Preliminary Study on Keratinase Fermentation by Bacillus sp. MD24 under Solid State Fermentation

Abstract

Bacillus sp. MD24 has been reported to produce keratinase under submerged fermentation (SmF) using chicken feathers as sole carbon and nitrogen sources. However, the enzyme production was not preferable for industrial purpose due to relatively low enzyme yield. Solid state fermentation (SSF) was developed to improve keratinase productivity. Water content was varied to achieve optimum keratinase production. The effects of additional agricultural wastes to keratinase production were tested. The results showed that SSF improved keratinase production and optimum keratinase activity was achieved at the water content of 500%. Agricultural wastes (rice husk, sugar cane bagasse, and solid tofu-waste) significantly improved keratinase production. However, the production was delayed when rice straw and sugar cane bagasse were used. The highest activity at the fifth day was achieved when sugar cane bagasse was added to chicken feather medium.