Desarrollo, caracterización y evaluación de formas farmacéuticas de uso en piel y mucosas que vehiculicen extractos vegetales con actividad antimicrobiana

El uso de plantas para curar enfermedades y cicatrizar heridas es una costumbre que data de miles de años y una herencia de las antiguas civilizaciones. A pesar de que una importante proporción de la biodiversidad vegetal del planeta se encuentra en el continente americano, son muy pocos los productos farmacéuticos desarrollados a partir de ella. Esta tesis tuvo como objetivo desarrollar y caracterizar formulaciones de aplicación tópica (geles, emulgeles y películas), para su uso en piel y mucosas, que vehiculicen una combinación de extractos vegetales con actividad antibacteriana y antiinflamatoria. Los extractos hidroalcohólicos de Lippia turbinata Griseb. y Lippia alba (Mill.) N. E. Brown se obtuvieron mediante lixiviación; se hizo la caracterización físico-química, se cuantificó el contenido de fenoles totales, se evaluó la actividad antibacteriana y antiinflamatoria de los extractos solos y su combinación. Los excipientes empleados para las formulaciones en gel y emulgel fueron: Carbopol® 934 y 940, PemulenTM TR1 y TR2, Politrap®, Sepigel® 305, carboximetilcelulosa sódica, metilcelulosa, hidroxietilcelulosa, Ceral PW, Ceral 10, alcohol estearílico, alcohol cetílico, alcohol cetoestearílico, ácido oleico, glicerina, propilenglicol. Al producto terminado se le realizó una caracterización de las propiedades físicas: características organolépticas, extensibilidad, viscosidad, pH, conductividad, perfil de textura, permeación y análisis microbiológico. En el caso de las películas se empleó hidroxipropilmetilcelulosa (HPMC), distintos tipos de Eudragit®, propilenglicol, glicerina, sorbitol y sacarina. Se realizó la caracterización mediante evaluación del aspecto, contenido de polifenoles, estudio de liberación, índice de humectación, resistencia a la rotura, espesor, mucoadhesividad y permeación. Luego fueron sometidos a estudios de estabilidad en distintas condiciones de temperatura y humedad. Los emulgeles probados no fueron estables, presentaron separación de fases, por lo que no fueron seleccionados para continuar su estudio. De los geles formulados, el gel con Sepigel® al 4% (p/p) presentó mejor aspecto, olor característico de las especies vegetales, de color marrón, sin presencia de grumos y con buena extensibilidad. Los geles tuvieron una permeación in vitro de la piel porcina de hasta un 30% y baja retención en el epitelio de ensayo (<15%). Además, no presentaron contaminación microbiana y fueron estables durante 18 meses. Con respecto a las formulaciones tipo película, el excipiente HPMC al 1% (p/p) fue el más adecuado para el fin propuesto. La película resultante presentó una superficie de apariencia lisa, brillosa, de color marrón, inodora, dulce y con sabor característico de los extractos vegetales. También conservó la actividad antibacteriana de los extractos, siendo estable en ambiente fresco (entre 8 y 25 ºC) y seco (<58% humedad relativa). Las películas mostraron baja permeabilidad in vitro en mucosa oral porcina (≤13%), con mayor porcentaje de retención en el epitelio (≤43%). Las películas no presentaron contaminación microbiológica durante 24 meses. Estos resultados demuestran la factibilidad de vehiculizar el extracto en una formulación de tipo gel y en películas, logrando conservar el efecto antibacteriano del extracto y manteniendo la estabilidad en el tiempo sin el uso de conservantes antimicrobianos.The use of plants to cure diseases and heal wounds is a custom that dates back thousands of years and a legacy of ancient civilizations. Although a significant proportion of the planet's plant biodiversity is found on the American continent, very few pharmaceutical products developed from it. This thesis aimed to develop and characterize topical application formulations (gels, emulgels and films), for use on skin and mucosa, and to transport a combination of plant extracts with antibacterial and anti-inflammatory activity. Hydroalcoholic extracts of Lippia turbinata Griseb. and Lippia alba (Mill.) N. E. Brown were obtained by leaching; the physical-chemical characterization was made, the content of total phenols was quantified, the antibacterial and anti-inflammatory activity of the extracts alone and their combination were evaluated. The excipients used for the gel and emulgel formulations were: Carbopol® 934 and 940, PemulenTM TR1 and TR2, Politrap® , Sepigel® 305, sodium carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, Ceral PW, Ceral 10, stearyl alcohol, cetyl alcohol, cetostearyl alcohol , oleic acid, glycerin, propylene glycol. The finished product was characterized by physical properties: organoleptic characteristics, extensibility, viscosity, pH, conductivity, texture profile, permeation, and microbiological analysis. In the case of films, hydroxypropylmethylcellulose (HPMC), different types of Eudragit® , propylene glycol, glycerin, sorbitol, and saccharin were used. Characterization was carried out by evaluating the appearance, polyphenol content, release study, wetness index, tear strength, thickness, mucoadhesiveness, and permeation. Then, they were subjected to stability studies in different conditions of temperature and humidity. The tested emulgels were not stable; they presented phase separation, so they were not selected to continue their study. Of the gels formulated, the gel with Sepigel® at 4% (w/w) presented a better appearance; a characteristic smell of plant species, brown, without the presence of lumps and with good extensibility. The gels had an in vitro permeation of porcine skin of up to 30% and low retention in the test epithelium (≤43%). The films did not show microbiological contamination for 24 months. These results demonstrate the feasibility of transporting the extract in a gel formulation and films, managing to preserve the antibacterial effect of the extract and maintaining stability over time without the use of antimicrobial preservatives.Fil: Pérez Zamora, Cristina Marisel. Universidad Nacional del Chaco Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin

