Ultrasonic-assisted aqueous two-phase extraction and purification of polyphenols from hawk tea (Litsea coreana var. lanuginose): Investigating its impact on starch digestion

Hawk tea, a conventional herbal beverage, is renowned for its beneficial properties in enhancing digestion and mitigating hyperglycemic tendencies. However, the extraction methodology for hawk tea polyphenols (HTP) has been understudied thus far, impeding its progress and broader application. To develop an efficient approach for HTP extraction, the present study introduced and optimized the application of ultrasonic-assisted aqueous two-phase extraction. Under optimal extraction conditions, the extraction yield of polyphenols from raw HTP was 7.86 %. During purification, LX-B14 was selected due to the highest adsorption and desorption abilities. Then in an in vitro simulated digestion system, HTP significantly reduced the expected glycemic index, raised the content of resistant starch, and decreased the activities of α-amylase and α-glucosidase, indicating its potential for alleviating starch digestion. Accordingly, the results provide an alternative approach for efficiently obtaining phenolic compounds from hawk tea, facilitating the advanced utilization of HTP within the food industry.