Extracellular amylase production by Saccharomycopsis capsularis and its evaluation for starch saccharification

A strain of starch-assimilating yeast, Saccharomycopsis capsularis, isolated from Indian cereal-based fermented foods, produced significant levels of extracellular alpha-amylase and glucoamylase. The enzymes reached their peak activities during the stationary phase at the end of the 5th and 4th day of cultivation, respectively. The amylase yields were maximized by a proper choice of carbon and nitrogen sources, starting pH of the culture medium and growth temperature. High activities of the enzymes were obtained through inexpensive agricultural commodities, such as wheat bran and corn meal as carbon sources, and defatted soybean meal and peanut meal as nitrogen sources. A temperature of 28-32 degrees C and an initial pH of 4.5-5.0 were optimum. The crude amylase mixture could liquefy and saccharify a 1% starch solution completely in 24 h at 50 degrees C.