Production of alkaline protease using industrial waste effluent as low-cost fermentation substrate

The proteolytic enzymes are the most important group of commercially produced enzymes. The use of alkaline proteases has increaed remarkably in many indutrial processess. In present study, Bacillus sp. was used. Alkaline protease production under submerge fermentation using industrial waste effluent was investigated. For production of alkaline protease in a low-cost medium the waste effluent was used as the carbon and nitrogen sources. Corn steep liquor (CSL) is a byproduct of corn wet-milling. CSL is an important constituent of some growth media and was collected from Glucosan company (Alborz Ghazvin industrial town). Optimal media composition and growth conditions for alkaline protease production for Bacillus sp. were defined. The optimum conditions were pH 8, CaCl2 (1.5 g/l), yeast extract (2 g/l) and temperature (37 °C), using 5%, v/v inoculum size. Maximum enzyme activity was identified when wheat bran was used as substrate. Under this optimum condition, alkaline protease production by Bacillus sp. was found to be 100.7 U/ml.

Keywords:

Alkaline protease , Low cost substrate , Media optimization , Bacillus sp. Waste effluent