O pH da região vulvar no ciclo vital: revisão de escopo / The pH of the vulvar region in the life cycle: scoping review / El pH de la región vulvar en el ciclo vital: revisión del alcance

Introdução: mapear os estudos que mensuraram o potencial Hidrogeniônico (pH) da região vulvar no ciclo vital da mulher. Métodos: revisão de escopo conforme recomendações do Manual for Evidence Synthesis do Joanna Briggs Institute (JBI), nas bases SCOPUS, Web of Science, Academic Search Premier, PubMed, Bielefeld Academic Search Engine e Google Acadêmico em janeiro de 2022. Foram incluídos estudos publicados em português, espanhol, francês e inglês, sem limite temporal. Resultados: dos 954 documentos recuperados, 13 foram selecionados. Apurou- se que os estudos utilizaram diferentes procedimentos para as medições quanto aos equipamentos, ambiente e preparo das participantes. A média de idade apresentada pela população feminina estudada variou entre 31 e 43 anos. Os locais de medição vulvar foram os grandes e pequenos lábios, dobra interlabial e períneo. O menor valor do pH aferido foi 4,6 e o maior 6,3. Conclusões: constatou-se baixa produção de estudos acerca do pH vulvar e ênfase das pesquisas na população de mulheres adultas. A diversidade de procedimentos e locais de aferição encontrados não permite afirmações seguras sobre uma faixa de valor de pH da superfície da pele vulvar.

Introduction: to map the studies that measured the Potential of Hydrogen (pH) of the vulvar region in women's life cycle. Methods: scoping review according to recommendations from the Joanna Briggs Institute (JBI) Manual for Evidence Synthesis in the SCOPUS, Web of Science, Academic Search Premier, PubMed, Bielefeld Academic Search Engine and Google Scholar databases in January 2022. Studies published in Portuguese, Spanish, French, and English, without time limit, were included. Results: of the 954 documents retrieved, 13 were selected. Different measurement procedures in relation to equipment, environment and preparation of participants were used in the studies. The average age of the female population ranged between 31 and 43 years. The vulvar measurement sites were the labia majora and minora, interlabial sulci and perineum. The lowest pH value measured was 4.6 and the highest was 6.3. Conclusions: there was a low production of studies on vulvar pH and an emphasis of studies on the population of adult women. The diversity of procedures and measurement sites found does not allow for safe statements about a range of pH values on the surface of the vulvar skin.

Introducción: mapear los estudios que midieron el Potencial de Hidrógeno (pH) de la región vulvar en el ciclo vital de las mujeres. Métodos: revisión del alcance según las recomendaciones del Manual for Evidence Synthesis del Joanna Briggs Institute (JBI), en las bases de datos SCOPUS, Web of Science, Academic Search Premier, PubMed, Bielefeld Academic Search Engine y Google Scholar en enero de 2022. Se incluyeron estudios publicados. en portugués, español, francés e inglés, sin límite de tiempo. Resultados: de los 954 documentos recuperados, se seleccionaron 13. En los estudios se utilizaron diferentes procedimientos de medición en relación con el equipo, el entorno y la preparación de los participantes. La edad media de la población femenina osciló entre 31 y 43 años. Los sitios de medición vulvar fueron los labios mayores y menores, el pliegue interlabial y el perineo. El valor de pH más bajo medido fue 4,6 y el más alto fue 6,3. Conclusiones: hubo una baja producción de estudios sobre pH vulvar y un énfasis de estudios en población de mujeres adultas. La diversidad de procedimientos y sitios de medición encontrados no permite realizar afirmaciones seguras sobre un rango de valores de pH en la superficie de la piel vulvar.

Efeito do pH do gel clareador de consultório na cor e na sensibilidade dentária / Effect of the pHof the in-office tooth bleaching gelon color and tooth sensitivity / Efecto del pH del gel blanqueador dental de consultorio sobre el color y la sensibilidad dental

Introdução:Sabe-se que a busca pela estética é algo cada vez mais crescente. Dentre os procedimentos mais procurados na odontologia estética, destaca-se o clareamento dental de consultório. Diante disso, ainda são poucos os estudos que avaliam os efeitos dos agentes clareadores de diferentes pHs na efetividade clareadora e na sensibilidade dentária.Objetivo:Avaliar a sensibilidade dentária e a eficácia clareadora de géis clareadores à base de peróxido de hidrogênio a 35% com diferentes pHs.Metodologia:Trata-se de um relato de três casos, descritivo e observacional, do tipo boca dividida (split-mouth) para cada estratégia clareadora (gel clareador com pH básico e gel clareador com pH ácido). Foram avaliados três pacientes de25, 26e 27anos de idade.Realizou-se registro de cor por meio da escala VITAClassical e avaliação da sensibilidade dentária pela escala visual analógica. Resultados:Todos os pacientes avaliados apresentaram cor A3 no registro de cor inicial e, após o clareamento dental,atingiram a cor A1. Todos relataram uma maior sensibilidade no hemiarco direito (local onde foi aplicada o gel clareador Whiteness HP que possui pH ácido. Dois pacientes relataram sensibilidade dentária no hemiarco esquerdo em que foi aplicado o gel clareador de pH básico. Conclusões:Observa-se a eficácia clínica dos géis clareadores de consultório à base de peróxido de hidrogênio a 35% na estabilidade de cor após o tratamento clareador, independente do seu pH. Ademais, nota-se que o gel clareador de pH básico promoveu menor sensibilidade pós-operatória (AU).

