Abstract:

The present investigation aims to isolate and identify chitinase producing mycoflora and the chitinase production by efficient Aspergillus terreus on different shell powder wastes substrates such as prawn, crab and molluscs at an extracellular and intracellular level and its efficacy in assessing the antifungal activity. Shell fish wastes disposed soil samples were collected and screened for chitinolytic fungi (hydrolyzing zone). The chitinase production on different substrates was assessed and the enzyme extracts were screened for antifungal activity by agar well and disc diffusion methods. Among the number of mycoflora isolated only 4 fungal strains Aspergillus terreus, A. fumigatus, A. flavus, and A. clavatus showed maximum hydrolyzing zones. A significantly highest hydrolyzing zone (clearance zone) of 20 mm (out of colony diameter of 65 mm) was obtained by Aspergillus terreus. Among the different substrates (prawn, crab and molluscs shell powders at 1% concentration), highest chitinase activity was recorded by Aspergillus terreus on prawn shell powder waste followed by crab shell powder waste at an intra and extra cellular level. The chitinase produced from prawn shell powder waste as substrates by A. terreus showed maximum zone of inhibition in both agar well (28.0 mm) and disc diffusion (24.0 mm) methods against the pathogenic fungi, A. flavus compared to positive control (Fluconazole). The chitinase produced from A. terreus might have synthesized some antifungal compounds which may be responsible for killing pathogenic fungi.

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