ABSTRACT The present study aimed to investigate the anti-inflammatory activity of ethanolic extract from Casearia sylvestris Sw., Salicaceae, leaves and to identify the compounds responsible for this activity. The ethanolic extract from C. sylvestris leaves was fractionated by solid phase extraction and the chemical composition of extract and fractions were assessed by chromatographic techniques. Casearin-like clerodane diterpenes were quantified in ethanolic extract (27.4%, w/w) and in fraction 2 of solid phase extraction (50.6%, w/w). Carrageenan-induced paw edema and carrageenan-induced pleurisy assays (rats) were used to evaluate anti-inflammatory activity of ethanolic extract, its fractions and clerodane diterpenes from C. sylvestris – caseargrewiin F and casearin B. The ethanolic extract was tested in the rat paw edema model and the doses tested (10 and 100 mg/kg) had no effect. In the pleurisy model, the extract doses of 300 and 500 mg/kg showed inhibitory effect. The fraction 2 of solid phase extraction (10 mg/kg), caseargrewiin F and casearin B (0.5 mg/kg) showed a significant reduction (p < 0.05) of the carrageenan-induced paw edema in rats compared to indomethacin. Gastric ulcers were not observed in animals treated with samples from C. sylvestris. In conclusion, the ethanolic extract from C. sylvestris, its enriched fraction of clerodane diterpenes, casearin B and caseargrewiin F exhibited anti-inflammatory activity on in vivo models in rats. Casearin-like clerodane diterpenes may be considered active chemical markers for C. sylvestris leaves. On the other hand, these diterpenes are promising compounds in the development of new drugs with anti-inflammatory action without gastric side effects.

Casearia sylvestris Swartz (Salicaceae) é uma planta utilizada na medicina tradicional, cujos extratos de folhas demonstraram importantes ações farmacológicas. A espécie apresenta variação morfológica, genética e química. Duas variedades são consideradas devido a diferenças morfológicas: C. sylvestris var.sylvestris e var. lingua. Há dificuldades na definição destas variedades. O objetivo deste trabalho é avaliar diferenças morfo-anatômicas e químicas entre as variedades de C. sylvestris que permitam sua diferenciação com aplicação farmacêutica ou botânica. Seções transversais e paradérmicas de folhas foram preparadas para análises morfo-anatômicas, histoquímicas e microscopia quantitativa (indices de estômatos e paliçada). Análises cromatográficas (CLAE-DAD e CCD) foram realizadas para obter o perfil de diterpenos clerodânicos. Os resultados das análises morfo-anatômicas demonstraram diferenças significativas entre as variedades somente em cortes paradérmicos: var.sylvestris - paredes celulares epidérmicas poligonais e hipoestomática, var. lingua - paredes celulares epidérmicas arredondadas e anfiestomática. Os índices de estômatos não revelaram diferenças; os valores dos índices de paliçada foram de 2,8 para var.lingua e 3,9 para var. sylvestris. As análises cromatográficas confirmaram resultados prévios, demonstrando predomínio de diterpenos na var.sylvestris. Este trabalho sugere que análises cromatográficas e morfo-anatômicas podem ser ferramentas aplicáveis na distinção das variedades da espécie.

Casearia sylvestris Swartz (Salicaceae) has been used in traditional medicine and its leaf extracts have been exhibited important pharmacological activities. The species presents morphological, chemical and genetic variation. Two varieties are considered due external morphological differences: C. sylvestris var. sylvestris and var. lingua. There are difficulties in definition of these varieties. The objective of this work is to evaluate chemical and morpho-anatomical differences between C. sylvestris varieties that can be applied in their distinction for pharmaceutical or botanical purposes. Transverse and paradermic sections of leaves were prepared for morpho-anatomical, histochemical and quantitative microscopy (stomatal and palisade index) analyses. Diterpene profiles of the specimens were obtained by HPLC-DAD and TLC. Morpho-anatomical analyses demonstrated significant differences between the varieties only in paradermic sections: var.sylvestris - polygonal epidermic cell walls and hypostomatic; var. lingua - rounded epidermic cell walls and amphistomatic. No differences were observed for stomatal index; palisade index was found 2.8 for var. lingua and 3.9 for var.sylvestris. Chromatographic analyses confirmed previous results demonstrating that diterpene profile in varieties differs, with predominance of these metabolites in var. sylvestris. In conclusion, this work indicates that chromatographic analysis besides morpho-anatomical analysis can be applied in distinction of C. sylvestris varieties.

Cytotoxic activity of eight plant extracts, native from the Mid-West of Brazil comprising Cerrado, Pantanal and semideciduous forest, was evaluated for MDA-MB-435, SF-295, and HCT-8 cancer cell strains. A single 100 µg.mL-1 dose of each extract was employed with 72 h of incubation for all tests. Doxorubicin (1 µg.mL-1) was used as the positive control and the MTT method was used to detect the activity. Cytotoxicity of distinct polarities was observed in thirty extracts (46%), from different parts of the following species: Tabebuia heptaphylla (Vell.) Toledo, Bignoniaceae, Tapirira guianensis Aubl., Anacardiaceae, Myracrodruon urundeuva Allemão, Anacardiaceae, Schinus terebinthifolius Raddi, Anacardiaceae, Gomphrena elegans Mart., Amaranthaceae, Attalea phalerata Mart. ex Spreng., Arecaceae, Eugenia uniflora L., Myrtaceae, and Annona dioica A. St.-Hil., Annonaceae. Extracts of at least two tested cell strains were considered to be highly active since their inhibition rate was over 75%.

Ethanolic extracts of the leaves of Casearia sylvestris yielded a novel clerodane diterpene, 15-hydroxy-3-cleroden-2-one, together with the known diterpenes (-)-hardwickiic acid, reported for the first time from this species, and casearins B and G, previously isolated from C. sylvestris. The structures of all four compounds were determined by spectrometric analysis. The new clerodane diterpene and (-)-hardwickiic acid contain structural features that are completely different from the highly oxygenated casearins and casearvestrins isolated from C. sylvestris.