Bioactivity-Guided Isolation of Secondary Metabolites from Camellia fascicularis: Antioxidative Antibacterial Activities and Anti-Inflammatory Hypoglycemic Molecular Docking

<i>Camellia fascicularis</i> is a valuable ornamental, edible, and medicinal plant with promising prospects for bioactivity development. We screened the bioactivity of eight fractions (Fr. A-I) obtained from the ethyl acetate phase of <i>C. fascicularis</i> via silica gel column chromatography. The results indicated that the anti-inflammatory, antioxidative, and antimicrobial active components were mainly found in Fr. B*, E, A, and H; Fr. A-G; and Fr. D-I, respectively. Bioactivity-guided isolation identified 18 secondary metabolites. Compounds <b>1</b>, <b>3</b>-<b>5</b>, <b>7</b>, and <b>15</b>-<b>18</b> were isolated from the genus <i>Camellia</i> for the first time in this study, whereas the other compounds were also isolated from this plant for the first time. The structures of these compounds were elucidated through comprehensive spectroscopic techniques. Compounds <b>1</b>, <b>9</b>-<b>11</b>, <b>28</b>, <b>30</b>, and <b>31</b> demonstrated antioxidative activities comparable to those of ascorbic acid, whereas the remaining compounds exhibited diminished antioxidative activity. In terms of antimicrobial activity, compounds <b>7</b>, <b>18</b>, <b>22</b>, and <b>27</b> exerted inhibitory potency against <i>Pseudomonas aeruginosa</i>, similar to tetracycline (MIC: 125 µg/mL). Other compounds showed moderate to weak inhibitory effects against <i>Staphylococcus aureus</i> and <i>Escherichia coli</i> (MIC: 250-500 µg/mL). Molecular docking revealed that compounds <b>2</b>, <b>36</b>, <b>41</b>, and <b>65</b> showed strong binding affinity for <b>8ET0</b>, whereas compounds <b>2</b>, <b>36</b>, <b>38</b>, <b>40</b>, <b>63,</b> and <b>65</b> showed strong binding affinity for <b>3A4A</b>. This research further increased the diversity of the secondary metabolites of <i>C. fascicularis</i>, laying a foundation for the subsequent development and utilization of this species.