Antinociceptive effect of Nephelium lappaceum L. fruit peel and the participation of nitric oxide, opioid receptors, and ATP-sensitive potassium channels

Introduction:Nephelium lappaceum L. (Sapindaceae) is a plant known as rambutan. It is used for various purposes in traditional medicine.Objective: We aimed to evaluate the antinociceptive effects of the ethanol extract of the fruit peel of N. lappaceum (EENL), the mechanisms involved in these effects, and the acute toxicity in zebrafish.Methods: We performed chromatography coupled to mass spectrometry, acute toxicity assay in zebrafish, and evaluation in mice submitted to models of nociception and locomotor activity.Results: We identified (epi)-catechin, procyanidin B, and ellagic acid and its derivatives in EENL. We did not find any toxicity in zebrafish embryos incubated with EENL. The locomotor activity of mice submitted to oral pretreatment with EENL was not changed, but it reduced the abdominal constrictions induced by acetic acid, the licking/biting time in both the first and second phase of formalin testing and capsaicin testing, and carrageenan-induced paw mechanical allodynia. Oral pretreatment with EENL increased latency time in the hot plate test. This antinociceptive effect was significantly reversed by naloxone, L-arginine, and glibenclamide respectively showing the participation of opioid receptors, nitric oxide, and KATP channels as mediators of EENL-induced antinociception.Conclusion: EENL causes antinociception with the participation of opioid receptors, nitric oxide, and KATP channels, and is not toxic to zebrafish

Aspidosperma pyrifolium, a medicinal plant from the Brazilian caatinga, displays a high antiplasmodial activity and low cytotoxicity

Abstract Background Several species of Aspidosperma plants are referred to as remedies for the treatment of malaria, especially Aspidosperma nitidum. Aspidosperma pyrifolium, also a medicinal plant, is used as a natural anti-inflammatory. Its fractionated extracts were assayed in vitro for activity against malaria parasites and for cytotoxicity. Methods Aspidosperma pyrifolium activity was evaluated against Plasmodium falciparum using extracts in vitro. Toxicity towards human hepatoma cells, monkey kidney cells or human monocytes freshly isolated from peripheral blood was also assessed. Anti-malarial activity of selected extracts and fractions that presented in vitro activity were tested in mice with a Plasmodium berghei blood-induced infection. Results The crude stem bark extract and the alkaloid-rich and ethyl acetate fractions from stem extract showed in vitro activity. None of the crude extracts or fractions was cytotoxic to normal monkey kidney and to a human hepatoma cell lines, or human peripheral blood mononuclear cells; the MDL50 values of all the crude bark extracts and fractions were similar or better when tested on normal cells, with the exception of organic and alkaloidic-rich fractions from stem extract. Two extracts and two fractions tested in vivo caused a significant reduction of P. berghei parasitaemia in experimentally infected mice. Conclusion Considering the high therapeutic index of the alkaloidic-rich fraction from stem extract of A. pyrifolium, it makes the species a candidate for further investigation aiming to produce a new anti-malarial, especially considering that the active extract has no toxicity, i.e., no mutagenic effects in the genototoxicity assays, and that it has an in vivo anti-malarial effect. In its UPLC-HRMS analysis this fraction was shown to have two major components compatible with the bisindole alkaloid Leucoridine B, and a novel compound, which is likely to be responsible for the activity against malaria parasites demonstrated in in vitro tests

Unprecedented one-pot sequence for the synthesis of tetrahydroquinoline alkaloids and preliminary evaluation of their antibacterial activity

O link não abre! Favor corrigir.A novel one-pot sequence (in 2 or 3 steps) was developed for the synthesis of the tetrahydroquinoline alkaloids (±)-galipinine, (±)-cuspareine, (±)-galipeine and (±)-angustureine, and the derivative (±)-11-methoxy-5,6,6a,7,8,13-hexahydro-13a-aza-benzo[5,6]cyclohepta [1,2-a]naphthalene-12-ol from their respective Wittig adducts in moderate and high yields. The solvolytic N-methylation reaction was shown to be catalyzed by Pt0, generated in situ by reduction of PtO2. The evaluation of biofilm inhibition and antibacterial activity of the compounds against Staphylococcus aureus strains isolated from cows with mastitis revealed that the alkaloid derivative is a promising candidate for an antibiotic drug

Antifungal activity of extracts from Atacama Desert fungi against Paracoccidioides brasiliensis and identification of Aspergillus felis as a promising source of natural bioactive compounds

Submitted by Nuzia Santos ([email protected]) on 2016-08-22T13:59:12Z No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2016-08-22T14:05:49Z (GMT) No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5)Made available in DSpace on 2016-08-22T14:05:49Z (GMT). No. of bitstreams: 1 ve_Mendes_Graziele_ Antifungal_CPqRR_2016.pdf: 614207 bytes, checksum: 63480c12960be7ef23f94df4e4a6d7da (MD5) Previous issue date: 2016Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Departamento de Fisiologia e Biofísica. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratório de Química de Produtos Naturais. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Microbiologia. Belo Horizonte, MG, BrasilFungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity

Flavonol triglycosides of leaves from Maytenus robusta with acetylcholinesterase inhibition.

Although Maytenus robusta aqueous infusions of leaves are used in Brazilian traditional medicine for stomach disease treatment, only a few chemical studies of this species are found in literature. The phytochemical investigation of methanol extract from M. robusta leaves yielded the known compound kaempferol (3) and two new flavonol glycosides: kaempferol-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (1) and quercetin-3-O-b-D-glucopyranosyl-(1 !3)-a-Lrhamnopyranosyl-( 1 ! 2)-b-D-glucopyranoside (2). The chemical structures of 1 and 2 were elucidated by 1D/2D NMR, ESI?MS and ESI?MS2 spectral data. It is the first time flavonoids have been reported from M. robusta. Flavonols 1 and 2 showed 66% and 80% acetylcholinesterase (AChE) inhibition, compared to 93% of the standard eserine, by the Ellman?s method. These substances are one of the few active flavonols linked to a trisaccharide chain in the literature presenting this activity, and contribute to the screening for new types of natural AChE inhibitors