PT  - JOURNAL ARTICLE
AU  - V. Sciancalepore
AU  - V. Longone
AU  - F. S. Alviti
TI  - Partial Purification and Some Properties of Peroxidase from Malvasia Grapes
AID  - 10.5344/ajev.1985.36.2.105
DP  - 1985 Jan 01
TA  - American Journal of Enology and Viticulture
PG  - 105--110
VI  - 36
IP  - 2
4099  - http://www.ajevonline.org/content/36/2/105.short
4100  - http://www.ajevonline.org/content/36/2/105.full
SO  - Am J Enol Vitic.1985 Jan 01; 36
AB  - Peroxidase extracted from Malvasia grapes was purified 124-fold by ammonium sulfate fractionation followed by three successive column chromatographies on Bio-Gel P-100, DEAE-Sephadex A-50 and Phenyl-Sepharose CL-4B. Four anionic isoenzymes were detected by polyacrylamide disc gel electrophoresis. The molecular weight of the enzyme was estimated to be 40 000-41 000 by gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The pH and temperature optima of the purified enzyme were 5.5 and 40°C, respectively. At 65°C, it took two minutes to inactivate the peroxidase isoenzymes 50%, and at 85°C, these enzymes were almost completely inactivated after five minutes. Grape peroxidase showed a Km of 5.5 mM for guaiacol at optimum H2O2 concentration and a Km of 1.6 mM for H2O2 at optimum guaiacol concentration.