The strain produced a heat-stable
antimicrobial compound showing no reduction in activity
after heat treatment from 60 to 100°C for 15 and 30 min.
Since it was inactivated by proteolytic enzymes, it is considered
to be proteinaceous in nature and, therefore, referred
to as a bacteriocin-like substance. This compound was also
active over a wide pH range (pH 2–6). The antimicrobial
compound was partially purified by 40% ammonium sulfate
precipitation. Lactobacillus brevis was tested for its in vitro
antibiotics susceptibility, tolerance to bile salts, resistance to
low pH values, acidifying activity, proteolytic activity, and
haemolytic activity. The results showed the potential of L.
brevis strain as a probiotic culture, and hence it can be
utilized in the manufacturing of pharmaceuticals and dietary