Enhanced production of alkaline protease by Neocosmospora sp. N1 using custard apple seed powder as inducer and its application for stain removal and dehairing

Abstract

Alkaline proteases find extensive applications ranging from detergent industries to therapeutics due to their broad alkaline range activity. The present work describes the first report on optimization of alkaline protease production from Neocosmospora sp. N1 and explores its utility in detergent and leather industries. Wheat bran was found to be a suitable substrate for protease production under solid state fermentation amongst several low cost agro-based materials used in this study. Protease production was enhanced when wheat bran was supplemented with a novel inducer, custard apple seed powder in the ratio of 4:1 which increased enzyme production up to 1.88 fold. One factor at a time approach was used to select parameters important for production and response surface methodology was used for further optimization. The optimum level was attained at 123 h fermentation time, 63% moisture content, 1 × 10 8 spores/ml inoculum size and 1.4 mm particle size which resulted in 3.12 fold increase in protease production. The partially purified enzyme exhibited maximum activity at 60 °C and was active over a wide pH range of 8–12. Protease was compatible with various laundry detergents viz . Tide, Surf Excel, Ariel, Wheel etc. showing more than 80% stability even after 3 h of incubation and was efficient in removing blood stain from the cotton cloth. The enzyme was also more efficient in dehairing goat skin as compared to conventional leather processing treatment. • Statistical optimization of alkaline protease production in SSF from Neocosmospora species is studied. • The protease production increased 1.88 fold by use of custard apple seed powder as a novel inducer. • 3.12 fold enhancement in protease production was achieved by using Box-Behnken Design. • Neocosmospora sp. alkaline protease is efficient in removing blood stains having 80% compatibility with commercial detergents. • Protease produced cleaner, whiter, smoother skin as compared to sulphide treatment.