Molecular characterisation of probiotic lactobacillus fermentum isolated from home made curd

32 lactic acid bacterial isolates were screened from homemade curd collected from various regions of chittoor district, Andhra Pradesh,
India. Most of the bacterial isolates were found to be gram positive, catalase negative and were preliminarily evaluated for their
probiotic potential like acid tolerance, bile tolerance, thermo tolerance, osmo tolerance and antibiotic susceptibility. Among all the 32
isolates, 9 isolates viz. L1, L2, L3, L4, L5, L6, L7, L8, and L9 were found to be having promising probiotic activity were further screened for
antagonism against enteropathogens. One of the isolate (Lactobacillus spp L2) with significant probiotic properties, antagonistic activity
was characterized by 16S rRNA sequence analysis and was identified as Lactobacillus fermentum. The bacteriocin produced by
Lactobacillus fermentum was purified by a process of ammonium sulfate precipitation and chromatography techniques. The study
revealed the possibility of using bacteriocin as a food preservative and the Lactobacillus fermentum strain as probiotic.