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1.
Braz. j. biol ; 83: e243874, 2023. graf
Article in English | LILACS, VETINDEX | ID: biblio-1285606

ABSTRACT

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.


Subject(s)
Bacillus/metabolism , Bacillus pumilus/metabolism , Sewage , Temperature , Dietary Fiber , Endo-1,4-beta Xylanases/metabolism , Fermentation , Hydrogen-Ion Concentration
2.
Rev. flum. odontol ; 3(59): 107-116, set.-dez. 2022. ilus
Article in English | LILACS, BBO | ID: biblio-1390758

ABSTRACT

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.


Subject(s)
Tooth Erosion , Beverages , Hydrogen-Ion Concentration , Dental Enamel
3.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 323-342, mayo 2022. tab, ilus
Article in English | LILACS | ID: biblio-1396881

ABSTRACT

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.


Subject(s)
Animals , Mice , Oils, Volatile/pharmacology , Fabaceae/chemistry , Anti-Inflammatory Agents/pharmacology , Rheology , Surface-Active Agents , Temperature , Oils, Volatile/chemistry , Toxicity Tests, Acute , Emulsions/pharmacology , Nanoparticles , Polycyclic Sesquiterpenes/analysis , Hydrogen-Ion Concentration , Gas Chromatography-Mass Spectrometry
4.
Braz. j. biol ; 82: e244735, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249280

ABSTRACT

Abstract L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as ∆G - 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.


Resumo A L-asparaginase, que catalisa a degradação da L-asparagina em L-aspartato e amônia, é uma enzima de importância terapêutica no tratamento do câncer, especialmente dos linfomas e da leucemia. O presente estudo descreve a produção recombinante, propriedades e potencial anticancerígeno da enzima de Pyrococcus abyssi, um archaeon hipertermofílico. Existem dois genes que codificam para a asparaginase no genoma desse organismo. Um gene de 918 bp, que codifica 305 aminoácidos, foi amplificado por PCR e clonado na cepa BL21 (DE3) de E. coli usando o plasmídeo pET28a (+). A produção da enzima recombinante foi induzida sob 0,5mM de IPTG, purificada por desnaturação seletiva por calor e cromatografia de troca iônica. A enzima purificada foi analisada quanto à cinética, estrutura in silico e propriedades anticancerígenas. A enzima recombinante apresentou peso molecular de 33 kDa, atividade específica de 1.175 U / mg, valor de KM 2,05 mM, temperatura ótima de 80º C e pH 8. Nenhuma atividade enzimática detectável foi encontrada quando a L-glutamina foi usada como substrato. Estudos in silico mostraram que a enzima existe como um homodímero, com Arg11, Ala87, Thr110, His112, Gln142, Leu172 e Lys232 sendo os resíduos do local ativo putativo. A mudança de energia livre calculada por estudos de docking molecular da enzima e do substrato foi encontrada como ∆G - 4,5 kJ / mol, indicando a afinidade da enzima com o substrato. Valores de IC50 de 5U / mL a 7,5U / mL foram determinados para células FB, células caco2 e células HepG2. Uma quantidade de enzima (5U / mL) apresentou inibição de crescimento de 78% a 55% das células caco2 e HepG2, respectivamente. Em conclusão, a enzima recombinante produzida e caracterizada no presente estudo é uma boa possibilidade para o tratamento do câncer. Os procedimentos adotados na presente pesquisa podem ser aplicados para estudos in vivo.


Subject(s)
Humans , Asparaginase/biosynthesis , Asparaginase/pharmacology , Pyrococcus abyssi/enzymology , Antineoplastic Agents/pharmacology , Substrate Specificity , Enzyme Stability , Recombinant Proteins/biosynthesis , Recombinant Proteins/pharmacology , Caco-2 Cells , Escherichia coli/genetics , Molecular Docking Simulation , Hydrogen-Ion Concentration
5.
Braz. j. biol ; 82: e239449, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249271

ABSTRACT

Abstract 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 DSM-465, 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% β-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.


