Composição química, compostos bioativos e atividade antioxidante de flores e raízes de Dahlia spp. em função das diferentes cores das flores

Abstract

The present study aimed to analyze the chemical composition and bioactive compounds of flowers and roots of dahlia from different varieties. Moisture content, crude protein, pH, total soluble solids, total titratable acidity, relationship between soluble solids and titratable acidity (ratio), minerals (P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn), anthocyanins, carotenoids, vitamin C, total phenolics, antioxidant activity by complex phosphomolybdenum reduction, DPPH inhibition percentage and protection of β-carotene percentage, as well as the activity of antioxidant enzymes such ascorbate peroxidase, superoxide dismutase and catalase, petals color, hydrogen peroxide contente and inulin content, were analyzed. Results were analyzed using Tukey’s test, revealing differences among some analyzed factors. The purple decorative flower exhibited the highest ratio value (39,04), whereas the highest ratio value for roots was observed in the red pompom (67,48). Pompom flowers showed superiority in antioxidant system performance, with the yellow having higher levels of carotenoids, phenolics, antioxidant activity (phosphomolybdenum and DPPH assays), and APX enzyme activity, and the red one having higher levels of anthocyanins, antioxidant activity (DPPH and β – carotene) and catalase activity, and along with the decorative red flower the highest levels of vitamin C. The red decorative flower also stood out for its minerals content, with a high content of Fe, mainly. Regarding roots, the red decorative plant showed higher levels for vitamin C and inulin, and together with the yellow decorative plant, for phenolics, with the yellow also stood out in terms of antioxidante capacity, indicating higher potential. Thus, the determination of plants with greater potential depends on the organ of interest, where for edible flowers production, the pompoms varieties and the red decorative excel, while for tuberous roots production, red and yellow decorative are superior.