Bisbenzylisoquinoline Alkaloids of Cissampelos Sympodialis With in Vitro Antiviral Activity Against Zika Virus.

In search of new antiviral compounds against Zika virus we conducted a bioassay-guided fractionation of bisbenzyilisoquinoline alkaloids isolated from Cissampelos sympodialis (Menispermaceae), a medicinal plant species endemic to Brazil. Six subfractions were obtained from a tertiary alkaloidal fraction of the rhizomes (TAFrz) using preparative high-performance liquid chromatography. All the subfractions were tested against Zika virus-infected Vero cells as the cellular model to evaluate cytotoxicity and antiviral effective concentrations. The results showed that three of the six TAFrz subfractions tested were active. The most active ones were the subfraction 6 (that consisted of the alkaloids methylwarifteine and warifteine present as a mixture at a ratio of 8.8:1.2 respectively) and the subfraction 5, that was later identified as warifteine, the major tertiary alkaloid of this species. Warifteine was able to significantly reduce virus titer in Zika virus-infected Vero cells with an IC50 of 2.2 µg/ml and this effect was selective (selectivity index, SI = 68.3). Subfraction 6 had an IC50 = 3.5 µg/ml and was more cytotoxic than pure warifteine, with SI = 6.14. Fraction 5 and fraction 6 were more potent in decreasing the viral titer of Zika virus-infected Vero cells than 6-methylmercaptopurine riboside (IC50 = 24.5 µg/ml and SI = 11.9), a mercaptopurine riboside with ZIKV antiviral activity used as a positive control. Our data demonstrate that alkaloids of the bisbenzylisoquinoline type may be explored as new antiviral agents or as an useful pharmacophore for investigating ZIKV antiviral activity.

Sidastrum paniculatum (L.) Fryxell (Malvaceae): A Promising Source of Bioactive Sulfated Flavonoids Against Aedes aegypti L.

Aedes aegypti L. is known as the most relevant vector mosquito for viruses such as yellow fever, chikungunya, dengue, and Zika, especially in places with unplanned urbanization, and erratic water supply. Plants used in folk medicine have become a useful source of active compounds with the potential to control the dissemination of Ae. aegypti. Compounds isolated from Malvaceae sensu lato have been previously reported as larvicides, repellents, and insecticides. Recent studies have demonstrated the anti Ae. aegypti activity of sulfated flavonoids, an uncommon type of flavonoid derivatives. This research reports the phytochemical investigation of Sidastrum paniculatum (L.) Fryxell, a Malvaceae species with the potential against Ae. aegypti. Chromatographic procedures resulted in the isolation of the compounds: stearic acid (1), N-trans-feruloyltyramine (2), acacetin (3), apigenin (4), tiliroside (5), along with the sulfated flavonoids: wissadulin (6), 7,4'-di-O-methyl-8-O-sulfate flavone (7), yannin (8), beltraonin (9a), 7-O-sulfate isoscutellarein (paniculatumin) (9b), and condadin (10). This is the first report of compound 7-O-sulfate isoscutellarein (9b). The structures were elucidated by spectroscopic analysis (NMR, LC-HRMS and FT-IR). The sulfated flavonoids identified were submitted to a ligand-based and structure-based virtual screening against two targets: 1YIY (from adult Ae. aegypti) and 1PZ4 (from Ae. aegypti larvae). The results indicated that when the O-sulfate group is bearing the position 7, the structures are potentially active in 1PZ4 protein. On the other hand, flavonoids with the O-sulfate group bearing position 8 were showed to be more likely to bind to the 1YIY protein. Our findings indicated that S. paniculatum is a promising source of sulfated flavonoids with potential against Ae. aegypti.

Bisbenzylisoquinoline alkaloids of Cissampelos sympodialis with antiviral activity against dengue virus.

A number of bisbenzyilisoquinoline alkaloids have been previously isolated from Cissampelos sympodialis (Menispermaceae). The tertiary alkaloid fraction of the rhizomes (TAFrz) was prepared and the major alkaloid warifteine was isolated. Five TAFrz subfractions in addition to warifteine were tested against Dengue virus (DENV). We then used an epithelial (Vero) cell line to evaluate the cytotoxicity and effective concentrations of the samples against DENV. All TAFrz subfractions were active, but subfraction 6 (a mixture of the alkaloids methylwarifteine and warifteine) in particular showed a promising antiviral effect against DENV-2 with an IC50 of 2.00 µg/mL and a selectivity index (SI) of 10.74. Warifteine was the second most active sample and had an IC50 of 8.13 µg/mL and SI = 10.94. The antiviral activity of the samples compared favorably with that of 6-methylmercaptopurine riboside (IC50 = 7.31 µg/mL and SI = 11.8). These results suggest that bisbenzylisoquinoline alkaloids may prove interesting leading antiviral compounds.

