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Zeaxanthin dipalmitate (ZDP) is a major non-saponified carotenoid in fully ripe fruits of Lycium barbarum L. In the present study, response surface methodology was used to optimize the ultrasonic-assisted extraction (UAE) conditions of carotenoids from the fruits of L. barbarum, and the optimal extraction conditions were determined as follows: ultrasonic power of 360 W, ultrasonic time of 40 min and the ratio of extraction solvent to sample of 30 mL/g. An actual value of ZDP content of 5.40 mg/g and short extraction time indicated the efficiency of UAE. Furthermore, a promising high-speed counter-current chromatography (HSCCC) method was established for the purification of ZDP from the fruits of L. barbarum. With a developed two-phase solvent system composed of n-hexane/dichloromethane/acetonitrile (10/3/7, v/v/v), ZDP with a purity of higher than 95% was successfully isolated from the crude extract. This is the first report on the purification of ZDP by using HSCCC., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Fruits of Lycium barbarum L. have been used in Chinese traditional medicine for centuries. In the last decade, there has been much interest in the potential health benefits of many biologically constituents of these fruits. The high level of carotenoids offers protection against development of cardiovascular diseases, diabetes and related comorbidities. In the present work two different selections of Lycium barbarum L., cultivated in Italy and coming from three discrete harvest stages, were subjected to two different grinding procedure and to a simplified extraction method of carotenoid component. CIELAB colorimetric analysis of the freshly prepared purees and HPLC-DAD analysis of carotenoid extracts were performed and compared. Different harvesting dates and grinding procedures deeply influence the carotenoids content and statistical analysis showed high correlation between carotenoid content and colorimetric data. The final model provides a reliable tool to directly assess carotenoid content by performing cheap and routinely colorimetric analyses for food industry., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Due to the increasing popularity of goji berries, efforts are made to enlarge the offer of goji containing foods. In this study, rice flour based extrudates enriched with goji berries were investigated. The extrusion was performed using a twin screw extruder with constant feed moisture and screw speed. Raw mixtures as well as extruded products obtained were analysed in order to determine antioxidant activity and contents of rutin, zeaxanthin dipalmitate and 2-O-β-d-glucopyranosyl-l-ascorbic acid. The antioxidant activity of goji extrudates was boosted up to 20times compared to the extrudates without any addition. The process of extrusion increased the antioxidant activity despite of decrease in rutin content. Regardless of extrusion conditions rutin retention in the extrudates was not lower than 60% compared to the respective raw mixtures. In the case of zeaxanthin dipalmitate the retention level was around 40%. 2-O-β-d-glucopyranosyl-l-ascorbic acid was stable at the conditions applied., (Copyright © 2017 Elsevier Ltd. All rights reserved.)