Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon.

INTRODUCTION: Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated from M. guianensis. METHODS: Maytenus guianensis stems and leaves were extracted in acetone, followed by the preparation of eluates and isolation of secondary metabolites using chromatography on a glass column with silica gel as the fixed phase. The chemical components were identified using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance of hydrogen-1 and carbon-13, mass spectroscopy, and infrared spectroscopy. The anti-Leishmania amazonensis activities of these eluates and compounds were evaluated by direct promastigote counting and viability assays. RESULTS: It was found that the hexane bark eluate produced the strongest anti-L. amazonensis effect, with 90-100% inhibition of the promastigote form. The isolated metabolite that produced the best result was tingenone B, followed by a compound formed by the union of tingenone and tingenone B (80-90% inhibition). CONCLUSIONS: Maytenus guianensis shows anti-parasite activity that warrants further investigation to determine the mechanisms underlying this antileishmanial effect and to evaluate the pharmacological potential of these eluates and isolated secondary metabolites, while minimizing any adverse effects.

Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon

Abstract INTRODUCTION Maytenus guianensis is a member of the Celastraceae family that is used in traditional medicine, particularly for its anti-parasitic and anti-cancer effects. To explore the ethnopharmacological potential of this plant, the present study was designed to screen the in vitro antileishmanial activities of extracts and compounds isolated from M. guianensis. METHODS Maytenus guianensis stems and leaves were extracted in acetone, followed by the preparation of eluates and isolation of secondary metabolites using chromatography on a glass column with silica gel as the fixed phase. The chemical components were identified using spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance of hydrogen-1 and carbon-13, mass spectroscopy, and infrared spectroscopy. The anti-Leishmania amazonensis activities of these eluates and compounds were evaluated by direct promastigote counting and viability assays. RESULTS It was found that the hexane bark eluate produced the strongest anti-L. amazonensis effect, with 90-100% inhibition of the promastigote form. The isolated metabolite that produced the best result was tingenone B, followed by a compound formed by the union of tingenone and tingenone B (80-90% inhibition). CONCLUSIONS Maytenus guianensis shows anti-parasite activity that warrants further investigation to determine the mechanisms underlying this antileishmanial effect and to evaluate the pharmacological potential of these eluates and isolated secondary metabolites, while minimizing any adverse effects.

Acute genotoxicity analysis in vivo of the aqueous extract of Maytenus guyanensis Amazonian chichuá

Abstract The species Maytenus guyanensis Klotzsch ex Reissek, Celastraceae, present a wide variety of possible pharmacological activities and its roots and stems are used by popular medicine in the western Amazon rainforest. Few studies have demonstrated the genotoxic safety of the popular use of this species, and owing to this, the present study aimed to perform an analysis of the acute genotoxicity in vivo of the aqueous extract of M. guyanensis. Male and female mice from Mus musculus species, of weights ranging from 20 to 40 g, organized in eight groups with different treatments were used. The aqueous extracts of the bark of M. guyanensis were administered orally by gavage with 0.1 ml of the test substance per 10 g of the animal, followed by performance of comet assay in peripheral blood, PCE/NCE correlation and occurrence of micronuclei in the bone marrow. It was found that the aqueous extract of M. guyanensis, with ten times higher concentration than those used in ethnopharmacology, did not present genotoxic effect and, moreover, it has antigenotoxic action in mice treated acutely. Further studies regarding bioaccumulation and chronic effects of this species are suggested, in order to improve the understanding of its mechanism of action, ensuring the efficacy and safety of its utilization and developing phytotherapics and drugs.