Effects of L-Carnitine on Equine Semen Quality During Liquid Storage.

l-Carnitine (LC) plays a key role in sperm metabolism, easily providing energy through ß-oxidation, which positively affects motility. The objective of this study was to investigate the association between blood plasma and seminal plasma LC levels, as well as the effect of LC as an additive in a skimmed milk-based extender during sperm storage at 5°C. In the first experiment, semen and blood samples from 14 Quarter Horse stallions were used. The LC content in blood plasma and seminal plasma was determined by spectrophotometry and their relationships with seminal parameters were evaluated. In the second experiment, ejaculates (n = 16) from four Quarter Horses were used. Each ejaculate was split into four treatment groups with different LC concentrations: 0 (control), 0.5, 1.0, and 2.0 mM. Sperm motility, integrity of plasma and acrosomal membranes, intracellular reactive oxygen species content, and plasma membrane stability were evaluated immediately after samples reached 5°C (0 hour) and after 24, 48, and 72 hours. There was a positive correlation (p < 0.05) between LC levels in seminal plasma with both sperm concentration and plasma and acrosomal membrane integrity. Furthermore, the addition of LC (1 and 2 mM) preserved the motility of equine sperm stored at 5°C. It was concluded that the concentrations of LC with seminal plasma present correlate to semen parameters and the addition of LC to skimmed milk-based extender preserves the motility of equine sperm stored at 5°C for up to 48 hours.

Effect of hydroxyamines derived from lapachol and norlachol against Staphylococcus aureus strains carrying the NorA efflux pump.

Isolated substances and those organically synthesized have stood out over the years for their therapeutic properties, including their antibacterial activity. These compounds may be an alternative to the production of new antibiotics or may have the ability to potentiate the action of preexisting ones. In this context, the objective of this study was to evaluate the in vitro antibacterial and efflux pump inhibitory activity of hydroxyamines derived from lapachol and norlachol, more specifically the compounds 2-(2-Hydroxyethylamino)-3-(3-methyl-2-butenyl)-1,4 dihydro-1,4-naphthalenedione, 2-(2-Hydroxyethylamino)-3-(2-methyl-propenyl)[1,4]naphthoquinone and 2-(3-Hydroxypropylamino)-3-(3-methyl-2-butenyl)-[1,4]naphthoquinone, against Staphylococcus aureus strains carrying the NorA efflux pump mechanism. The substances were synthesized from 2-hydroxy-quinones, lapachol and nor-lapachol, obtaining the corresponding 2-methoxylated derivatives via dimethyl sulfate alkylation in a basic medium, which then reacted chemoselectively with 2-ethanolamine and 3-propanolamine to form the corresponding amino alcohols. All three molecules underwent a virtual structure-based analysis (docking). The antibacterial activity of the substances was measured by determining their Minimum Inhibitory Concentration (MIC) and a microdilution assay was performed to verify efflux pump inhibition using the substances at a sub-inhibitory concentration. The results were subjected to statistical analysis using an analysis of variance (ANOVA) followed by Bonferroni's post hoc test. The substances obtained MIC values ≥1024 µg/mL, however, a significant reduction of their MICs was observed when the substances were associated with norfloxacin and ethidium bromide, with this effect being attributed to efflux pump inhibition. Following a virtual analysis based on its structure (docking), information regarding the affinity of new ligands for the ABC efflux pump were observed, thus contributing to the understanding of their mechanism of molecular interactions and the discovery of functional ligands associated with a reduction in bacterial resistance.

In silico evaluation of the antibacterial and modulatory activity of lapachol and nor-lapachol derivates.

