Evaluation of antitumoral and antioxidant activities of the hydroalcoholic extract and fractions obtained from the fruit pericarp of Sapindus saponaria L.

The fruits of Sapindus saponaria L., popularly known as 'saboeiro', have been used in medicine. This study evaluated the antioxidant and antitumor activities of the hydroethanolic extract (HAE) and fractions obtained from the fruit pericarp of S. saponaria. The HAE was obtained from the S. saponaria fruit pericarp by maceration; this was followed by fractionation using reversed-phase solid-phase extraction, resulting in fractions enriched with acyclic sesquiterpenic oligoglycosides (ASOG) and saponins (SAP1, and SAP2), confirmed by mass spectrometry with electrospray ionization (ESI-QTOF-MS). The greatest citotoxic activity was observed with the SAP1 fraction against the CaCo2 cell line with a GI50 of 8.1 µg mL-1, while the SAP2 fraction had a GI50 of 13.6 µg mL-1 against CaCo2. The HAE demonstrated the greatest antioxidant activity. S. saponaria has potential therapeutic use in the pharmaceutical industry as a natural anti-oxidant or antitumor product.

In vitro and in vivo antileishmania activity of sesquiterpene lactone-rich dichloromethane fraction obtained from Tanacetum parthenium (L.) Schultz-Bip.

The discovery of new treatments for neglected diseases, including leishmaniasis, is a substantial challenge for scientific research. Plant extracts have shown potential in the selective treatment of tropical diseases. The present study evaluated the in vitro and in vivo antileishmania effects of a sesquiterpene lactone-rich dichloromethane fraction (DF) obtained from the aerial parts of Tanacetum parthenium (L.) Schultz-Bip. In vitro studies of the DF indicated an IC50 of 2.40±0.76 µg mL(-1) against the promastigote form and 1.76±0.25 µg mL(-1) against the axenic amastigote form of Leishmania amazonensis. In vivo intramuscular treatment with DF decreased the growth and size of footpad lesions in mice. The DF also significantly decreased the parasite population compared with animals that were treated with the reference drug. Plasma malondialdehyde levels were increased slightly by the DF, attributable to its parthenolide-rich composition that causes cellular apoptosis, compared with the control group, demonstrating treatment efficacy without toxicity or genotoxicity. Because the isolation and purification of plant compounds are costly and time-consuming and generate low yields, extract fractions, such as the DF studied herein, represent a promising alternative for the treatment of leishmaniasis.

Alkaloids and triterpene from Almeidea coerulea (Nees and Mart.) a. St.-Hil. and anti-leishmanial activity

The dichloromethane extract of Almeidea coerulea stems yielded the (11-hydroxyrutaecarpine alkaloid reported for the first time from this species) and the triterpene (28-hydroxy-28, 29-dihydrolupeol). The dictamine, skimianine, sitosterol and stigmasterol were also isolated from methanol extract. Extracellular forms of Leishmania amazonensis (promastigotes) was tested with dichloromethane extract and 28-hydroxy-28, 29-dihydrolupeol with showed anti-leishmanial activity above 0.1 mg/mL and 75µg/mL (inhibited 50 percent promastigote growth), respectively.

In vitro activity of the essential oil of Cymbopogon citratus and its major component (citral) on Leishmania amazonensis.

Leishmaniasis causes considerable mortality throughout the world, affecting more than 12 million people. Cymbopogon citratus (DC) Stapf, Family Poaceae, is a widely used herb in tropical countries and is also known as a source of ethnomedicines. In this study, the inhibitory effect and the morphological and ultrastructural alterations on Leishmania amazonensis by the essential oil (EO) of C. citratus and its main constituent, citral, were evaluated. The results showed that the antiproliferative activity of EO on promastigotes and axenic amastigotes, and intracellular amastigote forms of L. amazonensis was significantly better than citral, and indicated a dose-dependent effect. Neither compound showed a cytotoxic effect on macrophage strain J774G8. The promastigote forms of L. amazonensis underwent remarkable morphological and ultrastructural alterations compared with untreated cultures. These alterations were visible by light, scanning, and transmission electron microscopy of promastigotes treated with EO and citral at concentrations corresponding to the IC(50) (1.7 and 8.0 microg/ml) and IC(90) (3.2 and 25 microg/ml), respectively, after 72 h of incubation. This study revealed that citral-rich essential oil from C. citratus has promising antileishmanial properties, and is a good candidate for further research to develop a new anti-protozoan drug.

Anti-leishmanial activity of alkaloidal extract from Aspidosperma ramiflorum

Infections due to protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials (SbV), which present renal and cardiac toxicity. Besides, the precise chemical structure and mechanism of action of these drugs are unknown up to date. In order to find new drugs against leishmaniasis, we have been studying extracts of Brazilian trees. In the present study, we have evaluated the effectiveness of an alkaloid extract of Aspidosperma ramiflorum Muell. Arg. (Apocynaceae), against the extracellular forms promastigotes of L. (L.) amazonensis and L. (V.) braziliensis. The alkaloid extract of A. ramiflorum was much more effective against L. (L.) amazonensis (LD50 < 47 µg/ml) than L. (V.) braziliensis. Based on these in vitro results against L. (L.) amazonensis new studies should be made to find the compounds with anti-leishmanial activity.