Resumo 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.


Subject(s)
Escherichia coli/genetics , alpha-Amylases/genetics , alpha-Amylases/metabolism , Temperature , Enzyme Stability , Cloning, Molecular , Geobacillus , Hydrogen-Ion Concentration
6.
Braz. j. biol ; 82: e234413, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249269

ABSTRACT

Abstract The viscera and other residues from fish processing are commonly discarded by the fishing industry. These by-products 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.


Resumo 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


Subject(s)
Peptide Hydrolases , Stomach , Temperature , Hydrogen-Ion Concentration
7.
Braz. j. biol ; 82: e234500, 2022. tab, graf
Article in English | LILACS | ID: biblio-1153464

ABSTRACT

Abstract 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.


Resumo 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.


Subject(s)
Animals , Peptide Hydrolases , Temperature , Hydrogen-Ion Concentration
8.
Bol. malariol. salud ambient ; 62(3): 383-396, 2022. tab, graf
Article in Spanish | LILACS, LIVECS | ID: biblio-1395368

ABSTRACT

En la investigación se determinaron la presencia de geohelmintos y se evaluó la calidad ambiental del suelo mediante parámetros fisicoquímicos en el distrito de José Crespo y Castillo ­ Huánuco, Perú. Se detectaron y cuantificaron los geohelmintos, se caracterizó los perfiles modales y propiedades fisicoquímicas en función del Soil Taxonomy, y contraste con el estándar de calidad para el cadmio (Cd) y determinación del índice de calidad ambiental del suelo empleando el análisis de componentes principales. Los perfiles modales son Fluventic Eutrudepts, Lithic Udorthents, Typic Dystrudepts, Typic Dystrudepts - Lithic Udorthents, Typic Dystrudepts - Typic Endoaquents, Typic Endoaquents, Typic Eutrudepts - Typic Eutrudepts, Typic Udifluvents y Typic Udorthents; los parámetros fisicoquímicos textura, pH, materia orgánica, nitrógeno, fosforo disponible, potasio disponible, cadmio disponible, capacidad de intercambio catiónico efectivo, calcio, magnesio, aluminio, hidrogeno, bases y ácidos cambiables y porcentaje de saturación de aluminio, determinando que el cadmio disponible se encuentra dentro de los estándares de calidad ambiental del Perú; y el índice de calidad ambiental del suelo es de 41,48%, teniendo la calificación de un suelo regular de calidad ambiental. Y la contaminación por Ascaris lumbricoides fue en 25 de las calicatas (55,56%), presente en los 8 tipos de suelos catalogados, seguida de las unicinarias representadas por Necator americano y Ancylostoma duodenale en 14 calicatas (31,11%) de pH ligeramente a medianamente acido, y Taenias y Capilaria, ambos en el 8,29%; los geohelmintos como riesgo de salud pública, permanecen por largo de tiempo en el suelo, independientemente de la calidad y en amplios rangos de pH, favorecidos por niveles de sustratos orgánicos derivados de la antropogénesis(AU)


In the investigation, the presence of geohelminths was determined and the environmental quality of the soil was evaluated through physicochemical parameters in the district of José Crespo y Castillo - Huánuco, Peru. Geohelminths were detected and quantified and the modal profiles and physicochemical properties were characterized based on the Soil Taxonomy, and contrast with the quality standard for cadmium (Cd) and determination of the environmental quality index of the soil using the main component analysis. Modal profiles are Fluventic Eutrudepts, Lithic Udorthents, Typic Dystrudepts, Typic Dystrudepts - Lithic Udorthents, Typic Dystrudepts - Typic Endoaquents, Typic Endoaquents, Typic Eutrudepts - Typic Eutrudepts, Typic Udifluvents, and Typic Udorthents; the physicochemical parameters texture, pH, organic matter, nitrogen, available phosphorus, available potassium, available cadmium, effective cation exchange capacity, calcium, magnesium, aluminium, hydrogen, exchangeable bases and acids and percentage of aluminum saturation, determining that cadmium available is within the environmental quality standards of Peru; and the environmental quality index of the soil is 41.48%, having the qualification of a regular soil of environmental quality. And the contamination by Ascaris lumbricoides was in 25 of the pits (55.56%), present in the 8 types of cataloged soils, followed by the unicinarias represented by Necator americano and Ancylostoma duodenale in 14 pits (31.11%) of pH slightly to medium acid, and Taenias and Capilaria, both at 8.29%; As a public health risk, geohelminths remain in the soil for a long time, regardless of quality and in wide pH ranges, favored by levels of organic substrates derived from anthropogenesis(AU)


