Atividade antimicrobiana dos extratos metanólicos da raiz, caule e folhas de Croton pulegioides Baill. (Zabelê) / Antimicrobial activity of methanol extracts of root, stem and leaves of Croton pulegioides Baill

O uso popular de plantas medicinais continua sendo de grande interesse para a população, principalmente em países em desenvolvimento, nos quais o acesso à medicina alopática ainda é muito restrito. Assim, além de sua importância na medicina tradicional, o conhecimento das plantas pode fornecer para a indústria farmacêutica, direta ou indiretamente, princípios ativos de interesse terapêutico. No presente trabalho foi avaliada a atividade antimicrobiana dos extratos metanólicos secos de Croton pulegioides Baill. obtidos a partir da raiz, do caule e das folhas nas concentrações de 25, 50 e 100mg/mL utilizando o método de difusão em Agar (técnica de poços) frente a cinco cepas Gram-positivas, três cepas de fungos e três cepas de bactérias Gram-negativas. Na execução do estudo foi utilizado o antibiótico Gentamicina (100µg/mL) no teste com bactérias, e Cetoconazol (300µg/mL) para as Candidas verificando-se, ao mesmo tempo, a ausência de atividade para o diluente DMSO 20% em água. Na observação dos resultados evidenciaram-se halos de inibição indicando atividade dos extratos metanólicos da raiz, caule e folhas, nas concentrações de 50 e 100mg/ml, frente Bacillus subtilis AM 04; dos extratos metanólicos da raiz e do caule, nas concentrações de 50 e 100mg/ml, frente Staphylococcus aureus AM 103 (ATCC 6538); e do extrato metanólico do caule, nas concentrações de 50 e 100mg/ml, frente S. epidermidis AM 235. Por outro lado, todos os extratos foram inativos nas concentrações avaliadas frente às bactérias Gram-negativas utilizadas no estudo (Pseudomonas aeruginosa AM 206, Escherichia coli AM 1050 e Klebsiella pneumoniae AM 410). Referente à atividade sobre fungos, os extratos metanólicos da raiz e do caule inibiram, nas três concentrações avaliadas, o crescimento de Candida tropicalis AM 1181 e C. albicans AM 1140, enquanto o extrato das folhas, inibiu o crescimento de C. tropicalis AM 1181 nas concentrações de 50 e 100mg/ml e de C. albicans AM 1140 apenas na concentração de 100mg/mL. Finalmente o extrato metanólico das folhas, na concentração de 100mg/mL, foi o único a inibir o crescimento de Candida krusei. Os resultados preliminares apresentados pelo presente trabalho sugeriram que a espécie Croton pulegioides Baill. apresentou resultados promissores quanto ao potencial antimicrobiano.

The employment of medicinal plants as a folk custom remains important to the present time, mainly in developing countries, where access to allopathic medicine is restricted. Besides their importance in traditional medicine, the knowledge on these plants can, directly or indirectly, provide information about the active ingredients involved, which may be of interest to the pharmaceutical industry. The present study evaluated the antimicrobial activity of dried methanolic extracts of Croton pulegioides Baill, extracted from its roots, stalk, and leaves, at the concentrations of 25, 50 and 100mg/ml. These were diffused in wells with an Agar medium, to which five strains of Gram-positive, three strains of fungi and three strains of Gram-negative bacteria had been added. For this study, the antibiotic Gentamicin (10µg/100µL) was used in tests with bacteria, and Ketoconazole (30µg/100µL), with Candidas. When DMSO diluted in 20% water was used, no activity was observed. The results produced evidence of inhibition halos, which indicates the activity of the methanolic extracts from the roots, stalk and leaves at the concentrations of 50 and 100 mg/ml for Bacillus subtilis AM 04; activity of the methanolic extracts from the roots and stalk at the concentrations of 50 and 100mg/ml for Staphylococcus aureus AM 103 (ATCC 6538); and activity of the methanolic extract from the stalk at the concentrations of 50 and 100mg/ml for Staphylococcus epidermidis AM 235. There was no activity in the concentrations studied for the Gram-negative bacteria (Pseudomonas aeruginosa AM 206, Escherichia coli AM 1050 and Klebsiella pneumoniae AM 410). With respect to fungal activity, the methanolic extracts from the roots and stalk inhibited Candida tropicalis AM 1181 and C. albicans AM 1140 at the three concentrations studied. The extract from the leaves inhibited the growth of C. tropicalis AM 1181 at the concentrations of 50 e 100mg/ml and C. albicans AM 1140 only at the concentration of 100mg/ml. Finally, the methanolic extract from the leaves, at the concentration of 100mg/ml, was the only one to inhibit the growth of Candida krusei. Preliminary results from this study suggest that the Croton pulegioides Baill showed promising results as a potential antimicrobial agent.

