Multiple forms of glycosidases in an enzyme preparation from Aspergillus niger: Partial characterization of a β-apiosidase

Chromatofocusing on PBE 94 of a crude enzyme preparation from Aspergillus niger showed the presence of multiple forms of β-apiosidase, β-glucosidase, α-rhamnosidase, and α-arabinofuranosidase. A β-apiofuranosidase from the enzyme preparation was purified 27-fold by gel filtration and ion-exchange chromatography. The molecular mass of the enzyme and the K m value for p-nitrophenyl-β- d-apiofuranoside were 84,000 and 3.3 m m, respectively. The optimum pH and temperature for the enzyme activity were between pH 5.0–6.0 and 50–60°C, respectively. The enzyme was stable up to 50°C and between pH 4.0–7.0. Geranyl, linalyl apiosylglucosides, aroma precursors in grape, and a flavone apiosylglucoside were the substrates for the β-apiosidase.