In vitro Assessment the Potential Antioxidant and Antitumor Activities of Bifidobacterium Derived Bacteriocins

Abstract

Nowadays there are increasing interest in using microbial bioactive peptides as therapeutic agents or as adjuvant to increase the effectiveness of available therapies, a promising approach in this line is using of probiotics secreted peptides. Bifidobacterium is one of the favorite patented probiotics genera and most of human enteric Bifidobacterium secretes bacteriocins peptides to the surroundings. Bifidobacterial – associated bacteriocins are classified as GRAS peptides, and recently were attracted attention that become a widespread research topic in various fields including cancer drug discovery development. This study was conducted to seek for antioxidant and antitumor activities of bifidobacterial – derived bacteriocins. Two bacteriocins, Bifidin B1 and Bifidin B2, were partially purified from enteric Bifidibacterium longum Bl and Bifidobacterium bifidum B2, respectively. Bifidins were physiochemically characterized in respective of thermal, pH, and storage stability. Their proteinaceous nature was confirmed. Potential antioxidant activity in terms of free radical scavenging activity was evaluated, both Bifidins exhibited antioxidant activity, the highest percentage scavenging activity against DPPH was 70.55±0.2673 %, recorded for Bifidin B1, and was followed by 68.1 ±1.753% scavenging capacity for Bifidin B2, while both of Bifidins B1 and B2 had almost close values for scavenging of superoxide anion radicals, 66 ± 1.970 % and 65.64 ± 1.343%, respectively. Bifidins demonstrated potential antitumor activity on two human cancer cell lines, MCF-7 and Skov-3, however, the antiproliferative activities does not exceed 60.8%. Bifidins B1 and B2 showed highest cytotoxicity against Skov-3 cells rather than MCF-7 cells, with IC50 values of 28.9± 8.76 µg/ml, and 29.87± 9.13 µg/ml, respectively.