Analysis of Antimicrobial Activity and Extracellular Metabolites of Bacillus subtilis Strain CS16
In order to develop effective biocontrol agents,the antimicrobial activity and extracellular metabolites of Bacillus subtilis strain CS16 were analyzed.The results showed that strain CS16 had strong inhibition against many pathogenic fungi but rather weak in anti-bacterial activities.The activities of carboxymethyl cellulase,amylase and xylanase in fermented liquid of CS16 were 509.58 U/mL,7198.71 U/mL and 1853.68 U/mL,respectively.The crude extract of the fermented liquid from strain CS16 had distinct inhibition against Fusarium oxysporum f.sp.cubense and its minimal inhibitory concentration(MIC)was 0.062 5 mg/mL.And then the extract was purified by reverse-phase silica gel column,sephadex LH-20 gel column and normal-phase silica gel column.The antimicrobial substance in the purified extract was Iturin A by thin-layer chromatography and HPLC analysis.