The ripening stage of ginseng (Panax ginseng C.A. Meyer) berry influences its phytochemical compositions and their bioavailability

Ginseng root is the most popular medicinal herb in the world, whereas the berry has been considered a useless by-product. However, the presence of large amounts of bioactive compounds such as saponins and flavonoids in ginseng (Panax ginseng) berry suggests its potential as a functional resource for the food and medical industries. In this study, we evaluated the pharmaceutical value of ginseng berry by analyzing its antioxidant activity and anti-melanogenic effects and analyzed the variation in bioactivities of ginseng berry during the ripening process. As a result, the highest level of antioxidant and anti-melanogenic activities was observed in fully ripe berry extracts (Go-S3). Phytochemical screening showed that antioxidant and whitening activities mediated by polyphenolic compounds such as delphinidin-3-glucoside (1.1 ± 0.1 to 541.8 ± 5.4 μg/g of extract) and cyanidin-3-glucoside (0.5 ± 0.2 to 462.8 ± 11.7 μg/g of extract) increased during the ripening process. Furthermore, results obtained by quantitative real-time PCR, western blot, tyrosinase inhibition assay and molecular docking analysis suggested that Go-S3 probably inhibits tyrosinase activity by interacting with copper-coordinating histidines and second shell residues of tyrosinase, resulting in the reduction of melanin production in α-MSH-stimulated B16F10 cells. Taken together, these finding suggest the potential of ginseng berry as a resource for functional applications in the phytocosmetic industries and demonstrate that fruit ripening stages will be useful for further studies on ginseng berry for its applications in pharmaceutical industries.