Enzymatic Synthesis of a Diene Ester Monomer Derived from Renewable Resource.

The total or partial substitution of fossil raw materials by biobased materials from renewable resources is one of the great challenges of our society. In this context, the reaction under mild condition as enzyme-catalyzed esterification was applied to investigate the esterification of the biobased 10-undecenoic acid with 2-hydroxyethyl methacrylate (HEMA) to obtain a new diene ester monomer. The environmentally friendly enzymatic reaction presented up to 100% of conversion; moreover, the production of possible by-products was minimized controlling reaction time and amount of enzyme. Furthermore, the presence of chloroform was evaluated during the enzymatic reactions and despite high conversions with higher enzyme concentration, the solvent-free system showed fast kinetics even with 1.13 U/g substrates. In addition, the commercial immobilized lipases Novozym 435 and NS 88011 could be applied for up to 10 cycles keeping conversions about 90%. The scale-up of the reaction was possible and a purification procedure was applied in order to isolate the diene ester monomer 2-(10-undecenoyloxy)ethyl methacrylate, preserving its double bonds, which could allow a potential use of this product in the synthesis of new renewable polymers through techniques as metathesis, thiol-ene, or free-radical polymerization.

Validación de los métodos para control de calidad de los ingredientes activos en Fungirex crema / Validation of the quality control methods for active ingredients of Fungirex cream

Introducción: Fungirex crema es un producto que contiene dos fármacos: ácido undecilénico y undecilenato de zinc en una base adecuada. Como se trata de un producto que no aparece en las monografías oficiales de las farmacopeas, se proponen métodos analíticos sencillos capaces de cuantificar los analitos de interés en la crema, útiles para la liberación de los lotes de crema recién elaborados.Objetivo: validar dos métodos volumétricos para control de calidad de los ingredientes activos presentes en Fungirex crema. Métodos: se propuso una volumetría de neutralización directa para cuantificar ácido undecilénico previa extracción del analito y la complejometría con EDTA para undecilenato de zinc. Atendiendo a la clasificación de ambos métodos en la categoría I, se realizó la validación de ambos métodos a través de los parámetros: especificidad, linealidad, exactitud, precisión y rango. Resultados: se corroboró la ausencia de interferencia de los restantes componentes de la matriz. Los criterios de aceptación establecidos para linealidad, exactitud y precisión se cumplieron satisfactoriamente para los dos métodos en estudio, por lo que fueron válidos en el rango de 50 a 150 por ciento (método por volumetría de neutralización: 25,6-76,8 mg/g y método por complejometría: 111,1-333,3 mg/g). Conclusiones: los métodos volumétricos propuestos fueron lineales, precisos, exactos y específicos para realizar el control de calidad de Fungirex crema en base al contenido de ácido undecilénico y undecilenato de zinc(AU)

Introduction: Fungirex cream is a two-drug product, that is, undecylenic acid and zinc undecylenate over a suitable basis. Since this is a product not documented in the official monographs of the pharmacopeae, simple analytical methods were suggested for quantitation of analytes of interest in the cream, which are useful for release of newly prepared cream batches. Objective: to validate two volumetric methods for the quality control of active ingredients in Fungirex cream. Methods: a direct neutralization volumetric method was suggested to quantitate undecylenic acid after the analyte extraction and EDTA complexometry for zinc undecylenate . According to the classification of both methods in the category I, they were validated through the parameters specificity, linearity, accuracy, precision and range. Results: the non-interference of the rest of the matrix components was corroborated. The set acceptance criteria for linearity, accuracy and precision were satisfactorily met for the two study methods, so they were valid in the 50-150 percent range (neutralization volumetry method: 25.6-76.8 mg/g and complexometry method 111.1-333,3 mg/g). Conclusions: the suggested volumetric methods were linear, specific, precise, and accurate for the quality control of Fungirex cream based on the undecylenic acid and zinc undecylenate content(AU)

Validación de los métodos para control de calidad de los ingredientes activos en Fungirex crema / Validation of the quality control methods for active ingredients of Fungirex cream

INTRODUCCIÓN: Fungirex crema es un producto que contiene dos fármacos: ácido undecilénico y undecilenato de zinc en una base adecuada. Como se trata de un producto que no aparece en las monografías oficiales de las farmacopeas, se proponen métodos analíticos sencillos capaces de cuantificar los analitos de interés en la crema, útiles para la liberación de los lotes de crema recién elaborados. OBJETIVO: validar dos métodos volumétricos para control de calidad de los ingredientes activos presentes en Fungirex crema. MÉTODOS: se propuso una volumetría de neutralización directa para cuantificar ácido undecilénico previa extracción del analito y la complejometría con EDTA para undecilenato de zinc. Atendiendo a la clasificación de ambos métodos en la categoría I, se realizó la validación de ambos métodos a través de los parámetros: especificidad, linealidad, exactitud, precisión y rango. RESULTADOS: se corroboró la ausencia de interferencia de los restantes componentes de la matriz. Los criterios de aceptación establecidos para linealidad, exactitud y precisión se cumplieron satisfactoriamente para los dos métodos en estudio, por lo que fueron válidos en el rango de 50 a 150 por ciento (método por volumetría de neutralización: 25,6-76,8 mg/g y método por complejometría: 111,1-333,3 mg/g). CONCLUSIONES: los métodos volumétricos propuestos fueron lineales, precisos, exactos y específicos para realizar el control de calidad de Fungirex crema en base al contenido de ácido undecilénico y undecilenato de zinc(AU)

