Relationship between microstructure formation and in vitro starch digestibility in baked gluten-starch matrices.

Increased prevalence of diabetes prompts the development of foods with reduced starch digestibility. This study analyzed the impact of adding soluble dietary fiber (inulin-IN; polydextrose-PD) to baked gluten-starch matrices (7.5-13%) on microstructure formation and in vitro starch digestibility. IN and PD enhanced water-holding capacity, the hardness of baked matrices, and lowered water activity in the formulated matrices, potentially explaining the reduced starch gelatinization degree as IN or PD concentration increased. A maximum gelatinization decrease (26%) occurred in formulations with 13% IN. Micro-CT analysis showed a reduction in total and open porosity, which, along with the lower gelatinization degree, may account for the reduced in vitro starch digestibility. Samples with 13% IN exhibited a significantly lower rapidly available glucose fraction (8.56 g/100 g) and higher unavailable glucose fraction (87.76 g/100 g) compared to the control (34.85 g/100 g and 47.59 g/100 g, respectively). These findings suggest the potential for developing healthier, starch-rich baked foods with a reduced glycemic impact.

Analgesic Activity of 5-Acetamido-2-Hydroxy Benzoic Acid Derivatives and an In-Vivo and In-Silico Analysis of Their Target Interactions.

The design, synthesis, and evaluation of novel non-steroidal anti-inflammatory drugs (NSAIDs) with better activity and lower side effects are big challenges today. In this work, two 5-acetamido-2-hydroxy benzoic acid derivatives were proposed, increasing the alkyl position (methyl) in an acetamide moiety, and synthesized, and their structural elucidation was performed using 1H NMR and 13C NMR. The changes in methyl in larger groups such as phenyl and benzyl aim to increase their selectivity over cyclooxygenase 2 (COX-2). These 5-acetamido-2-hydroxy benzoic acid derivatives were prepared using classic methods of acylation reactions with anhydride or acyl chloride. Pharmacokinetics and toxicological properties were predicted using computational tools, and their binding affinity (kcal/mol) with COX-2 receptors (Mus musculus and Homo sapiens) was analyzed using docking studies (PDB ID 4PH9, 5KIR, 1PXX and 5F1A). An in-silico study showed that 5-acetamido-2-hydroxy benzoic acid derivates have a better bioavailability and binding affinity with the COX-2 receptor, and in-vivo anti-nociceptive activity was investigated by means of a writhing test induced by acetic acid and a hot plate. PS3, at doses of 20 and 50 mg/kg, reduced painful activity by 74% and 75%, respectively, when compared to the control group (20 mg/kg). Regarding the anti-nociceptive activity, the benzyl showed reductions in painful activity when compared to acetaminophen and 5-acetamido-2-hydroxy benzoic acid. However, the proposed derivatives are potentially more active than 5-acetamido-2-hydroxy benzoic acid and they support the design of novel and safer derivative candidates. Consequently, more studies need to be conducted to evaluate the different pharmacological actions, the toxicity of possible metabolites that can be generated, and their potential use in inflammation and pain therapy.

The Use of Additives to Prevent Urolithiasis in Lambs Fed Diets with a High Proportion of Concentrate.

This study aimed to evaluate the effectiveness of different additives in preventing urolithiasis in lambs fed a diet rich in concentrate and their impact on performance and blood and urinary parameters. Thirty-two noncastrated male lambs, crossbred Dorper × Santa Inês, with initial body weights (BWs) of 23 ± 0.1 kg and ages of 50 ± 5 days, were kept in individual pens and fed a diet composed of 6% Cynodon ssp. hay and 94% concentrate and subjected to four treatments: CON without inclusion of additives, addition of ACL 5 g/kg of dry matter (DM), addition of CCL 6.3 g/kg of DM, and addition of BZA 5 g/kg of DM. There was no effect of treatment or interaction with time on blood parameters (p > 0.050), and performance characteristics, morphometry of ruminal papillae, and scores of cecum and rumen lesions were not affected by the addition of additives to the diet (p > 0.050). Greater urinary acidification was observed in animals from CCL and ACL treatments (p = 0.033). Calcium chloride acidified the urinary pH and can be used instead of ammonium chloride at a concentration of 0.63% based on DM, when this is the objective.

