Macrophage activation by Paepalanthus spp. extracts

Macrófagos são conhecidos por exercerem uma importante função de mecanismo de defesa quando estas células são estimuladas com produtos naturais e produtos bacterianos (dentre outros). Uma variedade de citocinas e compostos químicos são liberados para induzir sistema de defesa fundamental. Entre outros peróxido de hidrogênio (H2O2) tem sido identificado como moléculas tendo multifunções. Entretanto está bem estabelecido que (H2O2) está envolvido em inúmeros processos fisiológicos, como por exemplo, neurotransmissão, relaxamento da musculatura lisa ou regulação imune. Para a determinação de peróxido de hidrogênio (H2O2) em macrófago peritoneal em camundongos, determinou-se a ação imunomodulatória de extratos (etanólico e etanólico 70%) obtidos de quatro espécies do gênero Paepalanthus (Eriocaulaceae) na concentração de 10 mg/mL. Os estratos etanólicos 70 % de capítulos de P. Hilairei, P. robustus, P. vellozioides e P. speciocus apresentaram maior liberação de (H2O2) do que os outros extratos etanólicos.

Evaluation of extracts from Coccoloba mollis using the Salmonella/microsome system and in vivo tests

The common everyday use of medicinal plants is an ancient, and still very widespread practice, whereby the need for studies on their possible toxicity and mutagenic properties. The species Coccoloba mollis has been much used in phytotherapy, mainly in cases involving loss of memory and stress. In order to investigate its genotoxic and mutagenic potential, ethanolic extracts from the leaves and roots underwent Salmonella/microsome assaying (TA98 and TA100 strains, with and without exogenous metabolism - S9), besides comet and micronucleus tests in vivo.There was no significant increase in the number of revertants/plate of Salmonella strains in any of the analyzed root-extract concentrations, although the extract itself was extremely toxic to the Salmonella TA98 strain in the tests carried out with S9 (doses varying from 0.005 to 0.5 µg/plate). on the other hand, the leaf-extract induced mutations in the TA98 strain in the absence of S9 in the highest concentration evaluated, although at very low mutagenic potency (0.004 rev/µg). Furthermore, there was no statistically significant increase in the number of comets and micronuclei, in treatments involving Swiss mice. It was obvious that extracts of Coccoloba mollis, under the described experimental conditions, are not mutagenic.

Antifungal activity of extracts from Brazilian Cerrado plants on Colletotrichum gloeosporioides and Corynespora cassiicola

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anti-inflammatory and analgesic activities of the crude extracts from stem bark of Bauhinia guianensis

Methylene chloride, ethyl acetate and methanolic extracts front the stem bark of Bauhinia guianensis (Leguminosae, Caesalpinoideae) were obtained. These extracts were evaluated for antiinflammatory activity which was conducted using carrageenin, dextran and histamine-induced paw edema in rats. The extracts of B. guianensis were also assessed for analgesic activity which was conducted using the writhing test in mouse. The different animal groups were treated with these extracts (100 mg/kg i.p. and p.o, IC50) 30 min prior to the application of stimuli. The methanolic extract demonstrated significant inhibition in the carrageenin-induced edema model. In the dextran-induced edema model, all three extracts inhibited the inflammatory process significantly with the methanolic extract being the most active. The ethyl acetate extract was the only one shown to be effective in the histamine-induced edema model. Finally all extracts inhibited effectively the algogenic process in the writhing test induced by acetic acid.

Influence of different extraction methods on the yield and linalool content of the extracts of Eugenia uniflora L.

This work has been developed using a sylvestral fruit tree, native to the Brazilian forest, the Eugenia uniflora L., one of the Mirtaceae family. The main goal of the analytical study was focused on extraction methods themselves. The method development pointed to the Clevenger extraction as the best yield in relation to SFE and Soxhlet. The SFE method presented a good yield but showed a big amount of components in the final extract, demonstrating low selectivity. The essential oil extracted was analyzed by GC/FID showing a large range of polarity and boiling point compounds, where linalool, a widely used compound, was identified. Furthermore, an analytical solid phase extraction method was used to clean it up and obtain separated classes of compounds that were fractionated and studied by GC/FlD and GUMS. (c) 2006 Elsevier B.V. All rights reserved.

