Production and partial purification of α-amylase from Pseudomonas sp. 2 under solid-state fermentation

Abstract

th Main, ABSTRACT Purpose: The purpose of the present study was to isolate Pseudomonas sp. 2 from rhizosphere and screen for best amylase producer and to check for its suitability for industrial applications. Methods: Four strains of Pseudomonas were isolated from rhizosphere soil, by serial dilution method, of which Pseudomonas sp. 2 gave best results to α-amylase production. This strain was used to determine the enzyme production by SSF on wheat bran. Results and conclusion: The optimal enzyme production was obtained at 37 oC and pH 7.5. Vitamins B12 (50 mg) followed by Pyridoxine (50 mg) were found to be enhancing the enzyme production. Amino acids cysteine (30 mg), tyrosine (40 mg) and alanine (30 mg) were stimulating the enzyme production. The enzyme was partially purified by ammonium sulphate precipitation, and was further purified by ion exchange DEAE-cellulose column Chromatography. The purity of the enzyme was 45.2 fold greater than the crude enzyme. The molecular weight of the enzyme was found to be ~62 kDa by SDS-PAGE. This is the first report of any Pseudomonas sp. from rhizosphere being used for amylase production. The purified enzyme was not thermostable but it was acid tolerant making it suitable for industrial application.