| Summary: | <i>Ginkgo biloba</i> L. stands as one of the oldest living tree species, exhibiting a diverse range of biological activities, including antioxidant, neuroprotective, anti-inflammatory, and cardiovascular activities. As part of our ongoing discovery of novel bioactive components from natural sources, we directed our focus toward the investigation of potential bioactive compounds from <i>G. biloba</i> fruit. The profiles of its chemical compounds were examined using a Global Natural Products Social (GNPS)-based molecular networking analysis. Guided by this, we successfully isolated and characterized 11 compounds from <i>G. biloba</i> fruit, including (<i>E</i>)-coniferin (<b>1</b>), syringin (<b>2</b>), 4-hydroxybenzoic acid 4-<i>O</i>-β-D-glucopyranoside (<b>3</b>), vanillic acid 4-<i>O</i>-β-D-glucopyranoside (<b>4</b>), syringic acid 4-<i>O</i>-β-D-glucopyranoside (<b>5</b>), (<i>E</i>)-ferulic acid 4-<i>O</i>-β-D-glucoside (<b>6</b>), (<i>E</i>)-sinapic acid 4-<i>O</i>-β-D-glucopyranoside (<b>7</b>), (1′<i>R</i>,2′<i>S</i>,5′<i>R</i>,8′<i>S</i>,2′<i>Z</i>,4′<i>E</i>)-dihydrophaseic acid 3′-<i>O</i>-β-D-glucopyranoside (<b>8</b>), eucomic acid (<b>9</b>), rutin (<b>10</b>), and laricitrin 3-rutinoside (<b>11</b>). The structural identification was validated through a comprehensive analysis involving nuclear magnetic resonance (NMR) spectroscopic data and LC/MS analyses. All isolated compounds were evaluated using an E-screen assay for their estrogen-like effects in MCF-7 cells. As a result, compounds <b>2</b>, <b>3</b>, <b>4</b>, <b>8</b>, and <b>9</b> promoted cell proliferation in MCF-7 cells, and these effects were mitigated by the ER antagonist, ICI 182,780. In particular, cell proliferation increased most significantly to 140.9 ± 6.5% after treatment with 100 µM of compound <b>2</b>. The mechanism underlying the estrogen-like effect of syringin (<b>2</b>) was evaluated using a Western blot analysis to determine the expression of estrogen receptor α (ERα). We found that syringin (<b>2</b>) induced an increase in the phosphorylation of ERα. Overall, these experimental results suggest that syringin (<b>2</b>) can potentially aid the control of estrogenic activity during menopause.
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