Introduction:It is known that the search for aesthetics is something increasingly growing. Among the most sought-after procedures in cosmetic dentistry, in-office tooth bleaching stands out. Therefore, there are still few studies that evaluate the effects of bleaching agents ofdifferent pHs on bleaching effectiveness and tooth sensitivity.Objective:To evaluate tooth sensitivity and bleaching efficacy of 35% hydrogen peroxide-based tooth bleaching gels with different pHs.Methodology:This is a report of three cases, descriptive and observational, of the split-mouth type for each bleaching strategy (bleaching gel with basic pH and bleaching gel with acidic pH). Three patients aged 25, 26 and 27 years were evaluated. Color registration was performed using the VITA Classical scale and tooth sensitivity was evaluated using the visual analogue scale.Results:All evaluated patients presented color A3 in the initial color registration and, after tooth bleaching, reached color A1. All reported greater sensitivity in the right hemi-arch (place where the Whiteness HP bleaching gel with an acid pH was applied. Two patients reported tooth sensitivity in the left hemi-arch where the basic pH bleaching gel was applied.Conclusions:The clinical efficacy of in-office tooth bleaching gels based on 35% hydrogen peroxide in terms of color stability after bleaching treatment is observed, regardless of its pH. In addition, it is noted that the basic pH bleaching gel promoted less postoperative sensitivity (AU).

Introducción: Se sabe que la búsqueda de la estética es algo cada vez más creciente. Entre los procedimientos más populares en odontología estética, se destaca el blanqueamiento dental en consultorio. Ante esto, aún existen pocos estudios que evalúen los efectos de agentes blanqueadores de diferentes pHs sobre la efectividad del blanqueamiento y la sensibilidad dental.Objetivo: Evaluar la sensibilidad dental y la eficacia blanqueadora de geles blanqueadores a base de peróxido de hidrógeno al 35 % con diferentes pH. Metodología: Este es un reporte de tres casos, descriptivo y observacional, del tipo boca partida para cada estrategia de blanqueamiento (gel blanqueador con pH básico y gel blanqueador con pH ácido). Se evaluaron tres pacientes de 25, 26 y 27 años. El registro de color se realizó con la escala clásica VITA y la sensibilidad dental se evaluó con la escala analógica visual.Resultados: Todos los pacientes evaluados presentaron color A3 en el registro de color inicial y, después del blanqueamiento dental, alcanzaron el color A1. Todos refirieron mayor sensibilidad en la hemiarcada derecha (lugar donde se aplicó el gel blanqueador de pH ácido Whiteness HP). Dos pacientes refirieron sensibilidad dental en la hemiarcadaizquierda donde se aplicó el gel blanqueador de pH básico.Conclusiones: Se observala eficacia clínica de los geles blanqueadores de consultorio a base de peróxido de hidrógeno al 35% en cuanto a la estabilidad del color tras el tratamiento blanqueador, independientemente de su pH. Además, se observa que el gel blanqueador de pH básico promovió una menor sensibilidad postoperatoria (AU).

Avaliação do potencial erosivo de bebidas ácidas / Evaluation of the erosive potential of acid drinks

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Objetivo: o presente estudo teve como objetivo avaliar, in vitro, o potencial erosivo para o esmalte dentário de bebidas ácidas, comumente ingeridas pela população e encontradas com frequência no comércio da grande Florianópolis, SC, Brasil. Método: a mensuração do potencial erosivo das bebidas foi realizada através da detecção do potencial hidrogeniônico (pH) e acidez titulável (AT). A amostra foi composta por refrigerantes à base de cola, Coca-Cola® e Pepsi®; isotônicos Gatorade®-morango e maracujá e Powerade®-mix de frutas; Chás industrializados Natural Tea®-limão e Chá Matte Leão®-natural; energéticos Red Bull® e Monster Energy®; sucos naturais de Laranja Pera e de Limão Taiti; água saborizada H2OH!®-sabor limão; e água mineral, para o grupo controle. O pH foi aferido com pHmetro digital (Sensoglass SP1800) e para a AT foi utilizado o método padronizado pelo Instituto Adolfo Lutz, todos os ensaios foram realizados em triplicata. Para a análise estatística descritiva, foram empregados teste t e a ANOVA. Resultados: os menores valores de pH foram encontrados para a bebida Coca-Cola® e suco de limão com 2,3. Para AT, as amostras que apresentaram os maiores valores foram os sucos naturais, com 35,1 para o suco de limão e 13,5 para o suco de laranja. Todas as bebidas analisadas possuem potencial erosivo ao esmalte dental, por apresentarem valores de pH menores que 5,5. Quanto as mensurações de AT, os sucos naturais apresentaram os maiores valores. Conclusão: todas as bebidas do estudo foram consideradas iminentemente erosivas à estrutura dental.(AU)

Effect of pH on the chelation between strontium ions and decellularized small intestinal submucosal sponge scaffolds / 北京大学学报(医学版)

