Chemical composition of the volatile oil of <i>Croton glandulosus</i> Linnaeus and its allelopathic activity

Abstract

Several essential oils have allelochemicals with phytotoxic effects. <i>Croton</i> species are producers of secondary metabolites with biological potential. In the present study, chemical composition of the essential oil extracted from aerial parts of <i>Croton glandulosus</i> Linnaeus was evaluated by gas chromatography and the phytotoxicity of the oil on <i>Lactuca sativa</i> seeds was evaluated for the first time. The yield of the essential oil was 0.12% (v/w). Chromatographic analysis allowed the identification of 97.49% of the total compounds present in the oil. Sesquiterpenes were found to be the predominant constituents of the volatile oil, with <i>β</i>-caryophyllene (53.24%) being the major compound. Treatment with 0.1%-1% (v/v) of the essential oil inhibited the development of the hypocotyl and radicle of <i>L. sativa</i> to a greater extent compared to the inhibition of seed germination, demonstrating the phytotoxic effect of the oil.