Subject(s)
Agricultural Zones , Environmental Quality , Environmental Pollution , Indicators and Reagents , Reference Standards , Cadmium , Hydrogen-Ion Concentration
9.
Braz. J. Pharm. Sci. (Online) ; 58: e191093, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383999

ABSTRACT

Abstract In recent years, improvements have been made, through biotechnological processes, in the production and development of peptides capable of increasing collagen and elastin synthesis for anti-aging skin care. However, proteins have many limitations due to their structural, chemical and physical fragility to external aggressions, which may cause conformational changes, leading to loss of biological activity. Therefore, it is important to create delivery systems that protect these biomolecules from damage, allowing them to reach their target. This work aimed to develop a system able to carry bovine serum albumin (BSA), used as a model of a protein, and to incorporate this system in a semisolid formulation suitable for skin application. A microemulgel based on a solid-in-oil-in-water (S/O/W) microemulsion was prepared. Firstly, the association efficiency (AE) of lyophilized BSA-sucrose ester complex and the size of S/O nanodispersion were assessed; then, the characterization and stability evaluation of the final semisolid formulation through evaluation of pH, texture and rheological behavior were performed. The average value of AE was 54.74% ± 2.17. It was possible to develop an S/O/W microemulsion, which allowed the subsequent development of an S/O/W microemulgel that assured suitable pH, texture and rheological characteristics for skin application.


Subject(s)
Serum Albumin, Bovine , Proteins/adverse effects , Collagen , Peptides/agonists , Skin/drug effects , Biological Products , Aging , Hydrogen-Ion Concentration
10.
Rev. odontol. UNESP (Online) ; 51: e20220006, 2022. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1377173

ABSTRACT

Introduction: Pharmaceutical pediatric formulations with low in pH and high in total titratable acidicity used frequently and over long periods of time, have the potential to produce erosive lesions in teeth. On the other hand, high concentration of sucrose, the nocturnal use and the lack of hygiene after its administration, are some factors that can contribute to the cariogenic potential of these formulations. Objective: To evaluate in vitro the cariogenic and erosive potential of medicines and liquid vitamins and mineral supplements for pediatric use. Material and method: Medicines (n=41) and liquid vitamins and mineral supplements (n=12) childish were selected and analyzed for their physicochemical properties, pH, total titratable acidity (TTA) and total soluble solids concentration (TSS/°Brix). The package inserts and labels were analyzed to identify the composition regarding the content of sugars and acidulants, in addition to the side effects related to salivary flow. Result: The pH analysis indicated that there was greater variation in the observed averages in the medication group. As for the TTA at pH 5.5, supplements and medicines groups showed significant variation between the means found (p<0.05). The TTA results at pH 7.0 showed that the highest mean found was in the class of antihistamines and the lowest in the class of drugs that contain the association of antitussives and antihistamines. The analyses TSS demonstrated that across all drug classes and supplements the amount of TSS varied significantly (p<0.05) in all classes of medicines and supplements. Conclusion: Most medicines and pediatric liquid vitamin and mineral supplements demonstrated significantly different behaviors within the group itself regarding the variables analyzed that constitute risk factors for the development of dental caries and erosion.


