ANTIMICROBIAL AND ENZYME ACTIVITY PRODUCED BY BACILLUS SPP. ISOLATED FROM SOIL

摘要

Objective: Our study was to isolate Bacillus spp. from soil all around 6 geographic parts of Thailand and screen for potential antimicrobial. Methods: A total of 43 isolates which isolated from 100 samples of soil were investigated. Preliminary screening was based on antimicrobial activity against 16 strains of pathogenic bacteria and fungi, including 10 strains of Methicillin-resistant Staphylococcus aureus (MRSA), and 1 strain of Methicillin-sensitivity Staphylococcus aureus (MSSA), Extended spectrum beta lactamases (ESBL) Escherichia coli , Samonella Typhymurium , Klebsiella pneumoniae, Candida albicans, Cryptococcus neoformans respectively by cross streak, agar diffusion and modified microdilution technique. Moreover, the selected Bacillus spp. were then screened for bioactive enzyme, including chitinese, chitosanese, amylase, cellulose, caseinase, gelatinase, esterase and lipase production of different selective media for 24 and 48 h by direct spot agar. Results: There are 2 isolates, namely 23 and 49 showed particularly strong activity inhibitions against MRSA and pathogenic C. albicans . The diameter of hydrolysis zone results from screened for bioactive enzyme revealed that there were 36 isolate showed particularly strong activities with a broad spectrum enzyme. The isolate which produced the widest diameter hydrolysis zone in gelatin, cellulose and starch are 294, 303, and 290 respectively. Conclusion: Our result indicated Bacillus spp. from soil in Thailand showed potent antibacterial activity and bioactive compounds production.