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Marine bacteria are the enormous source of bio-controlling agents.On the basis of broad spectrum antimicrobial activity against both Gram-Positive and Gram-Negative food pathogens,among 230 marine bacterial isolates,DK1-SA11 were selected and identified by microscopic characterization,API 50 CH carbohydrates utilization and 16s rRNA gene sequencing as Bacillus sp.( NCBI GenBank:JX391980).Phylogeny and basic local alignment search tool (BLAST) reveal that this strain was isolated and reported first time.Antimicrobial spectrum of cell free extract (CFE) shows activity against all tested bacteria including Staph aureus,E.coli,methicillin resistant Staph aureus (MRSA),E.coli O157:H7,Listeria monocytogenes, Vibrio parahaemolyticus, Vibrio cholerae,Salmonella typhi,Klebsiella pneumonia and Pseudomonas fluorescens.Among 13 growth mediums,2216E marine broth was found to be best medium for bacterial growth and antibacterial compound(s) production.Moreover pH-7,Incubation temperature 25 ℃ with 180 rpm agitation for 48-60 h was optimized conditions.DK1-SA11 can grows and show antibacterial activity in minimal medium with glucose,maltose,sucrose and starch as carbon source.Furthermore Isolate can tolerate up to 8% NaCl in 2216E broth.Out of 49 different carbohydrates D-mannose increases the antibacterial compound(s) activity by 33.3% and D-arabitol decreases antimicrobial activity by 44.4%.Cold storage below -20 ℃ of crude CFE shows activity even after three months,whereas CFE was 100% active at 100 ℃ after 10 min and 52% activity were found after 60 min.Salt (NaCl) concentration up to 2 % increases activity and remains at 6 %.CFE shows 100% lost of activity after lipase,trypsin and papain enzymatic treatments and partial loss after papsin & proteinase K treatments,although no change in activity against test strains after ∞-amylase treatment.Freeze dried CFE shows stable activity in buffer range of pH 2-13.Out of 11 different solvent with different polarity diethyl ether were found to be best solvent for active compound extraction from CFE.Bacillus sp.DK1-SA11 may be use as best source for the application in food industries as bio-controlling agent,probiotic and its compound purification may lead to application of broad spectrum antimicrobial agent as food preservative.