Harnessing amylase producing novel bacterial strains from industrial waste: A bioprocessing and optimization approach

Enzymes are increasingly in demand across various industries due to their emerging applications in promoting sustainable, eco-friendly, and economically viable processes. This research investigated the production of an industrially important enzyme, amylase, to explore its potential applications. Two amylase-producing bacterial species were isolated from soil and potato-processing waste (PPW). Molecular identification of the isolates was done via 16S rRNA sequencing, and they were identified as Klebsiella pasteurii NITTBP2 and Bacillus clarus NITTBP1. One variable at a time (OVAT) analysis concluded that B. clarus showed higher crude amylase specific activity (136.15 U/mg) than K. pasteurii (7.69 U/mg). Response Surface Methodology (RSM) was employed to study the effects of process parameters for B. clarus, and the maximum crude amylase specific activity achieved was 139.23 U/mg with the amylase activity 18.10 U/mL at 35 °C, pH 8, and starch of 7 g/L. The production potential of crude amylase showed ~5 × 10⁵ to 6 × 10⁵ U/mL per kg of PPW using B. clarus. The study outcomes emphasize using robust and unexplored B. clarus and its ability to produce industrial enzyme amylase. It also provides the opportunity to utilize the PPW starch for large-scale sustainable enzyme production.