Box-Behnken design based multi-objective optimisation of sequential extraction of pectin and anthocyanins from mango peels

Abstract

Multi-objective sequential fractionation of mango (Mangifera indica L.) peels for pectin and anthocyanins in a biorefinery, was investigated with the aims of enhancing pectin purity, bioactivity and increasing recovered products. Anthocyanins were extracted from mango peels based on a Box-Behnken experimental design (ethanol concentration (50–80%), acetic acid concentration (0.1–2%), time (60–150 min) and temperature (25 °C)). The remaining residue was subsequently fractionated to recover pectin. The optimum anthocyanin conditions (67.45% ethanol, 0.24% acetic acid and 60 min) resulted in pectin with a 5.5% higher antioxidant activity, it was 23% richer in polygalacturonic acid (PGA) and had a yield of 31% w/w higher than conventionally extracted pectin. An anthocyanin extract with anthocyanin contents, polyphenol contents, and antioxidant activity of 22.33 mg/100 g, 132.62 mg/g, and 1.36 μg gallic acid equivalent, respectively, was obtained. Therefore, the sequential extraction of anthocyanins and pectin improves pectin functional properties and increases the mango peel value potential.