OBJECTIVE@#To investigate the preparation of decellularized small intestinal submucosa (dSIS) sponge scaffolds with chelated strontium (Sr) ions at different pH values, and to select the appropriate pH values for synthesizing Sr/dSIS scaffolds using the physicochemical properties and biocompatibility of the scaffolds as evaluation indexes.@*METHODS@#(1) Sr/dSIS scaffolds preparation and grouping: After mixing dSIS solution and strontium chloride solution in equal volumes, adjusting pH of the solution to 3, 5, 7, and 9 respectively, porous scaffolds were prepared by freeze-drying method after full reaction at 37℃, which were named Sr/dSIS-3, -5, -7, and -9 respectively, and the dSIS scaffolds were used as the control group. (2) Physicochemical property evaluation: The bulk morphology of the scaffolds was observed in each group, the microscopic morphology analyzed by scanning electron microscopy, and the porosity and pore size determined, the surface elements analyzed by energy spectroscopy, the structure of functional groups analyzed by infrared spectroscopy, the chelation rate determined by atomic spectrophotometry, the water absorption rate detected by using specific gravity method, and the compression strength evaluated by universal mechanical testing machine.(3) Biocompatibility evaluation: The cytotoxicity and proliferative effect to bone mesenchymal stem cells (BMSCs) of each group were evaluated by Calcein-AM/PI double staining method.@*RESULTS@#Scanning electron microscopy showed that the scaffolds of each group had an interconnected three-dimensional porous structure with no statistical difference in pore size and porosity. Energy spectrum analysis showed that strontium could be detected in Sr/dSIS-5, -7 and -9 groups, and strontium was uniformly distributed in the scaffolds. Functional group analysis further supported the formation of chelates in the Sr/dSIS-5, -7 and -9 groups. Chelation rate analysis showed that the Sr/dSIS-7 group had the highest strontium chelation rate, which was statistically different from the other groups (P < 0.05). The scaffolds in all the groups had good water absorption. The scaffolds in Sr/dSIS-5, -7 and -9 groups showed significantly improved mechanical properties compared with the control group (P < 0.05). The scaffolds in all the groups had good biocompatibility, and the Sr/dSIS-7 group showed the best proliferation of BMSCs.@*CONCLUSION@#When pH was 7, the Sr/dSIS scaffolds showed the highest strontium chelation rate and the best proliferation effect of BMSCs, which was the ideal pH value for the preparation of the Sr/dSIS scaffolds.

Efficient biosynthesis of γ-aminobutyric acid by rationally engineering the catalytic pH range of a glutamate decarboxylase from Lactobacillus plantarum / 生物工程学报

γ-aminobutyric acid can be produced by a one-step enzymatic reaction catalyzed by glutamic acid decarboxylase. The reaction system is simple and environmentally friendly. However, the majority of GAD enzymes catalyze the reaction under acidic pH at a relatively narrow range. Thus, inorganic salts are usually needed to maintain the optimal catalytic environment, which adds additional components to the reaction system. In addition, the pH of solution will gradually rise along with the production of γ-aminobutyric acid, which is not conducive for GAD to function continuously. In this study, we cloned the glutamate decarboxylase LpGAD from a Lactobacillus plantarum capable of efficiently producing γ-aminobutyric acid, and rationally engineered the catalytic pH range of LpGAD based on surface charge. A triple point mutant LpGADS24R/D88R/Y309K was obtained from different combinations of 9 point mutations. The enzyme activity at pH 6.0 was 1.68 times of that of the wild type, suggesting the catalytic pH range of the mutant was widened, and the possible mechanism underpinning this increase was discussed through kinetic simulation. Furthermore, we overexpressed the Lpgad and LpgadS24R/D88R/Y309K genes in Corynebacterium glutamicum E01 and optimized the transformation conditions. An optimized whole cell transformation process was conducted under 40 ℃, cell mass (OD600) 20, 100 g/L l-glutamic acid substrate and 100 μmol/L pyridoxal 5-phosphate. The γ-aminobutyric acid titer of the recombinant strain reached 402.8 g/L in a fed-batch reaction carried out in a 5 L fermenter without adjusting pH, which was 1.63 times higher than that of the control. This study expanded the catalytic pH range of and increased the enzyme activity of LpGAD. The improved production efficiency of γ-aminobutyric acid may facilitate its large-scale production.

Expression and characterization of mesophilic GH1 β-glucosidase CdBglA from acidophilic Cuniculiplasma divulgatum / 生物工程学报

β-glucosidase has important applications in food, pharmaceutics, biomass conversion and other fields, exploring β-glucosidase with strong adaptability and excellent properties thus has received extensive interest. In this study, a novel glucosidase from the GH1 family derived from Cuniculiplasma divulgatum was cloned, expressed, and characterized, aiming to find a better β-glucosidase. The amino acid sequences of GH1 family glucosidase derived from C. divulgatum were obtained from the NCBI database, and a recombinant plasmid pET-30a(+)-CdBglA was constructed. The recombinant protein was induced to express in Escherichia coli BL21(DE3). The enzymatic properties of the purified CdBglA were studied. The molecular weight of the recombinant CdBglA was 56.0 kDa. The optimum pH and temperature were 5.5 and 55 ℃, respectively. The enzyme showed good pH stability, 92.33% of the initial activity could be retained when treated under pH 5.5-11.0 for 1 h. When pNPG was used as a substrate, the kinetic parameters Km, Vmax and Kcat/Km were 0.81 mmol, 291.99 μmol/(mg·min), and 387.50 s-1 mmol-1, respectively. 90.33% of the initial enzyme activity could be retained when CdBglA was placed with various heavy metal ions at a final concentration of 5 mmol/L. The enzyme activity was increased by 28.67% under 15% ethanol solution, remained unchanged under 20% ethanol, and 43.68% of the enzyme activity could still be retained under 30% ethanol. The enzyme has an obvious activation effect at 0-1.5 mol/L NaCl and can tolerate 0.8 mol/L glucose. In conclusion, CdBglA is an acidic and mesophilic enzyme with broad pH stability and strong tolerance to most metal ions, organic solvents, NaCl and glucose. These characteristics may facilitate future theoretical research and industrial production.

