Efectos de Capsicum baccatum y C. frutescens sobre Atta cephalotes (Hymenoptera: Formicidae) y el hongo simbionte Leucoagaricus gongylophorus.

Las hormigas cortadoras de hojas son consideradas una plaga mayor en el Neotrópico, debido a las pérdidas económicas considerables que causan al cortar grandes cantidades de material vegetal, para cultivar su hongo simbionte. Su control se da principalmente a través de productos sintéticos con consecuencias adversas para el ambiente y la salud humana. En busca de alternativas, los extractos etanólicos de las hojas de Capsicum baccatum y C. frutescens (Solanaceae), fueron evaluados contra la hormiga cortadora de hojas Atta cephalotes y su hongo simbionte Leucoagaricus gongylophorus. Los resultados fueron prometedores, ya que ambos extractos exhibieron una combinación de actividad insecticida y antifúngica cuando fueron evaluados a concentraciones de 0,10, 0,25 y 0,50 % de m/v. De tal manera, C. baccatum se destacó por su actividad insecticida, mientras que C. frutescens presentó una mayor actividad antifúngica a altas concentraciones. Como los metabolitos secundarios presentes en plantas son responsables por su bioactividad, se llevaron a cabo evaluaciones fitoquímicas preliminares y cromatografía de gases acoplada a espectroscopia de masas (CGEM) para ambas especies. En el análisis cualitativo de metabolitos los grupos mayoritarios detectados fueron alcaloides, terpenoides y fenoles, los cuales son los compuestos que más frecuentemente citan en el manejo de la hormiga cortadora de hojas. Algunos de estos núcleos fueron confirmados por CGEM, tales como el cariofileno y el alcaloide conhidrina en C. baccatum y precursores de capsaicina en C. frutescens. De esta manera, ambas especies son consideradas como una alternativa prometedora para un manejo integrado de la hormiga cortadora de hojas más eficiente

Effects of two fractions of swietenia macrophylla and catechin on muscle damage induced by bothrops venom and PLA(2)

Plant natural products can attenuate the myonecrosis caused by Bothrops snake venom and their phospholipases A(2) (PLA(2)). In this study, we evaluated the effects of two fractions (F4 and F6) from Swietenia macrophylla and purified catechin on the muscle damage caused by a myotoxic PLA(2) from Colombian Bothrops asper venom (BaColPLA(2)) in mice and by Bothrops marmoratus venom from Brazil in mouse phrenic nerve-diaphragm muscle (PND) preparations in vitro. Male mice were injected with PLA(2) (50 mu g) in the absence or presence of F4, F6, and catechin, in the gastrocnemius muscle and then killed 3, 7, 14, and 28 h later for histopathological analysis of myonecrosis, leukocyte infiltration, and the presence of collagen. Fractions F4 and F6 (500 mu g) and catechin (90 mu g) significantly reduced the extent of necrosis at all-time intervals. These two fractions and catechin also attenuated the leukocyte infiltration on day 3, as did catechin on day 14. There was medium-to-moderate collagen deposition in all groups up to day 7, but greater deposition on days 14 and 28 in the presence of F6 and catechin. Bothrops marmoratus venom (100 mu g/mL) caused slight (25%) muscle facilitation after 10 min and weak neuromuscular blockade (64% decrease in contractile activity after a 120-min incubation). Pre-incubation of venom with F4 or F6 abolished the facilitation, whereas catechin, which was itself facilitatory, did not. All three fractions attenuated the venom-induced decrease in muscle contractions. These findings indicate that fractions and catechin from S. macrophylla can reduce the muscle damage caused by Bothrops venom and PLA(2). These fractions or their components could be useful for treating venom-induced local damage11

Plot-based collection of Florida plants for anticancer research and studies on Calyptranthes pallens.

Plot-based collection of Florida plants for anticancer research and studies on Calyptranthes pallens

Actividad antioxidante en musgos.

Mosses do not have the same anatomical barriers as vascular plants, so it has been suggested that the accumulation of certain compounds, such as flavonoids, have a fundamental role in its defense and adaptation to conditions causing oxidative stress. The antioxidant potential of six crude extracts of moss species was evaluated by the DPPH, ABTS, and FRAP methods. Of the evaluated species, Sphagnum sp. exhibited significant activity in the three methods tested, while Leptodontium luteum and Dicranum frigidum presented a relevant activity in at least one of the methods.Los musgos no poseen las mismas barreras anatómicas que las plantas vasculares, por lo que se ha sugerido que la acumulación de ciertos compuestos, como flavonoides, tiene un rol fundamental en su defensa y adaptación a condiciones causantes de estrés oxidativo. Se evaluó la capacidad antioxidante de los extractos totales de seis especies de musgos por los métodos DPPH, ABTS y FRAP. De las especies evaluadas, Sphagnum sp. presentó actividades significativas por los tres métodos, mientras que Leptodontium luteum y Dicranum frigidum presentaron actividad relevante en al menos uno de los métodos