Benzoic acid complexes with Eudragit E100®: New alternative antimicrobial preservatives.

Given that the use of some preservatives in cosmetics has been restricted, novel alternative preservatives are needed. The aim of this study was to characterize the physicochemical and antimicrobial properties of two polyelectrolyte complexes (EuB100 and EuB75Cl25), which were developed through hot melt extrusion (HME) using benzoic acid (BA) and Eudragit E100. Based on phase diagrams and an experimental statistical design, the solubility of the acid in the polymer and the HME conditions were established. Intermolecular interactions were evaluated through Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRPD). Release behavior was determined for the systems. Antibacterial activity and ζ-potential were determined on Escherichia coli. FTIR revealed acid-base interaction, and XPS showed that the percentages of protonated nitrogen N1s were 13.5% for EuB100 and 20.3% for EuB75Cl25. The BA released showed a non-Fickian behavior, and a satisfactory antibacterial activity against E. coli was demonstrated at pH 6.9. The complexes modified ζ-potential, destabilizing the membrane functionality of E. coli. These complexes are potential antimicrobial preservatives with a greater spectrum of action, with bactericidal activity against E. coli in a wider pH range than uncomplexed BA, even at pH 6.9.

Antifungal Activity of Chemical Constituents from Piper pesaresanum C. DC. and Derivatives against Phytopathogen Fungi of Cocoa.

In this study, the antifungal potential of chemical constituents from Piper pesaresanum and some synthesized derivatives was determined against three phytopathogenic fungi associated with the cocoa crop. The methodology included the phytochemical study on the aerial part of P. pesaresanum, the synthesis of some derivatives and the evaluation of the antifungal activity against the fungi Moniliophthora roreri, Fusarium solani and Phytophthora sp. The chemical study allowed the isolation of three benzoic acid derivatives (1-3), one dihydrochalcone (4) and a mixture of sterols (5-7). Seven derivatives (8-14) were synthesized from the main constituents, of which compounds 9, 10, 12 and 14 are reported for the first time. Benzoic acid derivatives showed strong antifungal activity against M. roreri, of which 11 (3.0 ± 0.8 µM) was the most active compound with an IC50 lower compared with positive control Mancozeb® (4.9 ± 0.4 µM). Dihydrochalcones and acid derivatives were active against F. solani and Phytophthora sp., of which 3 (32.5 ± 3.3 µM) and 4 (26.7 ± 5.3 µM) were the most active compounds, respectively. The preliminary structure-activity relationship allowed us to establish that prenylated chains and the carboxyl group are important in the antifungal activity of benzoic acid derivatives. Likewise, a positive influence of the carbonyl group on the antifungal activity for dihydrochalcones was deduced.

Structural, enzymatic and pharmacological profiles of AplTX-II - A basic sPLA2 (D49) isolated from the Agkistrodon piscivorus leucostoma snake venom.

A basic sPLA2 (D49) from the venom of snake Agkistrodon piscivorus leucostoma (AplTX-II) was isolated, purified and characterized. We determined the enzymatic and pharmacological profiles of this toxin. AplTX-II was isolated with a high level of purity through reverse phase chromatography and molecular exclusion. The enzyme showed pI 9.48 and molecular weight of 14,003 Da. The enzymatic activity of the AplTX-II depended on Ca2+ pH and temperature. The comparison of the primary structure with other sPLA2s revealed that AplTX-II presented all the structural reasons expected for a basic sPLA2s. Additionally, we have resolved its structure with the docked synthetic substrate NOBA (4-nitro-3-octanoyloxy benzoic acid) by homology modeling, and performed MD simulations with explicit solvent. Structural similarities were found between the enzyme's modeled structure and other snake sPLA2 X-Ray structures, available in the PDB database. NOBA and active-site water molecules spontaneously adopted stable positions and established interactions in full agreement with the reaction mechanism, proposed for the physiological substrate, suggesting that NOBA hydrolysis is an excellent model to study phospholipid hydrolysis.

Antifungal Activity of N-(4-Halobenzyl)amides against Candida spp. and Molecular Modeling Studies.

