Recovery and determination of cholesterol-lowering compounds from Olea europaea seeds employing pressurized liquid extraction and gas chromatography-mass spectrometry

•Tyrosol, hydroxytyrosol, and β-sitosterol were extracted from olive seeds by PLE.•Hansen solubility parameters predicted greater extraction at high temperatures.•At 100 °C extracts showed the highest cholesterol lowering capacity.•Above 100 °C the degradation of these compounds or co-extractions can occur.•Tyrosol and hydroxytyrosol were the main contributors to hypocholesterolemic capacity. Our previous work demonstrated the presence of compounds with hypocholesterolemic capacity in olive seeds. These compounds were extracted using CO2-expanded ethyl acetate and identified as tyrosol, hydroxytyrosol, and β-sitosterol using GC–MS. This work describes the extraction of these compounds from different olive seeds using pressurized ethyl acetate. Their solubility in ethyl acetate at temperatures ranging from 40–200 °C was theoretically predicted by Hansen solubility parameters. The content of these compounds was estimated by GC–MS, as well as, the reduction of the micellar cholesterol solubility (RMCS) capacity of extracts enabling to establish the optimum extraction temperature at 100 °C. A GC–MS method was developed and validated in terms of its analytical characteristics for a sensitive determination and quantification of tyrosol, hydroxytyrosol, and β-sitosterol in different olive seeds. Within varieties, Manzanilla seeds presented the highest concentration of tyrosol, hydroxytyrosol, and the lowest concentration of β-sitosterol, as well as the highest RMCS capacity.