Antibacterial activities of phytochemical constituents from the leaves of <i>Coula edulis</i> (Olacaceae) and <i>In silico</i> investigations of ursolic acid

From the leaves of <i>Coula edulis</i>, fourteen compounds were isolated and identified: D-mannitol (<b>1</b>), a mixture of β-sitosterol (<b>2</b>) and stigmasterol (<b>3</b>), α-amyrin (<b>4</b>), betulin (<b>5</b>), lupeol (<b>6</b>), lupenone (<b>7</b>), betulinic acid (<b>8</b>), taraxerol (<b>9</b>), 3β-(E)-coumaroyltaraxerol (<b>10</b>), 3β-(Z)-coumaroyltaraxerol (<b>11</b>), ursolic acid (<b>12</b>), stigmasterol 3-O-β-D-glucoside (<b>13</b>), and β-sitosterol 3-O-β-D-glucoside (<b>14</b>). These compounds were analysed through NMR spectroscopy (both 1D and 2D) and by comparing them to previously published data. Compounds <b>1</b>, <b>4</b>, <b>5</b>, and <b>7</b>-<b>9</b> have been identified from this species for the first time. Antibacterial activity was assessed, with compound <b>12</b> displaying the best efficacy against <i>Staphylococcus aureus</i> (MIC: 15.6 μg/mL). Molecular docking of compound <b>12</b> led to twenty lead compounds, among which <b>12 F</b> displayed the highest score (-10.1 kcal/mol). Most lead compounds showed better scores compared to Vancomycin (-8.8 kcal/mol). Biovia Discovery Studio analysis reveals lead compounds interacting with CASTp-predicted active pocket amino acids.