Introdução: Formulações farmacêuticas pediátricas com baixo pH e alta acidez titulável usadas com frequência e por longos períodos de tempo têm potencial para produzir lesões erosivas nos dentes. Por outro lado, alta concentração de sacarose, uso noturno e falta de higiene bucal após a administração são fatores que podem contribuir para o potencial cariogênico dessas formulações. Objetivo: Avaliar in vitro o potencial cariogênico e erosivo de medicamentos e suplementos vitamínicos e minerais líquidos de uso pediátrico. Material e método: Medicamentos (n=41) e suplementos vitamínicos e minerais (n=12) líquidos infantis foram selecionados e analisados quanto às suas propriedades físico-químicas, pH, acidez total titulável (ATT) e concentração de sólidos solúveis totais (SST/°Brix). Bulas e rótulos foram analisados para a identificação do conteúdo em açúcares e acidulantes, além dos efeitos colaterais relacionados ao fluxo salivar. Resultado: A análise do pH indicou que no grupo medicamentos houve maior variação nas médias observadas. Quanto à ATT em pH 5,5, os grupos medicamentos e suplementos apresentaram variação significativa entre as médias (p<0,05). Os resultados da ATT em pH 7,0 demonstraram que a maior média encontrada foi na classe dos anti-histamínicos e a menor na classe dos medicamentos que contém a associação de antitussígenos e anti-histamínicos. A análise de SST demonstrou que em todas as classes de medicamentos e nos suplementos a quantidade de SST variou significativamente (p<0,05). Conclusão: Os medicamentos e suplementos vitamínicos e minerais líquidos apresentaram comportamentos diferentes dentro do mesmo grupo quanto às variáveis analisadas, apresentando potencial cariogênico e erosivo em sua maioria.


Subject(s)
Sucrose , Tooth Erosion , Pharmaceutical Preparations , Child , Histamine Antagonists , Hydrogen-Ion Concentration , Oral Hygiene , In Vitro Techniques , Analysis of Variance
11.
Braz. j. biol ; 82: e244496, 2022. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1278474

ABSTRACT

Abstract Enzymes immobilized onto substrates with excellent selectivity and activity show a high stability and can withstand extreme experimental conditions, and their performance has been shown to be retained after repeated uses. Applications of immobilized enzymes in various fields benefit from their unique characteristics. Common methods, including adsorption, encapsulation, covalent attachment and crosslinking, and other emerging approaches (e.g., MOFs) of enzyme immobilization have been developed mostly in recent years. In accordance with these immobilization methods, the present review elaborates the application of magnetic separable nanoparticles and functionalized SBA-15 and MCM-41 mesoporous materials used in the immobilization of enzymes.


Resumo Enzimas imobilizadas em substratos com excelente seletividade e atividade apresentam alta estabilidade e podem suportar condições experimentais extremas, e seu desempenho foi mantido após repetidos usos. As aplicações de enzimas imobilizadas em vários campos se beneficiam de suas características únicas. Métodos comuns, incluindo adsorção, encapsulamento, ligação covalente e reticulação, e outras abordagens emergentes (por exemplo, MOFs) de imobilização de enzima, foram desenvolvidos principalmente nos últimos anos. De acordo com esses métodos de imobilização, a presente revisão elabora a aplicação de nanopartículas magnéticas separáveis ​​e materiais mesoporosos funcionalizados SBA-15 e MCM-41 usados ​​na imobilização de enzimas.


Subject(s)
Enzymes, Immobilized/metabolism , Magnetite Nanoparticles , Enzyme Stability , Adsorption , Hydrogen-Ion Concentration
12.
Braz. J. Pharm. Sci. (Online) ; 58: e19373, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384009

