Isolation of 4-Methylthio-3-butenyl Glucosinolate from Raphanus sativus Sprouts (Kaiware Daikon) and Its Redox Properties.
J Agric Food Chem. 2005 Dec 28;53(26):9890-9896.
Barillari J, Cervellati R, Paolini M, Tatibouet A, Rollin P, Iori R.
Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Istituto Sperimentale Colture Industriali, Bologna, Italy; Dipartimento di Chimica “G. Ciamician” and Dipartimento di Farmacologia, Alma-Mater Studiorum, Universita di Bologna, Bologna, Italy; and Institut de Chimie Organique et Analytique, Universite d’Orleans, Orleans, France.
The most promising among glucosinolates (GLs) are those bearing in their aglycon an extra sulfur function, such as glucoraphasatin (4-methylthio-3-butenyl GL; GRH) and glucoraphenin (4-methylsulfinyl-3-butenyl GL; GRE). The GRE/GRH redox couple is typically met among secondary metabolites of Raphanus sativus L. and, whereas GRE prevails in seeds, GRH is the major GL in full-grown roots. During the 10 days of sprouting of R. sativus seeds, the GRE and GRH contents were determined according to the Eurpean Union official method (ISO 9167-1). In comparison to the seeds, the GRE content in sprouts decreased from about 90 to about 12 mumol g(-)(1) of dry weight (dw), whereas a 25-fold increase-from about 3 to 76 mumol g(-)(1) of dw-of the GRH content was measured. An efficient pure GRH gram-scale production process from R. sativus (kaiware daikon) sprouts resulted in significant yield improvement of up to 2.2% (dw basis). The reaction of GRH with both H(2)O(2) and ABTS(*)(+) radical cation was investigated. Whereas H(2)O(2) oxidation of GRH readily resulted in complete transformation into GRE, ABTS(*)(+) caused complete decay of the GL. Even though not directly related to its radical scavenging activity, the assessed reducing capacity of GRH suggests that R. sativus sprouts might possess potential for health benefits.