Fungal infections remain a high-incidence worldwide health problem that is aggravated by limited therapeutic options and the emergence of drug-resistant strains. Cinnamic and benzoic acid amides have previously shown bioactivity against different species belonging to the Candida genus. Here, 20 cinnamic and benzoic acid amides were synthesized and tested for inhibition of C. krusei ATCC 14243 and C. parapsilosis ATCC 22019. Five compounds inhibited the Candida strains tested, with compound 16 (MIC = 7.8 µg/mL) producing stronger antifungal activity than fluconazole (MIC = 16 µg/mL) against C. krusei ATCC 14243. It was also tested against eight Candida strains, including five clinical strains resistant to fluconazole, and showed an inhibitory effect against all strains tested (MIC = 85.3-341.3 µg/mL). The MIC value against C. krusei ATCC 6258 was 85.3 mcg/mL, while against C. krusei ATCC 14243, it was 10.9 times smaller. This strain had greater sensitivity to the antifungal action of compound 16. The inhibition of C. krusei ATCC 14243 and C. parapsilosis ATCC 22019 was also achieved by compounds 2, 9, 12, 14 and 15. Computational experiments combining target fishing, molecular docking and molecular dynamics simulations were performed to study the potential mechanism of action of compound 16 against C. krusei. From these, a multi-target mechanism of action is proposed for this compound that involves proteins related to critical cellular processes such as the redox balance, kinases-mediated signaling, protein folding and cell wall synthesis. The modeling results might guide future experiments focusing on the wet-lab investigation of the mechanism of action of this series of compounds, as well as on the optimization of their inhibitory potency.

Antifungal and phytotoxic activity of benzoic acid derivatives from inflorescences of Piper cumanense.

The Piperaceae family is recognized for its diverse biological properties such as antifungal, antibacterial, cytotoxic and insecticidal activities. Phytochemical investigation of inflorescences from P. cumanense led to the isolation and identification of a new 4-chromanone called oxocumanensic acid, along with five known benzoic acid derivatives. The antifungal activity was evaluated against six phytopathogenic fungi by a mycelium growth inhibition test. All compounds were active against the phytopathogenic fungi, showing a greater activity against fungi of Fusarium genus. Finally, phytotoxicity was evaluated in the extract and its chemical constituents, finding that the natural substances are less toxic than the positive control.

Safety assessment of complex benzoic acid using in vitro permeation assays with pig skin in Franz cells / Evaluación de seguridad del ácido benzoico complejado empleando ensayos de permeación in vitro con piel de cerdo en celdas de Franz

SUMMARY Franz cells are one of the main tools to evaluate the transepithelial permeation of compounds through the performance of in vitro tests, these allows inferring the safety behavior of a compound in the skin. The objective of this research was to determine the permeation behavior of benzoic acid from complexes with polyelectrolytes (EuB 75 Cl 25 EuB 100), compared to benzoic acid without complexing, to infer its safety behavior. In a first phase, skin storage conditions were established comparatively evaluating the diffusion parameters (flow and permeation constant) and transepithelial water loss, using ears skin of freshly slaughtered pigs, stored in 1M NaCl at -2 °C for 3 days; it was worked under infinite doses conditions. Subsequently, the permeation test of two complexes between Eudragit E and benzoic acid, in comparison with benzoic acid, was carried out under finite dose conditions. The benzoic acid quantification was performed with an analytical method validated by HPLC-DAD. The results showed no significant differences showing that biological samples can be stored for 72 h under the conditions described. The permeation behavior of the complexed benzoic acid with respect to the free benzoic acid showed a better safety profile, since there was a lower permeation for the first case. These results show that complexation of benzoic acid could decrease the sensitivity reactions that it normally presents, based on the decrease in its permeation.

