ABSTRACT Pentavalent antimonials and amphotericin B remain as the main drugs to treat human leishmaniasis. However, the high toxicity and variable efficacy of treatment have stimulated the search for novel drug candidates. Naturally occurring alkaloids have a long history of antileishmanial activity. Here, we investigate the effects of the β-carboline-1-propionic acid alkaloid isolated from Quassia amara L., Simaroubaceae, against Leishmania amazonensis and Leishmania infatum. The alkaloid was isolated after liquid-liquid fractionation followed by chromatographic purification of the Q. amara methanol extract. The antileishmanial activity was evaluated by the microdilution method, using resazurin as the viability indicator. In addition, annexin and propidium iodide were used to detect parasites undergoing apoptosis. The anti-amastigote activity of the β-carboline-1-propionic acid alkaloid was determined by the infection of RAW 264.7 macrophages. The alkaloid displayed leishmanicidal activity against Leishmania amazonensis and L. infantum promastigotes and intracellular amastigotes with 50% inhibitory concentration ranging from 2.7 ± 0.82 to 9.4 ± 0.5 µg/ml and selectivity indexes >10. Moreover, apoptotic Leishmania amazonensis (19.5%) and L. infantum (40.4%) promastigotes were detected after 5 h incubation with the alkaloid. Finally, the β-carboline-1-propionic acid alkaloid inhibited the production of NO of infected macrophages, suggesting that the intracellular amastigote elimination occurs in a nitrosative stress-independent way. The results shown here suggest that the β-carboline-1-propionic acid alkaloid has potential as an antileishmanial agent.

ABSTRACT Stingless bee products such as honey, pollen, propolis, and geopropolis have been used for centuries in traditional medicine for the treatment of several illnesses. Investigation of the biological activity of stingless bee products, especially propolis and geopropolis, has revealed promising therapeutic properties. About 20% of total Neotropical stingless bees can be found in Brazil. Despite the species diversity, studies on their biological activity are scarce. The present review focuses on the antioxidant and antimicrobial activities of propolis and geopropolis from Brazilian stingless bees. In addition, the toxicity of these natural products was addressed. In order to provide new evidences for the toxic potential of propolis and geopropolis components, an in silico analysis was performed using the ADMET PredictorTM software. We observed that most of studies evaluated only crude ethanol extracts of a limited number of stingless bees species. Propolis and geopropolis displayed antioxidant capacity and antimicrobial activity. Concerning the toxic potential, the extracts of stingless bees propolis and geopropolis were considered safe. Nonetheless, in vitro and in vivo toxicological studies are still necessary.

Abstract This study aimed to prepare hydrogel containing Cymbopogon citratus (DC.) Stapf, Poaceae, volatile oil encapsulated in poly (d,l-lactide-co-glycolide) nanoparticles and to evaluate its in vitro anti-herpetic activity. Polymeric nanoparticles were prepared by solvent emulsification-diffusion method and incorporated in carbomer hydrogels. In vitro release profiles for the nanogel, loaded nanoparticles and hydrogel containing free oil were evaluated by dialysis. Inhibitory activities against Herpes simplex for the formulations were investigated in Vero cells. Hydrogel was developed using nanoparticles with mean diameter of 217.1 nm and negative Zeta potential (−20.5 mV). Volatile oil release profile showed a biphasic pattern with an initial faster release and subsequent sustained phase in all formulations. Nanogel strongly inhibited virus in a non-cytotoxic concentration, 42.16 times lower than free oil, 8.76 and 2.23 times than loaded nanoparticles and hydrogel containing free oil, respectively. These results highlight the potential of nanogel to protect oil against volatilization, control release and improve its anti-herpetic activity.

<p>This paper describes the correlation between the phenolic composition and the molecular phylogenetic reconstruction of five <italic>Spondias</italic> species (Anacardiaceae). Two of these species (<italic>S. venulosa</italic> and <italic>Spondias</italic> sp.) occur in rainforest areas and the other three are widely distributed in Brazil (<italic>S. dulcis</italic>, <italic>S.mombin</italic>, and <italic>S. purpurea</italic>). The flavonoid enriched fraction of the <italic>S. venulosa</italic> leaf extract also underwent a chemical study. The results indicate that the presence of flavonol 3-<italic>O</italic>-glycosides are a synapomorphic character of the studied American <italic>Spondias</italic> and the production of rhamnetin 3-<italic>O</italic>-rutinoside is a synapomorphy of the Atlantic forest species. This is the first report of flavonoids in <italic>S. venulosa</italic>, an endemic species from the Brazilian Atlantic rainforest.</p>

The monoterpenoid 1,8-cineole is obtained from the leaves of Eucalyptus globulus and it has important biological activities. It is a cheap natural substrate because it is a by-product of the Eucalyptuscultivation for wood and pulp production. In this study, it was evaluated the potential of three filamentous fungi in the biotransformation of 1,8-cineole. The study was divided in two steps: first, reactions were carried out with 1,8-cineole at 1 g/L for 24 h; afterwards, reactions were carried out with substrate at 5 g/L for 5 days. The substrate was hydroxylated into 2-exo-hydroxy-1,8-cineole and 3-exo-hydroxy-1,8-cineole by fungi Mucor ramannianus and Aspergillus niger with high stereoselectivity. Trichoderma harzianum was also tested but no transformation was detected. M. ramannianus led to higher than 99% of conversion within 24 h with a starting high substrate concentration (1 g/L). When substrate was added at 5 g/L, only M. ramannianuswas able to catalyze the reaction, but the conversion level was 21.7% after 5 days. Both products have defined stereochemistry and could be used as chiral synthons. Furthermore, biological activity has been described for 3-exo-hydroxy-1,8-cineol. To the best of our knowledge, this is the first report on the use of M. ramannianus in this reaction.

