SCREENING AND BIO-CHEMICAL CHARACTERIZATION OF PROTEASE PRODUCER ESCHERICHIA COLI AND INDUSTRIAL APPLICATION IN PLASTIC DEGRADATION

J. Ntuilula Rangnamei*, Thatipamula Tejasri, Aishwarya and Vinod Kumar Gupta

ABSTRACT

A protease enzyme was produced from Escherichia coli that was isolated from sewage water and was biochemically identified and studied. To induce the protease enzyme, E.coli was grown in a shake flask containing tryptic soy broth. Ammonium sulphate precipitation served to partly purify the protease enzyme. The ability of the bacteria to produce protease enzyme was screened on skim milk plate agar, and the pH, temperature, and incubation time were optimised to determine the enzyme's maximal output. The purified protease has the maximum activity at pH 6, with an inoculum concentration of 1.5108 CFU/ml at 37°C after 24 hours of continuous agitation at 150 rpm, the protease enzyme is commercially exploitable. Additionally, E.coli bacteria are used in degrading polythene and plastic bottles. The biodegradation of plastic polythene and plastic bottles was analysed after 15 and 30 days of incubation in nutrient broth, respectively. Comparatively, more polythene is used than plastic bottles degraded by biodegradation. In a month, the degradation of plastic polythene increased to 4.08% and that of plastic bottles to 1.02%.

Keywords: E. coli, Optimisation, Plastic, Polythene, Protease, Sewage.