Evaluation of the probiotic potential of yeasts isolated from Indian fermented food items

Abstract

Probiotics are living microbes that are beneficial to humans. They replenish the human gut microflora after antibiotic usage and also help to fight off pathogenic microbes. Probiotics can be either natural such as curd, or synthesized, such as the Japanese drink Yakult. Most fermented Indian foods contain probiotic microorganisms, however, their properties are not well studied. In this study, different microbial isolates (8 Lactic acid bacteria and 6 yeasts) were isolated from four traditional fermented foods commonly consumed in India. Six yeast isolates were screened for different probiotic attributes. Three yeast strains were found to tolerate highly acidic conditions and bile salt concentrations of 5% and 10%. They were able to grow at 37oC and also showed cell surface-hydrophobicity and auto-aggregation ability. Two of these isolates showed production of proteases but none of them produced amylase. These isolates were also found to be resistant to ampicillin and amoxicillin. These isolates appeared to be potential probiotic candidates and need to be investigated further.