Intestinal Microbiota in Stool of Thai Healthy Volunteers and Their Drug Resistant Extended Spectrum β-Lactamase (ESBL) and Ciprofloxacin-Resistant (CIP-R) E.Coli Before and After Ingestion of Fermented Milk Containing Lactobacillus Casei Strain Shirota (Lcs)

Objective: To identify the spectrum of microbiota from stools of Thai volunteers before, during and after administration of fermented milk containing LcS and to see if there is any change in the spectrum of microbiota and the concentration of their extended spectrum beta-lactamase (ESBL+) E. coli and ciprofloxacin-resistant (CIPR) E. coli. Material and Methods: Stool samples were collected from the 20 healthy adult volunteers before and 7 days after taking LcS containing milk product (follow-up period) for 7 days. Stools were analysed for the spectrum of microbiota using YIF-SCAN® PCR for stool organic acids content using HPLC technique and were cultured for entero-pathogenic bacteria using MacConkey agar, TCBS agar and XLD agar. The cultured E. coli were analysed for ESBL-production and CIP-R production by double disc method. Results: The concentration of Lactobacillus, especially the L. casei subgroup was increased during the LcS ingestion period and decreased after stopping LcS. The concentration of Bifidobacterium and acetic acid were significant higher in the LcS ingestion period than baseline period. There was 45% (9/20) of subjects carried ESBL and/or CIP-R E.coli at baseline. It was observed that in some cases, there was absence of ESBL-producing E. coli and less CIP-R E.coli during the LcS ingestion period. In these cases, the re-appearance of ESBL-producing E.coli and CIP-R E.coli was observed in the follow-up period which LcS ingestion was stopped. Conclusion: There were some changes in the spectrum of microbiota, short chain fatty acids and the patterns of E. coli antibiotic resistant before, during and after ingestion of L. casei, but the consistency of findings needs to be further studied.