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Abstract A stability-indicating HPLC-DAD method was developed and validated for the simultaneous determination of dasabuvir and its degradation products in the pharmaceutical formulation. The proposed method utilized a Symmetry® C18 (4.6 x 75 mm, 3.5 µm) column, and the mobile phase consisted of an isocratic elution of formic acid (0.1%) and acetonitrile (55:45, v/v), at a flow of 1 mL min-1; analytes were detected at 244 nm. Dasabuvir was submitted to different stress degradation conditions, such as acidic, alkaline, neutral, thermal, oxidative and photolytic, and the structural elucidation of degradation products was performed using LC-QToF-MS/MS. The HPLC-DAD stability-indicating method was validated for selectivity, linearity, limit of detection and quantification, accuracy, precision and robustness, according to ICH guidelines. Dasabuvir produced two degradation products (DP1 and DP2) from the alkaline stress conditions, which were characterized in negative ion mode. Dasabuvir was linear in the range 9.78 to 136.92 µg mL-1, and DP and DP were linear in the range 2.9 to 20.2 µg mL-1 and 1.3 to 14.9 µg mL-1, respectively. The 1 2 recovery ranged between 99.16 and 100.86%, while precision ranged from 1.02 to 2.89%. As the method can effectively separate the dasabuvir from its degradation products and quantitate them, it may be employed as a stability-indicating method for the pharmaceutical formulation.

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Atrazine (ATZ) is a widely used herbicide that has the potential to contaminate the environment and cause deleterious effects on non-target organisms. Release systems for ATZ have been developed to minimize this contamination, such as nanocapsules prepared with poly (ε-caprolactone) (PCL). The objective of this work was to investigate the effects of nanoencapsulated ATZ compared to ATZ on biomarkers of the freshwater teleost Prochilodus lineatus. The fish were exposed for 24 and 96 h to nanoencapsulated ATZ (nATZ) and atrazine (ATZ) at concentrations of 2 and 20 µg L-1, just to the PCL nanocapsules without the herbicide (NANO) in the corresponding amounts or only to dechlorinated water (CTR). The results showed that nATZ was less toxic compared to ATZ, as it did not promote an increase in glycemia, alterations in antioxidants, nor in carbonic anhydrase enzyme activity, and no increase in the frequency of micronuclei and other nuclear erythrocyte abnormalities either. However, exposure to nATZ, as well as to ATZ and PCL nanocapsules, resulted in a reduction in hemoglobin content, increase in erythrocyte DNA damage, as well as changes in Ca2+-ATPase activity, leading to a decrease in plasma Ca+2. The Integrated Biomarker Response Index (IBR) depicted that exposure to ATZ promoted changes in a greater number of biomarkers compared to nATZ, indicating that the nanoencapsulation of the herbicide protected the animal from the effects of ATZ.

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A exposição crônica à radiação solar pode contribuir para o aparecimento do câncer de pele, sendo o uso de fotoprotetores um fator primordial na prevenção desses efeitos deletérios. Atualmente, substâncias bioativas tais como a rutina têm sido foco de interesse da comunidade científica graças às suas propriedades fotoprotetoras e antioxidantes, que podem promover aumento dos valores de FPS, além de conferir características multifuncionais às formulações. Achados in vitro recentes indicam que a rutina, quando incorporada em emulsões fotoprotetoras óleo em água, promove aumento da atividade antioxidante e aumento do FPS. No entanto, a realização de estudos clínicos é fundamental para confirmar e quantificar esses resultados, já que a metodologia in vitro possui baixa repetibilidade e ausência de correlação com ensaios in vivo, principalmente quando as formulações analisadas apresentam substâncias antioxidantes em sua composição. O objetivo deste estudo foi avaliar pela primeira vez a atividade da rutina frente ao FPS e sua segurança clínica através da comparação de formulações fotoprotetoras contendo rutina 0.1% (w/w), avobenzona 3.0% (w/w) e octil dimetil PABA 8.0% (w/w) com uma preparação similar sem o composto bioativo. Adicionalmente, hidratação cutânea, FPS in vitro e atividade antioxidante da rutina em associação com outros filtros foram investigados. O perfil de segurança das formulações qualificou as fórmulas para os testes de eficácia clínica. O teste de DPPH confirmou a capacidade antioxidante da rutina, demonstrando cerca de 40% de aumento na capacidade de sequestro de radicais livres na presença do composto bioativo. A rutina em combinação com os filtros UV aumentou o FPS clínico de 7.30 ± 0.60 para 12.37 ± 1.13, o que representa cerca de 70% de aumento. Os resultados encontrados provam que a rutina em combinação com outros filtros pode aumentar significativamente o valor do FPS e que a mesma é segura para uso clínico

