Antibacterial activity of Calendula officinalis and Echinacea purpurea extracts against the causal agent of tomatoes' bacterial canker: Clavibacter michiganensis subsp. michiganensis / Actividad antibacteriana de los extractos de Calendula officinalis y Echinacea purpurea contra el agente causal del cancro bacteriano del tomate: Clavibacter michiganensis subsp. Michiganensis

We aimed to investigate the effects of Calendula officinalis and Echinacea purpurea extracts in terms of growth parameters, antibacterial activity and phenolic profile in tomato infected by Clavibacter michiganensis subsp. michiganensis (CmmT7). A significant difference was observed in E. purpuraextract, indicating the highest effects on plant height (27.25 cm), fresh plant weight (28.45 cm), root length (24.42 cm), and root weight (6.74 g) (p<0.05). Moreover, Calendula officinalis and Echinacea purpurea extracts showed significant inhibitory activity against CmmT7 (p<0.05). Among phenolic compounds, the only chlorogenic acid amounts were varied in the tomato seedlings leaves with C. officinalis extract (K3) + CmmT7, E. purpurea extract (E3) + CmmT7 and CmmT7 (p<0.01). Moreover, chlorogenic acid amount was approximately 9 times higher than in CmmT7-treated leaves when compared to control. The results showed that application of the extracts of these plants had a significant influence on bacterial canker and growth parameters.

Nuestro objetivo fue investigar los efectos de los extractos de Calendula officinalis y Echinacea purpurea en términos de parámetros de crecimiento, actividad antibacteriana y perfil fenólico en tomate infectado por Clavibacter michiganensis subsp. michiganensis (CmmT7). Se observó una diferencia significativa en el extracto de E. purpura, que indica los mayores efectos sobre la altura de la planta (27,25 cm), el peso de la planta fresca(28,45 cm), la longitud de la raíz (24,42 cm) y el peso de la raíz (6,74 g) (p<0,05). Además, los extractos de Calendula officinalis y Echinacea purpurea mostraron una actividad inhibidora significativa contra CmmT7 (p<0,05). Entre los compuestos fenólicos, las únicas cantidades de ácido clorogénico se variaron en las hojas de las plántulas de tomate con extracto de C. officinalis (K3) CmmT7, extracto de E. purpurea(E3) CmmT7 y CmmT7 (p<0.01). Además, la cantidad de ácido clorogénico fue aproximadamente 9 veces mayor que en las hojas tratadas con CmmT7 en comparación con el control. Los resultados mostraron que la aplicación de los extractos de estas plantas tuvo una influencia significativa sobre el cancro bacteriano y los parámetros de crecimiento.

Anacardium excelsum phytochemical analysis and in vitro antimicrobial activity against oral cavity microorganisms / Análisis fitoquímico y actividad antimicrobiana in vitro de Anacardium excelsum sobre microorganismos de cavidad bucal

ABSTRACT Infections of the oral cavity have a broad microbial etiological profile that varies according to each microenvironment in the mouth. Such infections often require antimicrobial treatment, which can lead to the development of resistance. There is thus a need to find new therapeutic strategies based on natural plant-derived compounds. The aim of this study was to determine the phytochemical nuclei and the antimicrobial effect of Anacardium excelsum leaf and stem extracts, and of fractions derived from the leaf extract, against Streptococcus mutans ATCC 25175, Staphylococcus aureus ATCC 35548, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 19433 and Candida albicans ATCC 10231. The plant material was collected from the Quindío Botanical Garden (Calarcá, Quindío-Colombia), located at an altitude of 1500 meters above sea level. Hydroalcoholic extracts of A. excelsum leaves and stems, and fractions of the hydroalcoholic leaf extract, were obtained by percolation extraction. Phytochemical nuclei were identified by thin layer chromatography. The antimicrobial activity of the extracts and fractions (at concentrations of 2, 5, 10, 20 and 40 mg / ml) against the five ATCC reference strains was evaluated using the well diffusion technique on Mueller-Hinton agar. The leaf extract showed no antimicrobial activity against E. coli, but it did show antimicrobial activity against S. mutans, S. aureus, E. faecalis and C. albicans, at a concentration of 10 mg/ml, with zones of inhibition of 9 to 11 mm. The ethyl acetate and acetone fractions obtained from A. excelsum leaf extract had greatest antimicrobial activity at 10 mg/ml. In conclusion, (1) the A. excelsum leaf extract, and the ethyl acetate and acetone fractions obtained from the leaf extract, had the greatest antimicrobial activity on all the study microorganisms, and (2) the phytochemical nuclei in the fractions (ethyl acetate and acetone) were found to contain phenolic-type compounds, tannins, triterpene-type terpenes and steroidal-type terpenes, which might explain the antimicrobial activity observed.