Evaluation of the antibacterial synergism of two plant extracts belonging to Bignoniaceae family and development of a topical formulation

Fridericia caudigera and Cuspidaria convoluta (Bignoniaceae) species, which grow in the northwest of Argentina, have shown antibacterial effect against strains isolated from skin infections, and each one displayed synergism with commercial antibiotics. The aims of this work were to evaluate the antibacterial activity and toxicity of the combination of these two plant species, and to design a stable gel for topical use including the blend of extracts. The combination of extracts was evaluated for synergistic effects (chequerboard assay), genotoxicity (Ames test) and cytotoxicity (Artemia salina test). A gel was subsequently formulated with the combination of extracts using carboxymethylcellulose as a polymer. The following physicochemical characteristics of the gel formulation: pH, viscosity, spreadability and total phenol content, as well as resistance to severe temperature changes, biological activity (diffusion in agar), in vitro permeation (Franz cells) and primary dermal irritation (Draize test) were analyzed. The combination of extracts showed a synergistic effect on pathogenic bacteria and was not toxic in the in vitro tests. The gel was stable and retained the antimicrobial activity of the original extracts. The formulation proposed in this work could constitute an alternative for primary skin infections since it proved to be safe for topical administration.Fil: Torres, Carola Analía. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Pérez Zamora, Cristina Marisel. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Nuñez, María Beatriz. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Isla, Maria Ines. Universidad Nacional de Tucumán. Instituto de Bioprospección y Fisiología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Bioprospección y Fisiología Vegetal; ArgentinaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Zampini, Iris Catiana. Universidad Nacional de Tucumán. Instituto de Bioprospección y Fisiología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Bioprospección y Fisiología Vegetal; Argentin

Influence of herbal extracts in physicochemical properties and stability of antibacterial gels

