Changes in Phytochemical Compositions and Biological Activities After Fermentation According to the Harvest Periods of Mountain-Cultivated Ginseng Sprouts

TL;DR

This study shows that fermenting mountain-cultivated ginseng sprouts boosts their health benefits more than when they are harvested at different times.

Contribution

The novel finding is that fermentation significantly enhances bioactive compounds in ginseng sprouts more than harvest timing.

Findings

Fermentation increased total phenolic and flavonoid content in ginseng sprouts.

Fermentation boosted levels of bioactive ginsenosides Rg3 and compound K.

Harvest timing had a limited effect compared to fermentation on phytochemical composition.

Abstract

This study investigated how harvest timing within the growing season and lactic acid bacterial fermentation influence the phytochemical composition and biological activities of mountain-cultivated ginseng sprouts (MCGS). Various nutritional and bioactive constituents were examined, and in vitro assays were conducted before and after lactic acid bacterial fermentation. Although all samples were derived from 5-year-old plants grown under the same cultivation conditions, differences in harvest timing within the same season may be associated with progressive environmental variation rather than plant age. Nevertheless, harvest timing exerted a relatively limited effect on overall metabolite variation, whereas fermentation significantly enhanced functional properties across all harvest stages. Fermentation increased total phenolic content (4.27 → 7.21 mg/g), total flavonoid content (0.47 → 1.38 mg/g), and Maillard reaction products (2.02 → 2.84 OD420nm), contributing to enhanced antioxidant capacity and increased inhibitory activities against pancreatic lipase and α-glucosidase. Notably, the levels of bioactive ginsenosides Rg3 and compound K increased markedly after fermentation (0.67 → 1.62 mg/g and 0.68 → 3.37 mg/g, respectively), despite a decrease in total ginsenoside content, indicating selective bioconversion during fermentation. Overall, these findings suggest that fermentation serves as the primary driver of functional enhancement in MCGS, while harvest timing within the growing season may play a secondary modulatory role.

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