Three new <i>α</i>-pyrone derivatives from the plant endophytic fungus <i>Penicillium ochrochloronthe</i> and their antibacterial, antifungal, and cytotoxic activities

Abstract

Three new 3,4,6-trisubstituted α-pyrone derivatives, namely 6-(2'<i>R</i>-hydroxy-3'<i>E</i>,5'<i>E</i>-diene-1'-heptyl)-4-hydroxy-3-methyl-2H-pyran-2-one (<b>1</b>), 6-(2'<i>S</i>-hydroxy-5'<i>E</i>-ene-1'-heptyl)-4-hydroxy-3-methyl-2H-pyran-2-one (<b>2</b>), and 6-(2'<i>S</i>-hydroxy-1'-heptyl)-4 -hydroxy-3-methyl-2H-pyran-2-one (<b>3</b>), together with one known compound trichodermic acid (<b>4</b>), were isolated from the solid-substrate fermentation culture of <i>Penicillium ochrochloronthe</i> associated the roots of <i>Taxus media</i>. Compounds <b>1-4</b> displayed the antimicrobial activity selectively against tested fungal and bacterial strains with minimum inhibitory concentration (MIC) values ranging from 12.5 to 100 μg/ml. Furthermore, we found that only compound <b>4</b> exhibited moderate cytotoxicity against five human cancer cells (A549, LN229, MGC, LOVO, and MDA231) with IC₅₀ values of 51.45, 23.43, 39.16, 46.97, and 42.85 μg/ml, respectively.