Isolation Of Aeromonas Sp.CJ-5 Producing Both Chitinase And Chitosanase As Well As Analysis Of The Fermentation Condition And Enzyme Property

A strain CJ-5 producing both chitinase and chitosanase was isolated from soil samples of Zhejiang province. It was identified as Aeromonas sp.. The optimal fermentation condition for CJ-5 strain to produce chitinase was incubated in flask at 30℃, with 20% medium (initial pH7.0) containing 2.5%(w/v) chitin, while that of producing chitosanase was incubated at 30℃ in flask with 25% medium (initial pH6.0) containing 2.5%(w/v) chitosan. The highest chitinase and chitosanase activity were 0.41U/mL and 1.5 U/mL when CJ-5 strain was incubated on chitin medium in 3L fermentor. The crude enzymes were obtained from the fermentation broth by ammonium sulfate precipitation. The optimal pH temperature were 7.0 and 36℃ for hydrolysis of chitinase as well as 7.0 and 56℃ for hydrolysis of chitosanase. The stability of chitinase and chitosanase rapidly decreased above 50 ℃. By SDS-PAGE and PAGE analysis, the molecular weights of the chitinase and chitosanase were 250 kD and 50 kD, respectively. The fermentation broth of chitin-degrading exhibited antimicrobial activity evidently and growth-stimulated of Oryza saliva seedings to a certain extent.