Análise fitoquímica dos extratos e frações obtidos de Himatanthus sucuuba

Abstract

The family Apocynaceae presents a wide variety of secondary metabolites with potential biological and pharmaceutical activities, which has attracted great interest in studies of their genres. The genus Himatanthus has thirteen species that are widely distributed in northern Brazil. The species of the Amazon region, Himatanthus sucuuba is a latex containing tree, whose trunk is erect and rough skin, popularly known as sucuba, sucuuba or janaguba. The latex, barks and leaves are used in folk medicine as antitumor, antifungal, anti-anemic, anthelmintic and for treatment of gastritis and arthritis. In the present study the roots of H. sucuuba were used to obtain hexane, dichloromethane and methanol extracts. From the hexane extract was isolated the mixture of lupeol cinnamates, α and β-amyrin. The dichloromethane extract was subjected to fractionation providing the iridoids plumericine, isoplumericine, plumieridine and the steroid sitosterol. From the methanol extract were isolated after successive fractionations, the iridoid plumieride and the terpenes lupeol acetate and the mixture of ursolic and oleanolic acids. The antioxidant activity was evaluated by sequestration capacity of the stable radical 2,2 - diphenyl-1-picrylhydrazyl (DPPH) using quercetin as standard. The methanol extract of the dried roots / the dichloromethane extract was better with antioxidant activity with the concentration of CS50 in 244.56 mg/mL. The toxicity test on Artemia salina hexane extract obtained from the fresh root, showed activity more pronounced at 111.06 mg/mL. Quantification of iridoids in different species of the genus Himatanthus proved the presence of plumieride as the major constituent in all analyzed species. The analysis of different samples analyzed by ultra efficient liquid chromatography coupled with mass spectrometry (UPLC-MS) led to the identification of iridoid 15-desmethylplumieride and plumieride, present only in the green fruits of the species H. sucuuba.