Elite hairy roots of (L.) as a source of antioxidants and flavonoids.

An efficient protocol for hairy root induction in radish was established by optimizing several parameters that affect the efficiency of -mediated transformations. Explants wounded using sterile hypodermic needle, infected with suspension (0.6 OD) for 10 min and co-cultivated in 1/2 MS medium containing acetosyringone (100 µM) for 2 days displayed maximum percentage of hairy root induction using MTCC 2364 (77.6%) and MTCC 532 (67.6%). On further experiments with MTCC 2364 initiated hairy roots, maximum biomass accumulation (fresh weight = 9.50 g; dry weight = 1.48 g) was achieved in liquid 1/2 MS medium supplemented with 87.6 mM sucrose after 40 days of culture. Transgenic state of hairy roots of MTCC 2364 was confirmed by polymerase chain reaction using and -specific primers. The MTCC 2364-induced hairy roots produced higher amount of phenolic (33.0 mg g), flavonoid (48.0 mg g), and quercetin (114.8 mg g) content compared to auxin-induced roots of non-transformed radish. Furthermore, the results of ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl assay confirmed that the antioxidant activity of MTCC 2364 root extracts was improved when compared to auxin-induced roots of non-transformed radish. The present study offers a new insight in radish for production of phenolics and flavonoids (quercetin) using -mediated hairy root induction.