Atividade antimicrobiana e sinérgica das frações das folhas de Schinopsis brasiliensis Engl. frente a clones multirresistentes de Staphylococcus aureus / Antimicrobial and synergic activity of fractions from the leaves of Schinopsis brasiliensis Engl. against Staphylococcus aureus multiresistant clones

No presente estudo objetivou-se avaliar a atividade antimicrobiana e sinérgica de 4 frações das folhas de Schinopsis brasiliensis Engl (F1', F2', F1" e F2") frente às cepas Staphylococcus aureus MRSA multirresistentes. Os métodos utilizados foram poços de difusão em ágar, concentração mínima inibitória (CMI) - diluição em ágar, e bioautografia. Nos resultados bioautográficos observou-se três halos de inibição relacionados, no mínimo, à quatro constituintes ativos; sendo dois deles isolados das folhas (galato de metila e ácido gálico). A F2" (200∝g/mL) apresentou halos de inibição de 16 e 19mm frente as cepas de S. aureus multirresistente e Klebsiella pneumoniae, e CMI 100∝g/mL, respectivamente. Quanto as análises das associações das frações F1" ou F2" (25 e 50∝g/mL) com a tetraciclina e oxacilina, mostraram ações aditiva e sinérgica para a F2" (50∝g/mL), embora não suficiente para que a CMI atingisse valores inferiores a 2 e 4∝g/mL, necessário para serem classificadas como cepas sensíveis a oxacilina e tetraciclina, respectivamente. "Assim, conclui-se que a F2" das folhas de S. brasiliensis apresentou potencial antimicrobiano frente às cepas de S. aureus MRSA multirresistentes e que as associações das frações com os antibióticos testados não apresentaram benefícios não justificando o uso concomitante.

The aim of this study was to evaluate the antimicrobial and synergic activity of 4 leaf fractions of Schinopsis brasiliensis Engl (F1', F2', F1" and F2") against multidrug-resistant Staphylococcus aureus strains. The used methods were agar well diffusion, minimum inhibitory concentration (MIC) - agar dilution, and bioautography. The bioautographic results showed three inhibition zones that corresponded to at least four active compounds, two of which (methyl gallate and gallic acid) have already been isolated from leaves. The F2" (200∝g/mL) fraction showed inhibition zones of 16 mm and 19 mm against S. aureus multidrug-resistant and Klebsiella pneumoniae strains and a MIC value of 100∝g/mL, respectively. The analyses of associations of fraction F1" or F2" (25 and 50∝g/mL) with tetracycline and oxacillin showed additive and synergistic action for F2" (50∝g/mL), although it was not enough to decrease the MIC values to less than 2 and 4∝g/mL, necessary to classify the strains as susceptible to oxacillin and tetracycline, respectively. Thus, it was concluded that F2" from the leaves of S. brasiliensis showed antimicrobial potential against multidrug-resistant MRSA strains, and the associations of the fractions with the tested antibiotics showed no benefits, not justifying their concomitant use.

