Garcienone, a Novel Compound Involved in Allelopathic Activity of Garcinia Xanthochymus Hook

Abstract

Plants are sources of diversified allelopathic substances that can be investigated for use in eco-friendly and efficient herbicides. An aqueous methanol extract from the leaves of <i>Garcinia xanthochymus</i> exhibited strong inhibitory activity against barnyard grass (<i>Echinochloa crus-galli</i> (L.) P. Beauv.), foxtail fescue (<i>Vulpia myuros</i> (L.) C.C.), alfalfa (<i>Medicago sativa</i> L.), and cress (<i>Lepidium sativum</i> L.), and appears to be a promising source of allelopathic substances. Hence, bio-activity guided purification of the extract through a series of column chromatography steps yielded a novel compound assigned as garcienone ((<i>R, E</i>)-5-hydroxy-5-((6S, 9S)-6-methyl-9-(prop-13-en-10-yl) tetrahydrofuran-6-yl) pent-3-en-2-one). Garcienone significantly inhibited the growth of cress at a concentration of 10 μM. The concentrations resulting in 50% growth inhibition (<i>I</i>₅₀) of cress roots and shoots were 120.5 and 156.3 μM, respectively. This report is the first to isolate and identify garcienone and to determine its allelopathic potential.