2018 ASHS Annual Conference

Redbud (Cercis spp.) is used globally as a spring flowering ornamental tree or shrub. Interest in colorants from plants to replace synthetic dyes used in foods has greatly increased in the last 10 years. Redbud flowers are of interest as a natural pigment source as they do not brown with senescence and all parts of the flower contain pigment. In this study, redbud flowers of 12 cultivars and lines, primarily from Cercis canadensis, were collected and anthocyanin pigments determined by high performance liquid chromatography and diode array detector. The anthocyanins cyanidin-3-glucoside, petunidin-3-glucoside, peonidin-3-glucoside, malvidin-3-glucoside, and 3,5- diglucosides of delphinidin, cyanidin, and petunidin were found in purple, rose, and red-purple redbud flowers. An acylated malvidin 3-glucoside was also present. Malvidin 3,5 diglucoside was the dominant pigment (60%) in the red-purple ‘Appalachian Red’ and ‘Crosswick’s Red’ while cyanidin 3-glucoside was dominant (60%) in flowers from the purple type cultivars such as ‘Oklahoma’, ‘Forest Pansy’ and ‘Traveller’. ‘Ruby Falls’ was intermediate (50%) in both cyanidin-3-glucoside and malvidin-3,5-diglucoside. Total amounts of anthocyanin were highest in ‘Oklahoma’, ‘Appalachian Red’, and ‘Ruby Falls’ and were 2-3 g cyanidin 3-glucoside or malvidin 3,5 diglucoside/kg dry weight. In comparison, blackberries contain 15-25 g cyanidin 3-glucoside/kg dry wt and ‘Concord’ grape juice contains about 5 g malvidin 3,5 diglucoside/kg dry weight.