Carbon sources: The effects of various carbon sources (5 g L-1 ) such as different monosaccharides, disaccharides and polysaccharides were tested in the absence and the presence of chitin on chitinase production.
In the control flask no carbon source was added except chitin. It was formd that chitin was the best carbon source for chitinase production by Aeromonas sp. JKl. In a medium lacking chitin, no chitinase production was observed. However, when xylan and pectin included in the medium chitinase activity was detected to some degree. Addition of chitin increased the chitinase production after 24 h. The maximum peak of activity was observed near 72 h, after that the chitinase activity decreased slowly. These carbon sources in the presence of 5 g L-l chitin caused no enhancement of chitinase production compare to the control. To optimize chitin concentration (as the main carbon source), different concentrations (1.25 to 30 g L-1) were used in the production medium and maximum chitinase production by Aeromonas sp. JKl was formd in a media with 7.5 g L-l chitin (Fig. 1).