Expression of β-xylosidase An-xyl from Aspergillus niger and characterization of its xylose tolerance / 生物工程学报

The hydrolysis of xylo-oligosaccharides catalyzed by β-xylosidase plays an important role in the degradation of lignocellulose. However, the enzyme is easily inhibited by its catalytic product xylose, which severely limits its application. Based on molecular docking, this paper studied the xylose affinity of Aspergillus niger β-xylosidase An-xyl, which was significantly differentially expressed in the fermentation medium of tea stalks, through cloning, expression and characterization. The synergistic degradation effect of this enzyme and cellulase on lignocellulose in tea stems was investigated. Molecular docking showed that the affinity of An-xyl to xylose was lower than that of Aspergillus oryzae β-xylosidase with poor xylose tolerance. The Ki value of xylose inhibition constant of recombinant-expressed An-xyl was 433.2 mmol/L, higher than that of most β-xylosidases of the GH3 family. The Km and Vmax towards pNPX were 3.6 mmol/L and 10 000 μmol/(min·mL), respectively. The optimum temperature of An-xyl was 65 ℃, the optimum pH was 4.0, 61% of the An-xyl activity could be retained upon treatment at 65 ℃ for 300 min, and 80% of the An-xyl activity could be retained upon treatment at pH 2.0-8.0 for 24 h. The hydrolysis of tea stem by An-xyl and cellulase produced 19.3% and 38.6% higher reducing sugar content at 2 h and 4 h, respectively, than that of using cellulase alone. This study showed that the An-xyl mined from differential expression exhibited high xylose tolerance and higher catalytic activity and stability, and could hydrolyze tea stem lignocellulose synergistically, which enriched the resource of β-xylosidase with high xylose tolerance, thus may facilitate the advanced experimental research and its application.

Regulation of pH on inflation and deflation of biosynthetic gas vesicles used as ultrasound molecular imaging probes / 生物工程学报

Gas vesicles (GVs) are gas-filled protein nanostructures that can regulate the buoyancy of microorganisms such as cyanobacteria and archaea. Recent studies have shown that GVs have the potential to be used as ultrasound molecular imaging probes in disease diagnosis and treatment. However, the mechanism of the inflation and deflation of GVs remains unclear, which hampers the preservation of GVs and gas replacement. In the present study, the environmental pH value was found to be an important factor in regulating the inflation and deflation of GVs. It can not only regulate the inflation and deflation of GVs in vivo to make Microcystis sp. cells present distinct levitation state, but also regulate the inflation and deflation of purified GVs in vitro, and the regulation process is reversible. Our results may provide a technical support for the large-scale production and preservation of biosynthetic ultrasound molecular imaging probes, especially for gas replacement to meet different diagnostic and therapeutic needs, and would facilitate the application of biosynthetic ultrasound molecular imaging probes.

Rational design of L-arabinose isomerase from Lactobacillus fermentum and its application in D-tagatose production / 生物工程学报

L-arabinose isomerase (L-AI) is the key enzyme that isomerizes D-galactose to D-tagatose. In this study, to improve the activity of L-arabinose isomerase on D-galactose and its conversion rate in biotransformation, an L-arabinose isomerase from Lactobacillus fermentum CGMCC2921 was recombinantly expressed and applied in biotransformation. Moreover, its substrate binding pocket was rationally designed to improve the affinity and catalytic activity on D-galactose. We show that the conversion of D-galactose by variant F279I was increased 1.4 times that of the wild-type enzyme. The Km and kcat values of the double mutant M185A/F279I obtained by superimposed mutation were 530.8 mmol/L and 19.9 s-1, respectively, and the catalytic efficiency was increased 8.2 times that of the wild type. When 400 g/L lactose was used as the substrate, the conversion rate of M185A/F279I reached a high level of 22.8%, which shows great application potential for the enzymatic production of tagatose from lactose.

Modulating the production of xylanase by Bacillus pumilus BS131 through optimization using waste fiber sludge / Modulando a produção de xilanase por Bacillus pumilus BS131 por meio da otimização usando lodo de fibra residual

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.

Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.

Light-curing of calcium hydroxide-based liners: pH analysis and calcium ion release / Fotoativação de forradores a base de hidróxido de cálcio: análise de pH e liberação de íons cálcio

Objective: Compare the pH values and calcium ion release of calcium hydroxide-based liner materials before and after light-curing. Material and Methods: The materials evaluated were: hydrox-cal white (HW), hydrox-cal dentin (HD), Biocal (BC) and UltraBlend Plus (UB). 120 samples of the liner materials were inserted into a PVC tube (n=15). The samples from HW+A, HD+A, BC+A and UB+A were subjected to photoactivation. The other groups HW+N, HD+N, BC+N and UB+N were only inserted in a glass tube with deionized water. The pH was measured 24 hours and 14 days after the inclusion of the samples with the aid of a pH meter. The calcium release was analyzed with the aid of an atomic absorption spectophotometer at 24h and 14 days. The results were submitted to the Shapiro-Wilk test, followed by ANOVA and Tukey test (p=0.05). Results: In 24h, the groups that were not light cured showed the highest pH values (p<0.05). In 14 days, BC+N and BC+A demonstrated the lowest pH values. The groups that were not light cured also showed higher calcium release values in 24h and 14 days (p<0.05). Conclusion: Photoactivation of calcium hydroxide-based liner materials negatively interferes with calcium ion release, as well as with pH.(AU)

Objetivo: Comparar os valores de pH e liberação de íons cálcio de materiais forradores à base de hidróxido de cálcio antes e depois da fotopolimerização. Material e métodos: Os materiais avaliados foram: Hidrox-cal branco (HW), Hidrox-cal dentina (HD), Biocal (BC) e UltraBlend Plus (UB). 120 amostras dos materiais de revestimento foram inseridas em um tubo de PVC (n=15). As amostras de HW +A, HD+A, BC+A e UB+A foram submetidas à fotoativação. Os demais grupos HW +N, HD+N, BC+N e UB+N foram inseridos apenas em um tubo de vidro com água deionizada. O pH foi medido 24 horas e 14 dias após a inclusão das amostras com o auxílio de um medidor de pH. A liberação de cálcio foi analisada com o auxílio de um espectrofotômetro de absorção atômica em 24h e 14 dias. Os resultados foram submetidos ao teste de Shapiro-Wilk, seguido de ANOVA e teste de Tukey (p=0,05). Resultados: Em 24h, os grupos não fotopolimerizados apresentaram os maiores valores de pH (p<0,05). Em 14 dias, BC+N e BC+A apresentaram os menores valores de pH. Os grupos não fotopolimerizados também apresentaram maiores valores de liberação de cálcio em 24h e 14 dias (p<0,05). Conclusão: A fotoativação de materiais de revestimento à base de hidróxido de cálcio interfere negativamente na liberação de íons cálcio e no pH (AU)

