Optimization and Production of -Amylase from Halophilic Bacillus Species Isolated from Mangrove Soil Sources

摘要

In the present study, four bacterial isolates from a mangrove soil were screened for their ability to produce α-amylase using submerged fermentation. Bacillus MJK1, MJK2, MJK6 and MJK10 which were assigned to be Bacillus species proved to be the best α- amylase producer. Various effects of pH, temperature, incubation time, carbon source and salinity were checked. Different carbon supplements were used to enhance the enzyme production and the highest yield was obtained with 2% soluble starch as supplements. The presence of fructose, maltose, sucrose, glucose reduced the production of amylase. The optimum pH, temperature, and incubation period for amylase production by the isolate was found to be 8.0, 50°C and 72 hrs respectively. The production medium with increase in addition of NaCl, diminished the production of amylase. The presence of NaCl in the culture media promoted extracellular amylase even in the presence of 4% NaCl.