Determination of Cd(II) and Cd-metallothioneins in biological extracts using baker's yeast and inductively coupled plasma optical emission spectrometry

The use of Saccharomyces cerevisiae as a sorbent material to separate Cd(II) and Cd-metallothionein complex (Cd-MT) has been explored. Solid-liquid phase extractions were carried out in batch mode and the main parameters of the process (pH, temperature, time of incubation, amount of biomass and analyte) were evaluated. Under optimized conditions, the yeast quantitatively retain (94 +/- 5%) the Cd(II) while 97 +/- 2% of the Cd-MT remain in the supernatant. on base of the findings of this study, a simple method is proposed to determine Cd(II) and Cd-MT in cytosols extracted from mouse kidney and crab hepatopancreas. Inductively coupled plasma optical emission spectrometry was used to quantify the analytes in solid and liquid phase. Determination of Cd in the solid phase was carried out by introducing a slurry of the yeast (0.0625 g/10 mL) directly to the inductively coupled plasma optical emission spectrometer. Mixed standards solutions, which also have been submitted to the extraction procedure, were used to quantify the analytes in the samples. Thus, matrix effects due to nebulization of the slurry were overcame. Limits of detection (3 sigma) for Cd(II) and Cd-MT were 1.5 and 1.2 mu g L-1, respectively. Relative standard deviations of signals were 4.2% for measurements in the slurry of solid phase and 2.1% for measurements in the liquid phase. Recoveries of the analytes in cytosol samples were between 76 and 114%. The concentrations of Cd(II) (2.4 +/- 0.5 mu g L-1) and Cd-MT (3.0 +/- 0.5 mu g L-1) found by using the proposed approach were close to those found by tangential-flow ultrafiltration technique (2.6 +/- 0.7 mu g L-1 for Cd(II) and 3.7 +/- 1.7 mu g L-1 for Cd-MT).

Effect of Mouriri pusa extracts on experimentally induced gastric lesions in rodents: Role of endogenous sulfhydryls compounds and nitric oxide in gastroprotection

Several plants are used in folk medicine to treat gastrointestinal disorders. Mouriri pusa Gardn. (Melastomataceae) is a medicinal plant commonly used in the central region of Brazil against gastric ulcer. Two organic extracts methanolic (MeOH) and dichloromethane (DCM) obtained by sequential extraction from the leaves of Mouriri pusa were evaluated for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH, absolute ethanol, non-steroidal anti-inflammatory drug, stress and pylorus ligature) in mice and rats. The best results were obtained after pretreatment with MeOH extract whereas the DCM extract did not show the same significant antiulcerogenic activity. No acute toxicity was observed in animals treated with 5 g/kg, p.o. of MeOH extract. The mechanism involving the antiulcerogenic action of MeOH extract seemed to be related to NO generation and also suggested the effective participation of endogenous sulfhydryl group in the gastroprotective action. Phytochemical investigation of the MeOH extract of Mouriri pusa yielded tannins, flavonoids and (-)-epicatechin. The presence of these phenolic compounds probably would explain the antiulcerogenic effect of the polar extract of Mouriri pusa leaves. (c) 2006 Elsevier B.V.. All rights reserved.

PHARMACOLOGICAL EVALUATION OF THE INHIBITORY EFFECT OF EXTRACTS FROM ANCHIETIA-SALUTARIS ON THE HISTAMINE-RELEASE INDUCED IN THE RAT AND THE GUINEA-PIG