Chromatographic study of sitagliptin and ertugliflozin under quality-by-design paradigm

Abstract The present study entails the systematic development and validation of a stability-indicating RP-HPLC method for the analysis of sitagliptin and ertugliflozin in a fixed-dose combination. Analytical quality by design (AQbD) concepts were used to define critical method variables, employing Pareto risk assessment and a Placket-Burman screening design, preceded by a Box-Behnken design with response surface analysis to optimise critical method parameters such as % acetonitrile (X1), buffer pH (X2) and column oven temperature (X3). Multiple response optimisation (Derringer's desirability) of variables was accomplished by studying critical analytical attributes, such as resolution, retention time and theoretical plates. The title analytes were separated effectively on a PRONTOSIL C18 column at 37 °C using a mobile phase of acetonitrile:acetate buffer, pH 4.4 (36:64 percent v/v), pumped at a flow rate of 1 mL/min, and UV detection at 225 nm. Linearity was observed over a concentration range of 25-150 µg/mL and 3.75-22.5 µg/mL at retention times of 2.82 and 3.92 min for sitagliptin and ertugliflozin, respectively. The method obeyed all validation parameters of the ICH Q2(R1) guidelines. The proposed robust method allows the study of the selected drugs in pharmaceutical dosage forms as well as in drug stability studies under various stress conditions.

Erosive potential associated with the pH of industrialized and natural drinks

Nowadays there is an increase in the consumption of acidic drinks, especially the fermented ones. Its ingestion is closely associated with the demineralization of superficial dental tissues, which characterizes dental erosion. The objective of this study was to evaluate the pH of industrialized and natural drinks. The sample consisted of soft drinks, natural and artificial juices, fermented drinks, isotonic drinks and energy from different commercial brands acquired in the city of Niterói (RJ). The products were kept at room temperature (25oC) for 1 hour and were aliquoted 3 mL of each drink to a Becker to measure pH in a specific electrode coupled to a potentiometer. The readings were performed in triplicate. The mean pH ranged from 2.34 to 4.31, the most acidic drink was the refrigerant and the less acidic, the curd. It was found that all drinks analyzed had an acidic pH. Thus, potentially erosive dental structures.

Atualmente, há um aumento no consumo de bebidas ácidas, especialmente as fermentadas. Sua ingestão está intimamente associada à desmineralização dos tecidos dentários superficiais, o que caracteriza a erosão dentária. O objetivo da presente pesquisa foi avaliar o potencial erosivo de bebidas industrializadas e naturais. A amostra de conveniência foi constituída de refrigerantes, sucos naturais e artificiais, bebidas fermentadas, isotônicos e energéticos de diferentes marcas comerciais adquiridas no município de Niterói (RJ). Os produtos foram mantidos em temperatura ambiente (25oC) durante 1 hora e foram aliquotados 3 mL de cada bebida para um Becker para a mensuração de pH em eletrodo específico acoplado a um potenciômetro. As leituras foram realizadas em triplicata. Os valores médios de pH variaram de 2,34 a 4,31, sendo a bebida mais ácida um refrigerante e a menos ácida, a coalhada. Constatou-se que todas as bebidas analisadas apresentaram um pH ácido e abaixo do crítico para a dissolução do esmalte, sendo estas potencialmente erosivas das estruturas dentárias.

Cyperus esculentus L. protects testis and sperm morphology of hyperglycaemic rats / Cyperus esculentus L. protege la morfología de los testículos y los espermatozoides de ratas hiperglicémicas

Cyperus esculentus L. (tiger nut) is a tuberous plant that promotes and protects reproductive functions, which are usually hampered in diabetics. The present study investigated the effect of Cyperus esculentus tuber extract (CETE) on testicular histology and sperm viability of alloxan-induced hyperglycaemic Wistar rats. Twenty-five adult male Wistar rats weighing 150-200g and grouped into five (n=5): Group 1, the control, administered tap water (20mL/kg), while groups 2-5 were administered a single intraperitoneal dose (120mg/kg b.w.) of alloxan, and each further received orally tap water (20mL/kg), CETE (100mg/kg), CETE (500 mg/kg) and metformin (500 mg/kg), respectively for 21 days. The animals were sacrificed, their sperm collected for analysis, while the testes were harvested, and processed for histology. Results showed significantly increased (p<0.05) blood glucose and testosterone, and significantly decreased (p<0.05) sperm pH, motility, count, morphology and density, as well as disruptions and hypertrophy of the spermatogenic and Sertoli cells of the hyperglycaemic group. There were significant (p<0.05) blood glucose decline, while the sperm parameters and testicular weight improved with normal testicular histology in the 100 mg/kg CETE, 500 mg/kg CETE, and metformin-treated groups compared to the control and hyperglycaemic group. Treatment with CETE showed blood glucose amelioration and improved sperm quality, as well as testicular damage attenuation.