Acute and subacute toxicity of Schinus terebinthifolius bark extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Schinus terebinthifolius Raddi (Anacardiaceae) has long been used in traditional Brazilian medicine, especially to treat inflammatory and haemostatic diseases. AIM OF THE STUDY: The objective of this study was to evaluate the acute and subacute toxicity (45 days) of Schinus terebinthifolius via the oral route in Wistar rats of both sexes. MATERIALS AND METHODS: For the acute toxicity test, the dried extract of Schinus terebinthifolius bark was administered in doses from 0.625 to 5.0 g/kg (n=5/group/sex) and in the subacute toxicity test the following doses were used: 0.25, 0.625 and 1.5625 g/kg/day (n=13/group/sex), for 45 consecutive days. RESULTS: In the acute toxicity test, Schinus terebinthifolius did not produce any toxic signs or deaths. The subacute treatment with Schinus terebinthifolius did not alter either the body weight gain or the food and water consumption. The hematological and biochemical analysis did not show significant differences in any of the parameters examined in female or male groups, except in two male groups, in which the treatment with Schinus terebinthifolius (0.25 and 0.625 g/kg) induced an increase of mean corpuscular volume values (2.9 and 2.6%, respectively). These variations are within the physiological limits described for the specie and does not have clinical relevance. CONCLUSION: The acute and subacute administration of the dried extract of Schinus terebinthifolius bark did not produced toxic effects in Wistar rats.

Zea mays L. extracts modify glomerular function and potassium urinary excretion in conscious rats.

Diuretic and uricosuric properties have traditionally been attributed to corn silk, stigma/style of Zea mays L. Although the diuretic effect was confirmed, studies of the plant's effects on renal function or solute excretion were lacking. Thus, we studied the effects of corn silk aqueous extract on the urinary excretion of water, Na+, K+, and uric acid. Glomerular and proximal tubular function and Na+ tubular handling were also studied. Conscious, unrestrained adult male rats were housed in individual metabolic cages (IMC) with continuous urine collection for 5 and 3 h, following two protocols. The effects of 25, 50, 200, 350, and 500 mg/kg body wt. corn silk extract on urine volume plus Na+ and K+ excretions were studied in water-loaded conscious rats (2.5 ml/100 g body wt.) in the IMC for 5 h (Protocol 1). Kaliuresis was observed with doses of 350 (100.42 +/- 22.32-120.28 +/- 19.70 microEq/5 h/100 g body wt.; n = 13) and 500 mg/kg body wt. (94.97+/- 29.30-134.32 +/- 39.98 microEq/5h/100 g body wt.; n = 12; p<0.01), and the latter dose resulted in diuresis as well (1.98 +/- 0.44-2.41 +/- 0.41 ml/5 h/100 g body wt.; n = 12; p<0.05). The effects of a 500 mg/kg body wt. dose of corn silk extract on urine volume, Na+, K+ and uric acid excretions, and glomerular and proximal tubular function, were measured respectively by creatinine (Cler) and Li+ (ClLi) clearances and Na+ tubular handling, in water-loaded rats (5 ml/100 g body wt.) in the IMC for 3 h (Protocol 2). Clcr (294.6 +/- 73.2, n = 12, to 241.7 +/- 48.0 microl/ min/100 g body wt.; n = 13; p<0.05) and the Na+ filtered load (41.9 +/- 10.3, n = 12, to 34.3 +/- .8, n = 13, p<0.05) decreased and ClLi and Na+ excretion were unchanged, while K+ excretion (0.1044 +/- 0.0458, n=12, to 0.2289 +/- 0.0583 microEq/min/100 body wt.; n = 13; p<0.001) increased. For Na+ tubular handling, the fractional proximal tubular reabsorption (91.5 +/- 3.5, n = 12, to 87.5 +/- 3.4%; n = 13; p<0.01) decreased, and both fractional distal reabsorptions--I and II--increased (96.5 +/- 1.5, n = 12, to 97.8 +/- 0.9%; n = 13; p<0.01; and 8.2 +/- 3.5, n = 12, to 12.2 +/- 3.4%, n = 13, p<0.01, respectively). To summarize, in water-loaded conscious rats (2.5 ml/100 body wt.), corn silk aqueous extract is diuretic at a dose of 500 mg/kg body wt. and kaliuretic at doses of 350 and 500 mg/kg body wt. In water-loaded conscious rats (5.0 ml/100 g body wt.), corn silk aqueous extract is kaliuretic at a dose of 500 mg/kg body wt., but glomerular filtration and filtered load decrease without affecting proximal tubular function, Na+, or uric acid excretion.

