Response surface methodology for aqueous two-phase system extraction: An unprecedented approach for the specific flavonoid-rich extraction of Houttuynia cordata Thunb. leaves towards acne treatment

双水相体系萃取的响应面法：一种前所未有的方法，用于鱼腥草叶中富含黄酮类化合物的特定提取，以治疗痤疮