Microbiological analysis of Lactic Acid Bacteria (LAB) in naturally fermented Carica Papaya (CP) leaves

The present study reported on microbiological analysis of the natural fermentation of fresh CP leaves that involved isolation and cultivation of the microbes, colony counting, pH and gram staining. The microbes from naturally fermented CP leaves were isolated and cultivated on nutrient and MRS agars. The selective MRS agar used to cultivate LAB as suspected dominant bacteria which played preservative role during fermentation. Serial dilution method was used to ease the determination of number of colony presence on agar medium at different fermentation stages. The bio-preservative role of LAB was analysed through pH and its growth (colony counts). Low pH around 4.67 to 3.64 detected along fermentation process hinted the presence of LAB which inhibited the growth of other pathogenic bacteria. Gram staining results which indicated the presence of gram-positive bacteria further supported the hypothesis on the presence of LAB while colony counts on MRS medium recorded high number (between 4 to 10 million CFU/ml) These findings inferred the significant presence of LAB which could play preservative role in naturally fermented CP leaves.