / Q000627:therapeutic use; D018036:Selenium Compounds / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D013154:Spleen / Q000473:pathology; D048249:Streptococcus thermophilus / Q000254:growth & development / Q000378:metabolism; D013950:Thymus Gland / Q000473:pathology
chemical_list: D000975:Antioxidants; D017077:Culture Media, Conditioned; D018036:Selenium Compounds; D008315:Malondialdehyde; D012643:Selenium