Abstract
Microbial enzymes improve feed digestibility but face challenges of high cost and low stability. In this study, we optimized the production of protease, lipase, cellulase, and amylase from Bacillus subtilis using response surface methodology. We purified the enzymes and encapsulated them in alginate beads to enhance performance. Encapsulation widened their active pH and temperature ranges. It also improved storage stability, with encapsulated enzymes retaining 60-74% activity after 30 days at 4 °C compared to 34-42% for free enzymes. These results show that alginate encapsulation increases enzyme robustness under variable conditions. The novelty of this work lies in the simultaneous optimization of four enzymes from one strain and their stabilization using a simple food-grade carrier. While the study demonstrates strong in vitro potential for poultry feed enrichment, in vivo trials are required to confirm practical application.