Inhibitory effects of Swietenia macrophylla on myotoxic phospholipases A2

Activity-guided fractionation of an ethanol-soluble extract of the leaves of Swietenia macrophylla King, Meliaceae, led to several fractions. As a result, sample Sm13-16, 23 had the most promising activity against phospholipases A2 (PLA2), Asp49 and Lys49 types. This fraction inhibited PLA2 activity of the Asp49 PLA2, when aggregated substrate was used. On the other hand, this activity was weakly neutralized when monodispersed substrate was used. In addition, Sm13-16, 23 inhibited, in a dose dependent manner, the cytotoxicity, myotoxicity and edema induced by PLA2s, as well as the anticoagulant activity of Asp49 PLA2. Overall, this fraction exhibited a better inhibition of the toxic activities induced by the Lys49 PLA2than those caused by the Asp49 PLA2. The spectral data of Sm13-16, 23 suggested the presence of aromatic compounds (UV λ max (nm) 655, 266, and 219; IR λ max KBr (cm-1): ~ 3600-3000 (OH), 2923.07 and 1438.90 (C-H), 1656.69 (C = O), 1618.63 and 1607.67 (C-O), 1285.47772.60). We suggest that phenolic compounds could interact and inhibit the toxins by several mechanisms. Further analysis of the compounds present in the active fraction could be a relevant contribution in the treatment of accidents caused by snake envenomation

Effects of Capsicum baccatum and C. frutescens against Atta cephalotes (Hymenoptera: Formicidae) and the symbiotic fungus Leucoagaricus gongylophorus

Las hormigas cortadoras de hojas son consideradas una plaga mayor en el Neotrópico, debido a las pérdidas económicas considerables que causan al cortar grandes cantidades de material vegetal, para cultivar su hongo simbionte. Su control se da principalmente a través de productos sintéticos con consecuencias adversas para el ambiente y la salud humana. En busca de alternativas, los extractos etanólicos de las hojas de Capsicum baccatum y C. frutescens (Solanaceae), fueron evaluados contra la hormiga cortadora de hojas Atta cephalotes y su hongo simbionte Leucoagaricus gongylophorus. Los resultados fueron prometedores, ya que ambos extractos exhibieron una combinación de actividad insecticida y antifúngica cuando fueron evaluados a concentraciones de 0,10, 0,25 y 0,50 % de m/v. De tal manera, C. baccatum se destacó por su actividad insecticida, mientras que C. frutescens presentó una mayor actividad antifúngica a altas concentraciones. Como los metabolitos secundarios presentes en plantas son responsables por su bioactividad, se llevaron a cabo evaluaciones fitoquímicas preliminares y cromatografía de gases acoplada a espectroscopia de masas (CGEM) para ambas especies. En el análisis cualitativo de metabolitos los grupos mayoritarios detectados fueron alcaloides, terpenoides y fenoles, los cuales son los compuestos que más frecuentemente citan en el manejo de la hormiga cortadora de hojas. Algunos de estos núcleos fueron confirmados por CGEM, tales como el cariofileno y el alcaloide conhidrina en C. baccatum y precursores de capsaicina en C. frutescens. De esta manera, ambas especies son consideradas como una alternativa prometedora para un manejo integrado de la hormiga cortadora de hojas más eficiente.Leaf cutter ants are considered to be a major pest in the Neotropics, due to the considerable economic losses they cause by cutting large amounts of plant material to cultivate their symbiotic fungus. Their control is mainly achieved through synthetic products with adverse consequences to the environment and human health. In search for alternatives, the ethanolic extracts of leaves of Capsicum baccatum and C. frutescens (Solanaceae), were evaluated against medium size leaf cutter ant Atta cephalotes, and its symbiotic fungus Leucoagaricus gongylophorus. The results were promising as both plant extracts exhibited a combination of insecticidal and antifungal activity when evaluated at concentrations of 0.10, 0.25, and 0.50 % w/v. Thus, C. baccatum was shown to be the most promising as an insecticidal while, C. frutescens presented a better antifungal activity at high concentrations. Since secondary metabolites present in plants are responsible for their bioactivity, preliminary phytochemical tests and gas chromatography coupled with mass spectrometry (GCMS) of both species were carried out. In qualitative metabolite analysis, major groups detected were alkaloids, terpenoids and phenols, which are the compounds cited with the highest frequency in the management of the leaf cutter ant. Some nuclei were confirmed by GCMS, such as caryophyllene and the alkaloid conhidrine detected in baccatum, and precursors of capsaicin in C. frutescens. In this way, both species are considered promising leads for a more efficient integrated management of the leaf cutter ants