Phytochemical analysis of Cedrelopsis grevei H. Baillon essential oil and evaluation of its antimicrobial and antifungal activity on plant pathogens

Cedrelopsis grevei H. Baillon is an aromatic and medicinal plant belonging to the Ptaeroxylaceae family from Madagascar. In this work, a detailed chemical characterization of the essential oil from the bark of C. grevei was performed, in combination with the evaluation of its antimicrobial activity. In particular, four samples of C. grevei essential oil were fully characterized by GC-MS and quantified by GC-FID. A total of 35 components were identified, according to their retention time data and mass spectra, representing 80% of the amount obtained by semi-quantification using relative response factors (RRFs) = 1. In the samples analyzed in this study, the major components were found to be ishwarane, β-elemene, α-copaene, calamenene, β-selinene, γ-muurolene, α-muurolene and β-pinene. Moreover, in addition to semi-quantification data, for the first time C. grevei essential oil quantification was performed by means of the experimental and predicted RRFs, using methyl octanoate as the internal standard. The biological activity of the essential oil was tested on plant pathogenic bacteria and fungi of interest in the ambit of biological agriculture and horticulture, including Agrobacterium tumefaciens, Agrobacterium vitis, Clavibacter michiganensis sub. michiganensis, Pseudomonas syringae pv syringae, Alternaria sp. and Fusarium oxysporum.