Glucosinolate contents and patterns in different organs of Chinese cabbages, Chinese kale (Brassica alboglabra bailey) and choy sum (Brassica campestris L. ssp chinensis var. utilis Tsen et Lee)

The composition and distribution of glucosinolates were studied in different plant organs (inflorescences, stems, leaves) of the two Chinese Brassica vegetables Chinese kale (Brassica alboglabra Bailey) and Choy sum (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee). The total amounts of glucosinolates varied significantly between and within the two species. It was highest in inflorescences, followed by stems and leaves. In Chinese kale values of 1255.64, 335.71, and 168.43 mu mol 100 g(-1) FW and in Choy sum 569.32, 153.13, and 45.38 mu mol 100 g(-1) FW were round, respectively. The predominant glucosinolates in Chinese kale were 3-butenyl (gluconapin) and 4-methylsulfinylbutyl glucosinolate (glucoraphanin), and in Choy sum gluconapin and 2-hydroxy-3-butenyl glucosinolate (progoitrin). In both species, four indolyl glucosinolates were identified in each organ.