Supercritical CO2 extraction of hemp seeds: A multivariate perspective on the influence of processing parameters on oil composition, antioxidant activity, and enzyme inhibition

Hemp seeds are valued for their unique nutritional and health benefits. This study examined the impact of supercritical (sc)CO₂ extraction conditions on hemp seed oil yield, composition, antioxidant activity, and enzyme inhibition using a multivariate approach. While pressure (300-500 bar) had minimal effects, temperature (40-60 °C) and ethanol addition (0.6-1.5 %) significantly influenced oil yield. The levels of fatty acids, tocopherols, carotenoids, chlorophylls, phenolics, and flavonoids varied independently of extraction pressure and temperature, but their extractability generally increased with ethanol concentration. The co-solvent addition also enhanced radical scavenging activity but diminished the metal-reducing and chelating properties. Hemp seed oils inhibited enzymes linked to chronic diseases like diabetes, skin disorders, and Alzheimer's. Multivariate analysis grouped samples by fatty acid profile, pigment content, and bioactivity. This work provides novel insights into how scCO₂ conditions affect the chemical and biological properties of hemp seed oils.