Abstract

OPTIMUM CONDITIONS FOR L-ASPARGINASE PRODUCTION BY LOCAL ISOLATE OF PSEUDOMONAS AERUGINOSA P4

Elaf I. Alkhassaki* and Asmaa A. Hussein

Abstract

In this study, a total of forty six samples were collected for isolation of P. aeruginosa. These include 14 samples taken from wounds, 20 samples of burns and 12 samples of ear infections collected from Alyarmouk hospital. From these samples, a total of 29 bacterial isolates were obtained .when subjected to morphological and microscopical tests. L-asparginase enzyme activity was determined by quantitative methods using L-aspargine as substrate for these isolates, results indicated that 6 isolates of them are l-asparginase producer with different specific activity ranged between (0.02-0.15) U/mg and the isolate Pseudomonas aeruginosa P5 was the most efficient in the production of l-asparginase with specific activity of 0.15 U/mg protein therefore, it was chosen to determine the optimum conditions for l-asparginase production. Maximum lasparginase production was achieved after supplementation of the minimal salt medium (pH7) with 0.1% glycerol, 0.1% tryptone and incubated at 37oC in shaker incubator (150 rpm) for 24h. Under these conditions, the specific activity of l-asparginase produced in culture supernatant was sharply increased to 0.6 U/mg protein.

Keywords: L-asparginase, Pseudomonas aeruginosa, l-asparginase activity, optimization.