Identification of Enzymes and Their Inhibition in Ash Gourd—An Approach to Extend Shelf Life

Abstract

Ash gourd (Benincasa hispida Cogn.) is a vegetable used in the Asian subcontinent, and believed to have medicinal value. Cut ash gourd pieces undergo severe decay within 3 days probably due to the enzymes xylanase, pectinase, amylase, and cellulase, which break the cell wall polysaccharides. Ash gourd pieces were screened for these enzymes. Though amylase and cellulase were absent, xylanase and pectinase were present. The enzymes were characterized for temperature and pH optimum, kinetic constants, and various inhibitors. The optimum temperature and pH for xylanase and pectinase were 50 and 60°C, and pH 5.0 and 4.0, respectively. One millimole of ethylenediaminetetraacetic acid (EDTA) with 10 mM NaCl mix completely inhibited xylanase and pectinase. Pretreatment using a combination of 1 mM EDTA and 10 mM CaCl2 is recommended as a first step in preservation of cut ash gourd.