Flavonoid composition of red sorghum genotypes

The effect of genotype on flavonoid composition was investigated in 13 sorghum varieties using HPLC-DAD. Sorghums with red/purple secondary plant colour had the highest levels of 3-deoxyanthocyanins (32-680 mu g/g) with the black pericarp sorghums having the highest. Sorghums with red secondary plant colour had a high proportion of apigeninidin compounds (66-89%), which Suggested that secondary plant colour affects 3-deoxyanthocyanin composition. Red pericarp sorghums with tan secondary plant colour had the highest levels of flavones (60-386 mu g/g). Flavanones were also detected in all sorghums With a red pericarp (8-48 mu g/g) and secondary plant colour did not affect their levels (p > 0.05). The elevated 3-deoxyanthocyanin levels in the black sorghums were due to their pericarp colour. Black sorghum panicles that were exposed to sunlight during their development had three times more 3-deoxyanthocyanins (617 mu g/g) than those that were covered with a paper bag (212 mu g/g). This Study showed that flavonoid levels and composition were affected by sorghum genotype. This information will help sorghum breeders to produce sorghum genotypes with maximum levels of desired flavonoids. (C) 2009 Elsevier Ltd. All rights reserved.