The Extraction Technologies, Nutritional Compositions, and Health Benefits of Camellia oleifera Seed Oil̶A Review.

Camellia oleifera seed oil (COSO), a nutritionally rich oil from a key southern Chinese woody crop, has gained significance in food, cosmetic, and pharmaceutical fields. This review summarizes its high-value products, extraction technologies, chemical composition, and health benefits. High-value products include crude COSO and refined COSO, with by-products such as seed meal and shells that yield bioactive compounds for animal feed, fertilizers, and nutraceuticals. Extraction methods range from traditional mechanical pressing and solvent extraction to innovative approaches like supercritical CO2 extraction and enzyme/ultrasound/microwave-assisted techniques. Chemically, COSO features a balanced fatty acid profile dominated by oleic acid (52.13%-86.6%), along with abundant phytosterols, squalene, α-tocopherol, and phenolic compounds, which collectively enhance its oxidative stability and antioxidant activity. Health benefits include antioxidative and anti-inflammatory effects, cardiovascular protection, neuroprotection in Alzheimer's disease, anti-fatigue properties, antimicrobial activity, and osteoporosis prevention via mechanisms like NF-κB signaling modulation. In conclusion, COSO and its by-products offer nutritional, industrial, and therapeutic value, with innovative technologies promoting sustainability. Further research on large-scale optimization and by-product utilization is needed to fully exploit their potential in functional foods and healthcare.