Anti-oxidative characterisation of NaN3-induced common bean mutants

The contents of total phenolics, total anthocyanins, total proanthocyanidins and antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl radicals scavenging activity, ferric reducing antioxidant power, lipid peroxidation inhibition ability and ABTS− radical-scavenging activity assays. These were compared in the seed coats of common bean (Phaseolus vulgaris L.) cultivar Hwachia and its eighteen NaN3-induced mutants. NaN3-induced mutants generally accumulated more total phenolics (19% more), total anthocyanins (65% more) and total proanthocyanidins (4% more) than Hwachia (containing 29.94 mg g−1 total phenolics, 0.31 mg g−1 total anthocyanins and 12.94 mg g−1 total proanthocyanidins, respectively). Anthocyanidins including delphinine, cyanidin and pelargonidin were detectable in seed coat, each with different levels depending on the tested accessions. Significant correlations (average of 0.847 across all comparisons, p < 0.01) were found between the tested antioxidant activities, total phenolics, total anthocyanins and total proanthocyanidins. Mutants SA-11-2, SA-13-2 and SA-34-2 that are enriched with antioxidants may be useful in food and other applications.