Extraction by maceration, ultrasound, and pressurized liquid methods for the recovery of anthocyanins present in the peel of guabiju (Myrcianthes pungens): Maximizing the extraction of anthocyanins from the peel of guabiju

Abstract

Guabiju (Myrcianthes pungens) is a fruit that stands out for its chemical composition, especially anthocyanins, which bring health benefits and can be used as natural dyes. However, there are no studies comparing different methods of extracting anthocyanins from guabiju peel. The objective of this work was to maximize the extraction of anthocyanins from guabiju peels by comparing the extraction methods of maceration, assisted by ultrasound, and pressurized liquid to characterize the obtained extracts. The extracts were characterized in terms of anthocyanin content, extract yield and productivity, soluble solids, color, acidity, total phenolic compounds, flavonoids, antioxidant activity, and the cost analysis involved in each methodology. The maximized conditions were absolute ethanol pH 1.0, fractional extraction (240 min) with solvent renewal in half the extraction time, 60 °C, 100 rpm of agitation in maceration, and 70 kHz by using ultrasound. The ultrasound assisted extraction method obtained the highest amount of anthocyanins (248.96 mg CE - cyanidin-3-glucoside equivalent/100 g) and an extract yield of 11.96%. For phenolic compounds and flavonoids (10,544.04 mg GAE - gallic acid equivalent/100 g and 1621.78 mg QE - quercetin equivalent/100 g), respectively, with good antioxidant capacity. Its properties and color allow for possible applications in different products. Ultrasound-assisted extraction showed a slightly lower cost of extraction than by maceration, while by PLE had a final cost approximately 2.4 times higher for 1 kg of anthocyanins.