RESUMEN Las celdas de Franz son una de las herramientas para evaluar la permeación transe-pitelial de compuestos mediante la realización de ensayos in vitro, estos permiten inferir el comportamiento de seguridad de un compuesto en la piel. El objetivo de esta investigación fue determinar el comportamiento de permeación del ácido benzoico a partir de complejos con polielectrolitos (EuB 75 Cl 25 EuB 100) en comparación con el ácido benzoico sin complejar, para inferir su comportamiento de seguridad. En una primera fase, se establecieron las condiciones de almacenamiento de la piel comparando los parámetros de difusión (flujo y constante de permeación) y pérdida de agua transepitelial, empleando piel de orejas de cerdos recién sacrificados, almacenadas en NaCl 1M a -2°C por 3 días; se trabajó bajo condiciones de dosis infinitas. Posteriormente, se realizó el ensayo de permeación de dos complejos entre ácido benzoico y Eudragit E, en comparación con el ácido benzoico, bajo condiciones de dosis finitas. La cuantificación del ácido benzoico fue realizada con un método analítico validado por HPLC-DAD. Los resultados evidenciaron que las muestras biológicas pueden almacenarse durante 72 h en las condiciones descritas. El comportamiento de permeación del ácido benzoico complejado respecto al ácido benzoico libre demostró tener un mejor perfil de seguridad, puesto que hubo una menor permeación para el primer caso. Estos resultados demuestran que la complejación del ácido benzoico podría disminuir las reacciones de sensibilidad que normalmente este presenta, basándose en la disminución de su permeación.

Desarrollo y validación de un método de cromatografía gaseosa para la determinación de mentol, salicilato de metilo, timol y ácido benzoico en solución antiséptica / Development and validation of a gas chromatographic method for the determination of menthol, methyl salicylate, thymol, and benzoic acid in antiseptic solution

RESUMEN Se desarrolló y validó un método por cromatografía gaseosa para la cuantificación simultánea de mentol (MT), salicilato de metilo (SM), timol (TM) y ácido benzoico (AB) en una solución antiséptica bucal. Se utilizó una columna DB-WAX y dietilenglicol como estándar interno. Se determinó la linealidad en un intervalo de concentraciones de 64,00 a 96,00 µg/mL (MT), 80,00 a 120,00 µg/mL (SM), 96,00 a 144,00 µg/mL (TM) y 48,00 a 72,00 µg/mL (AB), obteniendo coeficientes de correlación superiores a 0,999, y coeficientes de variación de los factores de respuestas de 1,18, 1,95, 3,52 y 1,48%, respectivamente. Se establecieron límites de detección de 0,51; 1,14; 3,34 y 1,402 ng/mL para el MT, SM, TM y AB, respectivamente, mientras los límites de cuantificación fueron de 1,45, 3, 43, 9, 73 y 4, 36 ng/mL en cada caso. Los porcentajes de recuperación fueron de 100,03, 99, 31, 99, 92 y 100,12; con coeficientes de variación de 0,42, 0,79, 0,66 y 0,76% para cada caso. El método fue lineal, exacto, preciso y selectivo para la determinación de los analitos en el control de calidad.

SUMMARY A method was developed and validated by gas chromatography for the simultaneous quantification of menthol (MT), methyl salicylate (SM), thymol (TM) and benzoic acid (AB) in an oral antiseptic solution. A DB-WAX column and diethylene glycol was used as internal standard. Linearity was determined in a concentration range of 64.00 to 96.00 µg/mL (MT), 80.00 to 120.00 µg/mL (SM), 96.00 to 144.00 µg/mL (TM) and 48.00 to 72.00 µg/mL (AB) achieving correlation coefficients greater than 0.999, and coefficients of variation of the response factors of 1.18, 1.95, 3.52 and 1.48%, respectively. Detection limits were established: 0.51, 1.14, 3.34 and 1.402 ng/mL for MT, SM, TM, and AB, respectively, while the quantification limits were 1.45, 3.43, 9.73 and 4.36 ng/mL in each case. Recovery percentages were 100.03, 99.31, 99.92 and 100.12; with coefficients of variation of 0.42, 0.79, 0.66 and 0.76% for each case. The method was linear, accurate, precise, and selective for the determination of analytes in quality control.

Novel benzoate-lipophilic cations selectively induce cell death in human colorectal cancer cell lines.