The tea made with leaves and stems of plant Anchietia salutaris is traditionally used in Brazil to treat allergies. We examined the effects of a crude aqueous extract and of purified fractions of this plant on the histamine release induced in rat and guinea pig tissues. The crude extract (3-10 mu g/ml) inhibits the histamine release induced by compound 48/80 (0.5 mu g/ml) and antigen in rat peritoneal mast cells. The inhibition is significant after 10 s of preincubation and is completed after 3 min. The crude extract dissolved in the perfusion fluid (1-30 mu g/ml) also inhibits the histamine release induced in guinea pig heart by cardiac anaphylaxis and in hearts from pretreated animals (10-100 mg/kg i.p.). In pretreated animals, the effect manifests after 3 h, is maximum after 12 h and disappears after 48 h. The histamine release induced in isolated guinea pig heart by ionophore A23187 is inhibited by similar doses as in antigen-induced histamine release. Extraction with solvents concentrated the active principle (s) in the hexane fractions, as demonstrated by the inhibition of the histamine release induced by antigen in isolated cells from guinea pig heart dispersed with collagenase. In subfractions produced by the fractionation of the hexane fraction, the active principle(s) concentrated in the subfractions obtained by extraction with hexane and ethyl acetate, which shows the low polarity of the compound(s). The same subfractions that inhibit the histamine release induced by antigen in cells from guinea pig heart also inhibit pulmonary cells. Our result show that A. salutaris contains low-polarity compound(s) that inhibit the histamine release induced by three different mechanisms in mast cells from two animal species. These facts suggest that the active principle(s) of A, salutaris could be useful in the treatment of allergies and/or as a tool for the study of mast cell secretions.

Anticlastogenic effect of aqueous extracts of Agaricus blazei on CHO-k1 cells, studying different developmental phases of the mushroom

The Agaricus blazei Murill (ABM) mushroom, known as the sun mushroom, is native to Brazil and has become known for its medicinal properties. This study examined the anticlastogenic effect of Agaricus blazei in Chinese hamster ovary cells, CHO-k1, by means of a chromosome aberration test using methyl methanesulphonate (MMS, 10(-4)M) as the DNA damage inducing agent. Two mushroom lines were used, ABM 99/26 and ABM 97/11, and the latter was used in the young (Y) and sporulating (S) developmental phases. The cells were treated for 12 h with MMS alone or combined with aqueous extracts of A. blazei at a final concentration of 0.15%, which were prepared at three different temperatures: (a) hot (60 degreesC), (b) room temperature (25 degreesC) and (c) chilled (4 degreesC). Mushroom extracts showed a marked anticlastogenic effect against DNA damage, as evidenced by a decrease in the number of cells with breaks, regardless of the line used, or the developmental stage or the temperature at which the extract was prepared. Generally, the extracts were more effective in reducing the isochromatid type breaks. The data obtained suggest that extracts of A. blazei mushroom are anticlastogenic under the conditions tested, mainly during the G1 and S stages of the cell cycle, where chromosome breaks of the isochromatid type are produced by the MMS agent. (C) 2003 Elsevier Ltd. All rights reserved.

Cutaneous hypersensitivity induced in rabbits by extracts of the tick Amblyomma cajennense (Acari : Ixodidae)

The cutaneous hypersensitivity test was used to correlate host resistance to ticks and type of reactions elicited by Amblyomma cajennense (Fabricius, 1787) tick extract in rabbits. Rabbits were divided into 3 groups of 2 animals each: naive, pre-infested and control. Cutaneous hypersensitivity was induced by intradermal inoculation of 25 mug extract in 0.03 rut of phosphate buffered saline (PBS) in rabbit ears. Control rabbits were inoculated with PBS only. The ear thickness was measured with a Mitutoyo(R) device before and 10 min, 1, 2,4,18, 24,48,72 and 96 h post-inoculation (PI). Pre-infested rabbits showed an immediate type reaction within the 1st 10 min PI (60 % increase in ear thickness) and a delayed reaction (18 h) (85 % increase), whereas the naive rabbits showed only the immediate reaction within the 1st 4 h (60 % increase). PBS induced only mild reactions. These results point out the crucial role of the cellular immune response of rabbits in the expression of resistance to A. cajennense.