ABSTRACT

Abstract The main purposes of the current study were to formulate o/w nanoemulsions as a carrier for Tamarindus indica (tamarind) fruit pulp extract and to study the antioxidant and antibacterial potentials of nanoemulsions containing tamarind extract, focusing on cosmetic/hygiene applications. The o/w nanoemulsions using a mixture of Tween 80 and Span 80 as an emulsifier (5%w/w) were prepared by a high pressure homogenization process. Two concentrations of sweet tamarind extract, 3.3 and 6.6%w/w, based on the bioactivity study, were incorporated into the blank nanoemulsions to produce loaded nanoemulsions, F1-3.3TE (3.3%) and F1- 6.6TE (6.6%). As compared with the unloaded nanoemulsion, both tamarind extract loaded nanoemulsions showed reduced pH and significantly increased viscosity. Overall, the loaded nanoemulsions had droplet sizes of approximately 130 nm, zeta potential around -38 mV and polydispersity index (PDI) values less than 0.2. The nanoemulsion F1-3.3TE had better stability (e.g. significantly greater % tartaric acid content and lesser PDI value) than the nanoemulsion F1-6.6TE did. The antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay revealed that the nanoemulsions F1-3.3TE and F1-6.6TE had scavenging activities of 81.66 ± 0.77% and 63.80 ± 0.79%, respectively. However, antioxidant activity of these two formulations decreased under stress conditions (heating-cooling cycles). Such incidence did not occur for their antibacterial properties investigated by agar well diffusion technique. The two formulations exhibited inhibition zones of approximately 24.0-27.7 mm against Staphylococcus aureus and Staphylococcus epidermidis, responsible for malodor of underarms. The results suggest the potential of using sweet tamarind pulp extract loaded nanoemulsions as hygiene products.


Subject(s)
Tamarindus/adverse effects , Fruit/classification , Anti-Bacterial Agents/analysis , Antioxidants/analysis , Staphylococcus aureus/classification , Staphylococcus epidermidis/classification , zeta Potential , Heating/instrumentation , Hydrogen-Ion Concentration , Methods
13.
Braz. J. Pharm. Sci. (Online) ; 58: e18984, 2022. graf
Article in English | LILACS | ID: biblio-1364429

ABSTRACT

Interferon-ß-1a (INF-ß-1a) has gained significant attention due to its emerging applications in the treatment of different human diseases. Therefore, many researchers have attempted to produce it in large quantities and also in a biologically active form using different expression systems. In the present study, we aimed to improve the expression level of INF-ß-1a by Pichia pastoris using optimization of culture conditions. The codon-optimized INF-ß- 1a gene was cloned into pPICZαA plasmid under the control of alcohol oxidase I (AOX1) promoter. The protein expression was induced using different concentrations of methanol at different pHs and temperatures. The biological activity of produced protein was evaluated by anti-proliferative assay. The ideal culture conditions for the expression of INF-ß-1a by P. pastoris were found to be induction with 2% methanol at pH 7.0 culture medium at 30 C which yielded a concentration of 15.5 mg/L INF-ß-1a in a shake flask. Our results indicate that differences in glycosylation pattern could result in different biological activities as INF- ß-1a produced by P. pastoris could significantly more reduce the cell viability of HepG-2 cells, a hepatocellular carcinoma cell line, than a commercially available form of this protein produced by CHO


Subject(s)
Pichia/classification , Interferon-beta/agonists , Carcinoma, Hepatocellular/pathology , Process Optimization , Codon , Cells , Carcinoma, Hepatocellular , Hydrogen-Ion Concentration
14.
Braz. J. Pharm. Sci. (Online) ; 58: e18946, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364411

ABSTRACT

Abstract To investigate structure-property relationship of polymer-based curcumin solid dispersion (SD), three acrylic polymers were used to formulate curcumin SD by solvent evaporation method. Curcumin Eudragit EPO SD (cur@EPO), curcumin Eudragit RS PO SD (cur@RSPO) and curcumin Eudragit RL PO SD (cur@RLPO) showed deep red, golden orange and reddish orange color, respectively. Cur@RSPO entrapped 15.42 wt% of curcumin followed by cur@RL PO and cur@EPO. FTIR spectra indicated that in cur@EPO, curcumin may transfer hydrogen to the dimethylaminoethyl methacrylate group and thus change its color to red. In contrast, curcumin may form hydrogen bonding with Eudragit RS PO and Eudragit RL. Curcumin exists in amorphous state in three SDs as proved by differential scanning calorimetry and X-Ray diffraction measurement. In vitro digestion presented that lower pH value in simulated gastric fluid (SGF) stimulates the curcumin release from cur@EPO while permeability influences the release profile in other two SDs. When in simulated intestinal fluid (SIF), first order release model governs the release behaviors of all three SDs which showed sustained release pattern. Our results are helpful to elucidate how structure of polymer may impact on the major properties of curcumin contained SD and will be promising to broaden its therapeutic applications.