Cyperus esculentus L. es una planta tuberosa que promueve y protege las funciones reproductivas, que generalmente se ven afectadas en los diabéticos. El presente estudio investigó el efecto del extracto de tubérculo de Cyperus esculentus (CETE) sobre la histología testicular y la viabilidad de los espermatozoides de ratas wistar con hiperglicemia inducida por alloxan. Veinticinco ratas Wistar macho adultas que pesaban 150-200 g y se agruparon en cinco (n = 5): el grupo 1, el control, administró agua del grifo (20ml / kg), mientras que los grupos 2-5 se les administró una dosis intraperitoneal única (120 mg / kg p.v.) de alloxan, y agua del grifo por vía oral (20ml/kg), CETE (100 mg/kg), CETE (500 mg/kg) y metformina (500 mg/kg), respectivamente durante 21 días. Los animales fueron sacrificados, su esperma recolectada para su análisis, mientras que los testículos fueron retirados y procesados para histología. Los resultados mostraron un aumento significativo (p<0,05) de la glucosa en sangre y la testosterona, y una disminución significativa (p<0,05) del pH, la motilidad, el recuento, la morfología y la densidad de los espermatozoides, así como interrupciones e hipertrofia de las células espermatogénicas y sertoli del grupo hiperglucémico. Hubo una disminución significativa (p<0,05) de la glucosa en sangre, mientras que los parámetros espermáticos y el peso testicular mejoraron con la histología testicular normal en los grupos de 100 mg / kg de CETE, 500 mg / kg de CETE y tratados con metformina en comparación con el grupo de control e hiperglucémico. El tratamiento con CETE mostró una mejora de la glucosa en sangre y una mejora de la calidad de los espermatozoides, así como atenuación del daño testicular.

Anti-inflammatory effects and acute oral toxicity of Copaifera spp. essential oil-loaded nanoemulsion / Efectos antiinflamatorios y toxicidad oral aguda de nanoemulsión cargada de aceite esencial de Copaifera spp

Copaifera spp. essential oil (EOC) was extracted by hydrodistillation of Copaifera oleoresin (COR). The EOC was characterized by GC/MS and a novel EOC-loaded nanoemulsion was developed to enhance the EOC solubility and to evaluate its utility as antinflammatory. EOC contain 14 volatile compounds (including ß-caryophyllene: 51.52%) having a required HLB of 11. The Surfactant: EOC: Water ratio of 13:15:75 (%, w:w:w) produced the optimal formulation (particle size: 94.47 nm). The EOC-loaded nanoemulsion presented a pseudoplastic/thixotropic behavior with excellent shelf stability for 6 months. The anti-inflammatory effect of the nanoemulsion was more potent than that of the EOC, and statistically equal to diclofenac (50 mg/kg). The EOC-loaded nanoemulsion showed no oral acute toxicity (in mice) at 2000 mg/kg; hence, it is considered a nontoxic product. The development of the EOC-loaded nanoemulsion added value to both the COR and the EOC by providinga suitable formulation that could be used as an anti-inflammatory product.

El aceite esencial (EOC) fue extraído por hidrodestilación de oleoresina de Copaifera spp. El EOC fue caracterizado químicamente por GC/MS. Se formuló una nanoemulsión con EOC para mejorar la solubilidad del EOC y evaluar su utilidad como antiinflamatorio. El EOC contiene 14 compuestos volátiles (incluido el ß-cariofileno: 51,52%) con un HLB requerido de 11. La relación Tensioactivo: EOC: Agua de 13:15:75 (%, p:p:p) produjo la formulación óptima (tamaño de partícula: 94,47 nm).. La nanoemulsión cargada con EOC presentó un comportamiento pseudoplástico/tixotrópico con una excelente estabilidad en almacenamiento durante 6 meses. El efecto antiinflamatorio de la nanoemulsión fue más potente que el del EOC y estadísticamente igual al diclofenaco (50 mg/kg). La nanoemulsión cargada con COE no mostró toxicidad aguda oral (en ratones) a 2000 mg/kg; por lo tanto, se considera un producto no tóxico. El desarrollo de la nanoemulsión cargada con EOC agregó valor tanto al COR como al EOC al proporcionar una formulación adecuada que podría usarse como un producto antiinflamatorio.

Fórmula artesanal a base de lactosuero: complemento alimenticio para niños preescolares / Artisanal whey-based formula: food supplement for preschool children

Resumen Se pretendió desarrollar una fórmula artesanal, a base de lactosuero, como complemento alimenticio para niños preescolares. Se realizó una investigación descriptiva ejecutada en tres fases: 1. Ensayos preliminares para la determinación del esquema tecnológico; 2. Evaluación fisicoquímica para la caracterización del producto y determinación de macronutrientes y 3. Evaluación sensorial donde se midió el nivel de agrado del producto final. Los datos obtenidos de los análisis se tabularon en cuatro repeticiones y se analizaron a través de estadísticas descriptivas de tendencia central y en frecuencias expresadas en tablas y gráficos mediante el programa estadístico SPSS versión 20.0. Se obtuvo que en el análisis proximal del requesón deshidratado, éste aportó por cada 100 gramos de producto: 480,28 kcal, 46,5% de proteínas, 22,36% de grasas y 23,26% de hidratos de carbono. La formulación final de la bebida constó de 2,9 g de requesón deshidratado, 3,6 g de arroz previamente cocido y 1,8 g de azúcar diluidos por cada onza preparada. Se determinó que es una fórmula hipocalórica-hiperproteica e isoosmolar, con una viscosidad de 275cP, un pH de 5,1 y con 0,291% de ácido láctico. La fórmula artesanal a base de lactosuero fue de agrado para 41 niños que participaron en el análisis sensorial. Se recomienda su uso en niños que se encuentren en condición de vulnerabilidad nutricional.

