MOLECULAR ANALYSIS, DE-HAIRING ACTIVITY AND OPTIMIZATION OF PROTEASE PRODUCING BACTERIA ISOLATED FROM SOIL

Abstract

The growing demand for environmentally friendly products has encouraged industries to replace chemical formulations with microbial alternatives. Among microbial enzymes, protease is one of the most commercially valuable due to its wide range of industrial applications. This study focused on the isolation, identification, and optimization of protease-producing bacteria from soil samples collected from a garden and a dairy farm at Agriculture University, Peshawar. Soil samples were serially diluted and cultured on nutrient agar. Screening for protease production was performed using skim milk agar, where clear zones indicated enzymatic activity. Out of six isolates obtained, four were from garden soil (HG-1, HG-2, HG-3, HG-4) and two from dairy soil (HD-1, HD-2). Soil pH was 8 in the garden and 7.5 in the dairy farm. Morphological and Gram staining results showed four Gram-positive and two Gram-negative isolates. The most potent protease producers were selected for molecular identification through 16S rRNA sequencing. HG-1 was identified as Acinetobacter baumannii, while HD-1 was confirmed as Pseudomonas aeruginosa. Crude enzyme extracts were partially purified and subjected to optimization studies. Maximum protease production was observed after 24 hours of incubation at pH 8 and 37 °C. The enzymes demonstrated effective feather degradation, achieving complete dehairing within seven days.