-In Brazil, about 25-30% of the population has some degree of intolerance to lactose, a disorder associated with the inability of the body to digest lactose due to a disability or absence of the enzyme lactase. The goal of this study was to evaluate the performance of adsorption of lactose from fresh milk using a fixed bed column of molecularly imprinted polymer (MIP). The polymeric material was characterized using Scanning electron microscopy (SEM) analysis, thermal analysis (e.g., differential scanning calorimetric (DSC) and thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), and the method of Braunauer, Emmet and Teller (BET). The adsorption column dynamics and performance were studied by the breakthrough curves using a 2 4-1 fractional factorial design. The chemical and structural characterization of the pure matrix and imprinted polymers confirmed the molecularly imprinted polymer (MIP) imprinted with lactose. The highest capacity was 62.21 mgg -1 , obtained at 307.1 K and a flow rate of 12.5 mL.min -1 , with central point conditions, 320.1 K and 9 mL.min -1 , with an average value of 50.9 mg.g -1 . The results indicate that the molecularly imprinted polymer is efficient.
ResumoIntrodução: O uso de medicações intracanais com propriedades antimicrobianas é fundamental para descontaminação dos canais radiculares durante o tratamento endodôntico. O hidróxido de cálcio é utilizado como medicação intracanal por apresentar excelentes propriedades. O óleo de Melaleuca alternifólia apresenta importância medicinal demonstrando ação antifúngica e bactericida comprovada contra patógenos humanos. Objetivo: Avaliar aspectos físico-químicos da associação do óleo de Melaleuca Alternifólia com hidróxido de cálcio, como: pH e liberação de cálcio durante diferentes períodos. Material e método: O pó do hidróxido de cálcio foi adicionado aos veículos até a concentração de 72mg/0,1mL. Foram divididos três grupos: Grupo I: Hidróxido de Cálcio + Água Destilada; Grupo II: Hidróxido de Cálcio + Propilenoglicol; Grupo III: Hidróxido de Cálcio + Óleo de Melaleuca. O pH de cada grupo foi medido após 10 minutos, 24, 48 horas, 7, 15 e 30 dias após a espatulação por um pHmetro. A liberação de cálcio foi analisada através da espectrometria de absorção atômica equipada com uma lâmpada cátodo para cálcio. Os dados foram analisados estatisticamente pelos testes de Kruskall-Wallis e Dunn. Resultado: O grupo II apresentou pH elevado, semelhante ao grupo III, permanecendo uniforme aos 15 e 30 dias. A liberação de cálcio iniciou em 24 horas, de forma semelhante nos grupos II e III e seu pico de liberação deu-se em 48 horas. Conclusão: A associação do Óleo de Melaleuca com hidróxido de cálcio apresentou bons resultados quanto à análise de pH e liberação de cálcio, demonstrando ação semelhante ao propilenoglicol + hidróxido de cálcio.Descritores: Endodontia; hidróxido de cálcio; óleo de melaleuca alternifólia.
AbstractIntroduction: The use of intracanal medications with antimicrobial properties is essential for decontaminating root canals during endodontic treatment. Calcium hydroxide is used for this because of its excellent properties. Melaleuca alternifolia oil has shown medicinal importance by demonstrating antifungal and bactericidal action against proven human pathogens. Objective: To evaluate the physical and chemical aspects such as pH and calcium release, of Melaleuca alternifolia oil associated with calcium hydroxide, during different time intervals. Material and method: Calcium hydroxide powder was added to vehicles to reach a concentration of 72mg / 0.1mL. Three groups were formed: Group I: Calcium Hydroxide + Distilled Water; Group II: Calcium hydroxide + Propylene Glycol; Group III: Calcium hydroxide + Melaleuca oil. The pH of each group was measured after time intervals of 10 minutes; 24 and 48 hours; 7, 15 and 30 days after tooling by a pH meter. Calcium release was analyzed by atomic absorption spectrometry equipped with a calcium hollow cathode lamp. Data were statistically analyzed by using the Kruskall-Wallis and Dunn test. Result: Group II showed high pH, similar to group III that remained uniform at 15 and 30 days. Calcium release that began after 24 hours, was similar in Groups II and III, and sho...
A síntese de compostos enantiomericamente puros é cada vez mais requisitada pelas indústrias farmacêutica, cosmética e agroalimentar, bem como está estabelecido a importância da quiralidade na atividade e propriedades biológicas de muitos compostos. Desta forma a biocatálise tornou-se uma alternativa viável na produção de compostos de interesse indústria. Assim o objetivo do presente estudo é avaliar as capacidades de biotransformação das folhas Morus nigra do terpenoide (+)-carvona, bem como determinar as condições biocatalíticas ideiais. Foram testadas as variáveis biomassa, concentração de substrato e pH do meio, sendo possível inferir que para todas as condições testadas as folhas de Morus nigra foram capazes de realizar hidrogenação do alceno ativado, bem como a redução da carbonila para álcool quiral. Estes resultados demonstram que a Morus nigra é uma potencial ferramenta biocatalítica para a obtenção de compostos de interesse industrial.
To evaluate pH and solubility of MTA Fillapex® cement. Material and methods: Patients were divided into four groups: GI (MTA Fillapex®), GII (Sealer 26®), GIII (Sealapex®) and GIV (AH Plus®). Samples of each group with 10 mm in diameter and 2 mm in height were immersed into water at neutral pH and kept at 37ºC. After 3 hours, the first pH measurement was carried out and repeated at 24 hour intervals for seven days. The data were submitted to Anova (p < 0.05). To analyze the solubility, specimens with 20 mm in diameter and 1.5 mm in thickness were weighed after the setting time, and maintained in distilled water at 37ºC for seven days. After this period, the specimens were again weighed. The difference between their weighs represents the mass loss. The data were subjected to Student’s t test for paired samples (p < 0.05). Results:GI and GIII showed pH increase at the first 24 hours, with a significant reduction compared with the other cements. GIV was the smallest mass loss, followed by GII, GIII and GI. Conclusion:MTA Fillapex® has higher solubility than that of resin cements, but its pH remained above 10 for seven days.
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