Exrtacellular enzyme activity and antimicrobial activity of culturable bacteria isolated from soil of Grove Mountains，East Antarctica

Abstract:

Abstract:［Objective］To investigate the composition of culturable bacteria from soil of Grove Mountains，East Antarctica and analyze the production of extracellular hydrolytic enzymes and antibacterial and antifugal activities of these culturable bacteria.［Methods］We used spread plate method to obtain culturable bacteria.Phylogenetic relationship was analysed based on their 16S rRNA gene sequences. We used plate method and agar block method to detect the production of extracellular enzymes and antibacterial and antifungal activities of these bacteria，separately．［Results］We obtained a total of 39 isolates from all the soil samples. They belonged to 20 genera and grouped into Firmicutes，Proteobacteria，Actinobacteria，Bacteroidetes，Deinococcus-Thermus lineages，of which each group occupied 48.7%，25.6%，20.5%，2.6%，2.6% of the total，respectively．Bacillus was dominant．We isolated different strains from soil stored at different temperatures，and this may be explained as viable bacteria were different at diverse temperatures．Of the 39 isolates 33 showed the activity of producing at least one extracellular enzyme．Amylase-producing strains were the most (64.1%)，6 strains were able to inhibit the growth of at least one tested bacterium or fungus.［Conclusion］Strains with extracellular enzyme activity and antibacterial and antifungal activity would contribute to the exploration of cold-active enzymes and antibacterial (antifungal) material in Antarctica．

Key words:Keywords: Grove Mountains，culturable bacteria，isolation and identification，16S rRNA，extracellular enzyme，antibacterial and antifungal activity