The enhanced solubility and anti-lipase activity of citrus peel polymethoxyflavonoids extracts with liposomal encapsulation

Citrus peel polymethoxyflavonoids (PMFs), which exhibited a significant anti-lipase effect in functional foods, were widely used in diet therapy. However, its biological application was limited by the low content in citrus peel and poor solubility in water. To enhance the solubility and anti-lipase activity of citrus peel PMFs, the citrus peel PMFs extract was enriched by reflux extraction. Then, liposomes loaded with citrus peel PMFs extract (namely, PLS) were prepared by thin film hydration-high pressure homogenization method. Citrus peel PMFs extract, mainly including eight PMFs compounds such as nobiletin and tangeretin, were enriched from citrus peel with purity of 82.76%. The PLS prepared were spherical vesicles under transmission electron microscope (TEM), and they exhibited small particle size (70.94 ± 0.82 nm), high encapsulation efficiency (87.59 ± 2.55%), sustained release and good stability in characteristics. Furthermore, PLS showed significantly better solubility and stronger anti-lipase effect compared with free PMFs. Overall, PLS might be a potential anti-lipase inhibitor for obesity, which might allow the effective valorization of citrus peel and provide a potential value-added product used in dietary supplement.