Enzymatic analysis of recombinant CssANRa and CssANRb. (a) SDS-PAGE shows induction of recombinant pET31a+-CssANRa and T7 SUMO-CssANRb induced in E. coli, M: molecular weight markers, 1: protein profile prior to induction of pET31a+-CssANRa, 2: protein profile after induction of pET31a+-CssANRa for 3 h, 3: partially purification of supernatant of pET31a+-CssANRa, 4: prior to induction of T7 SUMO-CssANRb, 5: after induction of T7 SUMO-CssANRb for 3 h, 6: partially purification of supernatant T7 SUMO-CssANRb; (b–e) HPLC profiles show the formation of (−)-catechin [(−)-Ca] and (−)-epicatechin [(−)-EC] produced from incubations of cyanidin with recombinant CssANRa (b) and CssANRb (c) but not boiled CssANRa (d) and CssANRb (e); (f–i) HPLC profiles show the formation of (−)-gallocatechin [(−)-GC] (f) and (−)-epigallocatechin [(−)-EGC] produced from incubations of delphinidin with recombinant CssANRa (g) and CssANRb (h) but not boiled CssANRa (i) and CssANRb (j). (k), profiles of (−)-Ca, (−)-EC,(−)-GC, and (−)-EGC standards. (k–m), normal-phase chiral column based separation shows (−)-Ca and (+)-EC from CssANRa (k), (−)-Ca, (−)-EC, and (+)-EC from CssANRb (l) after incubation with cyanidin, and (−)-Ca and (−)-EC standards (m).