INTRODUCTION: Colorectal cancer (CRC) is a critical health issue worldwide. The high rate of liver and lung metastasis associated with CRC creates a significant barrier to effective and efficient therapy. Tumour cells, including CRC cells, have metabolic alterations, such as high levels of glycolytic activity, increased cell proliferation and invasiveness, and chemo- and radio-resistance. However, the abnormally elevated mitochondrial transmembrane potential of these cells also provides an opportunity to develop drugs that selectively target the mitochondrial functions of tumour cells. METHODS: In this work, we used a new batch of benzoic acid esters with cytotoxic activities attached to the triphenylphosphonium group as a vehicle to target tumour mitochondria and improve their activity. We evaluated the cytotoxicity, selectivity, and mechanism of action of these derivatives, including the effects on energy stress-induced apoptosis and metabolic behaviour in the human CRC cell lines HCT-15 and COLO-205. RESULTS: The benzoic acid derivatives selectively targeted the tumour cells with high potency and efficacy. The derivatives induced the uncoupling of the oxidative phosphorylation system, decreased the transmembrane potential, and reduced ATP levels while increasing AMPK activation, thereby triggering tumour cell apoptosis in both tumour cell lines tested. CONCLUSION: The benzoic acid derivatives studied here are promising candidates for assessing in vivo models of CRC, despite the diverse metabolic characteristics of these tumour cells.

Atividade antimicrobiana de ácidos orgânicos com e sem extrato vegetal no controle in vitro de Escherichia coli e Salmonella Typhi / Antimicrobial activity of organic acids with or without vegetable extracts for in vitro control of Escherichia coli and Salmonella Typhi

Os ácidos orgânicos e alguns extratos herbais podem ser uma alternativa no controle microbiano. Este estudo avaliou a atividade antimicrobiana de uma combinação de ácidos orgânicos com ou sem adição de extratos de Catanea sativa e Acacia decurrens no controle in vitro de Escherichia coli e Salmonella Typhi. Para o estudo, foram utilizadas cepas padrões: Escherichia coli O157:H7 (ATCC 43888) e Salmonella enterica subsp. enterica serovar Typhi (CCCD S003). A combinação de ácidos orgânicos foi composta por 25% de ácido benzoico, 30% de ácido fórmico, 25% de ácido fumárico e 20% de dióxido de sílica. Já a combinação de ácidos orgânicos associada ao extrato vegetal foi composta por 21,2% de ácido benzoico, 25,5% de ácido fórmico, 21,2% de ácido fumárico, 17,1% de dióxido de sílica e 15% de extrato vegetal, sendo este último composto por 50% de castanha portuguesa (Castanea sativa) e 50% de acácia negra (Acacia decurrens). Ambos foram testados em concentrações de 0,00%; 0,40%; 1,70%; 3,20%; 6,25%; 12,50%; 25,00%; 50,00% e 100,00%. O estudo das Concentrações Inibitórias Mínimas (CIM) e Concentrações Bactericidas Mínimas (CBM) das misturas demostraram para Escherichia coli um CIM de 50% e CBM de 100%, tanto para o produto composto pela mistura de ácidos orgânicos quanto para a mistura de ácidos orgânicos com adição do extrato de plantas. Em relação à cepa de Salmonella estudada verificou-se CIM e CBM de 100%, alcançados com 100% de concentração dos compostos estudados. As concentrações de E. coli e Salmonella Typhi expostas a ambos os tratamentos de ácidos orgânicos com ou sem os extratos de plantas diferiram quanto ao tempo de exposição ao produto (p<0,05). A atividade antibacteriana dos produtos depende da concentração empregada dos ácidos orgânicos com ou sem os extratos de plantas e do tempo de exposição aos mesmos.(AU)

Organic acids and some herbal extracts can be an alternative in microbial control. This study evaluated the antimicrobial activity of a combination of organic acids with or without the addition of extracts of Catanea sativa and Acacia decurrens in the in vitro control of Escherichia coli and Salmonella Typhi. For the study, standard strains were used: Escherichia coli O157: H7 (ATCC 43888) and Salmonella enterica subsp. enterica serovar Typhi (CCCD S003). The combination of organic acids was composed of 25% benzoic acid, 30% formic acid, 25% fumaric acid and 20% silica dioxide. The combination of organic acids associated with the plant extract was composed of 21.2% benzoic acid, 25.5% formic acid, 21.2% fumaric acid, 17.1% silica dioxide and 15% extract vegetable, the latter consisting of 50% Portuguese chestnut (Castanea sativa) and 50% black wattle (Acacia decurrens). Both were tested at concentrations of 0.00%; 0.40%; 1.70%; 3.20%; 6.25%; 12.50%; 25.00%; 50.00% and 100.00%. The study of Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) of the mixtures showed for Escherichia coli a MIC of 50% and MBC of 100%, both for the product composed of the mixture of organic acids and for the mixture of organic acids with the addition of plant extract. Regarding the Salmonella strain studied, MIC and MBC of 100% were found, achieved with 100% concentration of the studied compounds. The concentrations of E. coli and Salmonella Typhi exposed to both treatments of organic acids with or without plant extracts differed regarding the time of exposure to the product (p<0.05). The antibacterial activity of the products depends on the concentration of organic acids used with or without plant extracts and the time of exposure to them.(AU)