Plantas da Amazônia brasileira com potencial leishmanicida in vitro / Plants of the Brazilian Amazon with potential in vitro antileishmania activity

A preocupação em buscar novos fármacos para o tratamento da leishmaniose é cada vez maior em virtude da toxicidade dos existentes e do aumento da resistência do parasito, o que representa uma ameaça ao controle da doença. O presente estudo apresenta uma revisão bibliográfica sobre as plantas da Amazônia brasileira com potencial atividade leishmanicida in vitro. Constatouse uma grande diversidade de espécies vegetais da Amazônia brasileira com potencial para a investigação de novos fitoterápicos e metabólitos secundários com ação leishmanicida, além do tratamento de outras parasitoses negligenciadas. A presente revisão demonstrou que as espécies dos gêneros Casearia, Croton e Physalis são fortes candidatas para busca de novos fármacos, visto que apresentaram um IC50 menor que 1µg/mL em testes in vitro contra as formas promastigotas ou amastigotas de Leishmania spp. Ressalta-se a importância de estudos futuros sobre espécies que apresentem metabólitos terpenoides ou esteroides em virtude do potencial leishmanicida que têm demonstrado.

Antimalarial ethnopharmacology in the Brazilian Amazon / Etnofarmacologia antimalárica na Amazônia Brasileira

The preoccupation to find new drugs for the treatment of malaria is increasing steadily due to the resistance of the parasite, which is a threat to disease control, The present study describes a literature review on the antimalarial ethnopharmacology (Anti-Plasmodium falciparum - in vitro) of the Brazilian Amazon plants, It was found a great diversity of plant species in the Brazilian Amazon with potential for research of new herbal and secondary metabolites with antiplasmodial action, in addition to treating other neglected parasitic diseases, However, for these studies is needed in addition to financial support, the interaction between different laboratories and research groups for the formation of multidisciplinary and interdisciplinary teams, which will enhance the research level in the region and increase the likelihood of new antimalarial drugs discovery...

Está cada vez maior a necessidade em se buscar novos fármacos para o tratamento da malária, principalmente devido à resistência do parasito, o que é uma ameaça ao controle da doença. O presente estudo descreve uma revisão bibliográfica sobre a etnofarmacologia antimalárica (Anti-Plasmodium falciparum - in vitro) de plantas da Amazônia brasileira. Constatou-se uma grande diversidade de espécies vegetais na Amazônia brasileira com potencial para a investigação de novos fitoterápicos e metabólitos secundários com ação antiplasmodial, além do tratamento de outras parasitoses negligenciadas. Porém, para a realização desses estudos são necessários além de apoio financeiro, a interação entre diferentes laboratórios e grupos de pesquisa para a formação de equipes multidisciplinares e interdisciplinares, o que irá potencializar o nível da pesquisa na região e aumentar a probabilidade de descoberta de novos fármacos antimaláricos...

Componentes primários e secundários do rendimento de óleo de pinhão-manso / Primary and secondary yield components of the oil in physic nut (Jatropha curcas L.)

A definição dos critérios para seleção de materiais é especialmente importante para o cultivo do pinhão-manso (Jatropha curcas L.), pois subsidia a caracterização dos ideótipos mais adequados para o plantio e o progresso genético com a prática da seleção. O objetivo deste trabalho foi estimar, por meio de análise de trilha com diagrama em cadeia, os efeitos diretos e indiretos de sete características vegetativas e quatro características de qualidade da matéria-prima sobre o rendimento de óleo de pinhão-manso com 38 meses de cultivo. A produtividade de grãos e o teor de óleo apresentaram efeito direto e positivo sobre o rendimento de óleo, e o volume de copa mostrou-se como um dos principais componentes de efeito indireto e positivo sobre a variável principal. Na população de melhoramento avaliada, as estimativas dos efeitos diretos e indiretos indicaram que a seleção de plantas de maior rendimento de óleo deve considerar genótipos de maior produtividade de grãos e maior volume de copa, mantendo-se a variabilidade para as outras características avaliadas.

The definition of the most suitable plant selection criteria is especially important for Jatropha curcas L. as subsidies the genetic progress estimates and the ideotype characterization, described in terms of the traits that are thought to enhance genetic yield potential. The objective of this study was to estimate the direct and indirect effects of seven vegetative traits and four seed quality traits on J. curcas oil yield. The traits grain yield and the weight of the nuts showed direct and positive effect on the oil yield. The tree volume showed the major indirect and positive effect on the main variable through grain yield. The development of J. curcas with higher oil yield in the evaluated population has to consider the selection of plants with higher yield and tree volume, maintaining the variability of the grain quality traits.