Purification and Biochemical Characteristics of Pectinesterase from Malatya Apricot (Prunus armeniaca L.)

• Published in: Preparative biochemistry & biotechnology Vol. 38; no. 4; pp. 358 - 375
• Main Authors: Ozler, Aynur, Karakuş, Emine, Pekyardimci, Sule
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis Group 26.09.2008
• Subjects: Apricot; Carboxylic Ester Hydrolases - antagonists & inhibitors; Carboxylic Ester Hydrolases - isolation & purification; Carboxylic Ester Hydrolases - metabolism; Chromatography, Gel; Chromatography, Ion Exchange; Enzyme Inhibitors - pharmacology; Enzyme Stability; heat stability; Hydrogen-Ion Concentration; isolation; kinetic characterization; Kinetics; pectin; pectinesterase; Pectins - metabolism; Prunus; Prunus - enzymology; Prunus armeniaca; purification; Spectrophotometry, Ultraviolet; Substrate Specificity; Temperature
• ISSN: 1082-6068; 1532-2297
• DOI: 10.1080/10826060802325469

Pectinesterase (PE) in Malatya apricot pulp (Prunus armeniaca L.) was extracted and purified through (NH 4 ) 2 SO 4 precipitation, dialysis, and DEAE-Sephadex gel filtration chromatography. The samples obtained from the dialysis procedure, named partially purified enzyme, were used for characterization of the apricot pectinesterase. The effect of various factors such as pH, temperature, heat, and storage stability on the partially purified apricot PE enzyme was investigated. Optimum pH value was 9.0 for PE with 1% pectin in 0.1 N NaCl (w/v). The optimum temperature for apricot PE was found to be 60°C on standard analysis conditions. Heat inactivation studies showed a decrease in enzymatic activity at temperatures above 70°C. Km and V max values were 0.77 mM and 1.75 µmol min −1 mg −1 for apricot PE. Five inhibitors were tested in the study; the most effective inhibitor was found to be sodium carbonate (100% inhibition). The order of inhibitory effectiveness was: Na 2 CO 3 , iodine, lauril sulphate, AgNO 3 , EDTA. Thermal inactivation data indicated that apparent activation energy with pectin substrate was 2.96 kcal mol −1 for the enzyme. Ascorbic acid, CaCl 2 , and KCl showed activatory effect on the apricot PE enzyme.