Two new polyketides from the mangrove endophytic fungus <i>Penicillium</i> sp. FDZ-018-102

Two new polyketides polyketiliums A and B (1 and 2), together with ten known polyketides (3–12) were isolated from the mangrove endophytic fungus Penicillium sp. FDZ-018-102. Their chemical structures were elucidated by spectroscopic methods. The absolute configurations of polyketilium B (2) was determined by electronic circular dichroism (ECD) calculations. All compounds were evaluated for their antifungal and antibacterial activities. The antifungal activity of compound 11 against Fusarium oxysporum f. sp. cubense was notable, with an EC50 value of 18.12 µg/mL, surpassing the efficacy of captan (EC50: 49.16 µg/mL) by more than twofold. Compound 11 showed equal MIC values of 32 μg/mL against both Staphylococcus epidermidis and Bacillus cereus, while compound 12 exhibited MIC values of 16 and 32 μg/mL, respectively.