An inexpensive substrate for the production of alkaline protease by Bacillus sp and its application studies of Manihot esculenta

摘要

Protease executes a large variety of functions and it has many biotechnological applications. It represents as one of the third largest group of industrial enzyme and finds its applications in detergents, leather industry, pharmaceutical industry etc. Among the different vegetable waste products, peel of Manihot esculenta (Tapioca/ cassava) was used as substrates for the production of protease by Bacillus sp. The aim of our study is to utilize the waste of Tapioca peel as input for protease production using Bacillus sp. The protease produced by Bacillus sp from M. esculenta showed a pH of 10 and temperature of about 30°C. Protease produced was tested for possible industrial applications. This enzyme shows high capacity in removing the blood stain, dehairing the animal skin, digestion of natural proteins and bioprocessing of used X-ray film. The wash performance analysis of blood stains on cotton fabrics showed that blood stains were completely removed within 15 minutes of incubation of fabrics along with enzyme. Complete hair removal of goat skin by the protease achieved within 12 hours of incubation at 30°C. This enzyme has the ability to dissolve the blood clot and coagulated egg within 20 minutes of incubation. Enymatic hydrolysis of gelatin from waste X-ray films was also investigated. At the end of the treatment, gelatin layer was completely removed leaving the polyester film clean. Gelatin hydrolysis was monitored by measuring increase in turbidity. Gelatin layer was removed completely within 10 minutes of addition of enzyme. The protease produced exhibits high antibacterial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The present study was a humble attempt towards the production of protease and to check their efficiency in industrial applications. These properties indicate the possibilities of enzyme usage in various industries and it can be exploited commercially in future.