Atividade antimicrobiana de ácidos orgânicos com e sem extrato vegetal no controle in vitro de Escherichia coli e Salmonella Typhi / Antimicrobial activity of organic acids with or without vegetable extracts for in vitro control of Escherichia coli and Salmonella Typhi

Os ácidos orgânicos e alguns extratos herbais podem ser uma alternativa no controle microbiano. Este estudo avaliou a atividade antimicrobiana de uma combinação de ácidos orgânicos com ou sem adição de extratos de Catanea sativa e Acacia decurrens no controle in vitro de Escherichia coli e Salmonella Typhi. Para o estudo, foram utilizadas cepas padrões: Escherichia coli O157:H7 (ATCC 43888) e Salmonella enterica subsp. enterica serovar Typhi (CCCD S003). A combinação de ácidos orgânicos foi composta por 25% de ácido benzoico, 30% de ácido fórmico, 25% de ácido fumárico e 20% de dióxido de sílica. Já a combinação de ácidos orgânicos associada ao extrato vegetal foi composta por 21,2% de ácido benzoico, 25,5% de ácido fórmico, 21,2% de ácido fumárico, 17,1% de dióxido de sílica e 15% de extrato vegetal, sendo este último composto por 50% de castanha portuguesa (Castanea sativa) e 50% de acácia negra (Acacia decurrens). Ambos foram testados em concentrações de 0,00%; 0,40%; 1,70%; 3,20%; 6,25%; 12,50%; 25,00%; 50,00% e 100,00%. O estudo das Concentrações Inibitórias Mínimas (CIM) e Concentrações Bactericidas Mínimas (CBM) das misturas demostraram para Escherichia coli um CIM de 50% e CBM de 100%, tanto para o produto composto pela mistura de ácidos orgânicos quanto para a mistura de ácidos orgânicos com adição do extrato de plantas. Em relação à cepa de Salmonella estudada verificou-se CIM e CBM de 100%, alcançados com 100% de concentração dos compostos estudados. As concentrações de E. coli e Salmonella Typhi expostas a ambos os tratamentos de ácidos orgânicos com ou sem os extratos de plantas diferiram quanto ao tempo de exposição ao produto (p<0,05). A atividade antibacteriana dos produtos depende da concentração empregada dos ácidos orgânicos com ou sem os extratos de plantas e do tempo de exposição aos mesmos.

Organic acids and some herbal extracts can be an alternative in microbial control. This study evaluated the antimicrobial activity of a combination of organic acids with or without the addition of extracts of Catanea sativa and Acacia decurrens in the in vitro control of Escherichia coli and Salmonella Typhi. For the study, standard strains were used: Escherichia coli O157: H7 (ATCC 43888) and Salmonella enterica subsp. enterica serovar Typhi (CCCD S003). The combination of organic acids was composed of 25% benzoic acid, 30% formic acid, 25% fumaric acid and 20% silica dioxide. The combination of organic acids associated with the plant extract was composed of 21.2% benzoic acid, 25.5% formic acid, 21.2% fumaric acid, 17.1% silica dioxide and 15% extract vegetable, the latter consisting of 50% Portuguese chestnut (Castanea sativa) and 50% black wattle (Acacia decurrens). Both were tested at concentrations of 0.00%; 0.40%; 1.70%; 3.20%; 6.25%; 12.50%; 25.00%; 50.00% and 100.00%. The study of Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) of the mixtures showed for Escherichia coli a MIC of 50% and MBC of 100%, both for the product composed of the mixture of organic acids and for the mixture of organic acids with the addition of plant extract. Regarding the Salmonella strain studied, MIC and MBC of 100% were found, achieved with 100% concentration of the studied compounds. The concentrations of E. coli and Salmonella Typhi exposed to both treatments of organic acids with or without plant extracts differed regarding the time of exposure to the product (p<0.05). The antibacterial activity of the products depends on the concentration of organic acids used with or without plant extracts and the time of exposure to them.

