COMPARATIVE STUDY OF ENZYME OXALATE OXIDASE IN PORTULACARIA AFRA (L.) JACQ. SUBJECTED TO ABIOTIC STRESSRuchira V. Javkar and Anil E. AvhadAbstract Several studies have reported the presence of higher levels of enzymes in plants subjected to drought and salinity stress compared to plants grown in control environmental conditions. The enzyme levels are often measured to understand the mechanisms that plants use to cope with these stressors and adapt to changing environmental conditions. Oxalate oxidase enzyme (OXO, EC 1.2.3.4.) is a glycoprotein that catalyses the oxidation of oxalate to carbon dioxide and hydrogen peroxide (Whittaker and Whittaker, 2002). Oxalate oxidase was purified to homogeneity from Portulacaria afra leaf samples subjected to abiotic stress by sequential ammonium sulphate precipitation and Sephadex C-50 gel filtration chromatography. The enzyme was purified with a recovery of 53.88% in Control while 76.53% in long-term drought and 78.66 % in long term salinity stress plants. The higher enzyme activity levels in stressed plants indicate that the plant is actively responding to the abiotic stress. Understanding the mechanisms that plants use to cope with stress can help in developing strategies to improve crop productivity under adverse environmental conditions. |