Gas Chromatography-based Myrosinase Activity and QTL Mapping in Broccoli (Brassica oleracea L. var. Italica)

Vegetables in the Brassica genus have been shown to contain a number of compounds that exhibit pharmacological activity. This research elucidates genetic loci involved in the production of glucosinolate hydrolysis products, which are associated with anti-cancer bioactivity in broccoli (Brassica oleracea L. var. italica). The myrosinase (thioglucosidase EC 3.2.1.147) activities of 104 F_2:3 families from the mapping population BNC x VI158, grown in 2009 and 2010, were determined by the quantification of sinigrin (exogenous glucosinolate) hydrolysis products on a gas chromatography-flame ionization detector system. QTL analysis of the data was conducted in the software package MapQTL 5 (Van Ooijen, 2004) using a dense linkage map with 590 mapped SNP marker loci, covering an estimated 96% of the B. oleracea genome. This map was developed by Brown et al. (2014) using a 60K Illumina SNP array of Brassica napus, and is anchored to the genomic sequence of the rapid cycling Brassica oleracea T01000. The results of this study will provide useful information for the identification of genes involved in the chemopreventative activity of broccoli and support the breeding of Brassica cultivars that can serve as functional foods.