Qualitative and quantitative evaluation of glucosinolates in cruciferous plants during their life cycles

Corresponding author: Hilmer Sørensen, Department of Natural Sciences, Biochemistry and Natural Product Chemistry, The Royal Veterinary and Agricultural University. Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark. Tel. +45 35282432; fax: +45 35282398; e-mail [email protected]; phone INTRODUCTION Glucosinolates are alkyl-N-hydroximine sulphate esters with a β-Dthioglucopyranoside group attached to the hydroximine carbon in Z-configuration relative to the sulphate group (Ettlinger and Kjær, 1968; Kjær, 1960; Sørensen, 1990). These compounds are allelochemicals biosynthetically derived from amino acids (Hill et al., 2003) and they occur in all plants of the Capparales order and in some other plants (Bjerg and Sørensen, 1987; Kjær, 1960; Rodman, 1978). Glucosinolates co-occur w i t h m y r o s i n a s e i s o e n z y m e s (Thioglucosidase; EC 3.2.1.147), which catalyze the hydrolysis of the β-Dthioglucopyranoside bond (Bellostas et al., 2003; Bjergegaard et al., 1994; Bjergegaard et al., 2003; Petersen et al., 2003). The released aglucones form a variety of biologically active products with structures defined by the type of glucosinolate and the reaction conditions (Bjergegaard et al., 1994; Buskov et al., 2000a; Buskov et al., 2000b; Buskov et al., 2000c; Palmieri et al., 1998). These breakdown products can be chemically very reactive, and they have for a long time been known for their biologically active characteristics, such as antinutritional (Bjerg et al., 1989; Hansen et al., 1997), anticarcinogenic (Bonnesen et al., 1999), fungicidal or bactericidal properties (Angus et al., 1994; Brown