A comparative study of superoxide dismutase activity of different yam species

Abstract

The activity of superoxide dismutase (SOD) in three species of yam: Dioscorea cayenensis poir cv okpai, Dioscorea alata poir cv Chembeli and Dioscorea alata poir cv Kurudu was studied. The study demonstrated a significant variation of superoxide dismutase activity in the three varieties of Dioscorea species. The highest activity was found in Dioscorea cayenensis and the lowest one in Dioscorea alata poir cv Kurudu. The order of activity of the enzyme in the tuber was head > middle > tail physiological region. Inhibition studies with cyanide showed that the enzyme in the yam cell of all the varieties was inhibited by cyanide. These observations indicated that identical SODs are present in the cytosol and mitochondria of the yam cells of the different varieties studied.Thus different yam species vcxzhave different SOD activities that confer peculiar protective role against superoxide `' anion.

Keywords: Dioscorea alata, Dioscorea cayenensis, superoxide dismutase.


(Global Journal of Pure and Applied Sciences: 2002 9(1): 31-34)