Regulatory Effect of Probiotics on Intestinal Flora Disorder Evaluated by FISH-FC

Objective: To explore the effect of mixed Lactobacillus acidophilus and Lactobacillus plantarum cultures(1:1,V/V) on intestinal flora disorder in mice by fluorescence in situ hybridization combined with flow cytometry(FISH-FC) and to elucidate the regulation mechanisms.Methods: The inhibitory activity of the mixture on pathogenic bacteria was determined in vitro.Antibiotic-associated diarrhea mouse model was established by giving specific-pathogen-free(SPF) mice drinking water containing clindamycin hydrochloride at the dose of 2.8 mg/mL for 7 days.Predominant bacteria such as Enterobacteriaceae,C.coccoides-E.rectale and Bacteroides-Prevotella were quantified by FISH-FC method.After diarrhea was successfully induced,the model mice were administered with the mixture of Lactobacillus acidophilus and Lactobacillus plantarum at different amounts of 107,108,109 CFU/mL by gavage.Sterile saline was used as the control.Results: Compared with the control,the administration of the mixture containing Lactobacillus acidophilus and Lactobacillus plantarum could result in the fast recovery of disordered intestinal flora(P 0.01).The effective dose was 107 CFU/mL.Conclusion: Direct antimicrobial effect may be one of the mechanisms for regulating intestinal flora disorder.