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Objective:To characterize the bacteriocin-like inhibitory-substances (BLIS) activity of Streptococcus macedonicus MBF10-2 [named BLIS(MBF10-2)],a bacteriocinogenic strain isolated from an Indonesian tofu byproduct. Methods:BLIS(MBF10-2) was obtained by culturing the bacterium,and standard de-ferred antagonism assays were used to demonstrate its activity. The antibacterial testing of fractions collected by filtration using 3–30 kDa cut-off membrane sizes were carried out by performing well diffusion method. Results:The growth of Micrococcus luteus,Streptococcus pyogenes,Lactococcus lactis,Leuconostoc mesenteroides and Weissella confusa were inhibited by BLIS(MBF10-2). Interestingly,BLIS-containing fractions obtained from sequential application on ultra-filtration membranes indicated that this bacterium Streptococcus macedonicus MBF10-2 could produces at least two antimicrobial peptides activities,one of which is likely to be a lantibiotic peptide. Potential synergistic activity against certain Gram-positive (but not Gram-negative) species when partnered with antibiotics (ampicillin,tetracycline or kanamycin) were observed. Conclusion:Combination of some BLIS(MBF10-2) active fractions with antibiotics (ampicillin,tetracycline or kanamycin) could demonstrate synergistic activities against certain Gram-positive species.