Pilot Extraction and Component Analysis of Fat-Soluble Substances from Lycium barbarum L. and the Preparation of Major Carotenoids Monomer

In order to study the pilot production process for supercritical CO₂ extraction of fat-soluble substances from Lycium barbarum L., and for obtaining the preparation process of zeaxanthin dipalmitate monomer. The effect of pressure, temperature, time and co-solvent on the extraction yield of Lycium barbarum L. fat-soluble substances was studied, the orthogonal test was then used to optimize the extraction rate based on single factor experiment. The carotenoids and fatty acids in the fat-soluble substance of Lycium barbarum L. were analyzed by colorimetry, HPLC and GC-MS, and the zeaxanthin dipalmitate monomer was prepared by high performance preparative liquid chromatography. The results showed that the best pilot production process was that 15% ethanol was added, the extract temperature reached 50 ℃ and pressure reached 30 MPa, and extract for 1.5 h, when the yield and quality of fat-soluble substances were both considered. Under this process, the extraction rate of fat-soluble substances, unsaturated fatty acids and their proportion in total fatty acids, and the content of total carotenoids were relatively higher. While the extraction rate of fat-soluble substances was 8.55%, the content of unsaturated fatty acids was 80.958%, which accounts for 87.94% of the total fatty acid content, the content of total carotenoid and zeaxanthin dipalmitate was 37.64 mg·g⁻¹ and 29.54 mg·g⁻¹, respectively. The monomer of zeaxanthin dipalmitate with purity greater than 99% was prepared by pre-HPLC. In this study, the pilot-scale extraction process for supercritical CO₂ extract of fat-soluble substance and the preparation conditions of the zeaxanthin dipalmitate monomer from Lycium barbarum L. were obtained, which provided a basis for the research, development and utilization of the fat-soluble substances of Lycium barbarum L..