Green Approaches to Carotenoid Extraction from Sea Buckthorn Fruit and Their Role in Ophthalmology

Hippophae rhamnoides L. is a valuable medicinal plant, distinguished by its rich content of bioactive compounds, mainly carotenoids and phenols. This study aimed to optimize the extraction of carotenoids from H. rhamnoides L. fruits using "green technologies" (ultrasonic bath and probe), as well as to evaluate the effect of various drying methods (atmospheric, vacuum, and freeze-drying) on carotenoid content and antioxidant activity. The research object was H. rhamnoides L. fruits, wild-growing in Western Georgia. Quantitative determination of carotenoids was carried out by the spectrophotometric method, and antioxidant activity was assessed by the DPPH radical scavenging method. The results of the study showed that ultrasonic probe extraction provides a high yield of carotenoids (1.564–3.363 mg/g dry weight), which significantly exceeds the values obtained by the classical method (1.111–2.944 mg/g). A correlation was established between carotenoid concentration and antioxidant activity. In particular, a high content of carotenoids (Akhaltsikhe, 3.363 mg/g) provides 50% inhibition of the DPPH radical with a relatively small amount of the sample (2.881 mg). Among the drying methods, freeze-drying (2.689 mg/g) and vacuum drying (2.481 mg/g) showed an advantage in preserving carotenoid content and antioxidant activity compared to atmospheric drying (1.778 mg/g). In conclusion, the use of "green technologies" is effective for obtaining bioactive compounds, which contribute to their use in ophthalmology, especially for the regeneration of eye surface damage. The data obtained forms the basis for further in vitro and in vivo studies.