Lactic acid bacteria are Generally Regarded As Safe (GRAS) and have long been used as natural biopreservatives. Lactic acid bacterial cultures were isolated from different fermented food samples viz., cumbu gruel, cold rice, milk fermented by green chilli, palmyrah fruit, mango pickle, sauerkraut and fermented finger millet and neera. They were screened for their antimicrobial activity against common food borne pathogens viz., Staphylococcus aureus, Pseudomonas aeruginosa and E.coli and spoilage organisms from spoiled potato, papaya, intestine of goat and hen and fish waste. Among the isolated cultures, cultures from cumbu gruel (CS and CT) exhibited the maximum antimicrobial activity. Out of twenty six fractions eluted for CS and CT, only three viz., CT-5, CT-7 and CS-2 exhibited maximum antimicrobial activity. These three fractions were further analysed in HPLC which distinguished CT-7 fraction with a discrete and unique peak. GC-MS analysis was done for this particular fraction of CT-7 and the compound was identified as hexadecanoic acid, methyl ester. 16S rRNA partial gene sequencing identified CS culture as Streptococcus thermophilus and CT culture as Lactobacillus coryniformis. Bioefficacy testing of CT metabolite showed that CT and CT+CS treated samples of papaya, raw fish, raw meat did not exhibit any spoilage. After 40 days, the potatoes started sprouting in the untreated control whereas potatoes treated with CT and CS+CT did not show any symptoms of sprouting and softening. The study concluded CT culture from fermented cumbu gruel as a potential candidate with antimicrobial activity against common food pathogens and food spoilage organisms, and could be effectively used as a food biopreservative for extended shelf life of foods.