Mamo G, Gessesse A
Department of Biology, Addis Ababa University, PO Box 1176, Addis Ababa, Ethiopia.
J Ind Microbiol Biotechnol. 1999 Jun;22(6):622-626. doi: 10.1038/sj.jim.2900676.
Aspergillus sp GP-21 produced a raw-starch digesting amyloglucosidase which showed optimum activity at 65 degrees C and pH 5.0-5.5. At 50 degrees C the enzyme converted about 40% of raw corn starch to glucose within 48 h. Enzyme production was studied in solid state fermentation using wheat bran. Productivity was affected by the level of moisture, incubation temperature and the presence or absence of supplements. Maximum enzyme production was observed at a moisture level of 75% and at 30 degrees C. Enzyme production was stimulated by supplementing wheat bran with 0.25% proteose peptone, 1% trace mineral solution, 0.01% CaCl2 and 0.01% MgSO4.