The isolation of bioactive compounds from medicinal plants, based on traditional use or ethnomedical data, is a highly promising potential approach for identifying new and effective antimalarial drug candidates. The purpose of this review was to create a compilation of the phytochemical studies on medicinal plants used to treat malaria in traditional medicine from the Community of Portuguese-Speaking Countries (CPSC): Angola, Brazil, Cape Verde, Guinea-Bissau, Mozambique and São Tomé and Príncipe. In addition, this review aimed to show that there are several medicinal plants popularly used in these countries for which few scientific studies are available. The primary approach compared the antimalarial activity of native species used in each country with its extracts, fractions and isolated substances. In this context, data shown here could be a tool to help researchers from these regions establish a scientific and technical network on the subject for the CPSC where malaria is a public health problem.

Este trabalho compara pela primeira vez a composição química do óleo essencial das folhas de Licaria canella coletadas em duas estações climáticas. Os resultados foram comparados com os obtidos para o óleo essencial das folhas de outra espécie da família Lauraceae, Aniba canelilla, coletada no mesmo período. Ambos os óleos essenciais foram analisados por CG-DIC e CG-EM, e os resultados indicaram uma grande quantidade de benzenóides, sendo o principal constituinte em L. canella o benzoato de benzila e para A. canelilla, o 1-nitro-2-feniletano. A comparação das atividades biológicas mostrou que o óleo de L. canella (IC50 19 µg mL-1) foi mais ativo contra as cepas de Leishmania amazonensis e menos citotóxico em cultura de macrófagos do que o de A. canelilla (IC50 40 µg mL-1). Por outro lado, o óleo de L. canella exibiu uma maior citotoxicidade contra Artemia salina com uma concentração letal (CL50) igual a 5,25 µg mL-1.

This work compares the chemical composition of the essential oils from the leaves of Licaria canella collected in two different seasons. The results of this investigation were compared with the leaf essential oils of other species of the Lauraceae family, Aniba canelilla, collected at the same time. Both essential oils were analyzed by GC-FID and GC-MS. The results demonstrated a larger predominance of benzenoids, being the main constituent benzyl benzoate for L. canella and 1-nitro-2-phenylethane for A. canelilla. The comparison of the biological activities showed that L. canella (IC50 19 µg mL-1) was more active against Leishmania amazonensis strains and less cytotoxic in macrophage cultures than A. canelilla (IC50 40 µg mL-1). On the other hand, the L. canella oil displayed a higher cytotoxicity against Artemia salina with a lethal concentration (LC50), equal to 5.25 µg mL-1.

O polímero do látex de Himatanthus sucuuba (Spruce) Woodson foi identificado por métodos espectroscópicos como o cis-poliisopreno (Mn = 192; Mw = 571; Mw /Mn= 2.97). A análise de microelementos na fase aquosa por ICP-MS forneceu Ca (354 mg/g) e Mg (259 mg/g) como elementos majoritários. A detecção de carboidratos na fase aquosa por CLAE-DPA apresentou arabinose, glucose, xilose, ramnose e galactose como açúcares principais.

The polymeric material in the latex of Himatanthus sucuuba (Spruce) Woodson was identified by spectroscopic methods as cis-polyisoprene (Mn = 192; Mw = 571; Mw/ Mn = 2.97). ICP-MS analysis of microelements in the aqueous phase showed the most abundant to be Ca (354 μg/g) and Mg (250 μg/g). Carbohydrate analysis of the aqueous phase by HPLC-PAD showed arabinose, glucose, xylose, rhamnose and galactose to be the predominant saccharides.

O fracionamento do extrato acetato de etila de frutos de Punica granatum, guiado por ensaios antimicrobianos frente a colônias de Staphylococcus aureus resistentes à meticilina, conduziu ao isolamento e à determinação estrutural do tanino elágico punicalagina. A identificação da substância foi realizada por CLAE/UV e RMN de ¹H. Os ensaios antimicrobianos foram realizados pelo método de difusão em discos de papel. A concentração mínima inibitória das substâncias foi determinada pelo método de diluição em agar padronizada pelo NCCLS (National Committee for Clinical Laboratory Standards).

The ethyl acetate extract of Punica granatum fruits was fractionated by chromatographic techniques to afford the ellagitannin punicalagin. The substance was found to be active against methicillin-resistant Staphylococcus aureus strains and was identified by HPLC/UV and ¹HNMR. The antibacterial assays which guided the isolation of the tannin were conducted using the disc diffusion method. Minimum inhibitory concentration (MIC) was determined by the dilution method according to NCCLS (National Committee for Clinical Laboratory Standards) procedure.