Isolation of probiotic lactococcus from milk and milk powder by serial dilution spread plate method to study antimicrobial activity.

The main aim of our study is to isolate and identify the probiotic organisms and to study the antimicrobial activity of the organisms. Lactic acid bacteria from various milk sources were isolated by the serial dilution spread plate method. Raw milk and Milk powder was taken as source material for isolating LAB. Inoculation of the bacteria was done and After the inoculation, the plates are incubated at 37℃ for 24 to 48 hrs in the incubator in an inverted position for detecting growth of organisms in the form of a single colony. 2 groups with 20 samples per group were analysed by keeping threshold 0.05 and G power 80% coincidence interval 95% and enrollment ratio as 1. Compared to powder milk (3x10⁵) maximum colonies were recorded in raw milk (31x10⁵). The significance was found p<0.0001 in paired t-test. Antimicrobial activity is done with the biofilm degradation and it was found 28% effective against Pseudomonas biofilms as well as 51% effectiveness was detected in Staphylococcus biofilms degradation. of the probiotic Lactococcus from milk and milk powder with antimicrobial activity was done by serial dilution spread plate method. [ABSTRACT FROM AUTHOR]