Caracterisation des composes volatils et des polyphenols dans les feuilles et écorce des tiges de Croton sylvaticus Hochst (Euphorbiaceae) provenant de la République Démocratique du Congo

The aim of this study was to identify the volatile phytochemical compounds and to quantitatively determine the total polyphenol and flavonoid content in the leaves and stem barks of Croton sylvaticus Hochst collected in the Democratic Republic of Congo. Gas chromatography coupled with mass spectrometry (GC-MS) analysis of the extracts led to the identification of 35 volatile compounds in the leaves and 18 in the stem barks. The main compounds found in the leaves included limonene (11.93%), guaiadiene (8.37%), α-copaene (7.92%), valencene (7.57%), germacrene (6.42%), caryophyllene (6.06%), and humulene (3.03%), whereas the stem barks primarily contained α-pinene (9.05%), guaiadiene (4.17%), β-pinene (3.21%), and cyperene (3.06%). The identified compounds were mainly mono- and sesquiterpenes. The polyphenol and flavonoid contents were determined using the Folin-Ciocalteu and aluminum chloride methods, respectively. Dichloromethane, methanolic, and aqueous extracts showed average polyphenol contents of 57.98 ± 0.15 mg gallic acid equivalent per gram of dry matter and flavonoid contents of 32.7 ± 0.2 mg quercetin equivalent per gram. These results demonstrated the chemical potential of C. sylvaticus as a source of bioactive secondary metabolites.