Citrus aurontifolia and Cymbopogan flexuosus against Staphylococcus aureus and Escherichia coli

Abstract@#Introduction: Good hand hygiene is an important measure to avoid the transmission of infectious agents in the hospital and in the community. This study aimed to investigate the antimicrobial effects of Citrus aurantifolia (key lime) juice and the aqueous extract of Cymbopogan flexuosus leaves on the growth of Staphylocuccus aureus and Escherichia coli. Methods: Antimicrobial activity was quantitatively evaluated by spectrophotometry and viable cell count versus bacterial growth time. The efficacy of the plant extracts and the commercial hand wash product was also compared by measuring the number of bacterial colonies before and after using C. aurantifolia juice and commercial hand wash product. Results: In the kinetic growth study, C. aurantifolia juice and the aqueous extracts of C. flexuosus leaves effectively eliminated S. aureus and E. coli. C. aurantifolia juice also efficiently removed most of the microorganisms on the volunteers’ hand, indicating a significant finding in human trial compared to in vitro study. The percentage of microorganisms left after hand washing with C. aurantifolia juice was significantly reduced to 91.72 %, which was comparable with that of the commercial hand wash product (82.87 %). Conclusion: This study showed that these plant materials are promising alternatives for antibacterial agents in hand wash products. Further studies should be conducted on the use of C. aurantifolia juice as hand sanitiser given its antibacterial activities against endemic microbes

Validación preclínica del efecto antiinflamatorio tópico de cinco plantas medicinales / Preclinical validation of the topical anti-inflammatory effect of five medicinal plants

INTRODUCCIÓN: en Cuba y otros países del Caribe se reporta el uso tradicional de plantas medicinales para afecciones como amigdalitis, cefaleas, aftas, picaduras, artritis, entre otras, que tienen entre sus síntomas y signos dolor e inflamación; no existen suficientes estudios de validación preclínica para las preparaciones que se utilizan. OBJETIVOS: evaluar el efecto antiinflamatorio preclínico de preparaciones de 5 plantas medicinales de uso tradicional: Bidens pilosa L. (romerillo), Citrus aurantifolia (Christm) S. (limón), Hyptis verticillata J., Morinda citrifolia L. (noni) y Musa x paradisiaca L. (plátano). MÉTODOS: se empleó el modelo de edema de oreja inducido por aceite de Croton en ratones albinos OF-1 machos (20-25 g), 6 animales por grupo. Se aplicó tópicamente: zumo de partes aéreas frescas de Bidens pilosa(romerillo) y de fruto de Citrus aurantifolia (limón), decocciones al 30 % de partes aéreas secas de Hyptis verticillata, hojas frescas de Morinda citrifolia (noni), y de hojas frescas de Musa x paradisiaca (plátano), 10 µL en cada cara de oreja tratada. Se utilizó como control positivo dexametasona 0,1 mg/oreja. RESULTADOS: se obtuvo una reducción del edema inducido por aceite de Croton con las preparaciones de zumo de Citrus aurantifolia y las decocciones al 30 % de Morinda citrifolia y Musa x paradisiaca; con un considerable porcentaje de inhibición para cada una de ellas. El zumo de Bidens pilosa y la decocción 30 % de Hyptis verticillatano redujeron significativamente la formación del edema. CONCLUSIONES: los resultados experimentales permiten la validación preclínica de la actividad antiinflamatoria del zumo de Citrus aurantifolia y las decocciones a 30 % de Morinda citrifolia y Musa x paradisiaca, así como su empleo tradicional, no siendo así para el zumo de Bidens pilosa y la decocción al 30 % de Hyptis verticillata.

INTRODUCTION: the use of medicinal plants for the treatment of conditions such as tonsilitis, headaches, aphtas, insect bites and arthritis, has been reported in Cuba and other Caribbean countries. Pain and inflammation are among the signs and symptoms of these conditions. There are not enough studies about the preclinical validation of the preparations used. OBJECTIVES: evaluate the preclinical anti-inflammatory effect of preparations from five medicinal plants of traditional use: Bidens pilosa L. (romerillo), Citrus aurantifolia (Christm) S. (lemon), Hyptis verticillata J., Morinda citrifolia L. (noni) and Musa x paradisiaca L. (banana). METHODS: the Croton oil ear edema test model was used in male albino OF-1 mice (20-25 g), 6 animals per group. Juice from fresh aerial parts of Bidens pilosa (romerillo) and from the fruit of Citrus aurantifolia (lemon), 30 % decoctions of dry aerial parts of Hyptis verticillata, fresh leaves of Morinda citrifolia (noni), and fresh leaves of Musa x paradisiaca (banana), 10 µL, were topically applied on both sides of the ear being treated. Dexamethasone 0.1 mg/ear was used as positive control. RESULTS: Citrus aurantifolia juice preparations and the 30 % Morinda citrifolia and Musa x paradisiaca decoctions reduced Croton oil ear edema with a high inhibition percentage. Bidens pilosa juice and the 30 % Hyptis verticillatadecoction did not reduce edema formation significantly. CONCLUSIONS: experimental results support the preclinical validation of the anti-inflammatory activity of Citrus aurantifolia juice and the 30 % decoctions of Morinda citrifolia and Musa x paradisiaca, as well as their traditional use. Bidens pilosa juice and the 30 % decoction of Hyptis verticillata are not validated.

