Recovery of Lactobacillus casei strain Shirota (LcS) from faeces of healthy Singapore adults after intake of fermented milk

Abstract

To validate survival of Lactobacillus casei strain Shirota (LcS) during passage through the gastrointestinal tract of healthy Singaporean young adults, 21 participants (18-25 years old) were asked to consume a 100 ml of fermented milk drink containing 1.0×108 cfu/ml of LcS daily for 14 days, and to maintain their dietary habit and life style. During and at the end of the ingestion period, both culture method (identity confirmed by ELISA) and 16s rRNA sequencing results revealed that viable LcS (7.27 and 7.64 log10 cfu/g of faeces at the ingestion period Day 7 and Day 14, respectively) and Lactobacillus could be recovered from the faeces of all the subjects. The viable LcS count from male and female were comparable for each time point. Before consumption (baseline) and 14 days after cessation of consumption of the fermented milk, LcS was not detected in most of the subjects. In this study condition, the composition of the major gut microbiota (>0.1% in relative abundance of genus) and characteristics of defaecation such as stool consistency and frequency of defecation did not change throughout the study before and after ingestion of LcS. LcS was able to survive passage through the gastrointestinal tract of Singapore adults without sustainable colonisation, but the effect of LcS on microbiota modulation, stool consistency and frequency was not observed under this study condition.

Gut Microbiome of a Multiethnic Community Possessed No Predominant Microbiota

“…This demonstrates that persistence and colonisation of the exogenous Lactobacillus in the gastrointestinal tract of Singapore young adults are basal microbiome and diet dependent. This agrees with our earlier studies [25,26].…”

A critical evaluation of the factors affecting the survival and persistence of beneficial bacteria in healthy adults

“…2. Recovery amount higher than 10 5 cfu/g (Ahmed et al, 2007;Alander et al, 1999;Dommels et al, 2009;Hanifi et al, 2015;Khine et al, 2019;Lund et al, 2002;Rattanaprasert et al, 2014;Saxelin et al, 1995;Vesa et al, 2000).…”

“…Jacobsen et al (1999) and Klingberg and Budde (2006) used strain-specific Internal Transcribed Spacer region (ITS)-PCR and restriction enzyme analysis followed by pulsed-field gel electrophoresis to identify the probiotic strains they isolated in their studies. Khine et al (2019) used a strain-specific monoclonal antibody in an enzyme-linked immunosorbent assay (ELISA) to detect Lactobacillus casei Shirota. Van Bokhorst- Van de Veen et al (2012) amplified and sequenced a variable intergenic region to distinguish between the probiotic strains isolated from faeces samples.…”

Colonization Ability and Impact on Human Gut Microbiota of Foodborne Microbes From Traditional or Probiotic-Added Fermented Foods: A Systematic Review

“…As regard to other bacterial group modifications, heterogeneous results were reported (31,37). Finally, no significant changes in gut microbiota composition were observed in two studies (36,38).…”

“…Moreover, some of the studies revealed the presence of live LcS by culture-dependent methods followed by further, specific molecular analysis to confirm LcS identity (32,40,41). Interestingly, all studies where persistence was evaluated (n = 6) (32,36,(40)(41)(42)(43) demonstrated that no LcS could be detected in volunteer stool samples when tested at various time points (ranging from 1 week to 6 months of post-intervention washout) after completion of the study, except in very rare cases (32,36), further suggesting that regular consumption is required for persistence of ingested probiotic strains in the gut.…”