Chemical composition and anti- activities of essential oils from L. fresh and dry leaves and of its major constituent spathulenol.

Citrus canker, which is caused by , is a severe disease that affects citrus plants worldwide. This paper aimed to compare, for the first time, the chemical composition and anti- activities of essential oils from fresh and dry leaves (EO-FL and EO-DL, respectively). Anti- activity of spathulenol, the major constituent of oils, was also evaluated. Activities were screened by the broth microdilution method on 96-well culture plates. Three major constituents were identified in EO-FL and EO-DL by GC-MS and GC-FID: spathulenol, β-caryophyllene and caryophyllene oxide. EO-DL (MIC = 31.25 µg/mL), EO-FL (MIC = 62.5 µg/mL) and spathulenol (MIC = 100 µg/mL) were active against strains (resistant, tolerant and sensitive to copper). Even though results showed that potential of EO-FL, EO-DL and spathulenol against , further studies are needed to prove their applicability to the biocontrol of citrus canker.