Chemical constituents from Bauhinia acuruana and their cytotoxicity

ABSTRACT Phytochemical investigation of Bauhinia acuruana Moric., Fabaceae, resulted in the isolation of sixteen constituents, including two new compounds 2'-hydroxy-2,3,5-trimethoxybibenzyl (1), (2R,3S)-2-(3,4'-dihydroxyphenyl)-5-methoxy-6-methylchroman-3,7-diol (2), together with fourteen known ones (3-16). The structures of the compounds were established by spectroscopic analysis including HR-ESI-MS, 1D and 2D NMR data, followed by comparison with previously reported data from the literature. Compounds 1, 2, 6, 7, 8 and 9 were evaluated for their cytotoxicity, which turned out to be marginal in a panel of six human cancer cell lines.

Use of GC/MS to identify chemical constituents and cytotoxic activity of the leaves of Phoradendron mucronatum and Phoradendron microphyllum (Viscaceae)

ABSTRACT Phoradendron mucronatum and P. microphyllum are plants that found in tropical and subtropical areas, used in traditional medicine and popularly known as mistle-thrush. The aim of this study was to identify the chemical constituents of different leaf extracts from P. mucronatum and P. microphyllum and assess cytotoxic activity against strains from a human tumour cells. Extracts obtained with hexane, dichloromethane, chloroform and ethyl acetate from the leaves were analysed by gas chromatography coupled with mass spectrometry (GC-MS) and the cytotoxicity was assessed by the MTT method (bromide (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)). The tested human tumour cells were NCI-H292 (human pulmonar mucoepidermoid carcinoma), MCF-7 (human breast adenocarcinoma) and HEp-2 (epidermoid carcinoma of the larynx). Analysis by GC/MS of the extracts from leaves of P. microphyllum and P. mucronatum detected 51 different compounds, such as alkaloids, diterpenes, triterpenes, sterols, alcohols, aldehydes, fatty acids and hydrocarbons. In the cytotoxic evaluation, hexane and ethyl acetate extracts from the leaves P. microphyllum inhibited cell growth of NCI-H292 strains (72.97%) and HEp-2 (87.53%), respectively. The extracts of P. mucronatum species showed an inhibitory effect towards NCI-H292 (83.19%/hexane), MCF-7 (88.69%/dichloromethane) and HEp-2 (93.40%/hexane). The extracts showed cytotoxic activity against the tested strains, especially the P. mucronatum, which presented the highest percentages of inhibition of cell growth.

Pharmacological screening and acute toxicity of bark roots of Guettarda platypoda

Due to its folk use, scientific reports and phytochemical screening, the purpose of this work was to study the phytochemical and the biological properties of the methanol extract and to evaluate the anti-inflammatory activity as well as determine the acute toxicity, antitumor and cytotoxic activity of the root barks of Guettarda platypoda DC., Rubiaceae. In this analysis the presence of flavonoids and therpenoids were identified. These data and the ones in the literature indicated it as a potential antioxidant and motivated the cytotoxic analysis related with three tumoral cell strains as well as to evaluate its antitumoral activity (sarcoma 180 and Ehrlich carcinoma) in female mice. Due to the presence of esteroids and the previous study of the ethanolic extract, its anti-inflammatory activity and toxicity were also evaluated. Absence or low toxicity in 2000 mg/kg doses was verified and the attention to their phytochemical and pharmacological properties is constantly increasing.

Chemical constituents of Lecythis pisonis and cytotoxic activity

The phytochemical investigation of the ethanol extract from leaves of Lecythis pisonis Cambess., Lecythidaceae, resulted in the isolation of seven triterpenes: α- and β-amyrin, uvaol and erythrodiol, ursolic and oleanolic acids and 3β-friedelinol, as well as a mixture of sitosterol and stigmasterol steroids and a diterpene (E)-phytol. The structures of these compounds were identified by¹H and 13C NMR spectral analysis and compared with literature data. The mixture of triterpenes ursolic and oleanolic acids isolated from the active ethereal fraction showed moderate cytotoxic activity. This paper describes for the first time the phytochemical and cytotoxic study of Lecythis pisonis' leaves.