The use of plants to treat diseases and heal wounds is a custom that dates back thousands of years and is a legacy of ancient civilizations. Although a significant proportion of the planet's plant biodiversity is found on theAmerican continent, there are very few pharmaceutical products developed from it. This work aimed to develop and characterize topical formulations (gels and emulgels), including a combination of plant extracts with recognized antibacterial activity. Hydroalcoholic extracts of Lippia turbinata Griseb. and Lippia alba (Mill.) N. E. Brown were obtained by leaching. The excipients used were Carbopol® 934 and 940, Sepigel® 305, sodium carboxymethylcellulose, methylcellulose, propylene glycol, and ethanol. The finished product was characterized by properties: organoleptic characteristics, extensibility, pH, texture profile, permeation performance, and microbiological quality. Then, they were subjected to stability studies in different conditions of temperature and humidity. They had a characteristic smell of plant species, color brown, without the presence of lumps, and with good extensibility. The gels had an in vitro permeation of porcine skin of up to 30% and low retention in the epithelium (<15%). They did not present microbial contamination and were stable for six months. Of the gels formulated, the gel with Sepigel® 4% (w/w) presented a better appearance. These results demonstrate the feasibility of transporting non-hydro soluble extracts in a gel formulation. All formulations are appropriate to preserve the antibacterial effect of original extracts. They maintain stability over time without the use of antimicrobial preservatives.Fil: Pérez Zamora, Cristina Marisel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral. Departamento de Ciencias Básicas y Aplicadas; ArgentinaFil: Michaluk, Ariel Germán. Universidad Nacional del Chaco Austral; ArgentinaFil: Torres, Carola Analía. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Mouriño, Viviana Silvia Lourdes. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chiappetta, Diego Andrés. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nuñez, María Beatriz. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; Argentina. Universidad Nacional del Chaco Austral. Departamento de Ciencias Básicas y Aplicadas; Argentin

Composición fitoquímica y cribado biológico de dos especies de Lophophytum

Las especies de Lophophytum son holoparásitas que crecen en raíces de árboles. Los objetivos del trabajo fueron explorar la composición química del túber de dos especies de Lophophytum y analizar la actividad antioxidante, antiinflamatoria y antilitiásica de sus extractos usando métodos in vitro. La composición química se determinó mediante pruebas histoquímicas, fitoquímicas y por TLC. Además, se determinó el perfil de compuestos fenólicos por HPLC-MS/MS. Se demostró presencia de metabolitos secundarios de reconocida actividad. Los resultados del HPLC-MS/MS permitieron identificar tentativamente catequina, luteolina y glucósidos de eriodictiol, naringenina y luteolina en el extracto de Lophophytum leandri y eriodictiol, naringenina, luteolina y sus derivados glicosilados en Lophophytum mirabile. Los extractos mostraron prometedora actividad antioxidante (DPPH, ABTS y β-caroteno-ácido linoleico), antiinflammatoria (inhibición de la 5-LOX) y antiurolitiásica (por TLC bioautográfica). Es de destacar que estos son los primeros resultados de composición fitoquímica y actividad biológica de L. mirabile. Sin embargo, se requieren estudios in vivo para corroborar dichas actividades.Lophophytum species are holoparasites that grow on tree roots. The objectives of the work were to explore the chemical composition of the tubers of two Lophophytum species and to analyze the antioxidant, anti-inflammatory and antilithiatic activity of their extracts using in vitro methods. The chemical composition was determined by histochemical, phytochemical and TLC tests. In addition, the profile of phenolic compounds was determined by HPLC-MS. The presence of secondary metabolites of recognized activity was demonstrated. The results of the HPLC-MS/MS allowed the tentative identification of catechin, luteolin and glycosides of eriodictyol, naringenin and luteolin in the extract of Lophophytum leandri and eriodictyol, naringenin, luteolin and their glycosylated derivatives in Lophophytum mirabile. The extracts showed promising antioxidant (DPPH, ABTS and β-carotenelinoleic acid), anti-inflammatory (inhibition of 5-LOX) and anti-urolytic (by bioautographic TLC) activity. It is noteworthy that these are the first results of the phytochemical composition and biological activity of L. mirabile. However, in vivo studies are required to corroborate these activities.Fil: Torres, Carola Analía. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Pérez Zamora, Cristina Marisel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Sato, Hector Arnaldo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Jujuy; ArgentinaFil: Nuñez, María Beatriz. Universidad Nacional del Chaco Austral; ArgentinaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