Ecdisteróide e iridóide glicosilado de Vitex gardneriana Schauer (Verbenaceae) / Ecdysteroid and iridoid glycoside from Vitex gardneriana Schauer (Verbenaceae)

O extrato metanólico das cascas do caule de Vitex gardneriana Schauer forneceu o ecdisteróide, 20-hidroxi-ecdisona e o iridóide glicosilado, aucubina. As estruturas foram caracterizadas por métodos químicos e espectroscópicos.

The methanolic extract of the stem bark of Vitex gardneriana Schauer afforded the ecdysteroid, 20-hydroxy-ecdysone and the iridoid glycoside, aucubin. Their structures were established on the basis of chemical and spectroscopic studies.

Estudo farmacognóstico de Croton rhamnifolius H.B.K. e Croton rhamnifolioides Pax & Hoffm. (Euphorbiaceae) / Pharmacognostic study of Croton rhamnifolius H.B.K. and Croton rhamnifolioides Pax & Hoffm. (Euphorbiaceae)

Aspectos farmacognósticos de Croton rhamnifolius H.B.K. e C. rhamnifolioides Pax & Hoffm. foram comparados. Evocou-se a armacogeografia do gênero em Pernambuco, bem como a farmacoetimologia, farmacoetnologia, farmacobotânica e a farmacoquímica das espécies citadas. Este estudo permitiu localizar os taxa nesse Estado, conhecer seus nomes vulgares e suas utilizações, segundo a população local. Comparou-se também as características botânicas e finalizou-se com um estudo fitoquímico, que evidenciou os protocolos extrativos, e a caracterização dos principais grupos de substância presentes nos dois taxa: polifenóis, terpenóides, alcalóides e açúcares redutores.

The pharmacognostical aspects of Croton rhamnifolius H.B.K. and C. rhamnifolioides Pax & Hoffm. have been compared. The parameters applied for such comparison were the pharmacogeography concerning this genus in Pernambuco, as well as the pharmacoetymology, the pharmacoethnology, the pharmacobotany and the pharmacochemistry, all of which related to both species above mentioned. Not only was the present study able to ascertain the species’ rate regarding the State, but also to determine its medical usage and denomination among the locals. The botanical characteristics were compared and a phytochemical analysis was carried out in order to establish the extractive rocedures and also the main molecule’s rate found on both: terpenoids, alkaloids, polyphenols and reducting sugars.

Pharmacology of Piper marginatum Jacq. a folk medicinal plant used as an analgesic, antiinflammatory and hemostatic.

The pharmacological activities of the water extract of Piper marginatum Jacq. (Piperaceae), a plant reputed in the Brazilian folk medicine for its analgesic/antiinflammatory, hemostatic and skin wound-healing properties, were assessed. Intraperitoneal injection (i. p.) of the extract (0.1 to 1 g/kg) in mice and rats caused piloerection, sialorrhea, lacrimation, muscle relaxation and dyspnea. At doses above 1 g/kg the extract caused respiratory arrest and death. Intravenous injection of the extract (0.1 to 0.5 mg/kg) into anesthetized rats caused a dose-related hypertension (by 27 to 48 %) that was blocked by prazosin (1 mg/kg) and yohimbine (2 mg/kg). Pithing, reserpine treatment and ganglionic blockade with hexamethonium (5 mg/kg) enhanced the effect. Oral treatment of unanesthetized rats and intragastric administration to anesthetized animals also produced hypertension. The sympathomimetic activity of the extract in isolated vas deferens, left atria and mesenteric arterial bed preparations paralleled that of noradrenaline, and was blocked to the same extent as noradrenaline by α-blockers. The plant extract (0.5 and 1 g/kg, p. o.) also reduced carrageenin-induced paw edema in rats by 80 to 90 % of the control, but it had less effect on the volume of exudate and leucocyte migration in carrageenin-induced pleurisy. Likewise, the extract had a small analgesic effect on the acetic acid-induced writhing test in mice. It is concluded that the antiedema effect of the plant extract is mainly related to its vasoconstrictor constituent(s). This sympathomimetic activity may explain the plant's reputed hemostatic properties when applied topically to bleeding skin wounds. The predominant vasoconstrictor component of P. marginatum detected in HPLC analysis was noradrenaline, whose activity is apparently preserved in the crude extract and produces vasoconstriction after oral administration.