12 research outputs found
Three new triterpenes from the resinous bark of Protium kleinii and their antinociceptive activity
Three novel pentacyclic triterpenes have been isolated from the resin of Protium kleinii and their structures elucidated by NMR spectroscopy as 3-oxo-11beta,16beta-dihydroxy-urs-12-ene (1), 3-oxo-11beta-hydroxy-urs-12-ene (2) and 3-oxo-11beta-hydroxy-olean-12-ene (3). The systemic administration of the above compounds (10-100 mg kg-1, i.p.) was able to inhibited both first and second phase of the formalin-induced nociception in mice. The known triterpenes 3beta,16beta-dihydroxy-olean-12-ene (brein) (4) and a mixture of alpha (5)- and beta-amyrin (6) were also found. Três triterpenos pentacíclicos inéditos foram isolados da resina de Protium kleinii. Suas estruturas, 3-oxo-11beta,16beta-diidróxi-urs-12-eno (1), 3-oxo-11beta-hidróxi-urs-12-eno (2) e 3-oxo-11beta-hidróxi-olean-12-eno (3), foram elucidadas por espectroscopia de RMN. A administração sistêmica destes compostos (10-100 mg kg-1, i.p.) foi capaz de inibir tanto a primeira quanto a segunda fase da nocicepção induzida pela formalina em camundongos. Em adição, foram isolados os triterpenos conhecidos 3beta,16beta-dihidróxi-urs-12-eno (breina) (4) e uma mistura de alfa (5)- e beta-amirina (6)
Chemical and pharmacological studies of Phyllanthus caroliniensis in mice
The aim of this study was to isolate and characterize the constituents of the hydroalcoholic extract (HE) of the leaves, stems and roots from P. caroliniensis, and also to evaluate the preliminary antinociceptive action of the HE and purified compounds in mice. Phytosterols, quercetin, gallic acid ethyl ester and geranin were identified in P. caroliniensis on the basis of 1H and 13C NMR spectral data and by mixed co-TLC and co-HPLC injection with authentic samples. The HE of P. caroliniensis (10-100 mg kg-1, i.p.) inhibited, in a dose-related manner, acetic acid-induced abdominal constrictions in mice, with a mean ID50 value of 23.7 mg kg-1. In the formalin test, the HE given intraperitoneally (1-30 mg kg-1) or orally (25-600 mg kg-1) caused graded inhibitions of both the neurogenic (first phase) and the inflammatory response (late phase) of formalin-induced licking. The HE was 54-fold more effective in inhibiting the late phase than it was in inhibiting the first phase of the formalin test, with mean ID50 values of 3.6 and 196.4 mg kg-1, respectively. The HE failed, however, to affect the oedematogenic response associated with the late phase of formalin-induced pain. In addition, the reference drug, aspirin, given intraperitoneally (1-100 mg kg-1) or orally (100-600 mg kg-1), caused significant inhibition of the late but not the first phase of the formalin test. Pharmacological analysis also revealed that quercetin, gallic acid ethyl -1 ester and a semi-purified fraction of flavonoids (1-100 mg kg i.p.) exhibited graded and significant antinociception against acetic acid-induced abdominal constriction. The mean ID50 values (mg kg-1) for these effects were: 18.8, 34.7 and 5.3, respectively. It is concluded that quercetin, gallic acid ethyl ester and some as yet unidentified flavonoids might account for the antinociceptive action reported for the HE of P. caroliniensis
INVESTIGAÇÃO FITOQUÍMICA E AVALIAÇÃO DA ATIVIDADE ANTIBACTERIANA DA Mikania lanuginosa DC (ASTERACEAE)
O presente trabalho envolveu extração, isolamento, purificação e identificação dos constituintes
químicos das partes aéreas da Mikania lanuginosa DC (ASTERACEAE). No processo de extração
ocorreu a formação de um precipitado, no qual foi isolado e purificado um composto majoritário,
que por análises espectroscópicas de IV, RMN 1H, RMN 13C e por comparação com os dados
existentes na literatura, foi identificado como sendo o diterpeno ácido caurenóico. Foram realizados
ensaios biológicos para avaliar a ação antimicrobiana com o precipitado, extrato etanólico bruto,
as frações hexânica, diclorometano, acetato de etila, butanólica e o diterpeno ácido caurenóico
contra as cepas Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus
aureus ATCC 25923, Staphylococcus epidermidis ATCC 12228 e Bacillus cereus, pela técnica da
difusão em meio sólido por cavidade e posteriormente pelo método de diluição em placa. Os
resultados demonstraram que as frações hexânica, diclorometano, acetato de etila, butanólica e
o ácido caurenóico obtidos da M. lanuginosa, apresentaram atividade antimicrobiana moderada
frente as bactérias Gram positivas e foram inativos contra as bactérias Gram negativas.
