Chemical constituents from Casearia spp. (Flacourtiaceae/Salicaceae sensu lato)

ABSTRACT Chemical investigation of the leaves of Casearia gossypiosperma Briq., Salicaceae, led to the isolation of two known flavonoids, (+)-taxifolin and quercetin, the leaves of Casearia decandra Jacq. have afforded hydroquinone, the leaves of Casearia rupestris Eichler and Casearia lasiophylla Eichler have afforded a diterpene, (E)-phytol, and the leaves of C. rupestris and Casearia obliqua Spreng. have afforded sitosterol. The twigs of Casearia lasiophylla Eichler led to the isolation of two compounds (+)-pinoresinol, and N-trans-feruloyltyramine, and the twigs of C. obliqua have afforded N-trans-feruloyltyramine, N-trans-cumaroyltyramine, and cinamic acid. This is the first report of the compounds (+)-taxifolin, quercetin, hydroquinone, (+)-pinoresinol and N-trans-cumaroyltyramine from the Casearia genus.

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.

The cytotoxic and antileishmanial activity of extracts and fractions of leaves and fruits of Azadirachta indica (A Juss.)

The leishmaniases are severe parasitic diseases that occur worldwide, caused by protozoa of the genus Leishmania. Studies with medicinal plants can lead to a range of possibilities for treating and improving the patients' quality of life. Research on Azadirachta indica fractions and extracts has shown that they have excellent anti-leishmanial activity based on bioactivity-guided fractionation of ethanolic extracts of leaves and seeds and in vitro activity against promastigotes. In this research the most efficient extracts and fractions were selected for tests on intracellular amastigotes of Leishmania amazonensis. The ethanolic extract of the leaves and dichloromethane and chloroform fractions had IC50 values of 38, 3.9 and 1.2 μg/mL for promastigotes and 9.8, 1.1 and 0.6 μg/mL for amastigotes, respectively, at 72 hours. For the ethanolic extract and dichloromethane fraction from nut tegument, the IC50 was 2.7 and 2.1 μg/mL for promastigotes and 0.4 and 0.6 μg/mL for amastigotes. The cytotoxicity of the fractions presented selectivity that was between 8 to 32 times more toxic to promastigotes and 15 to 72 times to amastigotes than to macrophages. The extracts and fractions from leaves and fruits were more effective against amastigotes, and the fractionation increased activity against both promastigotes and amastigotes, enabling us to obtain potentially active fractions with low toxicity.

Fenóis totais, atividade antioxidante e constituintes químicos de extratos de Anacardium occidentale L., Anacardiaceae / Total phenolics, antioxidant activity and chemical constituents from extracts of Anacardium occidentale L., Anacardiaceae

O presente artigo relata o isolamento e identificação do palmitato, oleato e linoleato de sitosterila, sitosterol, estigmasterol, 3-O-β-D-galactopiranosídeo do sitosterol, 3-O-β-Dgalactopiranosídeo do estigmasterol, 3-O-β-D-glicopiranosídeo do sitosterol e uma mistura de ácidos anacárdicos (monoeno e dieno) do extrato etanólico de cascas do caule de Anacardium occidentale L., Anacardiaceae, bem como do sitosterol, estigmasterol, lupeol, β-amirina, catequina e epicatequina do extrato etanólico do tegumento da castanha de caju in natura. Os extratos EtOH da casca e do tegumento foram avaliados quanto ao conteúdo de fenóis totais e atividade antioxidante. O extrato etanólico das cascas do caule apresentou maior conteúdo de compostos fenólicos e percentual de atividade antioxidante.

This paper describes the isolation and identification of a mixture of sitosteryl ester derivatives of fatty acids (palmitic, oleic and linoleic), sitosterol, stigmasterol, sitosterol-3-O-β-galactopyranoside, stigmasterol-3-O-β-galactopyranoside, sitosterol-3-O-β-glucopyranoside and a mixture of anacardic acids (monoene and diene) from stem bark of Anacardium occidentale L., Anacardiaceae, as well as sitosterol, stigmasterol, lupeol, β-amyrin, catechin and epicatechin from in natura cashew nut testa. Ethanol extracts from stem bark and testa were analyzed for antioxidant activity and total phenol content. The ethanol extract from stem bark exhibited the maximum of antioxidant activity and phenol content.

Gastroprotective effect of the ethanolic extract of Parkia platycephala Benth. leaves against acute gastric lesion models in rodents

Parkia platycephala Benth. (Leguminosae - Mimosoideae), popularly known as "visgueira", fava bean tree or "fava-de-bolota", is widely found in the Northern and Northeastern regions of Brazil. Its pods are used as cattle food supplement in the drought period. Compounds with a gastroprotective activity were obtained from the genus Parkia. Therefore, this study aimed at investigating the gastroprotective effect of the ethanolic extract of Parkia platycephala Benth. leaves (Pp-EtOH), as well as evaluating its possible mechanisms of action in experimental ulcer induction models. Lesions were induced by absolute ethanol, ethanol-HCl, ischemia-reperfusion and indomethacin in rodents. Pp-EtOH showed a protective effect in the lesion models (66, 48 and 52 percent, respectively), but it was not able to protect gastric mucosa against indomethacin-induced lesions. Results show a possible participation of the NO-synthase pathway in the gastroprotection and an antioxidant activity, by the increase of the catalase activity. The participation of prostaglandins and potassium channels sensitive to ATP in the gastroprotective effect of Pp-EtOH seems less likely to occur. More comprehensive studies, therefore, should be carried out to elucidate the antiulcerative effects of this promising natural product against this gastrointestinal disorder.

Atividade antibacteriana de plantas úteis e constituintes químicos da raiz de Copernicia prunifera / Antibacterial activity of useful plants and chemical constituents of the roots of Copernicia prunifera

Extratos etanólicos de Qualea grandiflora e Copernicia prunifera e extrato hexânico de Dipteryx lacunifera foram avaliados quanto a atividade antibacteriana, utilizando ensaios de difusão a partir de orifício e concentração inibitória mínima (CIM), frente a cepas Gram positivas e Gram-negativas, incluindo espécies multidroga resistentes. O extrato de Q. grandiflora apresentou atividade moderada para as cepas de Staphylococcus epidermidis (CIM = 500 µg/mL) e atividade fraca sobre as demais bactérias Gram-positivas testadas e inativo sobre bactérias Gram-negativas. Os resultados obtidos com S. epidermidis apesar de moderados são importantes, uma vez que este microorganismo é o principal causador de bacteremias e sepse associada com dispositivos médicos implantados. gama-Tocoferol e a mistura de sitosterol e estigmasterol foram isolados do extrato etanólico de raiz de C. prunifera e as estruturas destes compostos foram identificadas com base na análise dos dados espectrais de RMN e comparação com a literatura.

Ethanol extracts of Qualea grandiflora and Copernicia prunifera and hexane extract of Dipteryx lacunifera were evaluated by diffusion in agar and minimum inhibitory concentration (MIC) against Gram-positive and Gram-negative bacteria including multiresistant drug strains. The extract of Q. grandiflora presented moderate activity for Staphylococcus epidermidis (MIC = 500 µg/mL) and weak activity against other Gram-positive strains and inactive for Gram-negative species. The results obtained for S. epidermidis despite being moderate are important because this pathogen is often recovered from bacteremia and sepsis from infections of implanted devices. gamma-Tocopherol and the mixture of sitosterol and stigmasterol were isolated from the ethanol extract of the roots of C. prunifera. The structures of these compounds were identified by NMR spectroscopy and comparison with literature data.