This study reports, for the first time, the presence of betalains in the apical leaves of Pereskia aculeata Mill., a species traditionally recognised for its nutritional, technological and medicinal value. While betalains production in P. aculeata callus cultures is documented, this research identified these compounds in apical leaves, optimised extraction conditions, evaluated colour stability at varying pH levels, and analysed the extract's antioxidant potential. Response surface methodology (RSM) using a Box-Behnken design was applied to optimise the extraction conditions. The optimal parameters were a mass/solvent ratio of 0.01 g/mL, extraction temperature of 45 °C, and extraction time of 3.42 min. The optimised extract exhibited antioxidant activity and marked colour variation under alkaline conditions. HPLC-DAD analysis showed co-elution with the betanin standard at 7.4 min, and UV-Vis spectra exhibited absorption maximum at 536 nm. These findings establish P. aculeata apical leaves as a novel and promising natural source of betalains.
Keywords: Betacyanins; Box–Behnken design; medicinal plant; ora-pro-nóbis.