Phytochemical Investigation and Antimicrobial Activity Evaluation of the Mikania
lanuginosa DC (ASTERACEAE)
Abstract
The present study investigated the extraction, isolation and purification the chemical compounds of
the aerial parts of Mikania lanuginosa DC (ASTERACEAE). In the process of extraction it occurred the
formation of a precipitate, it which was isolated and purified a ruling compound, and by spectroscopic
analysis of the IR, 1H NMR, 13C NMR and comparison with reported data in the literature it was identified
as being the diterpene kaurenoic acid. It were performed biological assays to estimate the
antimicrobial action with the precipited, crude etanolic extract, hexane, dichoromethane, acetate
ethyl, butane fractions and diterpene kaurenoic acid contrasting with strains Escherichia coli ATCC
25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Staphylococcus
epidermidis ATCC 12228 e Bacillus cereus, by technique of the diffusion in solid mean by cavity and
afterwards by the plaque dilution method. The results showed that the hexane, dichoromethane,
acetate ethyl, butane fractions and the kaurenoic acid obtained from the Mikania lanuginosa DC
presented a moderate antimicrobial activity face to Gram positives bacteria and got inert against
the Gram negatives bacteria
Antibacterial activity and phytochemical analysis of Vochysia divergens (Vochysiaceae)
Vochysia divergens Pohl (Vochysiaceae) is a tree commonly found in wet soils of 'Pantanal' of Mate Grosso, Brazil, and used in folk medicine against infections and asthma. We have studied different extracts and some isolated compounds from this plant for antibacterial activity. From the extracts of the stem bark β-sitosterol, betulinic acid and sericic acid were isolated. The minimal inhibitory concentration (MIC) for Staphylococcus aureus were: ethanolic extract (MIC = 1.5 mg/ml); ethyl acetate extract (MIC = 2.0 mg/ml); and sericic acid (MIC = 1.0 mg/ml). Escherichia coli was resistant until 5 mg/ml
Evaluation of the proliferative activity of methanol extracts from six medicinal plants in murine spleen cells
A number of natural compounds have been used as immunomodulatory agents, enabling the function of the immune system to be modified by stimulating or suppressing it. There has been increasing interest in the study of therapeutic action of plant extracts regarding their immunomodulatory activity. The aim of this study was to identify and evaluate the action of extracts of the medicinal plants Calophyllum brasiliense, Ipomoea pes-caprae, Matayba elaeagnoides, Maytenus robusta, Rubus imperialis and Vernonia scorpioides on the development of spleen cells from mice, using the in vitro cellular proliferation assay. The cells, obtained by mechanical rupture of mice spleen (5x10(4) cells/mL), were incubated with methanol extracts (10, 50, 100 and 200 µg/mL) and phytohemagglutinin (PHA, 5 µg/mL). The basal control for proliferation consisted of cells alone, while the positive control consisted of cells and PHA. The cell culture was kept at 37 ºC in 5% CO2 for 72 hours, and cell proliferation was revealed by the blue tetrazolium reduction assay (MTT). The results were expressed as percentage of growth and were analyzed using the Kruskal-Wallis and Mann-Whitney tests. The C. brasiliense, I. pes-caprae and M. elaeagnoides extracts showed dose-dependent induction of cell proliferation, with a significant increase in cell proliferation (pVárias substâncias de origem natural têm sido utilizadas como agentes imunomoduladores, permitindo modificar a função do sistema imune e propiciando o estudo de atividades terapêuticas de extratos de plantas. Este trabalho objetivou identificar a atividade imunomodulatória dos extratos de seis plantas medicinais da flora brasileira, Calophyllum brasiliense, Ipomoea pes-caprae, Matayba elaeagnoides, Maytenus robusta, Rubus imperialis e Vernonia scorpioides, sobre a proliferação de células esplênicas de camundongos. As células esplênicas murinas obtidas por ruptura mecânica do baço (5x14³ células/mL) foram incubadas com os extratos metanólicos das plantas (10, 50, 100, 200 µg/mL) e fito-hemaglutinina (PHA, 5 µg/mL). O controle basal de proliferação foi constituído de células apenas e o controle positivo formado por células e PHA. O cultivo celular foi mantido a 37 ºC, 5% de CO2, 72 horas, com quantificação da proliferação celular pelo ensaio de redução do azul de tetrazólio. Os resultados expressos em percentagem de crescimento foram analisados pelos testes de Kruskal-Wallis e Mann-Whitney. Os extratos de C. brasiliense, I. pes-caprae e M. elaeagnoides mostraram indução dose-dependente da proliferação celular (p<0,03), com percentagem de crescimento de, respectivamente, 88,2%, 73,1% e 52,7%, sugerindo estímulo de linfócitos T. Contrariamente, os extratos de M. robusta, R. imperialis e V. scorpioides apresentaram significância apenas com percentagem de crescimento negativa, indicando inibição da proliferação celular (p<0,04). A continuidade no estudo biomonitorado permitirá a identificação das frações e substâncias isoladas responsáveis pelas atividades imunomoduladoras