Efectos antioxidantes de una mezcla de principios activos de origen natural con actividad potencial en el tratamiento del vitiligo / Antioxidant effect of a mixture of natural origin with potential use in vitiligo

Se ha propuesto que el estrés oxidativo estaría involucrado en la patogénesis de la degeneración del melanocito en el vitiligo, donde se ha demostrado un desequilibrio tisular del sistema óxido-reducción. Estos hallazgos han promovido la utilización de nuevos tratamientos que contribuyan al equilibrio de antioxidantes en la epidermis afectada. Una nueva formulación de origen vegetal que contiene extractos de Pimenta racemosa, Cucumis melo y Citrus aurantifolia fue estudiada en un ensayo clínico experimental, aleatorizado y a doble ciego en pacientes con vitiligo vulgar estable con resultados satisfactorios. En el presente trabajo se evaluó la mezcla de principios activos en modelos experimentales in vitro, básicamente sus efectos antioxidantes sobre los fosfolípidos de membrana y sobre mediadores redox de interés en la fisiopatología del vitiligo. El extracto ensayado posee efectos inhibitorios de la peroxidación lipídica espontánea de fosfolípidos. Presenta actividad catalítica frente al H2O2 y actividad secuestradora de radicales libres, particularmente del radical hidroxilo, uniéndose al hierro, de forma que impide la formación de este radical. Adicionalmente, posee efectos fotoprotectores. Dados estos resultados, parece probable que el efecto observado en la clínica para esta combinación de principios activos naturales esté mediado por la mejora del sistema redox del entorno del melanocito.

Oxidative stress has been proposed as a part of the pathological mechanisms of melanocyte degradation invitiligo. It has been demonstrated a redox disruption inaffected areas. New therapeutically approach based onthese facts has been proposed recently. A novel combination of natural extracts (Pimenta racemosa, Cucumis melo, and Citrus aurantifolia) has been successfully tested in a double blind clinical assay in vitiligo. In the present manuscript it has been tested this mixture in in vitro assays, basically in the inhibition of phospholipids oxidation and related assays on redox mediator, involving in vitiligo physiopathology. The sample showed an antioxidant effect when assayed on spontaneous lipid peroxidation test in phospholipids. Inaddition the extract acted as a scavenger of H2O2, and free radicals, in particular hydroxyl radical by a mechanisms involving iron quenching. A photo protective effect of the sample has been also demonstrated. Insummary, our results shown that the modification of melanocyte redox environment may explain, at least inpart, the favorable clinical effects of this natural combination in vitiligo.

Complete ¹H and 13C NMR assignments and anti fungal activity of two 8-hydroxy flavonoids in mixture

A mixture of the two new flavonols 8-hydroxy-3, 4', 5, 6, 7-pentamethoxyflavone (1) and 8-hydroxy-3, 3', 4', 5, 6, 7-hexamethoxyflavone (2) was isolated from a commercial sample of Citrus aurantifolia. An array of one- (¹HNMR, {¹H}-13C NMR, and APT-13C NMR) and two-dimensional NMR techniques (COSY, NOESY, HMQC and HMBC) was used to achieve the structural elucidation and the complete ¹H and 13C chemical shift assignments of these natural compounds. In addition, the antifungal activity of these compounds against phytopathogenic and human pathogenic fungi was investigated.

Os flavonóis 8-hidroxi-3, 4', 5, 6, 7-pentametoxiflavona (1) e 8-hidroxi-3, 3', 4', 5, 6, 7-hexametoxiflavona (2) foram isolados em mistura a partir de uma amostra comercial de Citrus aurantifolia. A determinação estrutural e a inequívoca atribuição dos sinais de deslocamento químico dos átomos de hidrogênio e carbono destes compostos naturais foram realizadas através da análise dos espectros de RMN 1D e 2D, incluindo COSY, NOESY, HMQC e HMBC. Em adição, a atividade antifúngica destes compostos contra fungos patogênicos também foiinvestigada.