Ultrasound-assisted extraction (UAE) of bioactives from arecanut (Areca catechu L.) and optimization study using response surface methodology

The present study was undertaken on separation of polyphenols from the alkaloid, arecoline in arecanut (Areca catechu L.) by ultrasound assisted extraction (UAE) using 80% acetone at pH 4.0 as the extraction solvent. Response surface methodology using a central composite design (CCD) approach was used to investigate the influence of process variables such as sonication power, duty cycle and sonication time on total polyphenols, total tannins, arecoline content and antioxidant FRAP assay in the extracts so obtained. The maximum extraction of total polyphenols (362.59 mg GAE/g), total tannins (89.24 mg CE/g) and antioxidant activity by FRAP assay (1039.11 mM TEAC) with minimum arecoline (3.12 mg/g) was obtained using a sonication power of 30 W, a duty cycle of 50% and sonication time of 50 min. The RSM optimized extract was subsequently checked for antioxidant activity by hydroxyl scavenging (62%) and ABTS radical assay (511.06 mM TEAC).Industrial relevanceThis process aims at removal of cytotoxic molecule, arecoline, from arecanut. This will enable arecanut processing industry to produce phenolic extract which possess high antioxidant activity. Such extracts could be used as a source of polyphenolic nutraceuticals in food formulations. The strategy proposed in this work can become a boon to the farmers who are facing a ban on the cultivation of this cash crop. Further, it can direct the bioresource to be used for beneficial effects associated with polyphenols.

► Arecanut (Areca catechu L.) is a rich source of polyphenols but also contains toxic alkaloids, mainly arecoline.
► Separation of bioactive phenolics from toxic arecoline could propel the safe use of betel nut.
► Effect of UAE parameters such as sonication power, sonication time and duty cycle were evaluated.
► Ultrasonic extraction of arecanut gave a polyphenol rich extract with reduced content of arecoline.