Survey for Tyrosinase production by Streptomyces species

Abstract

The present study was focused on isolation and screening of tyrosinase enzyme produced by actinomycetes. The isolates were primarily identified to genus level on the basis of their microscopic and cultural characteristics. Biochemical and other characters were used to identify isolates to species level. A total five soil samples were collected from different sites at Damietta EL-Gededa (Egypt) and Meslatah (Libya). The total 36actinomycete isolates were obtained from soil by performing serial dilution technique and using starch-nitrate agar and primary screened for tyrosinase production by using tyrosine agar medium. Based on the result of primary screening,8 isolates 2D, 4D, 5L, 6L, 12D, 13D, 14D and 26L showed blackish brown pigment development due to melanin production, was selected. These isolates were taken for secondary screening(tyrosinase assay) by culturing on tyrosine broth at 30 O C for 5 days. Greenish black color was reported in tyrosine broth indicated the positive tyrosinase activity. Out of them, isolates13D,14D and 26Lwhich showed the highest tyrosinase activities (1.2 U/ml, 4.8 U/mL and 8.4 U/mL, respectively) were identified on the basis ofcultural, morphological, physiological, biochemical as Streptomyces malachitorectus, Streptomycesiakyrus and Streptomycesechinatus, respectively.