The aim of this research was to isolate lactic acid bacterial (LAB) strains, characterize them and classify the bacteriocin
producing LAB strain from indigenous dairy sources. Antimicrobial potential of LAB strain was tested against L.
monocytogens. The antimicrobial compound was also tested for maintaining the decreased colony forming unit (CFU) for
minimally processed vegetables like carrots, cabbage and lettuce in second phase of the research. The initial identification was
based on conventional morphological and biochemical analysis while the final confirmation was done by utilizing advanced
molecular tools. Prior to all these manipulations the growth conditions were carefully optimized for the respective strains. The
study finally led us to conclude that Lactococcus lactis subsp. lactis was the most abundant type of lactic acid bacteria found
in indigenous dairy products (sour cream and cheese) samples studied. A bacteriocin (Lacticin SC07) produced during the
growth of Lactococcus lactis subsp. lactis was purified partially by using biochemical technique ammonium sulfate
precipitation in different percentages (60% and 80%). These precipitations lead to a 437-fold increase in total lacticin SC07
activity. SDS-PAGE electrophoretic pattern of lacticin showed that it is a single peptide band of 1.7 kDa. But, 3.7 kDa dimers
also showing lacticin SC07 activity. The findings of my research revealed that the isolated LAB strain has good potential for
bacteriocin production and antimicrobial potential that exerts in the usage of this bacteriocin (lacticinSC07) as a natural
preservative in minimally processed vegetable industry.
Azam Shakeel, Muhammad Saeed, Muhammad Atif Randhawa, Muhammad Anjum Zia. (2018) ISOLATION AND CHARACTERIZATION OF BACTERIOCINOGENIC LACTIC ACID BACTERIA FROM INDIGINOUS DAIRY SOURCE AND ITS ANTIMICROBIAL POTENTIAL, , Volume 55, Issue 1.
