Detergent-stable amylase production by Paenibacillus lactis strain OPSA3 isolated from soil; optimization by response surface methodology

This study aimed to isolate thermostable, alkaliphilic, and detergent-tolerant amylase-producing bacteria. Pure isolates from environmental samples were screened on a starch-based medium (pH 11), and selected isolates were identified using cultural and molecular techniques. Product optimization studies were conducted, and secreted amylase was partially purified using 40% (w/v) saturation ammonium sulfate at 4 °C. The wash performance of concentrated amylase was analyzed. A novel isolate, Paenibacillus lactis OPSA3, was selected for further studies. The isolate produced amylase optimally when grown on banana peels and soybean extracts, which are agro-wastes. Optimization by Response surface Methodology resulted in a 2.1-fold increase in alkaliphilic amylase production. A 2.46-fold purification was achieved, with an enzyme activity yield of 79.53% and specific activity of 26.19 Umg⁻¹. Wash performance analysis using the amylase supplemented with boiled commercial detergent (kiln®) showed good cleaning efficiency. The amylase has the potential for application as a component of green detergent.