Isolation and molecular identification of two chitinase producing bacteria from marine shrimp shell wastes

Abstract

Background and Objective: Chitinase enzymes have a various application in the field of environmental, biotechnology and medical aspects. This study aimed to the production of the chitinolytic enzymes from different species of bacteria. Materials and Methods: Bacterial isolation from different habitats was carried out on agar medium containing chitin as carbon and nitrogen sources. The obtained bacteria (20) were characterized and screened again in chitin broth medium. Results: Out of 20 bacterial isolate, 2 new isolates, belonged to Streptomyces laurentii SN5 and Cellulosimicrobium funkei SN20, were the most active in chitin degradation compared to the other isolates. They have been characterized for the first time for their chitinase activity. They were identified using 16S rRNA gene analysis and in the liquid medium, the 2 isolates have enzyme activities of 0.533 and 0.537 U mLG1, respectively. The maximum chitinase production was obtained when those bacterial strains were grown in Luria-Bertani (LB) broth amended with 1% colloidal chitin, for 1 day and at temperature of 30EC. The optimum pH value for chitinase production was pH 7 for both S. laurentii and C. funkei. The enzyme has been purified using Sephadex G-100 and DEAE-Cellulose chromatography column and found to have a similar molecular size of ~50 kDa. Conclusion: Those two bacterial species could be used in chitinase production and in the environmental recycling of disposable chitin wastes such as chitin from shrimp shell waste.