Glucosinolates within a collection of white head cabbages (Brassica oleracea var. capitata sub.var. alba) from Turkey

Glucosinolates of a population of white head cabbages collected from different geographical regions of Turkey were determined at two different plant developmental stages (early and late development). The glucosinolates detected were glucoiberin, glucoraphanin, sinigrin of aliphatics and glucobrassicin, neoglucobrassicin, 4-methoxyglucobrassicin and 4-hydroxyglucobrassicin of indoles. Variation were observed in terms of glucosinolate profile and levels. However, the most abundant glucosinolate observed was glucobrassicin synthesized at significantly high levels. While total aliphatic glucosinolate content of genotypes ranged from 0.33 - 5.63 kmolg super(-1) dw and 0.46 - 16.14 kmolg super(-1) dw at early and late developmental stages, respectively, in the first year, the levels ranged from 0.05 - 7.72 kmolg super(-1) dw and 0.12 - 14.60 kmolg super(-1) dw at early and late developmental stages, respectively, in the second experimental year. In general, aliphatic glucosinolate content of cabbages were low compared to indoles; glucobrassicin in particular. The presence of glucoiberin and glucoraphanin in almost all cabbage genotypes is promising. Potential individuals synthesizing aliphatic glucosinolates together with glucobrassicin at relatively higher levels were selected for future breeding purposes aimed to develop novel lines with improved health benefits. Results suggested that both aliphatic and indole glucosinolate levels were higher at later stages of development.