Kaffircorn malting and brewing studies XVII—Purification and properties of sorghum malt α‐amylase

Publisher Website
Google Scholar
Abstract
α‐amylase of sorghum malt has been purified by a combination of charcoal and heat treatment, DEAE‐cellulose and calcium phosphate chromatography, and gel filtration, yielding a product with a specific activity of 10,304 units per mg nitrogen. Both in the ultracentrifuge and on electrophoresis the purified α‐amylase revealed a single peak. Results are presented for the molecular weight, sedimentation, diffusion and amino‐acid composition of the purified enzyme. The influence of pH, temperature, and substrate concentration on the enzymic hydrolysis of gelatinised soluble starch has been studied. Examination of the purified α‐amylase on a calcium phosphate column showed that the enzyme is micro‐heterogeneous and it was separated into four sub‐fractions. The physical, chemical and kinetic properties of the sub‐fractions are almost identical.