Sequential high-pressure extraction of caffeine and bioactive compounds from caferana seeds (Bunchosia glandulifera)

Abstract Caferana (Bunchosia glandulifera) is a Brazilian plant that produces small red fruits with high nutritional value and possible anti-aging effects. This study aimed to evaluate the composition of caferana seed extracts obtained by sequential extractions with supercritical carbon dioxide in the first step, followed by pressurized liquid extractions using ethanol (second step) and water (third step) as solvents. Obtained extracts were characterized in terms of global yield, caffeine, tocols, fatty acids contents, and total phenolics, as well as their antioxidant activity, and results were thus compared with the conventional extraction method. Sequential extraction showed the best global yield (62.4 %). Supercritical carbon dioxide extract was more concentrated in caffeine (8.44 mg/g), and ethanolic one was more concentrated in total phenolic compounds with higher antioxidant activity capacity, whereas aqueous extract contained low levels of all monitored compounds. Overall, sequential extraction reveled increased selectivity and efficiency in obtaining extracts enriched with different compounds.