Subject(s)
Polymers , Curcumin/analysis , Methods , Solvents/administration & dosage , X-Ray Diffraction/instrumentation , In Vitro Techniques/methods , Calorimetry, Differential Scanning/methods , Evaporation/classification , Spectroscopy, Fourier Transform Infrared , Color , Citrus sinensis/classification , Hydrogen-Ion Concentration
16.
Rev. cuba. anestesiol. reanim ; 20(3): e720, 2021.
Article in Spanish | LILACS, CUMED | ID: biblio-1351985

ABSTRACT

Introducción: Las alteraciones del equilibrio ácido-base pueden ser de carácter primario. En la mayoría de los casos dependen de la complicación de una enfermedad preexistente. La frecuencia de estos trastornos es elevada, especialmente, en enfermos hospitalizados en las unidades de atención al paciente grave. Su aparición conlleva implicaciones pronósticas significativas. Objetivo: Sistematizar sobre el estado actual del manejo del equilibrio ácido-base. Método: Se realizó una revisión bibliográfica en la que se utilizaron las herramientas del método científico. Se examinó toda la bibliografía disponible publicada en los últimos cinco años y así, elaborar una síntesis crítica, acorde al criterio y las competencias de los autores sobre la temática. Resultados: Se expone la importancia de la evaluación clínica, que unida a los niveles de PCO2, y de exceso o déficit de bases en una gasometría arterial, permiten identificar el trastorno ácido base existente. Igualmente, se destaca que el CO2 tiene una función clave en el control de la ventilación, así como las modificaciones que produce al flujo sanguíneo cerebral, el pH y el tono adrenérgico. Otro aspecto importante fue la reciente práctica clínica de la "hipercapnia permisiva" para reducir el metabolismo tisular y de esta manera, mejorar la función del surfactante e impedir la nitración de las proteínas. Conclusiones: El manejo de los desequilibrios ácido-base debe ser del dominio de todos los profesionales vinculados a la asistencia médica, pues el retraso de su diagnóstico puede empeorar la evolución y el pronóstico de los pacientes graves(AU)


Introduction: Acid-base balance alterations can be of a primary nature. In most cases, they depend on the complication of a pre-existing disease. The frequency of these disorders is high, especially in patients hospitalized in critical care units. Its appearance carries significant prognostic implications. Objective: To systematize the current state of acid-base balance management. Method: A bibliographic review was carried out, for which the tools of the scientific method were used. All the available bibliography, published in the last five years, was examined; thus, a critical synthesis was prepared, according to the criteria and competences of the authors regarding the subject. Results: The importance of the clinical evaluation is exposed, which, together with PCO2 levels as well as excess or deficit of bases in an arterial blood gas, allow to identify the existing acid-base disorder. Likewise, it is highlighted that CO2 has a key function in ventilation control, together with the modifications it produces on cerebral blood flow, pH and adrenergic tone. Another important aspect was the recent clinical practice of "permissive hypercapnia" to reduce tissue metabolism and thus improve surfactant function and prevent protein nitration. Conclusions: The management of acid-base imbalances should be mastered by all professionals associated to medical care, since any delay in its diagnosis can worsen the evolution and prognosis of seriously ill patients(AU)


