Effect of selenium and sulfur fertilization on glucosinolate and isothiocyanates in Arabidopsis thaliana and rapid-cycling Brassica oleracea.

摘要

Evidence indicates that a diet high in Brassica vegetables reduces the risk of developing certain cancers and that dietary consumption has been highly associated with lower incidences of cancers such as colorectal, lung, and prostate. The chemopreventive properties of Brassica vegetables are often linked to glucosinolate (GS) degradation products. Isothiocyanates (ITCs) are extremely potent and have shown remarkable ability to act on the process of carcinogenesis by affecting all three phases: tumor initiation, promotion and progression phases, and also by suppressing the final steps of carcinogenesis. Selenium (Se) is an essential micronutrient in mammalian nutrition which exhibits antioxidant activity through inhibiting experimental carcinogenesis in animal models and reducing cancer incidence in human clinical trials. Plants of Arabidopsis thaliana and rapid-cycling Brassica oleracea were grown hydroponically in four blocks containing four replications of each treatment for both species. The treatments consisted of the control (half strength nutrient solution, containing no Se) and four Se treatments (0.4, 0.8, 1.6, and 3.2 mg Se L -1), one Se and elevated S combination treatment (0.8 mg Se L -1 and 37 mg SO 4 L -1 given in addition to the base 96 mg SO 4 L -1 in the nutrient solution), and one elevated S treatment (37 mg SO 4 L -1). Total GSs and ITCs decreased with increasing Se treatments in both A. thaliana and B. oleracea. Elevated sulfate treatment significantly increased GS and ITC concentrations in both A. thaliana and B. oleracea when compared to 1.6 and 3.2 mg Se L -1 treatments. Overall Se treatment affected GSs and ITCs in A. thaliana and B. oleracea. CT III International Symposium on Human Health Effects of Fruits and Vegetables - FAVHEALTH 2009, Avignon, France.