The leishmaniases are severe parasitic diseases that occur worldwide, caused by protozoa of the genus Leishmania. Studies with medicinal plants can lead to a range of possibilities for treating and improving the patients' quality of life. Research on Azadirachta indica fractions and extracts has shown that they have excellent anti-leishmanial activity based on bioactivity-guided fractionation of ethanolic extracts of leaves and seeds and in vitro activity against promastigotes. In this research the most effi cient extracts and fractions were selected for tests on intracellular amastigotes of Leishmania amazonensis. The ethanolic extract of the leaves and dichloromethane and chloroform fractions had IC 50 values of 38, 3.9 and 1.2 μg/mL for promastigotes and 9.8, 1.1 and 0.6 μg/mL for amastigotes, respectively, at 72 hours. For the ethanolic extract and dichloromethane fraction from nut tegument, the IC 50 was 2.7 and 2.1 μg/mL for promastigotes and 0.4 and 0.6 μg/mL for amastigotes. The cytotoxicity of the fractions presented selectivity that was between 8 to 32 times more toxic to promastigotes and 15 to 72 times to amastigotes than to macrophages. The extracts and fractions from leaves and fruits were more eff ective against amastigotes, and the fractionation increased activity against both promastigotes and amastigotes, enabling us to obtain potentially active fractions with low toxicity.

The brine shrimp (Artemia salina Leach) lethality bioassay offers an advantage in standardization and quality control of botanical products. This test is well correlated with antitumor activity (cytotoxicity) and can be used to monitor the activity of bioactive natural products. This paper reports the bioactivity of ethanol extracts from seven medicinal plants from the Northeast of Brazil (Acmella uliginosa, Ageratum conyzoides, Eugenia uniflora, Plectranthus neochilus, Moringa oleifera, Justicia pectoralis and Equisetum sp.) against Artemia salina. Biological activity was evaluated for extracts at 1, 10, 100, and 1000 µg/mL in triplicate, and the mean lethal concentration values (LC 50 ) were obtained by probit analysis. The species Acmella uliginosa showed the highest bioactivity, and its flower extract was more active than its leaf extract. Keywords

Propolis is a complex matrix of chemical constituents extracted from plants and produced by bees which is used in folk medicine due to its several pharmacological properties. Its chemical composition varies according to the region where it is produced. This work has studied the antileishmanial activity and cytotoxicity of brown propolis (BP) originating from the semi-arid region of Piauí, Brazil. The BP showed significant inhibition of the Leishmania amazonensis promastigotes growth as well as being effective in reducing infection of murine macrophages and the number of internalised amastigotes in these cells. The dichloromethane fraction was the most active and showed the best selectivity index. The studied samples presented good activity and the fractioning improved the antileishmanial activity without an increase in the cytotoxicity against mammalian cells. Therefore, BP is a potential source for development of apitherapeutic products for the treatment of leishmaniasis.

Garcinielliptone FC (GFC), a natural prenylated benzophenone, was extracted from Platonia insignis Mart. (Clusiaceae), a native plant commonly known as bacuri and used in traditional Brazilian medicine for the treatment of skin diseases. The aim of this study was to evaluate the cytotoxic and leishmanicidal effects of GFC using in vitro models. The experimental data demonstrated that the polyisoprenylated benzophenone GFC possesses cytotoxic and leishmanicidal activities.

The present study primarily aims to identify the relative density and the fatty acids (methyl esters) content present in the standardized ethanol extract of leaves of M. glomerata (EPMG). Meanwhile, in a second moment, this study evaluated the effects of the EPMG on the levels of amino acids in the hippocampus, and the mechanism of sedative and anxiolytic action. Adult mice were treated with doses of 200, 300, and 400 mg/kg and evaluated in open field, elevated plus-maze, light dark, and rotarod tests. Moreover, in the behavioral tests diazepam (GABAergic anxiolytic, 2 mg/kg) as positive control and flumazenil (GABA antagonist, 2.5 mg/kg) were used to identify mechanism of sedative and anxiolytic action produced by EPMG. The EPMG is constituted by the following compounds: methyl cinnamate, 2H-1-benzopyran-2-one, (2-hydroxyphenyl)methyl propionate, (Z)-methyl-hexadec-7-enoate, methyl hexadecanoate, hexadecanoic acid, (Z)-methyl-octadec-9-enoate, octadecanoic acid, and squalene. This extract demonstrated anxiolytic effects, which may be mediated by GABAergic system, and was able to increase GABA levels and reduce of glutamate and aspartate concentrations in mice hippocampus, which can directly and/or indirectly assist in their anxiolytic effect. Although more studies are needed, the EPMG could represent an interesting therapeutical strategy in the treatment of anxiety.