A STUDY ON PARTIAL PURIFICATION AND CHARACTERIZATION OF EXTRACELLULAR ALKALINE AMYLASES FROM Bacillus megaterium BY SOLID STATE FERMENTATION

摘要

A highly alkaline amylase producing Bacillus megateriumwas isolated from enriched soilunder lab conditions. In order to enrich the soil for alkaline amylase producing Bacteria, soil was suppliedwith raw potatoes (substrate) and water at pH 10. Soil was left for 1month. After serial dilution fivedifferent colonies were obtained and were screened for amylase production. The culture MJS1105showing maximum hydrolysis zone wassubjected to solid state fermentation using wheat bran assubstrate. The enzyme was purified using ammonium sulphate precipitation followed by dialysis. Totalactivity of 7.056 Uwas obtained at 37oC after 96 hours of incubation and was found to have a molecularweight of 63KDa (approx.) by SDS – PAGE. The enzyme was relatively stable between pH 5 – pH 13and at temperature ranging from 32oC to 50oC. Moreover, activity was enhanced by using metal ions suchas Ca2+, Mg2+and Na2+. The decline in activity was observed by adding SDS and EDTA