Nanoencapsulation of apigenin with whey protein isolate: Physicochemical properties, in vitro activity against colorectal cancer cells, and bioavailability

Abstract

Incorporating lipophilic phytochemicals with anti-cancer activities in functional beverages requires an appropriate nanoencapsulation technology. The present objective was to encapsulate apigenin with whey protein isolate (WPI) utilizing a pH-cycle method and subsequently characterize physicochemical properties, the <i>in vitro</i> anticancer activities against human colorectal HCT-116 and HT-29 cancer cells, and the <i>in vivo</i> bioavailability. Up to 2.0 mg/mL of apigenin was nanoencapsulated with 1.0 mg/mL WPI, with an encapsulation efficiency of up to 98.15% and loading capacity of up to 196.21 mg/g-WPI. Nanodispersions were stable during storage, and apigenin became amorphous after encapsulation. Nanoencapsulation and <i>in vitro</i> digestion did not reduce the anti-proliferative activity of apigenin. Nanoencapsulation of apigenin enhanced the cellular uptake, the pro-apoptotic effects, and the bioavailability in the mice's blood and colon mucosa when comparing to the unencapsulated apigenin. Therefore, the present work may be significant to incorporate lipophilic phytochemicals in functional beverages for disease prevention.