Volume: 57 Issue: 3
Year: 2026, Page: 486-490, Doi: https://doi.org/10.51966/jvas.2026.57.3.486-490
Received: May 2, 2026 Accepted: Aug. 7, 2026 Published: Sept. 30, 2026
The present study aimed to investigate the presence of Bacillus spp. in chicken waste dumping sites and poultry farms in the Thrissur district to produce extracellular protease. Thirty soil samples were collected from chicken waste disposal sites, as well as from poultry farms and analyzed for physicochemical parameters, soil type, and the presence of Bacillus spp. Out of the 68 isolates from 30 heat-treated soil samples, 26 Bacillus isolates were identified using standard microbiological methods and confirmed by polymerase chain reaction targeting 16S rRNA. All 26 Bacillus isolates were screened for extracellular protease production on skim milk agar plates, identified by the clear zone of hydrolysis around the colony. Among the 26 isolates, 18 Bacillus spp. were found to produce protease, accounting for a 69.2 per cent occurrence of protease enzyme-positive Bacillus spp.obtained from a total of 30 soil samples.Hence, the study suggests that skim milk agar was effective for screening extracellular protease-producing bacteria, and the aforementioned Bacillus spp. isolates demonstrated potential for protease enzyme production.
Keywords: Bacillus spp., soil, protease producer, skim milk agar, plate assay
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© 2026 Sonali et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Sonali, N,, Deepa, J., Sunil, B., Sethulekshmi, C. & Sathu, T. (2026). Extracellular protease-producing ability of Bacillus spp. isolated from chicken waste dumping sites and poultry farms in Thrissur district. Journal of Veterinary and Animal Sciences, 57(3), 486-490