Unprotected chronic exposure to solar radiation can contribute to premature skin cancer and sunscreens are a key factor to avoid those detrimental effects. Currently, there is a growing interest in the photoprotector and antioxidant potential of bioactive substances, such as rutin, that could help to increase the SPF value and add multifunctional characteristics to the formulations. Recent in vitro findings indicated that rutin, when incorporated in oil-in-water photoprotective emulsions can provide antioxidant activity and SPF increase. However, clinical studies are fundamental to determine this activity duo to in vitro methodology lack of repeatability and correlation between the in vivo data, especially when the analyzed formulas contain antioxidant substances. The aim of this study was to evaluate for the first time to date the rutin in vivo SPF and clinical safety by comparing sunscreens formulations containing rutin 0.1% (w/w), butyl methoxydibenzoylmethane 3.0% (w/w) and octyl dimethylPABA 8.0% (w/w) with a similar bioactive-free preparation. Additionally, skin hydration, in vitro SPF and in vitro antioxidant activity of rutin, in association with the UV filters were investigated. The safety profile of the formulations under sun-exposed skin conditions qualified the formulas for clinical efficacy assays. DPPH test confirmed rutin antioxidant properties, demonstrating about 40% increase in radical scavenging potential when the bioactive compound was present. Rutin in combination with the UV filters increased the clinical SPF from 7.30 ± 0.60 to 12.37 ± 1.13, representing about 70% growth in the SPF value. The results obtained proved that rutin in combination with UV filters can improve the SPF value significantly and is safe for clinical use

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ABSTRACT Drug delivery to treat ocular disorders locally is a challenging endeavor. Traditional ocular dosage form - eye drops - exhibits poor availability, consequently inefficient therapeutic response. The objective of the study was to formulate and characterize a ketorolac tromethamine ocular system with a prolonged release pattern based on liposomes as a vesicular carrier and to design once daily liquid preparation realizing the thermal in situ gelation principle. Liposomes were prepared by film hydration method. The influence of cholesterol concentration, pH and volume of hydration medium, and type and concentration of charging imparting agents were studied. Liposomes were characterized via, morphological examination, vesicular size, and encapsulation efficiency, and in vitro release performance, moreover its stability was assessed. The results obtained highlighted that liposomes showed a closed vesicular multi-lamellar structure. Ketorolac was successfully encapsulated within the liposomal structure in a cholesterol and charge inducing agent concentration-dependent behaviour. The dispersion of liposomes within thermosensitive Poloxamer in situ gel was able to retard the release of the drug by diffusion providing a controlled prolonged delivery. The liposomal formulations were physically stable for six months. Ketorolac tromethamine in situ liposomal gel representing an efficient alternative in terms of ocular retention and patient compliance when compared with conventional eye drops.

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A tecnologia da microencapsulação apresenta várias aplicações na indústria de alimentos. Sabendo-se que diferentes fatores intrínsecos e extrínsecos dos alimentos podem influenciar a produção e atividade antimicrobiana das bacteriocinas produzidas pelas bactérias láticas, este estudo teve como principal objetivo avaliar a funcionalidade da encapsulação de bactérias láticas (BAL) bacteriocinogênicas em alginato de cálcio no controle de Listeria monocytogenes em salame experimentalmente contaminado. Para atingir este objetivo, foram isoladas novas cepas de BAL a partir de salame, que foram identificadas e caracterizadas quanto às propriedades das bacteriocinas produzidas, avaliando-se a influência do processo de encapsulação na produção de bacteriocinas. Foram isoladas quatro cepas produtoras de bacteriocinas, identificadas como Lactobacillus sakei (uma cepa), Lactobacillus curvatus (duas cepas) e Lactobacillus plantarum (uma cepa), nomeadas MBSa1, MBSa2, MBSa3 e MBSa4, respectivamente. As bacteriocinas produzidas pelas quatro cepas foram termoestáveis e com exceção da cepa MBSa2, sensíveis a pH acima de 8. Todas inibiram todas as cepas de Listeria monocytogenes testadas e várias espécies de BAL, mas foram inativas contra bactérias Gram negativas. As bacteriocinas foram purificadas por cromatografia de troca iônica seguida de cromatografia de interação hidrofóbica sequencial e cromatografia de fase reversa, observando-se que L. sakei MBSa1 produz um peptídeo de 4303 Da, com uma sequência parcial de aminoacidos idêntica à sequência presente em sakacina A. As cepas MBSa2 e MBSa3 produzem dois peptídeos ativos cada, idênticos nas duas cepas, um de 4457 Da e outro de 4360 Da, que apresentam sequências parciais idênticas às presentes na sakacina P e na sakacina X, respectivamente. Aparentemente, a cepa L. plantarum MBSa4 produz uma bacteriocina composta por duas sub-unidades. O DNA genômico da cepa L. sakei MBSa1 contém os genes da sakacina A e curvacina A, enquanto o DNA da cepa L. plantarum MBSa4 foi positivo para o gene da plantaricina W. A cepa L. curvatus MBSa2 foi encapsulada em alginato de cálcio e testada quanto à produção de bacteriocinas in vitro, observando-se que o processo de encapsulação não influenciou a produção de bacteriocina. Quando testada in situ, ou seja, no salame experimentalmente contaminado com Listeria monocytogenes, não foi observada ação anti-Listeria por L. curvatus MBSa2 encapsulado e não encapsulado, durante o 30 dias de fabricação do salame