Allergenic extracts from Metarhizium anisopliae: Obtainment and characterization

Metarhizium anisopliae is used as a biopesticide for insects that damage agricultural plantations like sugar cane and forage plants. In a previous study the sensitization to this fungus of asthmatic patients coming from sugar cane areas was showed. The aims of this work were: to compare crude extracts obtained with Tris-HCl and Coca liquid from several growth phases of M. anisopliae concerning the total content of proteins and their electrophoretic analysis profile; to evaluate in vivo allergic sensitization in Balb/c mice and allergic patients from a sugar cane area, and to characterize the allergenic fractions in the sera of patients positive for the prick test by means of Western-blotting. The extract obtained with Coca liquid on the 16(th) day was the one that presented the greatest number of proteic fractions, including all those present in the other extracts. Twelve fractions were verified in this extract with approximate molecular weights from 94 to 14 kDa. The allergenicity of the extract obtained on the 16(th) day was proven by the production of IgE antibodies in Balb/c mice, with titres of 200. Prick tests carried out with the extract of the 16(th) day in 79 atopic individuals (from sugar cane area), 35 atopic individuals (from urban area) and 11 non- atopic individuals showed respective positivity of 29%, 9% and 0%. The allergenic characterization in vitro was performed by means of Western blotting, and the fractions that reacted with the positive individuals' sera were those of approximate molecular weights of 67 kDa (95%); 20 kDa (55%); 94 kDa (36%); 34 and 36 kDa (23%); 43 and 48 kDa (14%): 16 kDa (9%) and 54kDa (5%). It was concluded that the crude allergenic extract, obtained with Coca liquid from the 16(th) day growth of Metarhizium anisopliae, contains allergenic fractions and can be used in diagnostic screening tests.

Dialysable leukocyte extracts modify the course of experimental paracoccidioidomycosis in the Syrian hamster

The effect of dialysable leukocyte extracts (DLE) obtained from hamsters immunized with Paracoccidioides brasiliensis (immune DLE) and from non-immunized hamsters (non-immune DLE) was studied in hamsters inoculated with P. brasiliensis by the intratesticular route. Treatment with immune or non-immune DLE was started during the third week of infection and was repeated at 7, 11, 15 and 19 weeks. A group of untreated infected animals was used as control. Animals were submitted to the delayed hypersensitivity skin test to P. brasiliensis antigen (PbAg) in vivo and assayed in vitro by the macrophage migration inhibition test in the presence of Phytohemagglutinin (PHA) and PbAg and by immunodiffusion for specific antibody. The animals were sacrificed at 4, 8, 12, 16 and 20 weeks. The morphology and extension of the lesions were studied at the inoculation site, and in lymph nodes, lungs, liver, spleen and kidneys. In contrast to the controls, animals treated with both DLEs maintained a positive cell-mediated immune response throughout the experiment and developed less extensive infection with a significantly lower number of fungi in the lesions. The results suggest that immune and non-immune DLE preparations modified the evolution of experimental paracoccidioidomycosis with equal efficiency. This similarity may be explained by the immunoregulatory activities of both extracts.

Global yields, chemical compositions and antioxidant activities of clove basil (Ocimum gratissimum L.) extracts obtained by supercritical fluid extraction

Clove basil (Ocimum gratissimum) extracts were obtained with supercritical CO2. Clove basil was cultivated using 0, 4, 8 and 12 kg/m(2) of organic fertilizer and was harvested in four seasons: winter, spring, summer and autumn, in the Southern Hemisphere. The extracts' global yields were determined at 40C and 150 bar for samples from all cultivation conditions and harvesting seasons. For selected samples, the extracts' global yields at 40C were determined for pressures of 100, 150, 200, 250 and 300 bar. The extracts were analyzed by gas chromatography-flame ionization detector. Antioxidant activity (AA) was assessed using the coupled reaction of beta-caroteneand linolenic acid. The extracts' global yields varied from 0.91 to 1.79% (dry basis), and the AAs varied from 62 to 84% compared with the control beta-carotene. Eugenol and beta-selinene were the major compounds. The relative proportion of eugenol varied from 35 to 60%, while the content of beta-selinene remained approximately constant (11.5-14.1%, area). The other substances quantified in the extracts were 1,8 cineole, trans-caryophyllene and alpha-selinene.

In vitro allelopathic effects of extracts and amenthoflavone from Byrsonima crassa (Malpighiaceae)

Extracts and pure amenthoflavone isolated from Byrsonima crassa (Malpighiaceae), a shrub growing in the semi-arid region of Brazil Cerrado, were evaluated in vitro, at different doses, for their effects on tomato seed germination and subsequent growth of seedlings. A hydromethanolic extract showed general stimulatory effects. The EtOAc extract stimulated root elongation and root weight of tomato; shoot elongation was inhibited, while shoot weight was not altered. The pure amenthoflavone isolated from the plant, stimulated shoot elongation at concentrations ranging between 10(-4) M and 10(-6) M.