Hypoglycemic Effect of the Methanol flower Extract of Piper Claussenianum and the Major Constituent 2',6'-dihydroxy-4'-methoxychalcone in Streptozotocin Diabetic Rats.

Piper claussenianum inflorescences crude methanol extract was tested for hypoglycemic effect in streptozotocin-induced diabetic rats. The blood glucose levels of rats treated with methanol extract were reduced from 318.4±28.1 mg/dl before treatment to 174.2±38.3 mg/dl after 12 days of treatment (P<0.05). Phytochemical studies were carried out on inflorescences methanol crude extract in order to investigate the possible metabolites responsible for the pharmacological properties of the extract. After chromatographic procedures, three flavonoids were isolated and characterized. The major compound 2',6'-dihydroxy-4'-methoxychalcone was also tested. Rats that received the chalcone content also displayed a reduction in blood glucose levels from 277.4±7.7 mg/dl before treatment to 158.8±9.2 mg/dl after 12 days of treatment (P<0.05). The results suggest this chalcone is one of the metabolite responsible for the blood glucose levels reduction in rats with streptozotocin-induced diabetes. The inflorescence crude extract of P. claussenianum was found to be composed mainly by flavonoids and may be a potential natural source of compounds with hypoglycemic properties.

Screening antimycobacterial activity of Baccharis dracunculifolia, Centella asiatica, Lantana camara and Pterodon emarginatus / Atividade anti-micobacteriana de Baccharis dracunculifolia, Centella asiatica, Lantana camara e Pterodon emarginatus

ABSTRACT The permanent investigation of new antimycobacterial drugs is necessary for the eradication programs of tuberculosis and other mycobacterium-related diseases. The aim of the present study is to search for new sources of antimycobacterial drugs using plant materials. In this study, 11 plant materials (extracts, essential oils and some fractions) obtained from 4 species of medicinal plants traditionally used as general therapeutics for different illnesses and specifically as treatment of tuberculosis, were evaluated using the microplate resazurin assay against 2 species of the Mycobacterium tuberculosis Complex and 3 nontuberculous mycobacteria. The results showed the hexane extract and the essential oil from fruits of Pterodonemarginatus (Vogel) as potential sources of antimycobacterial drugs against 4 species of tested mycobacteria. The hexane fraction of methanol extract from leaves of Centella asiatica also presented significant mycobacterial growth inhibition, but against M. chelonae only. In conclusion, it was possible to contribute to the antimycobacterial investigations by presenting three new samples of plants with significant antimicrobial activity against four Mycobacteriumspp and suggest future studies about the antimycobacterial properties of fruits from P. emarginatus.

RESUMO A investigação permanente de novas drogas antimicobacterianas é necessária no programa de erradicação da tuberculose e de outras doenças relacionadas com micobactérias. O objetivo deste estudo foi buscar novas fontes de drogas antimicobacterianas usando material vegetal. Neste estudo, 11 materiais de base vegetal (extratos, óleos essenciais e algumas frações) foram avaliados contra 5 espécies de micobactérias. Estes materiais foram obtidos a partir de 4 espécies de plantas medicinais tradicionalmente utilizadas como terapêutica geral para diferentes doenças e, especificamente, no tratamento de tuberculose (Baccharis dracunculifolia, Centella asiatica, Lantana camara, Pterodon emarginatus). Os ensaios foram realizados em microplacas com resazurina contra duas espécies do Complexo Mycobacteriumtuberculosis e 3 espécies de micobactérias não tuberculosas. Os resultados mostraram o extrato hexânico e o óleo essencial de frutos de P.emarginatus como potenciais fontes para drogas antimicobacterianas contra quatro espécies de micobactérias testadas. A fração hexânica do extrato metanólico das folhas de C. asiatica também apresentou significativa inibição do crescimento de micobactérias apenas contra M.chelonae. Em conclusão, foi possível contribuir para as investigações de antimicobacterianos por apresentar três novas amostras de plantas com atividade antimicrobiana significativa contra quatro Mycobacterium spp e sugerir a realização de estudos futuros sobre as propriedades antimicobacterianas de frutos de P. emarginatus.

A novel nerolidol-rich essential oil from Piper claussenianum modulates Candida albicans biofilm.

