The phytochemical investigation of Clusia lanceolata leaves yielded fourteen compounds including six flavones, vitexin, isovitexin, isovitexin-2"-O-α-L-rhamnopyranoside, vitexin-2"-O-α-L-rhamnopyranoside, orientin and isoorientin, two phaeophytins [132-hydroxy-(132-S-)-phaeophytin a and 132-hydroxy-(132-R)-phaeophytin a], two triterpenes, α- and β-amyrin, and four steroids, β-sitosterol, stigmasterol, sitosterone and stigmasterone. Their structures were assigned based on spectroscopic analysis, including two-dimensional NMR techniques and comparison with literature data. The antioxidant capacity in vivo of vitexin and mixing isovitexin-2"-O-α-L-rhamnopyranoside and vitexin-2"-O-α-L-rhamnopyranoside was evaluated using the yeast Saccharomyces cerevisiae as the biological system model and hydrogen peroxide as a stressor agent. The results showed that the tested flavonoids were able to protect the yeast cell against the oxidative damage caused by H2O2.

Essential oils of galled and non-galled leaves of Clusia lanceolataCambess., Clusiaceae, were obtained by hydrodistillation and analyzed by GC and GC/MS. The chemical composition of both oils was similar, with a predominance of sesquiterpene caryophyllenes. The extracts from the leaves were evaluated regarding total phenols, flavonoids and proanthocyanidins. Galled leaves showed higher levels of phenolics and proanthocyanidins, since the content of flavonoids was higher in non-galled leaves. The chromatographic profiles of extracts were obtained by using HPLC/DAD and LC-ESI-MS. Electrospray ionisation (ESI) in positive and negative ion mode was used to identify four flavones C-glycosides in both extracts. The study constitutes a first report on the chemical research of C. lanceolata.The extract from galled leaves had a higher antioxidant activity.