| ABSTRACT Ultraviolet B radiation has been described as a potential elicitor agent of the synthesis of secondary metabolites in plants. Thus, the present study aimed to investigate the production of betalains and total flavonoids, as well as the antioxidant activity, of Alternanthera sessilis, A. brasiliana, A. tenella and A. philoxeroides exposed to different periods of UV-B radiation (280-315 nm). Plants of these four species were exposed to UV-B radiation for 0, 2, 4, 6, and 8 hours, which amounts to 0, 10, 20, 30, and 40 J cm−2 of radiation, respectively. Significant increases in betacyanin and betaxanthin levels were observed in A. sessilis and A. brasiliana during the period of UV-B exposure, while no differences were observed for the others species.... |