Candidiasis is a major opportunistic fungal infection in humans, and its incidence has increased steadily over the last two decades. Candida albicans, the main species of the genus, has a large arsenal of virulence attributes that contribute to successful infections, such as dimorphism and biofilm formation. The adverse effects of eukaryotic antimicrobial therapies associated with an increase in resistance to the compounds presently available have boosted efforts to improve the therapeutic arsenal against candidiasis with a newer and cheaper range of drugs. In this study, a novel nerolidol-rich essential oil (EO) derived from Piper claussenianum (Miq.) C. DC., Piperaceae, was tested on the growth, transition (yeast to hyphae), formation and stability of biofilms produced by C. albicans. Both inflorescence and leaf EOs were evaluated and revealed MIC values ranging from 0.04 to 0.1 % and 0.2 to 1.26 %, respectively. Furthermore, leaf EO managed to downregulate the yeast-to-hyphae transition by 81 %, as well as reducing biofilm formation by about 30 and 50 % after incubation for 24 and 48 h, respectively. The EO was also able to reduce the viability of pre-formed biofilm by 63.9 %. Finally, the association between the leaf EO and fluconazole was evaluated and revealed an interesting synergistic effect. Taken together, these results demonstrate that this novel compound could be a promising agent and could reinforce the arsenal of therapeutic alternatives for the treatment of candidiasis. Furthermore, it may represent a novel and natural source of nerolidol, which could be of interest pharmaceutically.

Chemosystematics of the rosiflorae.

The superorder Rosiflorae (sensu Dahlgren, 1980) belongs to the Angiospermae. It comprises twelve orders and thirty-eight families formed of species with varied habits widely distributed in temperate regions. The chemistry of Rosiflorae species is highly diversified; nevertheless it shows clearly phylogenetic affinity among the orders, except for Buxales. Flavonoids and triterpenoids are the real taxonomic markers for the superorder, due not only to the great number of occurrences, but also to the high structural diversity. On the other hand, the alkaloids are suitable as chemical markers only for the order Buxales. For orders and families of Rosiflorae, analysis of correlations among chemical parameters based on flavonoids and triterpenoids, with themselves and with the morphological and chemo-morphological parameters, showed evolutionary gradients among these taxa in which Trochodendrales occupy a primitive position while Saxifragales have the outpost. According to the types of flavonoids found in the superorder, there is clearly a higher incidence of flavonols than flavones, suggesting a primitive status of the Rosiflorae. Evolutionary advancement parameters relative to flavonoid hydroxyl protection show preferential protection mechanisms of glycosylation against methylation as well as a high percentage of free hydroxyl groups. The order Buxales has an isolated position in the superorder Rosiflorae with a high alkaloid production, which is quite exclusive to this taxon.

Chemosystematics of the Rosiflorae / Quimiossistemática de Rosiflorae

The superorder Rosiflorae (sensu Dahlgren, 1980) belongs to the Angiospermae. It comprises twelve orders and thirty-eight families formed of species with varied habits widely distributed in temperate regions. The chemistry of Rosiflorae species is highly diversified; nevertheless it shows clearly phylogenetic affinity among the orders, except for Buxales. Flavonoids and triterpenoids are the real taxonomic markers for the superorder, due not only to the great number of occurrences, but also to the high structural diversity. On the other hand, the alkaloids are suitable as chemical markers only for the order Buxales. For orders and families of Rosiflorae, analysis of correlations among chemical parameters based on flavonoids and triterpenoids, with themselves and with the morphological and chemo-morphological parameters, showed evolutionary gradients among these taxa in which Trochodendrales occupy a primitive position while Saxifragales have the outpost. According to the types of flavonoids found in the superorder, there is clearly a higher incidence of flavonols than flavones, suggesting a primitive status of the Rosiflorae. Evolutionary advancement parameters relative to flavonoid hydroxyl protection show preferential protection mechanisms of glycosylation against methylation as well as a high percentage of free hydroxyl groups. The order Buxales has an isolated position in the superorder Rosiflorae with a high alkaloid production, which is quite exclusive to this taxon.

