The effect of nitric oxide, salicylic acid and hydrogen peroxide on the pigment content in excised cotyledons of red cabbage (Brassica oleraceae L.)

Abstract

The effects of nitric oxide (NO), salicylic acid (SA) and hydrogen peroxide (H2O2), known as messenger molecules, on the physiological processes were investigated in biotic and abiotic stress conditions in plants. The present study explored the effects of NO, SA and H2O2 on the content of photosynthetic pigments and anthocyanin, an antioxidant polyphenolic compound, in excised cotyledons of red cabbage Brassica oleraceae L. comparatively. As the experimental material, the cotyledons of 10-day-old etiolated B. oleraceae seedlings, excised from the petiole were incubated in 10 ml distilled water (control group) and in sodium nitroprusside (SNP), SA and H2O2 of various concentrations (0.1, 0.5 and 1 mu M) in the course of 4 hours light period. Following incubation, the pigments were spectrophotometrically measured from the extracts of the cotyledons, of which fresh weights were recorded. A comparative evaluation of the correlation between the applied messenger molecules and the measured values of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and anthocynanin was presented here. As a result, in case of total chlorophyll and carotenoid, inducing concentrations of SNP, SA and H2O2 were found to be 0.5 mu M, 1 mu M and 0.1 mu M, respectively. Of these messenger molecules, SNP was the most effective on anthocyanin at a concentration of 1 mu M.