Formulation of cosmetic products from Cucurbita argyrosperma C. Huber seed oil

El presente trabajo tiene como objetivo aprovechar el aceite de las semillas de Cucurbita argyrosperma C. Huber (sin. Cucurbita mixta Pangalo), como fitoingrediente en la elaboración de productos cosméticos. El aceite empleado se obtuvo por extracción con soxhlet y se realizó su caracterización fisicoquímica. Se elaboraron emulgeles (O/W) variando el agente viscosante y emulgente. Las formulaciones logradas se valoraron mediante la evaluación de las propiedades organolépticas (color, olor, brillo), fisicoquímicas (pH, conductividad) y extensibilidad y fueron sometidas a estudios de estabilidad. Se obtuvieron productos tipo emulgel de color amarillento con ligero olor ceroso, con pH aceptable para la piel. Todas las formulaciones resultaron estables. Los resultados demostraron que las formulaciones propuestas permitieron incorporar el aceite de origen vegetal logrando un preparado cosmético de características y estabilidad aceptables.The objective of this work is to take advantage of the oil of the seeds of Cucurbita argyrosperma C. Huber (sin. Cucurbita mixta Pangalo), as a phytoingredient in the elaboration of cosmetic products. The oil used was obtained by extraction with soxhlet and its physicochemical characterization was carried out. Emulgels (O/W) were prepared by varying the viscosifying and emulsifying agent. The formulations achieved were evaluated by evaluating the organoleptic properties (color, odor, brightness), physicochemical (pH, conductivity) and extensibility and were subjected to stability studies. Emulgel type products with yellowish color with slight waxy odor were obtained, with acceptable pH for the skin. All the formulations were stable. The results showed that the proposed formulations allowed incorporating the oil of vegetable origin achieving a cosmetic preparation of acceptable characteristics and stability.Fil: Valenzuela, Gabriela Malena. Universidad Nacional del Chaco Austral; ArgentinaFil: Gruszyki, Mabel Rosalía. Universidad Nacional del Chaco Austral; ArgentinaFil: Pérez Zamora, Cristina Marisel. Universidad Nacional del Chaco Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Nuñez, María Beatriz. Universidad Nacional del Chaco Austral; ArgentinaFil: Chiappetta, Diego Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; ArgentinaFil: Giménez, María Cecilia. Universidad Nacional del Chaco Austral; Argentin

Mucilage of Opuntia ficus indica as natural excipient potential of cosmetic products

