Keratinase is a protease which degrades the insoluble protein keratin that is largely found in feather waste. Fifty-seven soil samples were collected from a feather and poultry waste dumping sites. All these soil samples were subjected for enrichment in Whole feather meal medium containing 1% chicken feather as a sole source of Carbon, nitrogen and energy with pH 8.0 and incubated at 30°C on shaker condition (150 rpm) for 7 days. Out of 57 flasks only 21 showed visual feather degradation. Enriched sample from each flask was isolated on skimmed milk agar plates. Only 10 isolates demonstrated proteolytic activity by showing zone of clearance around the colony on skimmed milk agar medium. The above 10 bacterial isolates (Kar:01-12) were assayed for keratinase enzyme by growing them in Whole feather meal medium pH 8. Maximum keratinase production was demonstrated by isolate number Kar05 (41U/ml) at 30°C on shaker condition (150rpm) after 4 days of incubation. Promising isolate was identified as Stenotrophomonasmaltophila KARUNA5 by morphological, cultural, biochemical and 16S rRNA sequence analysis and was submitted to NCBI (Accession no: LC271188).
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