The microencapsulation technology has several applications in the food industry. Knowing that different intrinsic and extrinsic factors can influence production and antimicrobial activity of bacteriocins produced by lactic acid bacteria in foods, this study aimed at evaluating the functionality of the encapsulation of bacteriocinogenic lactic acid bacteria (LAB) in calcium alginate in the control of Listeria monocytogenes in experimentally contaminated salami. To achieve this goal, new strains of LAB were isolated from salami, identified and characterized for the properties of the produced bacteriocins, evaluating the influence of the encapsulation process in the bacteriocins production. Four bacteriocin producing strains were isolated and identified as Lactobacillus sakei (one strain), Lactobacillus curvatus (two strains) and Lactobacillus plantarum (one strain), named MBSa1, MBSa2, MBSa3 and MBSa4 respectively. The bacteriocins produced by the four strains were thermostable and with the exception of strain MBSa2, sensitive to pH above 8. All inhibited all tested Listeria monocytogenes strains and various species of LAB but were inactive against Gram-negative bacteria. The bacteriocins were purified by cation-exchange followed by sequential hydrophobic-interaction and reversed-phase chromatography, indicating that L. sakei MBSa1 produces a peptide of 4303 Da, with a partial amino acid sequence identical to the sequence present in sakacin A. L. curvatus MBSa2 and MBSa3 produce two active peptides, identical in the two strains, one of 4457 Da and the other of 4360 Da, with partial aminoacid sequences identical to those present in sakacin X and sakacin P, respectively. Apparently, L. plantarum MBSa4 produces a bacteriocin composed of two subunits. Genomic DNA of L. sakei MBSa1indicated that this strain contains genes for sakacin A and curvacin A, while the DNA of L. plantarum MBSa4 was positive for the plantaricin W gene. The strain L. curvatus MBSa2 was encapsulated in calcium alginate and tested for bacteriocin production in vitro, observing that the encapsulation process did not affect the production of bacteriocin. When tested in situ, i.e. in the salami experimentally contaminated with L. monocytogenes was not observed anti-Listeria action by L. curvatus MBSa2 encapsulated and non-encapsulated during the 30 day manufacture of salami

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Stigmasterol - a plant sterol with several pharmacological activities - is susceptible to oxidation when exposed to air, a process enhanced by heat and humidity. In this context, microencapsulation is a way of preventing oxidation, allowing stigmasterol to be incorporated into various pharmaceutical forms while increasing its absorption. Microparticles were obtained using a blend of polymers of sodium alginate, starch and chitosan as the coating material through a one-stage process using the external gelation technique. Resultant microparticles were spherical, averaging 1.4 mm in size. Encapsulation efficiency was 90.42% and method yield 94.87%. The amount of stigmasterol in the oil recovered from microparticles was 9.97 mg/g. This technique proved feasible for the microencapsulation of stigmasterol.

O estigmasterol, um fitoesterol com diversas atividades farmacológicas, é suscetível à oxidação quando exposto ao ar, calor e umidade. Neste contexto, a microencapsulação é uma forma de proteção contra oxidação, permitindo a incorporação do estigmasterol em diversas formas farmacêuticas e aumentar sua absorção. As micropartículas foram obtidas por gelificação iônica externa, em uma etapa, utilizando como revestimento polímeros naturais de alginato de sódio, amido de milho e quitosana. As micropartículas apresentaram formato esférico com tamanho aproximado de 1,4 mm. O rendimento foi de 94,87% e a eficiência média de encapsulação de 90,42%. A quantidade de estigmasterol no óleo recuperado das micropartículas foi de 9,97 mg/g. O método mostrou-se viável para a microencapsulação do estigmasterol.

