Gastroprotective effects and antimicrobial activity of Lithraea molleoides and isolated compounds against Helicobacter pylori.

ETHNOPHARMACOLOGICAL RELEVANCE: Lithraea molleoides (Vell.) Engl. (Anacardiaceae) is a medicinal plant traditionally used in South America to treat various ailments, including diseases of the digestive system. AIM OF THE STUDY: To evaluate the in vivo antiulcer and antimicrobial activities against Helicobacter pylori of L. molleoides and its isolated compounds. MATERIALS AND METHODS: Methanolic extract 250 and 500 mg/kg, (LmE 250 and LmE 500, respectively) and infusions, 10 g and 20 g en 100mL (LmI 10 and LmI 20, respectively) of L. molleoides was evaluated for antiulcer activity against 0.6N HCl, 0.2N NaOH, 200mg/kg acetilsalicilic acid and absolute ethanol-induced gastric ulcers in rats. The degree of erosion in the glandular part of the stomach was assessed from a scoring system. Acute toxicity in mice was also evaluated. The antiulcer effect of the isolated compounds (catechol, mannitol, rutin, gallic acid, ferulic acid and caffeic acid, 100mg/kg) was evaluated against absolute ethanol-induced gastric ulcers in rats. The anti-Helicobacter pylori activity of L. molleoides and isolated compounds was performed using broth dilution methods. RESULTS: The LmE 250, LmE 500, LmI 10 and LmI 20 produced significant inhibition on the ulcer index in 0.6N HCl, 0.2N NaOH, 200mg/kg acetilsalicilic acid and absolute ethanol- induced gastric ulcers in rats. The isolated compounds, catechol, mannitol, rutin, ferulic acid and caffeic acid were active in absolute ethanol- induced gastric ulcers in rats. L. molleoides and different compounds showed antimicrobial activity in all strains tested. The lowest MIC value (0. 5 µg/mL) was obtained with catechol in six of eleven strains assayed. No signs of toxicity were observed with doses up to 2g/kg in an acute toxicity assay. CONCLUSION: These findings indicate that L. molleoides displays potential antiulcerogenic and antimicrobial activities and the identification of active principles could support the use of this plant for the treatment of digestive affections.

Caracterización por HPLC y FTIR de los extractos acuosos de tres especies diuréticas del centro-oeste argentino / Characterization by HPLC and FTIR of the aqueous extracts of three diuretic species from the Argentine center-west

Euphorbia serpens Kunth var. microphylla Müll. Arg. (Euphorbiaceae), Amaranthus muricatus (Moq.) Hieron. (Amaranthaceae) y Lithraea molleoides (Vell.) Engl. (Anacardiaceae) son plantas usadas tradicionalmente en el Cono Sur de América como diuréticas. Las dos primeras son hierbas denominadas vulgarmente "yerbas meonas", mientras que la última, un árbol perennifolio, es conocido como "molle de beber" o "molle dulce". El objeto de este trabajo es caracterizar los extractos acuosos de estas drogas vegetales, identificando y cuantificando manitol por HPLC, debido a que este alcohol sería el principal responsable de la actividad diurética que han mostrado las tres plantas. Se realizó además, la caracterización fisicoquímica de las especies vegetales por comparación de los espectros de FT-IR. Los cromatogramas obtenidos por HPLC muestran picos con tiempos de retención a 35,44 min (estándar) característicos para manitol, y el área por debajo de las respectivas curvas permitió establecer concentraciones respecto a materia seca entre 23,056 g Kg-1 en E. serpens var. microphylla; 4,638 g Kg-1 en L. molleoides; y 2,080 g Kg-1 en A. muricatus. Estas cifras explican las diferencias en la potencia diurética descripta en la bibliografía para las especies en estudio. Los espectros IR presentan una relación de áreas de las bandas CO/CH que resultó distintiva para las dos especies (8,42 para E. serpens var. microphylla; 9,28 para A. muricatus; y 11,18 para L. molleoides). El valor mayor correspondiente a L. molleoides indica mayor cantidad de compuestos oxigenados. Los datos espectrales obtenidos permiten contribuir a la caracterización de los extractos acuosos de estas especies y aportan datos para un control de calidad efectivo de las drogas vegetales y los medicamentos herbarios que los contengan en su formulación. (AU)

Morpho-anatomical alterations in plants of Lithraea molleoides (Vell.) Engl. submitted to flooding / Alterações morfoanatômicas em plantas de Lithraea molleoides (Vell.) Engl. submetidas ao alagamento - DOI: 10.4025/actascibiolsci.v29i1.408

Flooding effects in Lithraea molleoides plants were studied. Young plants were kept under drained and flooded soil over a period of 35 days. For growth and development analyses, the length and diameter of stem and main root and the dry weight of roots, stem, and leaves were measured. For anatomical studies, sections of fresh and fixed roots, stem bases and leaves were made using standard procedures in vegetal anatomy. The stress reduced the dry weight increment of plants without causing the death of roots or the abscission of leaves. In the stem base, flooding induced the hypertrophy of lenticels and the increase of intercellular space and reduction lower starch contents, in the cortex. Plants flooded displayed greater percentage of cortical intercellular space in the secondary roots and lower investment in secretory structure formation in the stem base. It can be suggested that flooding reduced the recourses allocation to growth. These recourses could be used in morphological alterations, such as hypertrophied lenticels and increase of intercellular spaces, that could contribute to plants survival during stress period, probably, due maintenance of aerobic respiration.

Visando contribuir para o conhecimento das estratégias de tolerância de espécies arbóreas à hipoxia, os efeitos do alagamento em plantas de Lithraea molleoides foram estudados. Indivíduos jovens foram mantidos em condições de solo drenado e alagado por 35 dias. Para as análises de crescimento e desenvolvimento, o comprimento e diâmetro do caule e raiz principal e o peso seco de raízes, caule e folhas foram medidos. Para os estudos anatômicos, foram realizados cortes de material fresco e fixado, de acordo com técnicas usuais em anatomia vegetal. As plantas alagadas apresentaram menor massa seca sem, contudo, ocorrer morte de raízes ou abscisão de folhas. Observou-se maior volume de espaços intercelulares nas raízes secundárias e na base dos caules dessas plantas, sendo que a última região apresentou lenticelas hipertrofiadas. As plantas alagadas apresentaram menor teor de amido na base do caule e menor investimento em estruturas secretoras. Sugere-se que o alagamento provocou redução na alocação de recursos para crescimento, os quais foram utilizados na produção de alterações morfológicas, como lenticelas hipertrofiadas e aumento dos espaços intercelulares. Essas alterações contribuíram para a sobrevivência das plantas durante o período de estresse, possivelmente por manter a respiração aeróbia