Evaluation of different extraction methods on the polyphenols yield, flavonoids yield, and antioxidant activity of the pomelo flavedo extract from Da Xanh (Citrus maxima [burm] merr.) variety

Abstract

Pomelo peels have been well known as a valuable source of phenolic compounds mainly flavonoids. In this study, the influences of extraction conditions of three extraction methods on the polyphenols yield, flavonoids yield, and antioxidant activity of resulting pomelo flavedo extract (PFE) were evaluated. As a result, the suitable process parameters for the ultrasound assisted extraction were selected at an applied power of 120 W, the temperature of 60 ^oC for 20 min. Meanwhile, the microwave assisted extraction was operated at an applied power of 150 W for 25 min and the Soxhlet extraction was carried out up to 4 reflux cycles (35 min per cycle) at 80 ^oC. Among three methods, the microwave assisted extraction was considered as the most efficient method to obtain the high yield of polyphenols (80.56%) and flavonoids (86.58%). Naringin and hesperidin determined by high-performance liquid chromatography showed the value of 64.42 ± 2.90 mg/g DW and 0.97 ± 0.02 mg/g DW, respectively. The PFE extracted by the microwave assisted extraction could be a potent nutraceutical in further application on food or pharmaceutical industries.

Keywords:
pomelo flavedo extract; ultrasound assisted extraction; microwave assisted extraction; soxhlet extraction; antioxidant activity