ROLE OF ANTOXIDENTS IN THE PALATABILITY AND PRODUCTION POTENTIALS OF WATER YAM (DIASCOREA ALATA POIR CV KURUDU)

Vegetatively the head region of yam is the most productive part of the tuber. The present study evaluates some biochemical parameters responsible for the difference in the sensory properties and the high reproductive potentials of the head region of Dioscorea alata poir cv Kurudu. The experiment was performed using crude extracts of the yam tuber to measure activities of superoxide dismutase (SOD) and catalase, levels of lipid peroxidation and the concentrations of ascorbic acid in the three physiological regions. The highest level of lipid peroxidation was obtained in the middle region, while the tail had the lowest level. The activities of SOD were highest in the head followed by the middle and least in the tail. The activities of catalase are more or less the same in the head and middle regions, but very low in the tail region. The concentration of ascorbic acid is the same in the head and middle regions and low in the tail region. These observations indicate that increase in the activities of antioxidant enzymes and ascorbic acid levels with compromised levels of lipid peroxidation have crucial roles to play in the high sensory potentials of the head region of the yam tuber.