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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..

Carotenoids from Lycium barbarum fruits have possessed pharmacological efficacy against eye diseases, cardiovascular disorders, cancer, and benign prostatic hyperplasia. However, the efficient extraction, rapid characterization and activities evaluation of Lycium carotenoids remains a challenge. To concentrate and characterize Lycium carotenoids, we have developed ultrasound-assisted extraction methods with different deep eutectic solvents (DESs) and analyzed carotenoids by ultra-performance convergence chromatography coupled with photo diode array detector and quadrupole time-of-flight mass spectrometry (UPC2-PDA-Q-TOF-MSE). DESs containing choline chloride and malonic acid presented better extraction efficiency and were more environmentally friendly than other extraction methods. Carotenoids were more quickly profiled (in 11 min) by UPC2 compared to by UPLC (in 35 min), with seventeen main peaks were characterized in the MS fragmentation patterns. The in vitro 5α-reductase inhibitory activity of DESs extracts, fractions and components were subsequently assessed, and the predominant component zeaxanthin dipalmitate (ZD) exhibited potent inhibitory activity. Our study provides a chemical and pharmacological basis for the further development of potential new drugs based on Lycium carotenoids.

In the present study, protein-polysaccharide Maillard conjugates were used as novel emulsifiers and bioactive carriers. Effects and potential mechanisms of zeaxanthin dipalmitate (ZD)-enriched emulsion stabilized with whey protein isolate (WPI)-gum Arabic (GA) conjugate (WPI-GA-ZD) and ZD-free emulsion (WPI-GA) on gut microbiota and inflammation were investigated using a model of dextran sulfate sodium (DSS)-induced colitis in mice. As a result, supplementation with WPI-GA and WPI-GA-ZD improved the serum physiological and biochemical indicators, decreased the expression of pro-inflammatory cytokines and related mRNA, as well as increased the tight junction proteins to a certain extent. 16S rDNA sequencing analyses showed that supplementation with WPI-GA and WPI-GA-ZD presented differential modulation of gut microbiota and played regulatory roles in different metabolic pathways to promote health. Compared with WPI-GA, the relative abundances of Akkermansia, Lactobacillus and Clostridium_IV genera were enriched by the intervention of WPI-GA-ZD. Overall, the designed carotenoid-enriched emulsion stabilized with protein-polysaccharide conjugates showed potential roles in promoting health.

Nowadays the xanthophylls lutein and zeaxanthin are used, in ophthalmic preparations for the prevention of age-related degeneration of the retina and cataracts. It is known that the carotenoids enter the body with plant foods or food additives derived from plant or microbial raw materials. They can be also obtained by means of chemical synthesis. Lutein is used in food industry as a colorant. Its source are the flowers of marigold ( ), which is are a common plant. Zeaxanthin is less available than lutein, so the search for new sources with a high content of xanthophyll is relevant. The plants, accumulating zeaxanthin and its esters are the fruits of Goji ( ), known in Chinese medicine as the Goji berry. In the berries zeaxanthin is present mostly in the esterified form, in the form of zeaxanthin dipalmitate. Water- and oil-soluble extracts of dried Goji berries (fruit of Wolfberry, ) have been obtained as a result of the experiment. The conditions of the chromatographic analysis were described with a thin layer chromatography (TLC) method and a high performance liquid chromatography (HPLC) method, and with the preparative separation of zeaxanthin with the method of column chromatography on aluminium oxide. Ultraviolet (UV) spectra of the samples obtained show that the absorption maximum of zeaxanthin standard and that of the sample obtained from the berries of Goji are the same. The optimum conditions to carry out saponification have been established. The content of xanthophyll in extracts is 13.5 mg/100 before saponification, 62 mg/100 g after saponification, 44 mg/100 g in purified ones. An aqueous extract of the berries can be used as a raw material for obtaining biologically active substances (BAS) or can be used as biologically active additives (BAA). It can be used to create a balanced xanthophyll drugs as well.