Inhibitory effect of Quassia amara Linn. crude bark extract on Entamoeba histolytica in vitro

BACKGROUND: Entamoeba histolytica is an important etiologic agent of diarrhea. Globally, it is estimated to infect 40 to 50 million people and cause 40,000 to 100,000 deaths per year. Metronidazole is effective but can cause adverse reactions in certain individuals. In search of alternatives, traditional medicinal plants are being studied. Several plants in Family Simaroubaceae have shown anti-amoebic activity. Quassia amara, a member of this family has not been tested.OBJECTIVE: To determine the effect of Q. amara crude extract on Entamoeba histolytica in vitro.METHODS: Initial testing of 104 µg/ml ethanolic bark extract was performed. Counts were made after 72 hours. Three trials in triplicates were performed.Nine (9) dilutions of extract were then tested (18.8 to 5,00 µg/ml). Test tubes were checked for viable amoeba after 24-hour and 72-hour incubation. Minimum inhibitory concentrations (MIC) were determined for the two incubation periods. At least two trials in triplicates for each dilution were performed. metronidazole served as positive control.RESULTS: At 104 µg/ml incubated for 72 hours, no viable amoeba was obtained and counted. The MIC after 24 hours was 5,000 µg/ml, while the MIC at 72 hours was 37.5 µg/ml.CONCLUSION: Q. amara crude extract has inhibitory effects on E. histolycain vitro.

Anti-hiperglycemic effect of Quassia amara (Simaroubaceae) in normal and diabetic rats / Efeito anti-hiperglicêmico de Quassia amara (Simaroubaceae) em ratos normais e diabéticos

The anti-hyperglycemic effect of wood powder of Quassia amara (QA) was evaluated in normal and in alloxan diabetes-induced rats. After a 12 h fast and glycemic check, the animals were orally given 0.9% of saline (control group), metformin (500 mg/kg) or QA (200 mg/kg) and, 30 minutes later, they received an oral glucose dose (1g/kg). The blood glucose level was measured after 30, 60, 90 and 120 minutes. From the oral glucose dose, QA showed anti-hyperglycemic effects, similar to metformin, only in the diabetic animals (p<0.01) when compared to the control group. Although the anti-hyperglycemic mechanism of action of QA was not investigated, a mechanism similar to metformin can be suggested, since both presented similar results for the conditions tested, that is, normal and diabetic rats. It is believed that the use of QA in diabetics could help to control the blood glucose levels and be useful as an alternative therapy.

O efeito anti-hiperglicemiante do pó do lenho de Quassia amara (QA) foi avaliado em ratos normais e diabéticos aloxana induzidos. Após jejum de 12 horas e verificação da glicemia, os animais receberam administração oral de salina 0.9% (grupo controle), metformina (500 mg/kg) ou QA (200 mg/kg) e 30 minutos depois carga oral de glicose (1g/kg). A glicemia foi medida nos próximos 30, 60, 90 e 120 minutos. A partir da carga oral de glicose, a QA mostrou efeito anti-hiperglicemiante, similar a metformina, somente nos animais diabéticos (p<0.01) quando comparados ao grupo controle. Embora o mecanismo de ação anti-hiperglicemiante da QA não tenha sido investigado, podemos sugerir um mecanismo semelhante à metformina, visto que ambos apresentaram resultados similares nas duas condições testadas, ou seja, animais normais e diabéticos. Acredita-se que o uso de QA, em diabéticos, possa auxiliar no controle da glicemia e servir como terapia alternativa.

Parámetros micrográficos para la identificación de leño, corteza y hoja de Quassia amara L. (Simaroubaceae) / Micrographic parameters for identification of Quassia amara L., wood, bark and leaf

Quassia amara L. popularly known as “quasia”, is a shrubby plant from Tropical America. The wood, bark and leave are used in either folk medicine or in procuring phytotherapeutic drugs. The aim of the present work was to analize morphoanatomical and micrographic features which might provide assistance in the identification, analysis and standardization of Quasia amara L wood, bark and leaves. Results. Anatomical study showed white yellowish and diffuse porous wood, confluent paratracheal parenchyma. Rays width 1 cell wide and 8-30 cells high. CaOx crystals are absent. Cortex, 1-4 mm thick, a periderm up to 12 layers phellem cells. Leaf, hipostomatic with dorsiventral mesophyll and high number of sclerosed idioblasts.

Quassia amara L. popularmente conocida como “quasia” es un planta arbustiva de América Tropical. El leño, corteza y hojas son usadas tanto en medicina popular como en la obtención de drogas fitoterapéuticas. El objetivo del presente trabajo es analizar características morfoanatómicas y micrográficas las cuales provean asistencia en la identificación, análisis y estandarización de la madera, corteza y hojas de Quassia amara L. Resultados. El estudio anatómico mostró leño, blanco amarillento, de porosidad difusa. Parénquima paratraqueal confluente. Radios de 1 célula de ancho y 8-30 hileras de alto. Faltan cristales CaOx. Corteza, 1-4 mm de espesor, una peridermis de hasta 12 estratos de células de súber. Hoja, hipoestomática, con mesófilo dorsiventral, con elevado número de idioblastos esclerosados.

