Abstract:The activities and components of extracellular metabolites of a mutant Bacillus SC27 which was isolated from mangrove soil and was mutated via combined nitrosoguanidine (NTG) and UV were analyzed. The results showed that the Bacillus SC27 produced lactic acid of 5.04 g/L. The activities of protease, amylase, cellulase in the fermentation fluid were 1 316.59 U/mL, 176.2 U/mL and 513.3 U/mL, respectively, while no lipase activity was detected. The extracellular metabolic products showed higher anti-bacteria activities against Gram-positive bacteria than those against Gram-negative bacteria, and the anti-bacterial products of Bacillus SC27 could withstand treatment of high temperature, enzymes of papain, proteinase K and trypsin. Main chemical compositions of fermentation fluid extracted by dichloromethane were hydroxytoluene of 10.28%, dimethoxydimethylsilane of 7.87%, 2,4-bis(1,1-dimethylethyl)-phenol of 2.92% and 2 unidentified compounds of 4.47% and 2.36%.