The aim of this research was to investigate the pharmacological properties of 2-(2-hydroxyethylamine)-3-(3-methyl-2-butenyl)-1,4-dihydro-1,4-naphthalenedione, 2-(2-hydroxy-ethylamine)-3-(2-methyl-propenyl)-[1,4]naphthoquinone and 2-(3-hydroxy-propylamine)-3-(3-methyl-2-butenyl)-[1,4]naphthoquinone using computational prediction models, in addition to evaluating the in vitro antibacterial and modulatory activity of these compounds against bacterial ATCC strains and clinical isolates. The substances were synthesized from 2-hydroxy-quinones, lapachol and nor-lapachol obtaining the corresponding 2-methoxylated derivatives via dimethyl sulfate alkylation in a basic medium, these then reacted chemoselectively with 2-ethanolamine and 3-propanolamine to form the corresponding amino alcohols. The antibacterial activity and modulatory activity of the substances were assayed by broth microdilution method to determine the Minimum Inhibitory Concentration (MIC). The molecular structures were analyzed using the ChEMBL database to predict possible pharmacological targets, which pointed to the molecule 2- (2-hydroxy-ethylamine)-3-(2-methyl-propenyl)-[1,4]naphthoquinone as a probable antibacterial agent for the proteins Replicative DNA helicase and RecA. The compounds had a low molecular weight and a small number of rotatable bonds. The MICs of the substances were not clinically significant, however, the association with gentamicin and amikacin reduced the MICs of these antibiotics. In conclusion, the combination of these substances with aminoglycosides may be a therapeutic alternative to bacterial resistance and the reduction of side effects.

Antimicrobial activity of propolis extract fractions against Staphylococcus spp. isolated from goat mastitis / Atividade antimicrobiana de frações do extrato de própolis frente à Staphylococcus spp. isolados de mastite caprina

The indiscriminate use of antibiotics in the treatment of caprine mastitis causes the appearance of resistant microorganisms, besides leaving residues in milk, putting at risk to human health. In this way, propolis is an alternative in the treatment of diseases because it has antimicrobial activity, mainly because of the presence of flavonoids in its composition. The aim of this study was to evaluate the antimicrobial potential of propolis to Staphylococcus spp. Isolated from cases of goat mastitis and qualify the crude ethanoic extract by high performance liquid chromatography (HPLC). In this study, the minimum bactericidal concentration values of propolis extracts in ethanol, ethyl acetate and hexane showed that the best concentrations capable of promoting the highest mortality of the isolates of Staphylococcus spp. from mastitis in goats, were 6250, 3125 and 1562.5µg/mL, respectively. By the microplate adherence test, it was found that 20.78% isolates were not able to form biofilm, 14.70% were classified as moderate and 64.70% were weak and none as a strong biofilm producer. Propolis in its different diluents was able to affect the formation of biofilm and showed a pronounced marked antimicrobial activity against Staphylococcus spp. strains and may be indicated for use in in vivo studies.(AU)

O uso indiscriminado de antibióticos no tratamento de mastite caprina leva ao desenvolvimento de micro-organismos resistentes que poderão estar presentes em alimentos, colocando em risco a saúde humana. Dessa forma, a própolis surge como uma alternativa para o tratamento de doenças por possuir uma ação antimicrobiana, principalmente pela presença de flavonoides em sua composição. O objetivo desse estudo foi avaliar o potencial antimicrobiano da própolis frente à Staphylococcus spp. isolados de casos de mastite caprina e qualificar o extrato etanoico bruto por cromatografia líquida de alta eficiência (CLAE-DAD). Neste estudo, os valores de concentração bactericida mínima (CBM) dos extratos de própolis em álcool etílico, acetato de etila e hexano nos isolados foram de 6250, 3125 e 1562,5µg/mL, respectivamente. Pelo teste de aderência à microplacas, observou-se que 20,78% dos microorganismos, não foram capazes de formar biofilme, 14,70% foram classificados como moderados, 64,70% em fracos e nenhum como forte produtor de biofilme. A própolis em seus diferentes diluentes foi capaz de afetar a formação de biofilme e apresentou significativa atividade antimicrobiana frente a cepas de Staphylococcus spp., podendo ser indicada para utilização em estudos "in vivo".(AU)

Chemical composition and antimicrobial activity of two extract of propolis against isolates of Staphylococcus spp. and multiresistant bacterials / Composição química e atividade antimicrobiana de dois extratos de própolis contra isolados de Staphylococcus spp. e bactérias multirresistentes

