Comparison of Glucoraphasatin and Glucoraphenin Content from Radish Plant during Vegetative and Reproductive Growth

Glucosinolates are secondary metabolites found abundant mainly in Brassicca vegetables and the importance of this compound has been sharply increasing due to being health benefits. The amounts of glucoraphasatin (GRH) and glucoraphenin (GRE) were compared from the commercial radish cultivars with seeds, young seedlings, mature plant, and flowers. All five genotypes showed much higher concentration of GRE in seeds compared to the other organs, approximately ranging 40 mM per gram dry mass. The concentration was sharply declined during germination and maintained basal level of concentration for the subsequent vegetative growth period. Contrary to this, the amounts of GRH, which is an immediate precursor of GRE, was steadily increased during early growth period up to 8 weeks old and remained a similar level. As growth of seedlings progressed, inner leaves contain much higher amounts of GRH than outer leaves. In root, little amount of GRE was found compared to the other tissues. However, GRH was abundant in roots and young root showed the highest. The results taken together, the reproductive organs tend to accumulate mainly GRE than GRH, however, the latter was found relatively high in roots and young leaves.