Probiotic characterisation of Enterococcus faecalis strain isolated from a household dahi sample of Wayanad district, Kerala

Abstract

Household dahi sample with good organoleptic properties from Wayanad district of Kerala was screened for lactic acid bacteria. Gram positive cocci exhibiting potential to ferment lactose was further characterised biochemically and later identified by 16srRNA sequencing as Enterococcus faecalis. The isolate was evaluated for its physiological and probiotic properties like temperature tolerance, salt tolerance and proteolytic activity. Probiotic properties like acid tolerance, bile tolerance, adhesion potential and antimicrobial activity against clinical isolate of E. coli were evaluated. Virulence based on haemolysis in blood agar was also done. The isolate was able to survive both 4o C and 45o C as well as salt concentration of 2 to 8 per cent. This remarkably proteolytic isolate was able to survive at pH 2 and 3 for 3 h and could tolerate bile concentration of 0.3 per cent for 3 h and 0.6 per cent for 1 h. Cell surface hydrophobicity was found to be 19.6 per cent and auto aggregation 80.39 per cent. The isolate could inhibit the growth of pathogenic E.coli by producing a zone of clearance of 19mm. Antibiogram revealed resistance to Ceftriaxone, Cefotaxime, Cefazolin and Vancomycin. The isolate produced alpha haemolysis in blood agar. Study revealed that detail biochemical and molecular level characterization is required for assessing probiotic potential of lactic acid bacteria from naturally fermented products.

Comprehensive genomic analysis of hypocholesterolemic probiotic Enterococcus faecium LR13 reveals unique proteins involved in cholesterol-assimilation

“…Most of the probiotic E. faecium strains are isolated from animal/human gut and fermented foods ( 70 , 71 ). E. faecium LR13 was the first rhizospheric isolate which not only exhibited several probiotic attributes but also bile salt hydrolase activity and hypocholesterolemic activity in vitro ( 18 ).…”

Prevalence of Candida Species in ‘Thairu’ a Traditional Fermented Milk of Kerala, India

“…Lactic acid bacteria, yeast and mold and enterococci play a significant role in fermentation of traditional milks [1]. The presence of lactic acid bacteria and enterococci in traditional fermented milks of Kerala have been previously reported [2,3]. The presence of yeast and molds are considered as indicators of poor hygiene and are thus regarded as undesirable in fermented milks like dahi and yoghurt.…”