There is a growing need to discover and develop alternative therapies for the treatment of mastitis caused by Staphylococcus spp. and multidrug-resistant bacterial infections. This study examined the chemical composition and antimicrobial potential of two propolis extracts (EPA and EPB) against seventy-seven isolates of Staphylococcus spp. obtained from subclinical bovine mastitis; three clinical strains of MRSA and two from clinical strains of S. aureus ATCC, identified as S. aureus ATCC 6538 and S. aureus ATCC 25923. The total phenolic content was determined by the Folin-Ciocalteau method, the total flavonoid content by the Dowd method and the phenolic profile was quantified by HPLC-DAD. The MBC values of the extracts were evaluated by broth microdilution method. The amount of total phenolic and flavonoid compounds was higher in EPA than EPB. Both extracts revealed the presence of caffeic, coumaric, cinnamic, ferulic and 3,4-dihydroxybenzoic acids, with higher concentrations of coumaric and cinnamic acids. Staphylococcus spp. isolates were susceptible to EPA (90.9%), EPB (83.1%) and oxacillin (80.5%). The oxacillin susceptible isolates were also susceptible to EPA (70.1%) and EPB (80.6%), whereas those oxacillin-resistant strains were also susceptible to EPA (40.0%) and to EPB (26.7%). MBC ranged from 34.3 to 68.7µm/mL for EPA and from 68.7 to 137.5µg/mL for EPB. Both extracts inhibited significantly (100%) the clinical strains of MRSA, S. aureus ATCC 6538 and S. aureus ATCC 25923 at the concentration of 68.7µg/mL. It is concluded that both extracts of propolis, whose main constituents are coumaric and cinnamic acids, have high antimicrobial activity against the microorganisms studied, and EPA also against oxacillin-resistant strains. These findings reinforce its potential use for the treatment of bovine mastitis.(AU)

É cada vez mais oportuna a necessidade de descobrir e desenvolver terapias alternativas para tratamento da mastite causada por Staphylococcus spp. e de infecções bacterianas multirresistentes. Este estudo examinou a composição química e o potencial antimicrobiano de dois extratos etanólicos de própolis (EPA e EPB) contra setenta e sete isolados de Staphylococcus spp. obtidos a partir de mastite bovina subclínica; três estirpes clínicas de MRSA e duas de linhagens clínicas de S. aureus ATCC, identificadas como, S. aureus ATCC 6538 e S. aureus ATCC 25923, ambas metacilina resistentes. O teor total de fenólicos foi determinado pelo método de Folin-Ciocalteau, o teor de flavonoides totais pelo método Dowd e o perfil fenólico foi quantificado por HPLC-DAD. CBM dos extratos foi avaliada pelo método de microdiluição em caldo. A quantidade total de compostos fenólicos e flavonoides foi maior no EPA do que no EPB. Ambos os extratos revelaram a presença dos ácidos cafeico, cumárico, cinâmico, ferúlico e 3,4-di-hidroxibenzóico, com maiores concentrações de ácidos cumárico e cinâmico. Os isolados de Staphylococcus spp. foram sensíveis a EPA (90,9%), EPB (83,1%) e oxacilina (80,5%). Os isolados suscetíveis à oxacilina também foram suscetíveis ao EPA (70,1%) e ao EPB (80,6%), enquanto os do resistente à oxacilina foram suscetíveis ao EPA (40,0%) e ao EPB (26,7%). MBC variou de 34,3 a 68,7µm/mL para EPA e de 68,7 a 137,5µg/mL para EPB. Ambos os extratos inibiram significativamente (100%) as linhagens clínicas de MRSA, S. aureus ATCC 6538 e S. aureus ATCC 25923 na concentração de 68,7µg/mL. Conclui-se que os extratos etanólicos da própolis, cujos principais constituintes são os ácidos cumário e cinâmico, possuem atividade antimicrobiana contra os micro-organismos estudados, e o EPA também contra as cepas resistentes à oxacilina. Estes achados reforçam seu potencial uso para o tratamento da mastite bovina.(AU)

Flavonoids induce cell death in Leishmania amazonensis: in vitro characterization by flow cytometry and Raman spectroscopy.