Análisis por FTIR y DSC de complejos polielectrolito entre Eudragit® E100 y ácido benzoico como evidencia de hidrólisis de los grupos éster del polímero / FTIR and DSC analysis of polyelectrolyte complexes between Eudragit® E100 and benzoic acid as evidence of hydrolysis of the polymer ester groups

RESUMEN La obtención de complejos polielectrolito entre el polímero catiónico Eudragit® E100 y moléculas aniónicas, con neutralización adicional de un ácido inorgánico, ha sido una práctica recurrente en el área de investigación de estos sistemas de liberación controlada. En el presente trabajo se buscó estudiar el efecto de la adición del ácido fuerte en el polímero, para ello se llevó a cabo la obtención por evaporación de solvente de diez complejos (de diferente composición entre Eudragit® E100 y ácido benzoico o ácido clorhídrico) y de cuatro ionómeros (sin el activo), a los cuales se les realizó análisis por FTIR y DSC. Los resultados demostraron la obtención de los respectivos complejos polielectro-lito y de los ionómeros; además los espectros de FTIR revelaron la relación directa entre la reacción de hidrólisis de los grupos ésteres del polímero y la proporción de HCl adicionada. Los termogramas, por su parte, evidenciaron la existencia de una reacción en el polielectrolito (PE), la cual se favoreció en aquellas composiciones en las que el proceso de hidrólisis ocurrió en mayor magnitud. El proceso de hidrólisis que se describe en el presente estudio debe tenerse en consideración en las futuras investigaciones en el campo, ya que su ocurrencia podría tener implicaciones en las diversas variables que se evalúan en este tipo de sistemas.

SUMMARY Polyelectrolyte complexes obtention between Eudragit® E100 (cationic polymer) and anionic molecules with additional neutralization of inorganic acids is a common practice in the development of these systems. In the present work the addition of strong acid effect on polymer structure was evaluated through FTIR and DSC analysis of a set of ten complexes with different composition (between Eudragit® E100 and benzoic acid) and four ionomers (without the preservative) obtained by solvent evaporation technique. Results demonstrated the complexes and ionomers formation. FTIR spectra revealed direct relationship between polymer ester groups hydrolysis reaction and the amount of HCl added. The thermograms, on the other hand, evidenced the existence of a reaction in the polyelectrolyte, which was favored in those compositions with more hydrolysis process. The degradation reaction described in this study should be taken into consideration in future research, since its occurrence could have implications in variables evaluated in this type of systems.

Fast and simple method of simultaneous preservative determination in different processed foods by QuEChERS and HPLC-UV: Method development, survey and estimate of daily intake.

A fast and simple method, which employs QuEChERS and HPLC-UV, was developed to determine preservatives in processed foods from different classes. The method showed correlation coefficients above 0.99, LOQs between 0.13 and 0.33 mg kg-1 and recoveries between 91 and 107%, with RSD ≤ 5.3%. Levels of preservatives were up to 2040 mg kg-1 for benzoates, up to 3185 mg kg-1 for sorbates and up to 452 mg kg-1 for methylparaben. Only four out of 82 samples under analysis were above the maximum level allowed by the legislation. Additionally, daily intakes of preservatives were estimated. Regarding benzoates, relatively high intakes were estimated (25% of the acceptable daily intake - ADI) in comparison with sorbates (5% of ADI) and parabens (<1% of ADI), when mean consumption is considered. This method is a good alternative to determining preservatives in different food samples.

Benzoic Acid Derivatives with Trypanocidal Activity: Enzymatic Analysis and Molecular Docking Studies toward Trans-Sialidase.

Chagas, or American trypanosomiasis, remains an important public health problem in developing countries. In the last decade, trans-sialidase has become a pharmacological target for new anti-Chagas drugs. In this work, the aims were to design and find a new series of benzoic acid derivatives as trans-sialidase (TS) inhibitors and anti-trypanosomal agents. Three compounds (14, 18, and 19) sharing a para-aminobenzoic acid moiety showed more potent trypanocidal activity than the commercially available drugs nifurtimox and benznidazole in both strains: the lysis concentration of 50% of the population (LC50) was <0.15 µM on the NINOA strain, and LC50 < 0.22 µM on the INC-5 strain. Additionally, compound 18 showed a moderate inhibition (47%) on the trans-sialidase enzyme and a binding model similar to DANA (pattern A).

