Novel liquid-liquid extraction and self-emulsion methods for simplified isolation of extra-virgin olive oil phenolics with emphasis on (-)-oleocanthal and its oral anti-breast cancer activity

Abstract

Epidemiological and clinical studies compellingly documented the ability of Mediterranean diet rich in extra-virgin olive oil (EVOO) to reduce breast and colon cancers incidence, cardiovascular diseases, and aging cognitive functions decline. (-)-Oleocanthal (OC) and other EVOO phenolics gain progressive research attention due to their documented biological effects against cancer, inflammations, and Alzheimer’s disease. There is no simple, reliable, and cost-effective isolation protocol for EVOO phenolics, which hinder their therapeutic applications. This study develops novel methods to isolate OC and other EVOO phenolics. This includes the use of ultra-freezing to eliminate most EVOO fats and the successful water capacity to efficiently extract OC and EVOO phenolics as self-emulsified nano-emulsion. Subsequent resin entrapment and size exclusion chromatography afforded individual EVOO phenolics in high purity. OC in vitro and in vivo oral anti-breast cancer (BC) activities validated its lead candidacy. Effective isolation of EVOO phenolics provided in this study will facilitate future preclinical and clinical investigations and stimulate the therapeutic development of these important bioactive natural products.