Leishmaniasis comprises a group of infectious diseases with worldwide distribution, of which both the visceral and cutaneous forms are caused by Leishmania parasites. In the absence of vaccines, efficacious chemotherapy remains the basis for leishmaniasis control. The available drugs are expensive and associated with several secondary adverse effects. Due to these limitations, the development of new antileishmanial compounds is imperative, and plants offer various perspectives in this regard. The present study evaluated the in vitro leishmanicidal activity of flavonoids isolated from Solanum paludosum Moric. and investigated the mechanisms of cell death induced by them. These compounds were evaluated in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and they showed prominent leishmanicidal activity. The EtOAc fraction, gossypetin 3,7,8,4'-tetra-O-methyl ether (1), and kaempferol 3,7-di-O-methyl ether (3) were selected to be used in an in vitro assay against L. amazonensis amastigotes and cell death assays. The flavonoids (1) and (3) presented significant activity against L. amazonensis amastigotes, exhibiting the IC50 values of 23.3 ± 4.5 µM, 34.0 ± 9.6 µM, and 10.5 ± 2.5 µM for the EtOAc fraction, (1), and (3), respectively, without toxic effects to the host cells. Moreover, (1) and (3) induced blocked cell cycle progression at the G1/S transition, ultimately leading to G1/G0 arrest. Flavonoid (3) also induced autophagy. Using Raman spectroscopy in conjunction with principal component analysis, the biochemical changes in the cellular components induced by flavonoids (1) and (3) were presented. The obtained results indicated that the mechanisms of action of (1) and (3) occurred through different routes. The results support that the flavonoids derived from S. paludosum can become lead molecules for the design of antileishmanial prototypes.

Sambucus australis Modulates Inflammatory Response via Inhibition of Nuclear Factor Kappa B (NF-kB) in vitro.

Medicinal plants have long been used as an alternative to traditional drugs for the treatment of inflammatory conditions due to the classical side effects and restricted access of various commercially available drugs, such as steroids (GCs) and nonsteroidal anti-inflammatory drugs (NSAIDs). Sambucus australis is a Brazilian herb that is commonly used to treat inflammatory diseases; however, few studies have examined the use of this species in the treatment of inflammatory conditions. The present study aims to evaluate the potential anti-inflammatory activity of S. australis in vitro. We established spleen cell cultures stimulated with pokeweed mitogen (PWM) to evaluate the production of proinflammatory cytokines, such as IL-4, IL-5, IFN-y, and IL-10 (by ELISA), and the expression of the transcription factor NF-kB (by RT-PCR). In addition, we evaluated the levels of nitric oxide in macrophage cultures and the membrane-stabilizing activity of S. australis methanolic extract (EMSA). Treatment with EMSA at concentrations of 100, 50, 25 and 12.5 µg/ml significantly decreased IL-4 (p<0.001) and IL-5 (p<0.001) levels. Treatment with 100 µg/ml EMSA reduced IFN-у (p<0.001) levels. Moreover, at 100 mg/ml, EMSA also increased IL-10 production and reduced NF-kB expression (p<0.01). In macrophage cultures stimulated with LPS, EMSA decreased nitric oxide levels (p<0.001) at all concentrations tested (100, 50, 25 and 12.5 µg/ml). Additionally, EMSA had a protective effect in the erythrocyte membrane stabilization assay. Taken together, these results suggest that S. australis has anti-inflammatory potential in vitro, characterized by the reduction of both inflammatory cytokines and the expression of NF-kB along with the up-regulation of IL-10.

New Sulphated Flavonoids and Larvicidal Activity of Helicteres velutina K. Schum (Sterculiaceae).

Helicteres velutina K. Schum (Sterculiaceae), commonly known in Brazil as 'pitó', is traditionally used by indigenous peoples as insecticides and repellents. The present work reports on the the phytoconstituents from aerial parts of H. velutina and evaluation of the larvicidal potential of its extract. The compounds were isolated using chromatographic techniques and identified by NMR, IR and LC-HRMS. This study led to the isolation of a fatty acid, one aliphatic alcohol, four chlorophyll derivatives, one steroid, triterpenes, a lignan, and flavonoids, highlighting the new compounds in the literature, 5,4'-di-hydroxy-7-methoxy-8-O-sulphate flavone (mariahine) (15a) and 5,3'-di-hydroxy-7,4'-dimethoxy-8-O-sulphate flavone (condadine) (15b). The work presented here contributes to the chemotaxonomic knowledge of the Sterculiaceae family by describing the occurrence of sulphated flavonoids in this family for the first time. The crude ethanolic extract of H. velutina featured robust larvicidal activity against Aedes aegypti larvae, showing that the extract can be useful as a domestic larvicide, just as indicated by traditional use, to combat A. aegypti, a vector insect of severe viral diseases, such as dengue and Zika.

