Abstract

A newly isolated Aspergillus awamori MTCC 9997 strain from spoiled cooked rice was cultured under solid state using cassava peel powder to produce α-amylase. The effect of extraction medium, solid to solvent ratio, extraction time, temperature and physical state on α-amylase recovery was examined. Among various organic, inorganic solvents and buffer solutions tested, maximum extraction of α-amylase was achieved when phosphate buffer of pH 7.0 was added. A solid to solvent ratio (cassava peel : phosphate buffer) of 1:10 (w/v) resulted in maximum yield of α-amylase. The optimum extraction time was 30 min. At 30°C, α-amylase recovery was found to be the maximum. An appreciable amount of α-amylase was recovered under agitated conditions of the fermented biomass at 150 rpm compared with the quantum recovered under stationary conditions.

Key words: α-Amylase, Aspergillus awamori, solid-state fermentation, extraction.