Benzoates intakes from non-alcoholic beverages in Brazil, Canada, Mexico and the United States.

Food consumption data from national dietary surveys were combined with brand-specific-use levels reported by beverage manufacturers to calculate the exposure to benzoic acid and its salts (INS Nos 210-213) from non-alcoholic beverages in Brazil, Canada, Mexico and the United States. These four jurisdictions were identified as having some of the most prevalent use of benzoates in beverages globally. Use levels were weighted according to the brand's market volume share in the respective countries. Benzoates were reported to be used primarily in 'water-based flavoured drinks' (Codex General Standard for Food Additives (GSFA) category 14.1.4). As such, the assessments focused only on intakes from these beverage types. Two different models were established to determine exposure: probabilistic (representing non-brand loyal consumers) and distributional (representing brand-loyal consumers). All reported-use levels were incorporated into both models, including those above the Codex interim maximum benzoate use level (250 mg kg-1). The exception to this was in the brand-loyal models for consumers of regular carbonated soft drinks (brand loyal category) which used (1) the interim maximum use level for beverages with a pH ≤ 3.5 and (2) all reported use levels for beverages pH > 3.5 (up to 438 mg kg-1). The estimated exposure levels using both models were significantly lower than the ADI established for benzoates at the mean level of intake (4-40% ADI) and lower than - or at the ADI only for toddlers/children - at the 95th percentile (23-110% ADI). The results rendered in the models do not indicate a safety concern in these jurisdictions, and as such provide support for maintaining the current Codex interim maximum benzoate level of 250 mg kg-1 in water-based beverages.

Phenolic compounds of Brazilian beers from different types and styles and application of chemometrics for modeling antioxidant capacity.

In the present study we aimed at investigating, for the first time, phenolic compounds in Brazilian beers of different types and styles. We also aimed at applying chemometrics for modeling beer's antioxidant capacity as a function of their physicochemical attributes (density, refractive index, bitterness and ethanol content). Samples (n=29) were analyzed by PCA originating five groups, especially according to ethanol contents and bitterness. In general, Group V (alcoholic beers with very high bitterness) presented higher refractive index, bitterness, ethanol and phenolics contents than Groups I (non-alcoholic beers) and II (alcoholic beers with low bitterness). Brazilian beers phenolics profile was distinct from that of European beers, with high contents of gallic acid (0.5-14.7 mg/L) and low contents of ferulic acid (0.2-1.8 mg/L). Using PLS, beer's antioxidant capacity measured by FRAP assay could be predicted with acceptable precision by data of ethanol content and density, bitterness and refractive index values.

Crystal structure of 2-methyl-3-nitro-benzoic anhydride.

The title mol-ecule, C16H12N2O7, lies on a twofold rotation axis which bis-ects the central O atom. The dihedral angle between two symmetry-related benzene rings is 48.54 (9)°. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds which generate C(13) chains running parallel to [31-1].

Electrochemical derivatization-capillary electrophoresis-contactless conductivity detection: a versatile strategy for simultaneous determination of cationic, anionic, and neutral analytes.

The simultaneous determination of cationic, anionic, and neutral analytes in a real sample was demonstrated by coupling electrochemical (EC) derivatization with counter-EOF CE-C(4) D. An EC flow cell was used to oxidize alcohols from an antiseptic mouthwash sample into carboxylic acids at a platinum electrode in acid medium. The carboxylates formed in the derivatization process and other sample ingredients, such as benzoate, saccharinate, and sodium ions, were separated in counter-flow mode and detected in one run in Tris-HCl buffer, pH 8.6. Fewer than 5 min were needed to complete each analysis with the automated flow system comprising solenoid pumps for the management of solutions. Insights into the electrochemistry of benzoic acid, present in the sample matrix, were also gained by EC-CE-C(4) D; more specifically, by applying potentials higher than 1.47 V to the platinum electrode, some formiate and minute amounts of salicylate were detected.