Measurement of nicotinamide adenine dinucleotide & nicotinamide adenine dinucleotide phosphate in tomato leaves

Abstract

Nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) were assayed in extracts from 10 g samples of tomato leaf tissue by measuring the fluorescence of the extracts treated with methyl ethyl ketone before and after enzymatic reduction of the NAD and NADP. The method yields recoveries of 85-110% of NAD and NADP added to the leaf extracts and it is possible to measure concentrations of 1 x 10-7 M NAD or NADP. NAD and NADP were found to be present in the leaves in approximately equal concentrations of about 30 mu moles/g fresh weight. Tomato plants grown on either nitrate or ammonium N had similar concentrations of NAD and NADP in the leaves.