A superordem Rosiflorae (sensu Dahlgren, 1980), Angiospermae, é composta por doze ordens e trinta e oito famílias. Em geral são plantas de hábito variado e muito freqüentes em regiões temperadas. A química das espécies de Rosiflorae é muito diversificada, mas evidencia a proximidade filogenética entre as ordens, com exceção de Buxales. Os flavonóides e os triterpenóides mostram-se como verdadeiros marcadores quimiossistemáticos em nível de superordem, devido, não somente ao seu grande número de ocorrências, mas também pela sua elevada diversidade estrutural; contudo os alcalóides são os marcadores para Buxales. Avaliação das correlações dos parâmetros químicos entre si e com os parâmetros morfológico e químico-morfológico, para ordens e famílias de Rosiflorae, com base nos seus flavonóides e triterpenóides, evidenciaram uma grande proximidade filogenética entre esses táxons, além de mostrar gradientes evolutivos, em que Trochodendrales e Saxifragales são posicionadas como a ordem mais primitiva e a ordem mais evoluída, respectivamente. Com relação aos tipos flavonoídicos produzidos na superordem, verifica-se uma maior produção de flavonóis em relação às flavonas, o que acarreta uma baixa relação favona/flavonol, confirmando o posicionamento primitivo da superordem, indicado pelos índices morfológico e químico-morfológico. A proteção das hidroxilas flavonoídicas mostra uma nítida preferência na proteção por glicosilação e desproteção em detrimento à proteção por metilação. A ordem Buxales praticamente encontra-se isolada na superordem com grande produção de alcalóides muito característicos, sendo bastante diferenciada da produção alcaloídica relativamente pobre da superordem.

Anti-inflammatory and anti-ulcerogenic properties of Stachytarpheta cayennensis (L.C. Rich) Vahl.

In the present work, the anti-inflammatory and gastroprotective properties of ethanolic extracts of Stachytarpheta cayennesis (L.C. Rich) Vahl (Verbenaceae) were assessed. Chromatographic analysis of the crude ethanolic extract, SC01, revealed high concentrations of the iridoid ipolamiide, whereas the SC02, the second ethanolic extract, presented the arylpropanoid verbacoside as a major constituent. The oral administration of SC01 (100 mg/kg) into Swiss mice failed to inhibit paw oedema and pleural exudation induced by carrageenan and zymosan, whereas SC02 (100 mg/kg, p.o.) inhibited oedema and protein extravasation in all instances. Both extracts inhibited total leukocyte accumulation into the pleural cavity 4 and 24h after the intrathoracic (i.t.) injection of carrageenan, due to the inhibition of neutrophil and mononuclear cell influx, whereas only SC02 was able to inhibit leukocyte mobilization induced by zymosan (100 microg/cavity, i.t.). SC02 inhibited LPS (250 ng/cavity)-induced total leukocyte, neutrophil and eosinophil accumulation in the pleural cavity, whereas SC01 selectively inhibited neutrophil influx. In addition, our data indicates that the extract SC02 presents an important anti-ulcerogenic activity, since it inhibited diclofenac-induced (100 mg/kg, p.o.) gastric ulcera. Overall, these data provide evidence for the anti-inflammatory and gastroprotective properties of Stachytarpheta cayennensis, supporting its use in folk medicine for such purposes.

Topical antiinflammatory and analgesic activities of Copaifera duckei dwyer.

The oleoresin of several Copaifera species is used widely in the Amazonian Region mainly as a topical antiinflammatory and healing agent. The topical analgesic and antiinflammatory activities of Copaifera duckei oleoresin, whose terpenoidal chemical composition has been characterized, are now examined. Antiinflammatory activity was evaluated in rats using the carrageenin-induced paw edema and the granuloma tests, and in mice by the croton oil-induced dermatitis test. Analgesic activity was determined in mice using the writhing test method. In the carrageenin-induced edema and granuloma tests the oleoresin in a dose of 1,802 mg/kg inhibited the edema by 18% and granuloma by 42% (p < 0.05), this last result similar to that observed with dexamethasone. Topical doses of 517 mg/kg, 1,035 mg/kg and 1,802 mg/kg produced 52%, 58% and 62% (p < 0.05) reduction of the edema induced by croton oil, respectively, and 48%, 56% and 65% inhibition of the writhing process (p < 0.05). These results suggest that the Copaifera duckei oleoresin has topical antiinflammatory and analgesic activities.

