Aqueous extract of Hibiscus sabdariffa inhibits pedestal induction by enteropathogenic E. coli and promotes bacterial filamentation in vitro.

Diarrheic diseases account for the annual death of approximately 1.9 million children under the age of 5 years, and it is a major cause of work absenteeism in developed countries. As diarrheagenic bacteria, enteropathogenic Escherichia coli (EPEC) attach to cells in the small intestine, causing local disappearance of microvilli and inducing the formation of actin-rich pedestals that disrupt the intestinal barrier and help EPEC adhere to and infect intestinal cells. Antibiotics and other bioactive compounds can often be found by analyzing traditional medicines. Here a crude aqueous extract of Hibiscus sabdariffa, which typically grows in subtropical and tropical areas and is a popular medicinal tisane in many countries, was analyzed for antibacterial activity against EPEC. In standard microdilution assays, the extract showed a minimum inhibitory concentration of 6.5 mg/ml against EPEC growth. Time-kill kinetics assays demonstrated significant 24 h bactericidal activity at 25 mg/ml. The extract is able to impede pedestal induction. Not only did the extract inhibit preformed pedestals but it prevented pedestal induction as well. Remarkably, it also promoted the formation of EPEC filaments, as observed with other antibiotics. Our results in vitro support the potential of Hibiscus sabdariffa as an antimicrobial agent against EPEC.

Permeability Characteristics of a New Antifungal Topical Amphotericin B Formulation with γ-Cyclodextrins.

Amphotericin B is a low soluble broad-spectrum antifungal agent. Cyclodextrins can be added to amphotericin formulations to enhance both their solubility and antifungal properties. Semisolid amphotericin formulations containing gamma cyclodextrin (AGCD) were prepared and compared with two reference formulations-one of them without any solubility enhancer (A) and the other with DMSO (ADMSO). Rheological, the permeability through hairless mouse skin and antifungal characteristics of the different formulations were evaluated. All three semisolid formulations show low thixotropy characteristics. ADMSO was the formulation with the least consistency, lowest viscosity, and greatest extensibility. The AGCD formulation had the opposite behavior and had both the greatest consistency and viscosity and the lowest extensibility. The lowest permeability was obtained with the reference A formulation while both AGCD and ADMSO had a similar permeability enhancement. According to the antimicrobial in vitro efficacy trials, the AGCD formulation showed 45⁻60% more activity than the reference A formulation. It can be concluded that γ-cyclodextrin is a useful excipient to improve the solubility, permeability, and antifungal activity of amphotericin B in semisolid topical formulations.

Microbiología del agua mineromedicinal del Balneario de San Nicolás / Microbiology of the natural mineral water of San Nicolás Spa

Se han estudiado los microorganismos autóctonos y alóctonos de las aguas mineromedicinales del Balneario San Nicolás (Alhama de Almería). No se han encontrado bacterias patógenas ni indicadores fecales en 250 mL de agua. La microbiota autóctona está constituida, principalmente, por bacterias oligotrofas Gram positivas de la clase Firmicutes. El sondeo Sillero, utilizado en los tratamientos, presenta un número muy bajo de bacterias viables (<10 ufc/mL) que corresponden en su mayoría a cocos Gram positivos (93,3%) y a la especie Staphylococcus lugdunensis (40%). El sondeo San Marcos tiene una mayor diversidad microbiana, predominando los bacilos Gram positivos de la especie Bacillus licheniformis (32,4%) y los bacilos Gram negativos de la especie Cupriavidus pauculus (16,2%). En todas las muestras se han detectado microorganismos proteolíticos, amilolíticos, nitrificantes y amonificantes, así como bacterias halófilas y del hierro. También se han estudiado los biotapetes formados en las fuentes utilizadas para bebida, constituidos por una asociación de cianobacterias filamentosas y esféricas, así como del alga Cosmarium (AU)

Both the autochthonous and the allochthonous microorganisms of minero‐medicinal water from the San Nicolas spa (Alhama of Almería, Spain) have been analyzed. No pathogen bacteria or faecal indicators have been found in 250 mL of water. The autochthonous microbiota is mainly composed of oligotrophic Grampositive bacteria of the Firmicutes phylum. The Sillero sampling, used in the spa treatments, presents a very low count of viable bacteria (< 10 cfu / mL), being the most part of them Grampositive cocci (93.3%) of the Staphylococcus lugdunensis (40%) species. The San Marcos sampling presents a higher microbial diversity, predominantly Gram‐positive bacilli of the Bacillus licheniformis (32.4%) species and Gram‐negative bacilli of the Cupriavidus pauculus (16.2%) species. Proteolytic, amylolitic, nitrifying and ammonifying microorganisms have been detected in all samples, altogether with halophilic and iron bacteria. An analysis of the microbial mats growing in the spa drinking water sources shows that these consist of an association of spherical and filamentous cyanobacteria and the Cosmarium algae (AU)

Microbiología del agua mineromedicinal del Balneario de Villavieja / Microbiology of the natural mineral water of Villavieja Spa

Se ha estudiado la microbiota autóctona y alóctona del agua mineromedicinal del Balneario de Villavieja (Castellón). El número total de microorganismos en el agua ha sido de 4,7 x104/mL y el número de bacterias viables heterótrofas y oligotrofas de 103 ufc/mL. No se han encontrado indicadores fecales ni microorganismos patógenos en 250 mL de agua. La microbiota autóctona está constituida, principalmente, por bacilos Gram negativos no fermentadores del Phylum Proteobacteria (64,4%) y, en menor proporción, por bacilos Gram positivos (24,4 %) y cocos Gram positivos (6,7 %). Las especies más frecuentes han sido Pseudomonas pseudoalcaligenes (15,5 %) y Leifsonia aquatica (13,3 %). Se han detectado bacterias con actividades amonificantes, proteolíticas, amilolíticas y sulfato‐reductoras en 100 mL de agua que contribuyen a la autodepuración del agua (AU)

The autochthonous and alocthonous microbiota of the natural mineral water of Villavieja Spa have been studied. The total number of microorganisms in the water was of 4.7 x104 /mL and the number of heterotrophic and oligotrophic viable bacteria was 103 cfu/mL. Neither faecal indicators nor pathogenic microorganisms were found in 250 mL of water. The autochthonous microbiota mostly belongs to Gram‐negative bacilli, from the Phylum Proteobacteria (64.4%) and in smaller percentage to the Gram‐positive bacilli (24.4%) and cocci (6.7%). The most frequently found species were Pseudomonas pseudoalcaligenes (15.5%) and Leifsonia aquatica (13.3%). Moreover ammonifying, proteolytic, amylolytic and sulphato‐reducted bacteria have been detected in 100 mL of water, all of them involved in self‐purification process of water (AU)