Subject(s)
Humans , Male , Female , Acid-Base Equilibrium , Acid-Base Imbalance , Blood Gas Analysis/methods , Critical Care , Medical Care , Hydrogen-Ion Concentration
17.
Bol. malariol. salud ambient ; 61(4): 642-649, dic. 2021. tab, graf
Article in Spanish | LILACS, LIVECS | ID: biblio-1395695

ABSTRACT

Nuestra cavidad bucal cuenta con características particulares como ecosistema y microbiota. Este hábitat de microorganismos es uno de los más diversos de cualquier comunidad microbiana asociada a los humanos, y además cumple ciertas funciones en los procesos biológicos y digestivos del hospedante. Aunque muchos de estos microorganismos residentes aportan beneficios, en condiciones de sinergia y exacerbación, el predominio de algunos géneros puede influir en el desarrollo de enfermedades periodontales. Se realizó una investigación cuantitativa, exploratoria, descriptiva y transversal en el de Centro de Salud de Latacunga, provincia de Cotopaxi, en Ecuador, en mujeres cuya edad oscilaba entre 45 y 55 años. Se estableció una relación lineal negativa entre la edad y el pH salival, es decir, que al aumentar la edad aumentó la acidez bucal de las pacientes. De manera similar, el pH salival influyó inversamente en la disponibilidad microbiótica, pues en las cavidades bucales más ácidas el índice de detección fue más alto en 18/25 microorganismos. Las proporciones de afecciones en la salud bucodental encontradas en las pacientes como caries (96%), gingivitis (67%), halitosis (78%) y xerostomía (56%), indican la no exclusión y superposición de las mismas, pudiendo presentarse patologías combinadas en un mismo paciente, haciendo necesario explorar de qué manera los niveles de pH y la diversidad microbiótica oral encontrados se interrelacionan, y a su vez como estas nosologías podrían tener determinantes similares(AU)


Our oral cavity has particular characteristics such as ecosystem and microbiota. This habitat of microorganisms is one of the most diverse of any microbial community associated with humans, and also fulfills certain functions in the biological and digestive processes of the host. Although many of these resident microorganisms provide benefits, under conditions of synergy and exacerbation, the predominance of some genera can influence the development of periodontal diseases. A quantitative, exploratory, descriptive and cross-sectional investigation was carried out in the Latacunga Health Center, Cotopaxi province, Ecuador, in women whose age ranged between 45 and 55 years. A negative linear relationship was established between age and salivary pH, that is, with increasing age the oral acidity of the patients increased. Similarly, salivary pH inversely influenced microbiotic availability, since in the more acidic oral cavities the detection rate was higher in 18/25 microorganisms. The proportions of conditions in oral health found in patients such as caries (96%), gingivitis (67%), halitosis (78%) and xerostomia (56%), indicate their non-exclusion and overlap, and pathologies may occur combined in the same patient, making it necessary to explore how the pH levels and oral microbiotic diversity found are interrelated, and in turn, how these nosologies could have similar determinants(AU)


Subject(s)
Humans , Female , Middle Aged , Periodontal Diseases , Oral Health , Acidity , Microbiota , Hydrogen-Ion Concentration , Xerostomia , Health Centers , Dental Caries , Ecuador/epidemiology , Gingivitis , Halitosis
18.
Electron. j. biotechnol ; 52: 30-34, July. 2021. ilus, tab, graf
Article in English | LILACS | ID: biblio-1283487

ABSTRACT

BACKGROUND: This study aimed to develop an amplification method of urea detection based on pHsensitive liposomes. RESULTS: The urease covalently immobilized on the magnetic particles and the pH-sensitive liposomes encapsulating ferricyanide were added to the cyclic-voltammeter cell solution where urea was distributed. The conversion of urea into carbonic acid seemed to induce a pH decrease that caused a reduction in the electrostatic repulsion between the headgroups of weakly acidic 1,2-dipalmitoyl-sn-glycero3-succinate. The reduction induced the liposomes to release potassium ferricyanide that was encapsulated inside. The effects of urea concentration and pH value were investigated. A specific concentration (0.5 mg/mL) of the urea solution was set to observe the response. The activity of urease was reversible with respect to the pH change between 7 and 5. The sensitivity of this detection was almost identical to the comparable techniques such as an enzyme-linked immunosorbent assay and a field-effect transistor. CONCLUSIONS: In summary, the methodology developed in this study was feasible as a portable, rapid, and sensitive method.