Atividade antimicrobiana dos frutos de Syagrus oleracea e Mauritia vinifera / Antimicrobial activity of Syagrus oleracea and Mauritia vinifera fruits

As espécies pertencentes à família Palmae são muito interessantes do ponto de vista químico e farmacológico. Neste trabalho, foram estudados os frutos de duas espécies da família Palmae, Syagrus oleracea e Mauritia vinifera. Essas palmeiras foram escolhidas por serem espécies brasileiras, abundantes em nosso país, utilizadas popularmente no tratamento de algumas doenças e ainda pouco estudadas. Foram realizados ensaios farmacológicos para avaliação da atividade antimicrobiana dos extratos dos frutos das duas espécies em estudo. Para o teste de atividade antimicrobiana foram utilizadas cepas de bactérias Gram positivas e Gram negativas. A metodologia empregada foi a de Microdiluição em caldo. Foram testados os extratos etanólicos brutos do epicarpo/mesocarpo de S. oleracea e de M. vinifera, o extrato hexânico das amêndoas de S. oleracea, as partições hexânicas e em acetato de etila do epicarpo/mesocarpo de S. oleracea, do epicarpo/mesocarpo e mesocarpo/endocarpo de M. vinifera, na concentração de 100 mg/ml. Os extratos lipofílicos de S. oleracea apresentaram os melhores resultados para essa espécie. Nos testes realizados com M. vinifera, as partições lipofílicas foram as mais inibitórias para a cepa de S. aureus.

Palmae species are very interesting by the chemical and pharmacological points of view. Two species belonging to this family were chosen to initiate the chemical and pharmacological approach of their fruits: Syagrus oleracea (Martius) Beccari and Mauritia vinifera Martius, known in Brazil as Guariroba and Buriti, respectively. Those palm species can be found in several regions of Brazil, especially at the northeast and southeast of the country. They have been used in folk medicine to treat some diseases, however no toxicological and pharmacological studies have been done so far. For the two studied fruits, the antimicrobial activity tests were carried out by broth microdilution methodology. The objective of this work was to contribute for the pharmacological study of palm species, evaluating the antimicrobial activity of the extracts obtained from the fruits of S. oleracea and M. vinifera. The assays evaluated ethanol extracts of the epicarp/mesocarp of S. oleracea and epicarp/mesocarp of M. vinifera; hexane extract of the endosperm of S. oleracea; hexane and ethyl acetate fractions of the epicarp/mesocarp of S. oleracea, epicarp/mesocarp of M. vinifera and mesocarp/endocarp of M. vinifera. The lipophilic extracts of S. oleracea obtained the best results for the species. For M. vinifera, the lipophilic partitions have shown a high inhibitory percentage for S. aureus.

Antinociceptive effect of Nidularium procerum: a Bromeliaceae from the Brazilian coastal rain forest.

Nidularium procerum, a common plant of the Brazilian flora, has not yet been studied for its pharmacological properties. We report here that extracts of N. procerum show both analgesic and anti-inflammatory properties. Oral (p.o.) or intraperitoneal (i.p.) administration of an aqueous crude extract from leaves of N. procerum (LAE) inhibited the writhing reaction induced by acetic acid (ED50 value = 0.2 mg/kg body weight, i.p.) in a dose-dependent manner. This analgesic property was confirmed in rats using two different models of bradykinin-induced hyperalgesia; there was 75% inhibition of pain in the modified Hargreaves assay, and 100% inhibition in the classical Hargreaves assay. This potent analgesic effect was not blocked by naloxone, nor was it observed in the hot plate model, indicating that the analgesic effect is not associated with the activation of opioid receptors in the central nervous system. By contrast, we found that LAE (0.02 microg/ml) selectively inhibited prostaglandin E2 production by cyclooxygenase (COX)-2, but not COX-1, which is a plausible mechanism for the analgesic effect. A crude methanol extract from the leaves also showed similar analgesic activity. An identical extract from the roots of N. procerum did not, however, block acetic acid-induced writhes, indicating that the analgesic compounds are concentrated in the leaves. Finally, we found that LAE inhibited an inflammatory reaction induced by lipopolysaccharide in the pleural cavity of mice.

Antileishmanial activity of isolated triterpenoids from Pourouma guianensis.