Solanum paniculatum L. decreases levels of inflammatory cytokines by reducing NFKB, TBET and GATA3 gene expression in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Solanum paniculatum L., popularly known as jurubeba, is a common subtropical plant from Brazil, Paraguay, Bolivia and Argentina, that is used in folk medicine for the treatment of anemia, gastrointestinal disorders and inflammatory conditions in general. In addition to that, an ethnobotanical survey in "Todos os Santos" Bay have pointed out S. paniculatum as an herb to treat asthma. Previous publications have shown that S. paniculatum possesses antibiotic, antioxidant and modulatory effects on gastric acid secretion; however, its anti-inflammatory potential remains unexplored. AIM OF THE STUDY: Herein, we analyzed the S. paniculatum fruits hexane extract (SpE) for the presence of stigmasterol and ß-sitosterol and investigated the anti-inflammatory effect of SpE in vitro. MATERIALS AND METHODS: SpE was subjected to high-performance liquid chromatography (HPLC) for standardization and quantification of stigmasterol and ß-sitosterol. Spleen cells from BALB/c mice were cultivated and stimulated with pokeweed mitogen and also exposed to 15, 30 and 60µg/mL of SpE. Following treatment, levels of IFN-γ, IL-4 and IL-10 in the culture supernatants were assessed by ELISA. We also evaluated nitric oxide (NO) production by murine LPS-stimulated peritoneal macrophages using the Griess technique. In addition, the ability of SpE to stabilize membranes was assessed using a model of hemolysis induced by heat on murine erythrocytes. Gene expression of Th1-cell-specific Tbx21 transcription factor (TBET), zinc-finger transcription factor-3 (GATA3), and nuclear factor-κB (NFKB) in murine spleen cells were assessed by quantitative Polymerase Chain Reaction (qRT-PCR). RESULTS: SpE at 15, 30 and 60µg/mL significantly attenuated cell proliferation, decreased IL-4 release, reduced NO production and improved erythrocyte membrane stabilization in a concentration-dependent manner. SpE was also able to decrease the release of IFN-γ without altering IL-10 levels. The mechanism whereby SpE decreased inflammatory markers may be related to the reduction of NFKB, TBET and GATA3 gene expression. CONCLUSIONS: This study is the first to test the anti-inflammatory action of S. paniculatum. Herein, we provided evidence for the popular use of S. paniculatum in inflammatory conditions. Additional studies must be conducted to further explore the anti-inflammatory potential of SpE and to elucidate possible clinical applications.

Evaluation on the leishmanicidal activity of 2-N,N'-dialkylamino-1,4-naphthoquinone derivatives.

Parasites of the Leishmania genus are the causative agents of leishmaniasis in humans, a disease that affects more than 12 million people worldwide. In this study was evaluated in vitro leishmanicidal activity of 2-N,N'-dialkylamino-1,4-naphthoquinone derivatives, covering a series of fourteen 2-N-morpholino-, 2-N-thiomorpholino, 2-N-piperidino, 2-N-(N4-methyl)-piperazino naphthoquinones (1a-n) derived from nor-lapachol and lawsone, belong to some other di-alkyaminoderivatives. At the cytotoxicity assay on peritoneal macrophages, the compounds possessing larger alkyl groups and N-methyl-piperazino moiety (1d, 1h, 1i and 1k), showed toxic effects similar to the standard drug used pentamidine. However, the other compounds of the series showed no deleterious effect on the host cell. Meanwhile, these cytotoxic derivatives (1d, 1h and 1i) had pronounced leishmanicidal activity against L. amazonensis promastigotes, and treatments with six other compounds (1d, 1e, 1f, 1h, 1k and 1n) had significant effect leishmanicidal against L. chagasi promastigotes. In the assay against L. chagasi amastigotes, eight compounds (1a, 1b, 1c, 1d, 1h, 1i, 1k and 1m) showed significant activity. Moreover, the compounds (1a, 1b, 1c, and 1m) showed effect against amastigotes of L. chagasi and not being toxic to the host cell. These data show the derivatives as promising substances for research leishmanicidal activity.