El mucílago de Opuntia es un fitoingrediente atractivo por su habilidad para retener agua ymodificar propiedades como viscosidad, elasticidad y textura. Los objetivos del trabajofueron evaluar las características fisicoquímicas, la actividad antioxidante y la potencialtoxicidad de mucílagos obtenidos de Opuntia ficus indica para su posible uso enfitocosmética. Las pencas fueron lavadas, despinadas, cortadas y secadas en estufa hastapeso constante. Para la obtención de los mucílagos, otra porción de las pencas cortadas fuelicuada con agua tibia (1:6) y dividida en tres fracciones. La fracción M1 fue macerada enbaño termostatizado, la M2 fue sometida a agitación a 6000 rpm, ambos procedimientos serealizaron por 1 h a 80°C, se filtraron y precipitaron con etanol (1:3). La fracción M3 partióde la misma técnica de M1, con una centrifugación previa a la precipitación. Los productosse secaron en estufa a 40 °C, se pulverizaron y caracterizaron por espectroscopía IR. Secuantificó el contenido de clorofilas y se determinaron los atributos de color (CIELAB). Secalculó la capacidad de retención de agua (CRA) y la solubilidad en distintos sistemas desolventes. Por último, se prepararon suspensiones (1% p/v) para medir pH, actividadsecuestrante de radicales libres con DDPH e irritabilidad in vitro mediante la técnica HETCAM.El contenido de agua superó el 90%. Los rendimientos de extracción fueron 1,15%(M1), 1,18 % (M2) y 0,49% (M3). Los espectros IR mostraron bandas típicas depolisacáridos. El contenido de clorofila fue superior en M1, mientras que resultó más bajoen M3. La CRA para los tres mucílagos fue cercana a 1 g/g. M3 mostró mejor solubilidadNaturalia Patagónica Vol. 16 (2020) 143-157. Aplicaciones del Mucílago de Opuntia ficus indica. en los distintos sistemas solventes. Todos los mucílagos presentaron un ángulo de tono (h*)amarillo-verdoso y alta luminosidad. Los valores de pH de las suspensiones estuvieron entre5,07 y 6,50. Si bien todos mostraron capacidad antioxidante, M2 presentó la mayor actividadde depuración. Ninguno resultó irritante. La agitación contribuyó a mejorar la actividadantioxidante y la centrifugación previa a la precipitación aumentó la solubilidad. Por lo tanto,en futuras extracciones se implementará una combinación de ambas técnicas.Opuntia mucilage is an attractive phytoingredient due to its ability to retain water and modify properties such as viscosity, elasticity and texture. The aims of this work were to evalúate the physicochemical characteristics, the antioxidant activity, and the potential toxicity of mucilages obtained from Opuntia ficus indica for its possible use in phytocosmetics. The cladodes were washed, de-stoned, cut, and put into a stove to constant weight. To obtain the mucilage, another portion of the cut cladodes was liquefied with warm water (1:6) and divided into three fractions. The MI fraction was macerated in a thermostatic bath, the M2 was stirred at 6000 rpm, both procedures were performed for 1 h at 80°C, filtered and precipitated with ethanol (1:3). For the M3 fraction the same technique was used as for MI but with a centrifugation before precipitation. The producís were dried in an oven at 40 °C, powdered and characterized by IR spectroscopy. Chlorophyll contení was quantifíed and color attributes (CIELAB) were determined. Water holding capacity (WHC) and solubility in different solvent Systems were calculated. Finally, suspensions (1% w/v) were prepared to measure pH, free radical scavenging activity with DDPH, and irritability in vitro by HETCAM method. The water content was over 90%. The extraction yields were 1.15% (MI), 1.18% (M2) and 0.49% (M3). IR spectra showed typical polysaccharide bands. The chlorophyll content was higher in MI, while it was very low in M3. The WHC for the three mucilages was cióse to 1 g/g. M3 showed better solubility in the different solvent Systems. All mucilages had a yellow-green tone angle (h*) and high brightness. The pH valúes of the suspensions were between 5.07 and 6.50. Although all showed antioxidant capacity, M2 presented the highest radical scavenging activity. None of them were irritating. Agitation contributed to improve antioxidant activity and centrifugation prior to precipitation increased solubility. Therefore, a combination of both techniques will be implemented in future extractions.Fil: Diez, Lisi Betiana. Universidad Nacional del Chaco Austral; ArgentinaFil: Pérez Zamora, Cristina Marisel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Michaluk, Ariel German. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Nuñez, María Beatriz. Universidad Nacional del Chaco Austral; ArgentinaFil: Torres, Carola Analía. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

Strategies to Improve Antimicrobial Activity of Natural Products: Approaches and Challenges

The plants possess a variety of bioactive compounds, which have an array of biological activities. Many synthetic drugs have their origin from some plant-based compounds. Most spices and herbs exert antimicrobial activity against different microorganisms (bacteria, yeasts, and molds) and can be used as food preservatives. Besides, some plants have antimicrobial effects against human and plant pathogens. In the last decades, plant-based antimicrobials have received considerable attention, because plants produce secondary metabolites in abundance, known to possess antimicrobial activity. Some of these metabolites are carbohydrates, alkaloids, tannins, steroids, terpenoids, flavonoids, and so on.Fil: Pérez Zamora, Cristina Marisel. Universidad Nacional del Chaco Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Torres, Carola Analía. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

In vitro antioxidant, antilipoxygenase and antimicrobial activities of extracts from seven climbing plants belonging to the Bignoniaceae

