Aradhana Satapathy, Gagan Kumar Panigrahi
Proteases, also referred to as proteinases or peptidases, are a collection of hydrolase enzymes responsible for cleaving peptide bonds in proteins. They are broadly classified as endo-peptidase which act within peptide chains, and exo-peptidase which sequentially remove amino acids from the terminal ends. Microbial proteases, particularly alkaline proteases are essential for various bio-industrial applications, including pharmaceuticals, biotechnology, detergent formulations, food processing, waste management, and the production of bioactive peptides and environmental sustainability. The expanding scope of microbial proteases in sustainable industries highlight their potential in environmental applications, particularly in bioremediation and waste management. Few studies provide a comprehensive and updated overview that integrates advanced screening techniques, latest optimization strategies, and sustainable downstream processing within a single framework. This review aims to consolidate recent advancements in strain improvement through adaptive evolution, environmentally friendly production strategies, and the utilization of proteases in the circular bio-economy particularly for waste valorization and by-product enhancement. It further discusses the interdisciplinary potential of bacterial proteases across multisector domains including environmental, agricultural, and industrial applications. These reviews summarize classification, enzyme production, optimization, catalytic mechanism, screening, applications, downstream processing and recent advance technologies, thereby highlighting their growing potential in sustainable industrial processing and future bio-catalytic innovations.