The impact of medium composition and photosynthetically active radiation level on the initial in vitro growth and production of flavonoids of Vernonia condensata Baker

The use of techniques such as micropropagation can enable studying the chemical components of species with medicinal potential. However, the photosynthetically active radiation (PAR) supplied by the conventional illumination systems used for in vitro cultures is typically very low. The objective of this work was to evaluate the effect of variation of the sucrose content of the culture medium and the PAR level on the in vitro growth of Vernonia condensata, as well as to obtain the flavonoid profile of this species. Micropropagated shoots were inoculated in MS medium with half the normal saline concentration, supplemented with 15 g L−1 or 30 g L−1 of sucrose and 7 g L−1 of agar, and were maintained under three PAR levels: 40, 80 or 120 μmol m−2 s−1. Samples of the aerial part and root system of the plants subjected to the respective treatments were dried for quantitative analysis of the flavonoids by applying high-performance liquid chromatography (HPLC) to the hydromethanolic extract, with programming of the elution gradient. The HPLC method was validated according to the parameters specificity, linearity, precision, accuracy, limit of detection and limit of quantification. Rutin and quercetin 3-β-D-glucoside were the main flavonoids produced by this species when grown in vitro, with the aerial part producing more than the roots according to the quantification method used. The results demonstrate the influence of sucrose concentration and PAR intensity on the in vitro development and flavonoid profile of V. condensata.