INTRODUCTION: Fungirex cream is a two-drug product, that is, undecylenic acid and zinc undecylenate over a suitable basis. Since this is a product not documented in the official monographs of the pharmacopeae, simple analytical methods were suggested for quantitation of analytes of interest in the cream, which are useful for release of newly prepared cream batches. OBJECTIVE: to validate two volumetric methods for the quality control of active ingredients in Fungirex cream. METHODS: a direct neutralization volumetric method was suggested to quantitate undecylenic acid after the analyte extraction and EDTA complexometry for zinc undecylenate . According to the classification of both methods in the category I, they were validated through the parameters specificity, linearity, accuracy, precision and range. RESULTS: the non-interference of the rest of the matrix components was corroborated. The set acceptance criteria for linearity, accuracy and precision were satisfactorily met for the two study methods, so they were valid in the 50-150 percent range (neutralization volumetry method: 25.6-76.8 mg/g and complexometry method 111.1-333,3 mg/g). CONCLUSIONS: the suggested volumetric methods were linear, specific, precise, and accurate for the quality control of Fungirex cream based on the undecylenic acid and zinc undecylenate content(AU)

Effects of undecylenic acid released from denture liner on Candida biofilms.

Denture liners (DL) are easily colonized by Candida spp. In an attempt to prevent biofilm colonization, manufacturers have incorporated undecylenic acid (UDA) into DL. In this in vitro study, the effects of UDA released from DL on Candida biofilms were investigated. The concentrations of UDA released from commercial DL were determined by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentration (MIC) and minimum fungistatic concentration (MFC) tests were performed for C. albicans or C. glabrata, with UDA for comparison with the concentrations released from DL. Specimens of DL with (experimental group) and without UDA (control group) were fabricated, and Candida biofilms were developed on DL surfaces. Biofilms were evaluated by cell counts, metabolic activity, structure, and secretion of proteinase or phospholipase. The concentrations of UDA released were within the MIC and MFC ranges. In the presence of UDA, C. albicans biofilms were thinner and had lower numbers of viable and active cells, although no significant enzymatic changes were observed relative to the control group (p > 0.05). In contrast, C. glabrata biofilms exhibited higher cell counts and greater metabolic activity and also increased proteinase activity in the presence of UDA relative to the control group (p < 0.05). Overall, UDA did not prevent Candida biofilm formation.

Efecto teratogénico y toxico de ácidos grasos de cadena corta insaturados, en Rhodnius prolixus / Teratogenic and toxic effect of unsaturated fatty acids of short chain, in Rhodnius prolixus

Se estudia el papel teratogénico de dos ácidos grasos insaturados de cadena corta, ácido octinoico y ácido undecilénico, sobre insectos de metamorfosis hemimetábola, Rhodnius prolixus (Hemiptera). La penetración de los ácidos, se realiza a través de la cutícula del abdomen y de los tarsos, se presenta como una acción independiente del grado de distensión de la misma, ya que sus efectos se registran tanto en los insectos repletos, como en los hambrientos; tanto en los tratados tópicamente como en aquellos donde la droga se aplicó al papel de soporte. Los ácidos estudiados aparentemente no afectan la formación de la cutícula, ni la melanización, como tampoco afecta el proceso de la muda. Los daños inducidos por estos ácidos se presentam al azar tanto en los apéndices locomotores como en los cefálicos, observándose un desplazamiento a la proboscide a medida que se incrementa la dosis. De las malformaciones en la proboscide, es el labio el mas dramáticamente dañado, aunque también se presentan daños en los otros apéndices bucales, aisladamente o junto con el daño del labio. El daño en los apéndices locomotores está frecuentemente desplazado al segundo y tercer par de patas, mientras que el par, fue el menos afectado. El ácido octinoico se comportó como teratogénico en las dosis que fueron letales para el insecto con el ácido undecilénico

[The teratogenic and toxic effect of unsaturated short-chain fatty acids in Rhodnius prolixus]. / Efecto teratogénico y toxico de acidos grasos de cadena corta insaturados, en Rhodnius prolixus.

The teratogenic role of two short-chain unsaturated fatty acids, octinoic acid and undecylenic acid on the hemimetabolic metamorphosis of the insect Rhodnius prolixus (Hemipter) is studied. The acids penetrate through the cuticle of the abdomen and tarsi, independently of the amount of distention. The effects are registered equally in satiated or hungry insects, in those treated topically or in those where the treatment was applied to the support paper. The acids apparently do not affect the formation of the cuticle, melanization, nor the metamorphic process. The damage induced by these acids are manifested at random in the locomotor as well as the cephalic appendices, a displacement of the proboscide being observed as the dosage is increased. Octinoic acid acts as a teratogen at doses of undecylenic acid which are lethal for the insect. The malformations of the proboscide include the labium the most dramatically damaged, as well as other bucal appendages, separately or accompanying the damage to the labium. Damage in the locomotor appendages is frequently displaced to the second and third pair of legs, while the first pair is the least affected.