Evaluation of the orofacial antinociceptive profile of the ethyl acetate fraction and its major constituent, rosmarinic acid, from the leaves of Hyptis pectinata on rodents

ABSTRACT Hyptis pectinata (L.) Poit., Lamiaceae, popularly known as "sambacaitá," is an aromatic shrub largely grown in the Brazilian northeastern. We investigated the antinociceptive effects of the ethyl acetate fraction obtained from the leaves of H. pectinata and of its main constituent rosmarinic acid, on formalin (2%)-, glutamate (25 µM)- and capsaicin (2.5 µg)-induced orofacial nociception in rodents. Male mice were pretreated with ethyl acetate fraction (100, 200 or 400 mg/kg, p.o.), rosmarinic acid (10 or 20 mg/kg, p.o.), morphine (5 mg/kg, i.p.), or vehicle (distilled water + 0.2% Tween 80). Ethyl acetate fraction reduced the nociceptive face-rubbing behavior during the two phase of the formalin test, whereas pretreatment with rosmarinic acid decreased the pain behavior in the second phase. Ethyl acetate fraction produced significant antinociceptive effects in the capsaicin and glutamate tests. This study showed that oral administration of ethyl acetate fraction produced potent antinociceptive effects compared to treatment with rosmarinic acid.

Toxicological, Antidiarrheal and Spasmolytic Activities of Solanum paniculatum.

Solanum paniculatum is popularly known as "jurubeba-verdadeira". In folk medicine, its roots, stems, and leaves are used as tonics, anti-inflammatories, carminatives, diuretics, and for gastrointestinal disorders. This species is listed in the Brazilian Pharmacopoeia and belongs to the "Relação Nacional de Plantas Medicinais de Interesse ao SUS". Based on folk medicine data of the Solanum genus, we decided to investigate whether the crude ethanol extract from S. paniculatum aerial parts presents toxicological, antidiarrheal, and spasmolytic activities. The crude ethanol extract from S. paniculatum aerial parts did not produce in vitro or in vivo toxicity and showed dose-dependent antidiarrheal activity, inhibiting equipotently both the defecation frequency (ED50 = 340.3 ± 35.1 mg/kg) and liquid stool formation (ED50 = 370.1 ± 19.4 mg/kg) in mice. Conversely, the crude ethanol extract from S. paniculatum aerial parts did not inhibit normal intestinal transit, even though it has shown a dose-dependent reduction of both the castor oil-induced intestinal transit (Emax = 36.9 ± 1.3 %, ED50 = 242.0 ± 8.6 mg/kg) and intestinal fluid content (Emax = 74.8 ± 2.4 %, ED50 = 328.9 ± 15.9 mg/kg). Additionally, the crude ethanol extract from S. paniculatum aerial parts was approximately 2-fold more potent in antagonizing the phasic contractions induced with histamine (IC50 = 63.7 ± 3.5 µg/mL) than carbachol 10(-6) M (IC50 = 129.3 ± 14.1 µg/mL). Therefore, we concluded that the crude ethanol extract from S. paniculatum aerial parts presents antidiarrheal activity in mice related to the inhibition of small intestinal motility and secretion as well as nonselective spasmolytic activity on the guinea pig ileum.

New Alcamide and Anti-oxidant Activity of Pilosocereus gounellei A. Weber ex K. Schum. Bly. ex Rowl. (Cactaceae).

The Cactaceae family is composed by 124 genera and about 1438 species. Pilosocereus gounellei, popularly known in Brazil as xique-xique, is used in folk medicine to treat prostate inflammation, gastrointestinal and urinary diseases. The pioneering phytochemical study of P. gounellei was performed using column chromatography and HPLC, resulting in the isolation of 10 substances: pinostrobin (1), ß-sitosterol (2), a mixture of sitosterol 3-O-ß-d-glucopyranoside/stigmasterol 3-O-ß-d-glucopyranoside (3a/3b), 13²-hydroxyphaeophytin a (4), phaeophytin a (5), a mixture of ß-sitosterol and stigmasterol (6a/6b), kaempferol (7), quercetin (8), 7'-ethoxy-trans-feruloyltyramine (mariannein, 9) and trans-feruloyl tyramine (10). Compound 9 is reported for the first time in the literature. The structural characterization of the compounds was performed by analyses of 1-D and 2-D NMR data. In addition, a phenolic and flavonol total content assay was carried out, and the anti-oxidant potential of P. gounellei was demonstrated.

Evaluation of naphthoquinones identified the acetylated isolapachol as a potent and selective antiplasmodium agent.