Phagodeterrence by Quassia amara (Simaroubaceae) wood extract fractions on Hypsipyla grandella (Lepidoptera: Pyralidae) larvae

In Latin America and the Caribbean, precious wood species like mahoganies (Swietenia spp.) and cedars (Cedrela spp.) are seriously injured by the mahogany shootborer, Hypsipyla grandella (Zeller) (Lepidoptera: Pyralidae) larva, which bores into the main shoot of trees. In previous experiments focused on searching for a preventive method for managing this pest, a wood extract of bitterwood, Quassia amara L. ex Blom (Simaroubaceae) had been shown to cause phagodeterrence to larvae. Therefore, three fractions (water, methanol and diethyl ether) of a wood extract were tested for their phagodeterrence to larvae, by means of laboratory and greenhouse trials. Phagodeterrence was assessed by determining their effect on foliage consumption, mortality and signs of damage (number of orifices, sawdust piles, fallen shoots, number of tunnels and tunnel length) caused by larvae on Spanish cedar (C. odorata). Both the methanol and diethyl ether fractions caused phagodeterrence, by strongly reducing foliage consumption and signs of damage, while not causing larval mortality. The lowest concentration at which phagodeterrence was detected for the methanol fraction corresponded to 0.0625%, which is equivalent to a 1.0% of the bitterwood crude extract. However, results with the diethyl ether fraction were unsatisfactory, as none of the treatments differed from the solvent, possibly because of an adverse effect of the solvent on foliar tissues. Phagodeterrent principles from Q. amara derivatives may play an important role in dealing with H. grandella if they are complemented with other integrated pest management preventative tactics. Rev. Biol. Trop. 59 (1): 487-499. Epub 2011 March 01.

En América Latina y el Caribe, algunas especies que son fuente de maderas preciosas, como las caobas (Swietenia spp.) y cedros (Cedrela spp.), son seriamente dañadas por la larva de Hypsipyla grandella, la cual barrena el brote principal de los árboles. En experimentos previos orientados hacia la búsqueda de un método preventivo para manejar esta plaga, un extracto de la madera de hombre grande, Quassia amara (Simaroubaceae), había demostrado causar fagodisuasión a la larva. Por tanto, tres fracciones de un extracto de la madera de dicho árbol (agua, metanol y éter dietílico) fueron evaluadas en cuanto a su efecto fagodisuasivo sobre las larvas, mediante experimentos de laboratorio e invernadero. Dicho efecto se determinó según el consumo de follaje, la mortalidad y los signos de daño (número de orificios, montículos, brotes caídos, número y longitud de túneles) causados por las larvas en arbolitos de cedro amargo (C. odorata). Tanto la fracción de metanol como la de éter dietílico causaron fagodisuasión, pues redujeron fuertemente el consumo de follaje y los signos de daño, sin matar las larvas. La menor concentración de la fracción metanólica a la cual se detectó fagodisuasión correspondió a 0.0625%, la cual equivale al 1.0% del extracto crudo de hombre grande. Por su parte, los resultados con la fracción de éter dietílico fueron insatisfactorios, ya que ninguna de las concentraciones difirió del disolvente, quizás debido a un efecto adverso del mismo sobre los tejidos foliares. Los principios fagodisuasivos de los derivados Q. amara podrían jugar un papel importante para manejar a H. grandella, si fueran complementados con otras tácticas preventivas de manejo integrado de plagas.

Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae) adults: III. Quassia amara (Simaroubaceae)

Bemisia tabaci is a key virus vector on several crops worldwide. Then, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period). Thus, the crude extract and four fractions thereof (water, water: methanol, methanol, and diethyl ether) of bitterwood (Quassia amara, Simaroubaceae) were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract and some fractions exerted such effect on the insect. In the former case (in sleeve cages), all fractions caused deterrence at doses as low as 0.1 % (methanol), 0.5 % (water: methanol and diethyl ether), and 1% (water). In the latter case (plants exposed in a greenhouse) the methanol fraction stood out, followed by the diethyl ether fraction. Nonetheless, none of the fractions performed better than the deterrent control (mineral oil). Rev. Biol. Trop. 56 (4): 2131-2146. Epub 2008 December 12.

En el plano mundial, Bemisia tabaci es un importante vector de virus en numerosos cultivos. Un enfoque preventivo para enfrentar las epidemias virales podría ser el empleo de sustancias repelentes o fagodisuasivas en las etapas tempranas del desarrollo de las plantas (período crítico). Tanto el extracto crudo como cuatro fracciones (agua, agua: metanol, metanol, y éter dietílico). Evaluamos extractos del árbol llamado "hombre grande" (Quassia amara, Simaroubaceae) fueron evaluadas en cuanto a su actividad fagodisuasiva sobre los adultos de B. tabaci, usando tomate, en condiciones de invernadero, utilizando plantas de tomate, en Turrialba, Costa Rica. Tanto los experimentos de escogencia irrestricta e irrestrictam, el extracto crudo y algunas fracciones mostraron dicha actividad. En los primeros experimentos (en jaulas de manga), todas las fracciones causaron fagodisuasión a dosis de apenas 0.1% (metanol), 0.5% (agua: metanol y éter dietílico) y 1% (agua). En los segundos (plantas expuestas dentro de un invernadero) sobresalió la fracción metanólica, seguida por la de éter dietílico. Sin embargo, ninguna de las fracciones superó al testigo fagodisuasivo (aceite mineral).