Effects of sodium nitroprusside on activity of acid and alkaline invertases and alkaline phosphatase in lemongrass (Cymbopogon flexuosus Steud) Wats

Abstract

We investigated effects of sodium nitroprusside (SNP) on sucrose metabolizing enzymes, acid, and alkaline invertase and alkaline phosphatase in lemongrass (Cymbopogon flexuosus Steud) Wats varieties i.e. Krishna, Cauveri, Nima and Cheerharit. Fifteen day old lemongrass tillers were treated with SNP (1 and 2 mM) under sunlight for four hours. Our results clearly indicated that SNP (2 mM) substantially decreased the amount of proteins in all varieties studied, with maximum values of 40% and 33% in Nima and Krishna, respectively. SNP (1 mM) significantly increased the amount of proteins 43% and 31% in Krishna and Cauveri, respectively. SNP (2 mM) rapidly and severely reduced the activity of acid and alkaline invertases in all varieties, except Krishna and Cauveri. However, the effect of SNP was more pronounced on acid invertase causing at 2 mM an inhibition of 37%, 35% and 28% in Cheerharit, Nima and Cauveri, respectively, whereas it showed relatively less inhibition in alkaline invertase activity 27%, 24% and 21%, respectively, in Nima, Krishna and Cheerharit. Alkaline phosphatase activity was only considerably decreased following SNP (2 mM) treatment in all lemongrass varieties studied with the exception of Nima, where a sharp decrease of 50% was observed. SNP (1 mM) also demonstrated similar effects on acid and alkaline invertases and alkaline phosphatase. These results clearly suggest that SNP affects acid and alkaline phosphatase activity and, therefore, has a role in sucrose metabolism in lemongrass. Alterations in alkaline phosphatase activity upon SNP treatment have several consequences. © D. Ganjewala et al.