Abstract The main objective of this research was to develop an artisan formula based on whey as food supplement directed to preschool children. It was a descriptive study carried out in three phases: 1. Preliminary tests, for the determination of the technological scheme; 2. Physical-chemical evaluation, for the characterisation of the product and determination of nutrients and, 3. Sensory evaluation: the level of satisfaction of the final product measured. The data obtained from the analysis were tabulated in four repetitions and analysed through descriptive statistics of central tendency and in frequencies expressed in tables and graphs using the statistical program SPSS version 20.0. As a result, for each 100 grams of dehydrated cottage cheese this malnuprovides: 480.28 kcal, 46.5% protein; 22.36% fat and 23.26% carbohydrates. The final formulation of the drink consisted of 2.9 g of dehydrated cottage cheese, 3.6 g of previously cooked rice and 1.8 g of diluted sugar for each prepared ounce. It was determined as a hypocaloric-hyperproteic and isomolar formula, with a viscosity of 275cP, a pH of 5.1 and with 0.291% lactic acid. The artisan formula based on whey was liked by 41 children who participated in the sensory analysis. As a conclusion, it can be recommended as food supplement in children with nutritional vulnerability conditions.

Resumo O objetivo principal desta pesquisa foi desenvolver uma fórmula artesanal à base de soro de leite como suplemento alimentar direcionado a crianças pré-escolares. Foi realizado um estudo descritivo em três fases: 1. Ensaios preliminares, para determinação do esquema tecnológico; 2. Avaliação físico-química, para caracterização do produto e determinação de macronutrientes e 3. Avaliação sensorial: mediu-se o grau de satisfação do produto final. Os dados obtidos das análises foram tabulados em quatro repetições e analisados por meio de estatísticas descritivas de tendência central e em frequências expressas em tabelas e gráficos utilizando o programa estatístico SPSS versão 20.0. Como resultado da análise proximal, para cada 100 gramas de requeijão desidratado fornece: 480,28 kcal, 46,5% de proteína; 22,36% de gordura e 23,26% de carboidratos. A formulação final da bebida consistiu em 2,9 g de requeijão desidratado, 3,6 g de arroz previamente cozido e 1,8 g de açúcar diluído para cada onça preparada. O resultado concluiu que é uma fórmula hipocalórica-hiperproteica e isoosmolar, com viscosidade de 275cP, pH de 5,1 e com 0,291% de ácido lático. A fórmula artesanal à base de soro de leite foi apreciada por 41 crianças que participaram da análise sensorial. É recomendado seu uso em crianças que se encontrem em condições de vulnerabilidade nutricional.

Obtainment and characterization of digestive aspartic proteases from the fish Caranx hippos (Linnaeus, 1766) / Obtenção e caracterização de proteases aspárticas digestórias do peixe Caranx hippos (Linnaeus, 1766)

This work aimed to obtain aspartic proteases of industrial and biotechnological interest from the stomach of the crevalle jack fish (Caranx hippos). In order to do so, a crude extract (CE) of the stomach was obtained and subjected to a partial purification by salting-out, which resulted in the enzyme extract (EE) obtainment. EE proteases were characterized physicochemically and by means of zymogram. In addition, the effect of chemical agents on their activity was also assessed. By means of salting-out it was possible to obtain a purification of 1.6 times with a yield of 49.4%. Two acid proteases present in the EE were observed in zymogram. The optimum temperature and thermal stability for EE acidic proteases were 55 ºC and 45 °C, respectively. The optimum pH and pH stability found for these enzymes were pH 1.5 and 7.0, respectively. Total inhibition of EE acid proteolytic activity was observed in the presence of pepstatin A. dithiothreitol (DTT) and Ca2+ did not promote a significant effect on enzyme activity. In the presence of heavy metals, such as Al3+, Cd2+ and Hg2+, EE acidic proteases showed more than 70% of their enzymatic activity. The results show that it is possible to obtain, from the stomach of C. hippos, aspartic proteases with high proteolytic activity and characteristics that demonstrate potential for industrial and biotechnological applications.

Este trabalho objetivou obter proteases aspárticas de interesse industrial e biotecnológico a partir do estômago do peixe xaréu (Caranx hippos). Para isso, foi obtido um extrato bruto do estômago, o qual foi submetido a uma purificação parcial por salting-out onde se obteve o extrato enzimático (EE). As proteases do EE foram caracterizadas físico-quimicamente e através de zimograma. Além disso, o efeito de agentes químicos sobre sua atividade também foi avaliado. Através de salting-out foi possível obter uma purificação de 1,6 vezes com rendimento de 49,4%. Foram observadas duas proteases ácidas presentes no EE através de zimograma. A temperatura ótima e a estabilidade térmica para as proteases ácidas do EE foram de 55 ºC e 45 °C, respectivamente. O pH ótimo e a estabilidade ao pH encontrados para estas enzimas foram o pH 1,5 e 7,0, respectivamente. Observou-se a inibição total da atividade proteolítica ácida do EE na presença de pepstatina A. O ditiotreitol (DTT) e o Ca2+ não promoveram efeito significativo na atividade enzimática. Na presença de metais pesados, como Al3+, Cd2+ e Hg2+, o EE manteve mais de 70% de atividade enzimática do EE. Os resultados mostram que é possível obter, a partir do estômago de C. hippos, proteases aspárticas com alta atividade proteolítica e características que demonstram potencial para aplicações industriais e biotecnológicas.