The inhibiting activity of triterpenoids isolated from the methanolic extract of Pourouma guianensis (Moraceae) leaves is described for promastigotes and intracellular amastigotes of Leishmania amazonensis. Whereas the fractions containing apigenin, friedelin, epi-friedelinol, arjunolic acid, hyptatic acid B, stigmasterol and sitosterol were of no or relatively low inhibitory activity, fractions containing tormentic acid, 2alpha,3beta-dihydroxyursan-12-en-28-oic acid, 2alpha,3beta-dihydroxyolean-12-en-28-oic acid, oleanolic acid and ursolic acid were very potent in inhibiting promastigote growth at 100 microg/ml. Of the eleven isolated compounds, however, only ursolic acid and oleanolic acid showed high activity against intracellular amastigotes (IC50 value = 27 microg/ml and 11 microg/ml, respectively), which was superior to the control drug Glucantime (IC50 value = 83 microg/ml). The antileishmanial activity of oleanolic acid was directed against the parasite and not due to activation of nitric oxide intermediates by macrophages, but this triterpenoid also significantly inhibited the phagocytic capacity of those cells at concentrations above 40 microg/ml, indicating a cytotoxic effect. These results indicate that Pourouma guianensis contains many triterpenoids and some, such as ursolic and oleanolic acids, may serve as lead compounds for new antileishmanial drugs, but chemical modifications may be necessary to avoid unselective cytotoxicity.

Atividades antinociceptiva e antiinflamatória do óleo essencial de cascas de Duguetia lanceolata St. Hil., Annonaceae

O presente trabalho avaliou as atividades antinociceptiva e antiinflamatória do óleo essencial de cascas de Duguetia lanceolata. Para isto, foram realizados os testes de contorções abdominais induzidas por ácido acético; tempo da lambida da pata induzida por formalina; e edema de pata induzido por carragenina. O número de contorções abdominais (DE50 = 21,79 mg/kg) e o tempo da lambida da pata 1ª fase (DE50 = 5,27 mg/kg) e 2ª fase (DE50 = 1,43 mg/ kg) foram reduzidos significativamente de forma dependente da dose. O material vegetal nas doses de 50, 100 e 200 mg/kg diminuíram de maneira expressiva o edema de pata em 20,83; 36,46 e 48,96 por cento, respectivamente. O óleo essencial de cascas de D. lanceolata possui efeitos antinociceptivo e antiinflamatório por prováveis ações central e periférica.

The present work evaluated the antinociceptive and anti-inflammatory activities of the essential oil from barks of Duguetia lanceolata. For this purpose, acetic acid writhing, formalin and carrageenan tests were performed. The number of writhings (ED50 = 21,79 mg/kg) and the lick of the paw 1st phase (ED50 = 5,27 mg/kg) e 2nd phase (ED50 = 1,43 mg/kg) reduced significantly in a dosedependent form. The doses 50, 100 and 200 mg/kg reduced the paw edema significantly in 20,83; 36,46 and 48,96 percent, respectively. These results suggest that the essential oil from barks of D. lanceolata has antinociceptive and anti-inflammatory effects and probably the mechanisms(s) involve central and peripheric actions.

Immunomodulatory activity of Mollugo verticillata L.

This article describes the evaluation of immunomodulatory activity of Mollugo verticillata L. (Molluginaceae), a weed plant common in warm and/or wet regions of the American continent. Nitric oxide (NO) release was evaluated in mice peritoneal cell cultures treated in vivo using the ethanolic extract of M. verticillata with and without BCG. The plant extract showed immunostimulatory activity when peritoneal cells were stimulated in vitro with BCG antigen only. However, mice peritoneal cells treated with M. verticillata plus BCG showed a drastic reduction in NO production when they received the additional stimulus in vitro with BCG. Ethanolic extracts of M. verticillata could directly increase NO release by peritoneal cells, but suppress the immune response of these cells when treated with BCG antigen and Mycobacterium tuberculosis whole antigen (TB). Preliminary phytochemical tests allowed the detection of quercetin and triterpenoid glycosides in the ethanolic extract of M. verticillata, and those compounds are probably responsible for the effect of this plant material on the immune system.

High-speed countercurrent chromatography as a valuable tool to isolate C-glycosylflavones from Cecropia lyratiloba Miquel.

A new apigeninglycoside, apigenin 6-C-galactosyl-6"-O-beta-galactopyranoside (1), isoorientin, and a mixture of orientin and isovitexin were isolated from leaves of Cecropia lyratiloba by high-speed countercurrent chromatography using a solvent system containing ethyl acetate, butanol, methanol and water. The structural elucidation of 1 was based on NMR spectroscopy.

Flavonoids as chemotaxonomic markers for Asteraceae.

Flavonoids have been shown to be good taxonomic markers for Asteraceae. More than 800 compounds comprising 4700 flavonoid occurrences were included in a computational system specially made for chemotaxonomic purposes. Some implications of flavonols, flavones and other types as well as structural features of them are discussed for tribes and subtribes of Asteraceae.