Subject(s)
Urea/analysis , Liposomes/chemistry , Urease/chemistry , Enzyme-Linked Immunosorbent Assay , Enzymes, Immobilized , Hydrogen-Ion Concentration
19.
Electron. j. biotechnol ; 52: 85-92, July. 2021. graf, tab
Article in English | LILACS | ID: biblio-1283600

ABSTRACT

BACKGROUND: Nonribosomal peptide synthases (NRPS) can synthesize functionally diverse bioactive peptides by incorporating nonproteinogenic amino acids, offering a rich source of new drug leads. The bacterium Escherichia coli is a well-characterized production host and a promising candidate for the synthesis of nonribosomal peptides, but only limited bioprocess engineering has been reported for such molecules. We therefore developed a medium and optimized process parameters using the design of experiments (DoE) approach. RESULTS: We found that glycerol is not suitable as a carbon source for rhabdopeptide production, at least for the NRPS used for this study. Alternative carbon sources from the tricarboxylic acid cycle achieved much higher yields. DoE was used to optimize the pH and temperature in a stirred-tank reactor, revealing that optimal growth and optimal production required substantially different conditions. CONCLUSIONS: We developed a chemically defined adapted M9 medium matching the performance of complex medium (lysogeny broth) in terms of product concentration. The maximum yield in the reactor under optimized conditions was 126 mg L-1, representing a 31-fold increase compared to the first shaking-flask experiments with M9 medium and glycerol as the carbon source. Conditions that promoted cell growth tended to inhibit NRPS productivity. The challenge was therefore to find a compromise between these factors as the basis for further process development.


Subject(s)
Peptide Synthases/metabolism , Bioreactors/microbiology , Escherichia coli , Temperature , Biotechnology , Carbon/metabolism , Models, Statistical , Electrophoresis, Polyacrylamide Gel , Bioengineering , Hydrogen-Ion Concentration
20.
Acta amaz ; 51(2): 129-138, jun. 2021.
Article in English | LILACS | ID: biblio-1353415

ABSTRACT

O conceito de rio continuo prediz que mudanças graduais na geomorfologia e hidrologia de um rio podem causar mudanças longitudinais na estrutura de comunidades aquáticas. Nesse contexto, avaliamos como variáveis ambientais (condutividade elétrica, pH, transparência e velocidade da água), fatores espaciais (distância da cabeceira e Moran's eigen vector maps ­ MEMs) e presença de barragens afetam as assembleias de peixes de pequeno porte ao longo de um trecho de 105 km do alto Rio Branco, um tributário do Rio Madeira, bacia Amazônica, Brasil. Coletas com rede de arrasto foram realizadas em 15 pontos a jusante e montante de barragens durante a estação seca de 2019. Capturamos um total de 4.330 indivíduos, distribuídos em três ordens, nove famílias e 26 espécies (e um indivíduo híbrido). Condutividade elétrica e pH foram afetados significativamente pela presença de barragens e pela distância da cabeceira. A riqueza de espécies e a abundância não variaram em função das variáveis ambientais. Ao contrário da riqueza de espécies, que não variou ao longo do trecho amostrado, a abundância apresentou uma relação negativa com a distância da cabeceira. A composição de espécies variou significativamente em resposta ao pH, a fatores espaciais lineares e à presença de barragens. Nossos resultados sugerem que a mudanças na composição de espécies de peixes de pequeno porte no alto Rio Branco ocorre devido à variação em características da água, em função da limitação na dispersão inerente das espécies e em resposta à presença de barragens(AU)


Subject(s)
Hydrographic Basins , Amazonian Ecosystem , Hydrogen-Ion Concentration
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