Enzymatic properties of a ferulic acid esterase from Aspergillus sojae

摘要

A major ferulic acid esterase (EC 3.1.1.73) was punned from a solid culture of Aspergillus sojae as an electropho-retically homogeneous protein. The molecular mass of the purified enzyme was estimated to be 30 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 29 kDa by gel filtration chromatography. The isoelectric point of the enzyme was 3.8. The purified enzyme had the highest activity toward partial hydrolyzate of starch free wheat bran with Driserase (HSFWB), and comparative but lower activities against methyl ferulate, methyl p-coumarate, methyl sinapinate and methyl 3，4-dimethoxy cinnamate. The findings therefore suggested that purified enzyme classified as type C or type D ferulic acid esterase.