The antibacterial activity of partially purified bacteriocin produced by lactic acid bacteria isolated from raw goat’s milk was assessed and characterized. From thirty isolated strains, the produced bacteriocin by Pediococcus acidilacticci (BL20)and Streptococcus thermophilus (BL16) has manifested a maximum antibacterial activity against the investigated Bacillus cereus and Staphylococcus aureus ATCC 25932. The investigation of the produced bacteriocin by Pediococcus acidilacticci (BL20) indicated their stability after heat treatment, whereas, the activity of the produced bacteriocin by Streptococcus thermophilus (BL16) was decreased after the heating and completely inhibited at 121°C. The maximum antibacterial activity of the both produced bacteriocins was obtained by pH range of 4-7 and affected by the adding of trypsine. The produced bacteriocins by the selected producing bacteria were observed in the early logarithmic growth phase. Furthermore, the investigated produced bacteriocins on the bacterial growth indicated two mechanisms effect, which has manifested a bacteriostatic by Staphylococcus aureus ATCC 25932 and bactericidial by Pediococcus acidilacticci BL 20.The technological properties and the stability of bacteriocins may lead for application as biopreservative agents to control pathogens and spoiling bacteria in different food products.