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Preparación simple de nuevas N-(6-metil-2-nitrofenil-1,2,3,4-tetrahidroquinolin-4-il) pirrolidin-2-onas y su análisis espectroscópico. Objetivos. Preparar nuevas moléculas N-(1,2,3,4-tetrahidroquinolin-4-il) 2-oxopirrolidínicas y caracterizarlas por métodos espectroscópicos. Materiales y métodos. Todos los reactivos usados son de Aldrich, grado comercial. La pureza de los productos y la composición de las mezclas de reacción fueron monitoreadas por cromatografía en capa fina sobre cromatoplacas de Silufol UV254 (0.25 mm). El aislamiento y purificación se realizó usando cromatografía en columna (SiO2), usando acetato de etilo. Resultados. La preparación de las nuevas N-(tetrahidroquinolin-4-il) pirrolidin-2-onas 4-nitrofenil (ó 2-nitrofenil) sustituidas en C-2 del anillo tetrahidroquinolínico, se realizóvía síntesis one-pot basada en la reacción de cicloadición imino Diels-Alder catalizada por BiCl3 entre toluidina, N-vinilpirrolidin-2-ona y 4-nitrobenzaldehído (3-nitrobenzaldehído). La estructura de los derivados pirrolidónicos fue confirmada por 1H RMN y 13C RMN, además de experimentos 2D RMN y difracción de rayos X de monocristal. Conclusiones. Una ruta eficiente, económica y rápida (reacción imino Diels-Alder multi-componente) fue empleada para la construcción de nuevas moléculas N-(tetrahidroquinolin-4-il) 2-oxopirrolidínicas, esqueleto muy atractivo y usado con estereoquímica bien definida...

Objectives. To prepare new N-(1,2,3,4-tetrahydroquinolin-4-yl) pyrrolidin-2-one molecules and to characterize them by spectroscopic methods. Materials and methods. All reagents were purchased from Aldrich, commercial grade. The purity of the products and the composition of the reaction mixtures were monitored by thin layer chromatography over Silufol UV254 chromatoplates (0.25 mm). Product isolation and purification were performed by column chromatography (SiO2) using ethyl acetate. Results. Preparation of new N-(2-nitrophenyl-1,2,3,4-tetrahydroquinolin-4-yl) pyrrolidin-2-ones has been achieved via the one-pot synthesis, based on a BiCl3-catalyzedimino Diels-Alder cycloaddition reaction of toluidine, N-vinylpyrrolidin-2-one and 4-nitro- or 3-nitrobenzaldehydes. The structure of the pyrrolidine derivatives was confirmed by 1H nmr and 13C nmr studies, in addition to inverse-detected 2D NMR experiments and monocrystal X-ray diffraction. Conclusions. An efficient, economic, and fast synthetic route (multi-component imino Diels-Alder reaction) was employed in the construction of several new tetrahydroquinoline derivatives, useful and attractive rigid skeleton with well-defined stereochemistry...

Preparação simples de novas N-(6-metil-2-nitrofenil-1,2,3,4-tetrahydroquinoline-4-il) pirrolidin-2-onas e sua análise espectroscópica. Objetivos. Preparar novas moléculas N-(1,2,3,4-tetrahydroquinoline-4-il) 2-oxopirrolidínicas e sua caracterização por espectroscopia. Materiais e métodos. Todos os reagentes utilizados são de Aldrich, de grau comercial. A pureza dos produtos e a composição das misturas de reação foram monitoradas por cromatografia em camada fina sobre cromatoplacas de Silufol UV254 (0,25 mm). O isolamento e purificação foi realizado utilizando cromatografia em coluna (SiO2), utilizando acetato de etila. Resultados. Preparação de novas N-(tetrahydroquinoline-4-il) pirrolidin-2-onas 4-nitrofenil (ou 2-nitrofenil) substituídas em C-2 do anel tetrahydroquinoline foi realizada através da síntese “one pot” baseada na reação de cicloadição imino Diels-Alder catalisada por BiCl3 entre toluidina, N-vinilpirrolidin-2-ona e 4 nitrobenzaldehyde (3 nitrobenzaldehyde). A estrutura dos derivados pirrolidónicos foi confirmada por 1H RMN y 13C RMN, experimentos 2D RMN, assim como difração de raios X e monocristais. Conclusões. Uma rota eficiente, econômica e rápida (reação imino Diels-Alder multi-componente) foi utilizada para a construção de novas moléculas N-(tetrahydroquinoline-4-il) 2-oxopirrolidínicas esqueleto muito atraente e usado com estereoquímica bem definida...

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