Isolation and Characterization of Keratinase Producing Organisms from Fish Scale Dumpsite at Gusau Dam, Gusau, Zamfara State, Nigeria

The global fishing industry, a vital source of food and economic activity, generates substantial amounts of fish scale waste, a byproduct of fish processing that poses significant environmental challenges. This waste, often discarded in landfills, contributes to environmental pollution and the depletion of valuable resources, particularly keratin, a protein with diverse industrial applications. Microbial bioconversion of the rich keratinous waste abundant in the environment provides a rich source of available protein which lurks in keratin-rich waste and this achievement will lead to a reduction in environmental pollution and improve the economy as the proteins gotten and microorganisms isolated can be utilized in the production of high-value products in both agriculture, pharmaceutical, cosmetics, detergent, textile, fertilizer, and biomedical industries. This study aimed to isolate keratinase-producing organisms from decaying fish scales. The research commenced by enriching decayed fish scales in a basal medium, followed by inoculation onto three different media: Fish Scale Agar (FSA), Starch Casein Agar (SCA), and Nutrient Agar (NA). This resulted in the isolation of 27 bacterial strains, they were subjected to proteolytic enzyme activity analysis on skim milk agar to identify the proteolytic organisms and six (6) isolates namely SCAA1 (2cm), SCAA2 (1.3cm), SCAA3 (4cm), SCAA4 (4.2cm), FSAA2 (2.4cm) and FSAA5 (2.2cm) showed hallow zones of different magnitude on skim milk agar. FSAA2 (68%) and SCAA1 (66%) showed highest levels of degradation of whole fish scales and these two isolates were identified as Alcaligenes faecalis (SCA A1) and Pseudomonas aeruginosa (FSA A2) using a combination of Gram’s reaction, biochemical tests, and 16S rRNA gene sequencing.