OBJECTIVES: This study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalymma marginatum (Cham.) DC., Amphilophium vauthieri DC., Cuspidaria convoluta (Vell.) A. H. Gentry, Dolichandra dentata (K. Schum.) L. G. Lohmann, Fridericia caudigera (S. Moore) L. G. Lohmann, Fridericia chica (Bonpl.) L. G. Lohmann and Tanaecium selloi (Spreng.) L. G. Lohmann. METHODS: The antioxidant activity was evaluated using three methods, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration (MIC) and minimal bactericidal/fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry. RESULTS: C. convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS+ radicals and reducing Fe3+ ion. These extracts showed a notable inhibition of lipoxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C. convoluta had higher total phenol content, better antioxidant activity and superior anti-inflammatory and antimicrobial activity. The main phenolic compounds found in this extract were coumaric and hydroxybenzoic acid derivatives and glycosylated and nonglycosylated flavones. CONCLUSION: Most of the extracts exhibited antioxidant activity as well as in vitro inhibition of lipoxygenase. The excellent antimicrobial activity of T. selloi and F. chica supports their use in traditional medicine as antiseptic agents. The extracts of F. caudigera and C. convoluta, both with notable biological activities in this study, could be used as herbal remedies for skin care. In addition, this study provides, for the first time, information about phenolic compounds present in C. convoluta.Fil: Torres, Carola Analía. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Pérez Zamora, Cristina Marisel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Nuñez, María Beatriz. Universidad Nacional del Chaco Austral; ArgentinaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

Evaluation of the antibacterial synergism of two plant extracts belonging to Bignoniaceae family and development of a topical formulation

Abstract Fridericia caudigera and Cuspidaria convoluta (Bignoniaceae) species, which grow in the northwest of Argentina, have shown antibacterial effect against strains isolated from skin infections, and each one displayed synergism with commercial antibiotics. The aims of this work were to evaluate the antibacterial activity and toxicity of the combination of these two plant species, and to design a stable gel for topical use including the blend of extracts. The combination of extracts was evaluated for synergistic effects (chequerboard assay), genotoxicity (Ames test) and cytotoxicity (Artemia salina test). A gel was subsequently formulated with the combination of extracts using carboxymethylcellulose as a polymer. The following physico- chemical characteristics of the gel formulation: pH, viscosity, spreadability and total phenol content, as well as resistance to severe temperature changes, biological activity (diffusion in agar), in vitro permeation (Franz cells) and primary dermal irritation (Draize test) were analyzed. The combination of extracts showed a synergistic effect on pathogenic bacteria and was not toxic in the in vitro tests. The gel was stable and retained the antimicrobial activity of the original extracts. The formulation proposed in this work could constitute an alternative for primary skin infections since it proved to be safe for topical administration

Evaluation of the antibacterial synergism of two plant extracts belonging to Bignoniaceae family and development of a topical formulation

Fridericia caudigera&nbsp;and&nbsp;Cuspidaria convoluta&nbsp;(Bignoniaceae) species, which grow in the northwest of Argentina, have shown antibacterial effect against strains isolated from skin infections, and each one displayed synergism with commercial antibiotics. The aims of this work were to evaluate the antibacterial activity and toxicity of the combination of these two plant species, and to design a stable gel for topical use including the blend of extracts. The combination of extracts was evaluated for synergistic effects (chequerboard assay), genotoxicity (Ames test) and cytotoxicity (Artemia salina&nbsp;test). A gel was subsequently formulated with the combination of extracts using carboxymethylcellulose as a polymer. The following physico- chemical characteristics of the gel formulation: pH, viscosity, spreadability and total phenol content, as well as resistance to severe temperature changes, biological activity (diffusion in agar),&nbsp;in vitro&nbsp;permeation (Franz cells) and primary dermal irritation (Draize test) were analyzed. The combination of extracts showed a synergistic effect on pathogenic bacteria and was not toxic in the&nbsp;in vitro&nbsp;tests. The gel was stable and retained the antimicrobial activity of the original extracts. The formulation proposed in this work could constitute an alternative for primary skin infections since it proved to be safe for topical administration