This study reports on the design, synthesis and antiparasitic activity of three new semi-synthetic naphthoquinones structurally related to the naturally-occurring lapachol and lapachone. Of the compounds tested, 3-(3-methylbut-1-en-1-yl)-1,4-dioxo-1,4-dihydronaphthalen-2-yl acetate (1) was the most active against Plasmodium falciparum among both natural and semi-synthetic naphthoquinones, showing potent and selective activity. Compound 1 was able to reduce the in vitro parasite burden, in vitro parasite cell cycle, as well as the blood parasitemia in Plasmodium berghei-infected mice. More importantly, infection reduction under compound 1-treatment was achieved without exhibiting mouse genotoxicity. Regarding the molecular mechanism of action, this compound inhibited the hemozoin crystal formation in P. falciparum treated cells, and this was further confirmed by observing that it inhibits the ß-hematin polymerization process similarly to chloroquine. Interestingly, this compound did not affect either mitochondria structure or cause DNA fragmentation in parasite treated cells. In conclusion, we identified a semi-synthetic antimalarial naphthoquinone closely related to isolapachol, which had stronger antimalarial activity than lapachol.

Antioxidant and antimicrobial properties of ethanolic extract of Libidibia ferrea pods / Propriedade antioxidante e antimicrobiana do extrato etanólico de vagens de Libidibia ferrea

Libidibia ferrea is a typical plant of northern and north-east Brazil and has well-known medicinal properties that can be found in ethanolic extracts such as antipyretic, anti-inflammatory and anti-rheumatic compounds. This study seeks to evaluate the potential antioxidant and antimicrobial activity of ethanol extracts from Libidibia ferrea pods. The pods were used for the preparation of ethanolic extracts of L. ferrea which is used to determine biological activity, and measure their total phenolic content. For quantification of antioxidant methods of DPPH, ABTS and ß-carotene were employed and the method of minimum inhibitory concentration (MIC) to measure the antimicrobial activity. The ethanolic extract of L. ferrea showed excellent antioxidant activity, as well as other similar substances commonly used for this purpose such as citric acid and trolox. In addition, it had antimicrobial activity against Gram-negative and Gram-positive bacteria.(AU)

Libidibia ferrea é uma planta típica do norte e nordeste do Brasil conhecida por suas propriedades medicinais que podem ser encontrados em extratos alcoólicos, possui compostos antipiréticos, anti-inflamatórios e antirreumáticos. Este estudo visa avaliar o potencial antioxidante e atividade antimicrobiana do extrato etanólico de vagens de Libidibia ferrea. As vagens foram empregadas na preparação de extrato etanólico de L. férrea, utilizado na determinação da atividade biológica, e para mensurar seu conteúdo fenólico total. Os métodos DPPH, ABTS e ß-caroteno foram utilizados para quantificar a atividade antioxidante, e o método da Concentração Inibitória Mínima (CIM) para avaliar a atividade antimicrobiana. O extrato etanólico de L. ferrea apresentou atividade antioxidante excelente, bem como outras substâncias compatíveis normalmente utilizadas para este fim, tais como ácido cítrico e trolox. Além disso, demonstrou atividade antimicrobiana contra bactérias Gram-negativas e Gram-positivas.(AU)

Distribution of metabolites in galled and non-galled leaves of Clusia lanceolata and its antioxidant activity

Essential oils of galled and non-galled leaves of Clusia lanceolata Cambess., Clusiaceae, were obtained by hydrodistillation and analyzed by GC and GC/MS. The chemical composition of both oils was similar, with a predominance of sesquiterpene caryophyllenes. The extracts from the leaves were evaluated regarding total phenols, flavonoids and proanthocyanidins. Galled leaves showed higher levels of phenolics and proanthocyanidins, since the content of flavonoids was higher in non-galled leaves. The chromatographic profiles of extracts were obtained by using HPLC/DAD and LC-ESI-MS. Electrospray ionisation (ESI) in positive and negative ion mode was used to identify four flavones C-glycosides in both extracts. The study constitutes a first report on the chemical research of C. lanceolata. The extract from galled leaves had a higher antioxidant activity.

Synthesis, leishmanicidal activity and theoretical evaluations of a series of substituted bis-2-hydroxy-1,4-naphthoquinones.

A series of eight substituted bis-2-hydroxy-1,4-naphthoquinone derivatives was synthesized through lawsone condensation with various aromatic and aliphatic aldehydes under mild acidic conditions. The title compounds were evaluated for antileishmanial activity in vitro against Leishmania amazonensis and Leishmania braziliensis promastigotes; six compounds showed good activity without significant toxic effects. The compound with the highest activity was used for an in vivo assay with Leishmania amazonensis.