Expression and characterization of a bifunctional thermal β-glucosidase IuBgl3 from thermophilic archaeon Infirmifilum uzonense / 生物工程学报

β-glucosidase has important applications in food, medicine, biomass conversion and other fields. Therefore, exploring β-glucosidase with strong stability and excellent properties is a research hotspot. In this study, a GH3 family β-glucosidase gene named Iubgl3 was successfully cloned from Infirmifilum uzonense. Sequence analysis showed that the full length of Iubgl3 was 2 106 bp, encoding 702 amino acids, with a theoretical molecular weight of 77.0 kDa. The gene was cloned and expressed in E. coli and the enzymatic properties of purified IuBgl3 were studied. The results showed that the optimal pH and temperature for pNPG hydrolysis were 5.0 and 85 ℃, respectively. The enzyme has good thermal stability, and more than 85% of enzyme activity can be retained after being treated at 80 ℃ for2 h. This enzyme has good pH stability and more than 85% of its activity can be retained after being treated at pH 4.0-11.0 for 1 h. It was found that the enzyme had high hydrolysis ability to p-nitrophenyl β-d-glucoside (pNPG) and p-nitrophenyl β-d-xylopyranoside (pNPX). When pNPG was used as the substrate, the kinetic parameters Km and Vmax were 0.38 mmol and 248.55 μmol/(mg·min), respectively, and the catalytic efficiency kcat/Km was 6 149.20 s-1mmol-1. Most metal ions had no significant effect on the enzyme activity of IuBgl3. SDS completely inactivated the enzyme, while EDTA increased the enzyme activity by 30%. This study expanded the β-glucosidase gene diversity of the thermophilic archaea GH3 family and obtained a thermostable acid bifunctional enzyme with good industrial application potential.

Carangoides bartholomaei (Cuvier, 1833) stomach: a source of aspartic proteases for industrial and biotechnological applications / Estômago de Carangoides bartholomaei (Cuvier, 1833): uma fonte de proteases aspárticas para aplicações industriais e biotecnológicas

The viscera and other residues from fish processing are commonly discarded by the fishing industry. These byproducts can be a source of digestive enzymes with industrial and biotechnological potential. In this study, we aimed at the extraction, characterization, and application of acidic proteases from the stomach of Carangoides bartholomaei (Cuvier, 1833). A crude extract from the stomachs was obtained and submitted to a partial purification process by salting-out, which obtained a Purified Extract (PE) with a specific proteolytic activity of 54.0 U·mg-1. A purification of 1.9 fold and a yield of 41% were obtained. The PE presents two isoforms of acidic proteases and a maximum proteolytic activity at 45 °C and pH 2.0. The PE acidic proteolytic activity was stable in the pH range of 1.5 to 7.0 and temperature from 25 °C to 50 °C. Purified Extract kept 35% of its proteolytic activity at the presence of NaCl 15% (m/v) but was totally inhibited by pepstatin A. Purified Extract aspartic proteases presented high activity in the presence of heavy metals such as Cd2+, Hg2+, Pb2+, Al3+, and Cu2+. The utilization of PE as an enzymatic addictive in the collagen extraction from Nile tilapia scales has doubled the process yield. The results indicate the potential of these aspartic proteases for industrial and biotechnological applications.

As vísceras e outros resíduos do processamento de peixes são geralmente descartados pela indústria pesqueira. Esses resíduos podem ser uma fonte de enzimas digestivas com potencial industrial e biotecnológico. Neste estudo, objetivamos a extração, caracterização e aplicação de proteases aspárticas do estômago de Carangoides bartholomaei (Cuvier, 1833). Um extrato bruto do estômago foi obtido e submetido a um processo de purificação parcial, que obteve um Extrato Purificado (EP) com uma atividade proteolítica específica de 54,0 U·mg-1. Foi obtida uma purificação de 1,9 vezes e um rendimento de 41%. O EP apresenta duas isoformas de proteases ácidas e atividade proteolítica máxima a 45 °C e pH 2,0. A atividade proteolítica do EP foi estável na faixa de pH de 1,5 a 7,0 e temperatura de 25 °C a 50 °C. O EP manteve 35% de sua atividade proteolítica na presença de NaCl a 15% (m/v), mas foi totalmente inibida pela pepstatina A. As proteases ácidas do EP apresentaram alta atividade na presença de metais pesados como o Cd2+, Hg2+, Pb2+, Al3+ e Cu2+. A utilização de EP como aditivo enzimático na extração de colágeno a partir de escamas de tilápia do Nilo dobrou o rendimento do processo. Os resultados indicam um potencial dessas proteases para aplicações industriais e biotecnológicas.

Escherichia coli expression and characterization of α-amylase from Geobacillus thermodenitrificans DSM-465 / Expressão e caracterização de Escherichia coli de alfa-amilase de Geobacillus thermodenitrificans DSM-465

Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% α-helices, 15% ß-sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (∆G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.

A alfa-amilase, que catalisa a hidrólise do amido, é uma enzima ubíqua com imensas aplicações industriais. Um gene de 1698 pb que codifica a amilase de 565 aminoácidos foi amplificado por PCR, a partir de Geobacillus thermodenitrificans DSM-465, clonado no plasmídeo pET21a (+), expresso na cepa BL21 (DE3) de E. coli e caracterizado. A enzima recombinante exibiu peso molecular de 63 kDa, pH ótimo igual a 8, temperatura ótima de 70° C e valor KM de 157,7 µM. Em escala piloto, a enzima purificada removeu com eficiência até 95% de amido do tecido de algodão, indicando sua capacidade de desengomagem em alta temperatura. O modelo 3D da enzima construída por Raptor-X e validada por Ramachandran plot apareceu como um monômero com 31% de hélices alfa, 15% de folhas beta e 52% de loops. Os estudos de docking mostraram melhor afinidade de ligação da enzima com amilopectina (∆G: - 10,59). De acordo com nossos resultados, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276 e Arg175 constituem o sítio ativo potencial da enzima.