An alkaline thermotolerant bacterial lipase of Bacillus coagulans MTCC-6375 was purified and immobilized on a methacrylic acid and dodecyl methacrylate (MAc-DMA) hydrogel. The lipase was optimally bound to the matrix after 20 min of incubation at 55 degrees C and pH 9 under shaking conditions. The matrix-bound lipase retained approximately 50% of its initial activity at 70-80 degrees C after 3 h of incubation. The immobilized lipase was highly active on medium chain length p-nitrophenyt acyl ester (C: 8, p-nitrophenyl caprylate) than other p-nitrophenyl acyl esters. The presence of Fe3+, NH4+, K+, and Zn2+ ions at 1 mM concentration in the reaction mixture resulted in a profound increase in the activity of immobilized lipase. Most of the detergents partially reduced the activity of the immobilized lipase. The immobilized lipase performed similar to 62% conversion in 12 h at temperature 55 degrees C.