Enhancement of food functionality of a local pungent radish “izumo orochi daikon” ‘susanoo’ by introduction of a colored root character

Abstract

Purple and red colored root characteristics were introduced to a local pungent radish “Izumo orochi daikon” ‘Susanoo’, and several characteristics including food functional components were evaluated. The root and leaf phenotype, the pigment composition, the isothiocyanate and soluble solids contents, and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in the root were investigated. These characteristics were compared between the mass selection breeding lines of purple, red roots and their parent cultivars. Although one-third of individuals in the M6 and M7 were non colored, the colored root characteristics was introduced into ‘Susanoo’. The main anthocyanins in the deep reddish purple colored purple root lines were acylated cyanidin 3-sophoroside-5-glucosides, and those in the vivid purplish red colored red root lines were acylated pelargonidin 3-sophoroside-5-glucosides, which corresponded to the main anthocyanins in their respective colored root parental cultivars. The isothiocyanate contents in the purple and red root lines were almost the same as that in ‘Susanoo’. The DPPH radical scavenging activity of the purple and red root lines was almost two times higher than that of ‘Susanoo’. These results showed that the food functionality was enhanced by introduction of a colored root characteristic in ‘Susanoo’.