Two C23-Steroids and a New Isocoumarin Metabolite from Mangrove Sediment-Derived Fungus Penicillium sp. SCSIO 41429

Two new C₂₃-steroids derivatives, cyclocitrinoic acid A (<b>1</b>) and cyclocitrinoic acid B (<b>2</b>), and a new isocoumarin metabolite, (3<i>R</i>,4<i>S</i>)-6,8-dihydroxy-3,4,5-trimethyl-7-carboxamidelisocoumarin (<b>10</b>), together with 12 known compounds (<b>3</b>-<b>9</b>, <b>11</b>-<b>15</b>) were isolated from the mangrove-sediment fungus <i>Penicillium</i> sp. SCSIO 41429. The structures of the new compounds were comprehensively characterized by 1D and 2D NMR, HRESIMS and ECD calculation. All isolates were evaluated for pancreatic lipase (PL) inhibitory and antioxidant activities. The biological evaluation results revealed that compounds <b>2</b>, <b>14</b> and <b>15</b> displayed weak or moderate inhibition against PL, with IC₅₀ values of 32.77, 5.15 and 2.42 µM, respectively. In addition, compounds <b>7</b>, <b>12</b> and <b>13</b> showed radical scavenging activities against DPPH, with IC₅₀ values of 64.70, 48.13, and 75.54 µM, respectively. In addition, molecular docking results indicated that these compounds had potential for PL inhibitory and antioxidant activities, which provided screening candidates for antioxidants and a reduction in obesity.