Characterization of chitinolytic bacterial strains isolated from local habitat

Chitinase enzymes have their prospective applications in agro-chemical industry, and the microbes capable of producing chitinases are being used effectively against number of soil-borne fungal pathogens and nematodes. Three potential bacterial strains were isolated from local environment to develop indigenous resources for the production of chitinases or their use as bio-control agents against plant pathogens. Following conventional biochemical tests and microscopy, these strains were preliminary identified as Serratia sp. CN-01, Serratia sp. CN-07, and Pseudomonas sp. CN-05. Chitinolytic activity was determined by incubating these strains on chitin agar plates, which showed the halo of clearing zones of average diameter of 18–23 mm. Growth conditions were characterized as increase in optical density, and fluctuation in pH of growing culture at 28 °C and 150 rpm for 72 h in a shaking incubator. Antifungal activity of these isolates was determined against the fungal pathogen Fusarium oxysporum, which showed the percentage inhibition ranging from 48% to 73% after seven days of incubation and the radii of inhibition zones varied from 11.0 to 14.7 mm. The results indicated that these bacterial isolates can be used as chitinase producing bio-agents in industry, as well as have potential to be used as effective anti-fungal agents in the field.