Abstract:
A bioactive peptide of 8595 Da was purified from the cell free supernatant of
Lactococcus garvieae subsp. bovis BSN307T
. MALDI MS/MS peptide mapping
and the data base search displayed no significant similarity to any reported
antimicrobial peptide of LAB. This peptide at a dose concentration of
200 µg ml−1 inhibited the growth of both Gram-positive and Gram-negative
bacteria by 58–89% and a dose of 500 µg ml−1 scavenged 50% of DPPH-free
radicals generated. Interestingly, cytotoxicity assay demonstrated that
17 µg ml−1 of peptide selectively inhibited 50% proliferation of mammalian
cancer cell lines HeLa and MCF-7 whereas normal H9c2 cells remained
unaffected. Fluorescent microscopic analysis after DAPI nuclear staining of
HeLa cells showed characteristics of apoptosis and activation of caspase-3 was
ascertained by caspase-3 fluorescence assay.