RESUMEN Las infecciones de la cavidad bucal se caracterizan por presentar un amplio perfil etiológico microbiano que varía de acuerdo a cada microambiente en boca. En muchos casos estas infecciones requieren tratamiento antimicrobiano que puede conducir al desarrollo de resistencia. Estos hechos en conjunto generan la necesidad de buscar nuevas estrategias terapéuticas, provenientes de compuestos naturales derivados de plantas. El objetivo de este estudio fue determinar los núcleos fitoquímicos y el efecto antimicrobiano de extractos de hojas y tallos, y de fracciones derivadas del extracto de hojas de Anacardium excelsum contra Streptococcus mutans ATCC 25175, Staphylococcus aureus ATCC 35548, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 19433 y Candida albicans ATCC 10231. El material vegetal se colectó del Jardín Botánico del Quindío (Calarcá, Quindío-Colombia), situado a una altura de 1500 msnm. Se obtuvieron extractos hidroalcohólicos de hojas y tallos, y fracciones a partir del extracto hidroalcohólico de hojas de A. excelsum mediante extracción por percolación. La identificación de los núcleos fitoquímicos fue realizado por cromatografía en capa delgada. La evaluación de la actividad antimicrobiana de extractos y fracciones, en concentraciones de 2, 5, 10, 20 y 40 mg/ml, frente a las 5 cepas de referencia ATCC, se realizó mediante la técnica de difusión con aplicación en pozo sobre agar Mueller-Hinton. El extracto de hojas no presentó actividad antimicrobiana sobre E. coli pero si sobre S. mutans, S. aureus, E. faecalis y C. albicans, en una concentración de 10 mg/ml, con halos de inhibición desde 9 a 11 mm, y las fracciones de acetato de etilo y acetona obtenidas del extracto de hojas de A. excelsum, presentaron mayor actividad antimicrobiana en una concentración de 10 mg/ml. En conclusión, 1. El extracto de hojas y las fracciones de acetato de etilo y acetona obtenidas del extracto de hojas de A. excelsum presentaron mayor actividad antimicrobiana sobre todos los microorganismos en estudio; 2. La evaluación de los núcleos fitoquímicos en las fracciones acetato de etilo y de acetona mostraron compuestos de tipo fenólico, taninos, terpenos del tipo triterpenos y terpenos del tipo esteroidal, que posiblemente expliquen la actividad antimicrobiana obtenida.

Antibacterial Activity of Polygonum Orientale Extracts Against Clavibacter Michiganensis subsp. michiganensis, the Agent of Bacterial Canker of Tomato Disease

Abstract Clavibacter michiganensis subsp. michiganensis (Cmm), which is a Gram positive bacterium, causes the bacterial canker of tomato disease. The purpose of the study was to evaluate the antibacterial activity of Polygonum orientale extracts against Cmm. In this study, firstly, effects of three extracting parameters (extractive time, extractive temperature, and solid to liquid ratio) of orthogonal experiment design L27 (313) were conducted. Secondly, survival rate was determined and inhibition zone of Cmm rescued post-stress was monitored. Finally, extracellular OD260nm value, extracellular protein content, conformational structure of membrane protein, extracellular alkaline phosphatase (AKP) activity, and ATPase activity were measured to investigate the antibacterial mechanism. Results of orthogonal experiment revealed that extractive time and extractive temperature had highly significant (P<0.01) effects on the antibacterial activity of P. orientale extracts. The optimum conditions were as follows: 10h of extractive time, 60°C of extractive temperature, and 1:20 (g:mL) of solid to liquid ratio. This study also demonstrated that the living cells of each sample from survival rate test had almost no resistance or adaptability, and rescued Cmm cells were much easier to be inhibited by P. orientale extracts. The results of antibacterial mechanism indicated that cell membrane and cell wall of Cmm were seriously damaged by P. orientale extracts, and P. orientale extracts reduced the intracellular ATPase activity dramatically. All these findings suggested that P. orientale extracts had a strong antibacterial activity to inhibit Cmm, and could be used for the ecological management of the bacterial canker of tomato disease.

Actividad antibacteriana de los extractos de Cymbopogon citratus, Elionurus sp. y Tagetes minuta contra bacterias que causan mastitis / Antibacterial activity of essential oils of Cymbopogon citratus, Elionurus sp. and Tagetes minuta against bacteria that cause mastitis

Introducción: el uso inadecuado de los antimicrobianos es un importante factor de resistencia a estos. En medicina veterinaria, este factor puede influir en el rendimiento de los animales, como en el caso de la mastitis bovina. Objetivo: evaluar la actividad antibacteriana de los aceites esenciales e hidroalcohólicos, de Cymbopogon citratus (DC.) Stapf., Elionurus sp. y Tagetes minuta L. contra bacterias aisladas de leche bovina. Métodos: la actividad antimicrobiana de plantas se evaluó utilizando la técnica de microdilución con la determinación de la concentración inhibitoria mínima. Resultados: los aceites esenciales eran más activos que los hidroalcohólicos, con valores de concentración mínima inhibitoria entre 0,39 y 6,32; 0,10 y 6,32 %; así como de 0,62 a 5 %, para Cymbopogon citratus, Elionurus sp. y Tagetes minuta, respectivamente; mientras que en los extractos hidroalcohólicos, excepto para Tagetes minuta, solo se inhibió Streptococcus uberis con Elionurus sp., pero el extracto hidroalcohólico de Cymbopogon citratus no mostró actividad antibacteriana. Conclusiones: los resultados sugieren el uso de estas plantas como un antimicrobiano natural, que es eficaz sobre bacterias de la mastitis bovina.

Introduction: the inappropriate use of antimicrobials is a major driver of antimicrobial resistance. In veterinary medicine, this factor can influence on animal performance, as in the case of bovine mastitis. Objective: this study is aimed to evaluate the antibacterial activity of essential oils and hydroalcoholic of Cymbopogon citratus (DC.) Stapf., Elionurus sp. and Tagetes minuta L. and the bacteria isolated from bovine milk. Methods: the antimicrobial activity of plants was evaluated using the microdilution technique, determining minimum inhibitory concentration values. Results: the essential oils were more active than the hydroalcoholic, with minimum inhibitory concentration values between 6,32 to 0,39 %; 0,10 and 6,32 %; as well as 0,62 to 5 %, for Cymbopogon citratus, Elionurus and T. minuta, respectively; while EHAs, except for Tagetes minuta, only inhibited Streptococcus uberis to Elionurus sp., being that the hydroalcoholic the Cymbopogon citratus showed no antibacterial activity. Conclusions: these results suggest the use of these plants as natural antimicrobial, being effective against bacteria of bovine mastitis.