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1.
J Esthet Restor Dent ; 35(7): 993-1000, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36815432

RESUMEN

OBJECTIVES: Natural restorations combine digital workflow and shell technique to create CAD/CAM restorations with the form and texture of natural teeth. This case report describes an interdisciplinary digital workflow combined with CAD/CAM natural restorations to achieve the naturalness of an anterior rehabilitation. CLINICAL CONSIDERATIONS: A 38-year-old patient attended to the office with esthetic issues. An interdisciplinary treatment plan was conducted, which included periodontal surgery to recreate the gingival contour, associated with bleaching and manufacturing CAD/CAM ceramic veneers to return an optimal teeth surface texture and shape. CONCLUSIONS: The design and manufacturing of CAD/CAM natural restorations using a digital workflow allowed a predictable result and overcame the limitations of conventional shell technique. CLINICAL SIGNIFICANCE: Conventional shell technique is used to create restorations with the form and texture of natural teeth. This article presents a combination of the conventional shell technique with a digital workflow, facilitating the design and manufacturing of CAD/CAM natural restorations.


Asunto(s)
Cerámica , Diseño de Prótesis Dental , Humanos , Adulto , Flujo de Trabajo , Diseño Asistido por Computadora , Encía
2.
J Sci Food Agric ; 101(8): 3500-3507, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33274765

RESUMEN

BACKGROUND: The chemical compounds in coffee are important indicators of quality. Its composition varies according to several factors related to the planting and processing of coffee. Thus, this study proposed to use near-infrared spectroscopy (NIR) associated with partial least squares (PLS) regression to estimate quickly some chemical properties (moisture content, soluble solids, and total and reducing sugars) in intact green coffee samples. For this, 250 samples produced in Brazil were analyzed in the laboratory by the standard method and also had their spectra recorded. RESULTS: The calibration models were developed using PLS regression with cross-validation and tested in a validation set. The models were elaborated using original spectra and preprocessed by five different mathematical methods. These models were compared in relation to the coefficient of determination, root mean square error of cross-validation (RMSECV), root mean square error of test set validation (RMSEP), and ratio of performance to deviation (RPD) and demonstrated different predictive capabilities for the chemical properties of coffee. The best model was obtained to predict grain moisture and the worst performance was observed for the soluble solids model. The highest determination coefficients obtained for the samples in the validation set were equal to 0.810, 0.516, 0.694 and 0.781 for moisture, soluble solids, total sugar, and reducing sugars, respectively. CONCLUSION: The statistics associated with these models indicate that NIR technology has the potential to be applied routinely to predict the chemical properties of green coffee, and in particular, for moisture analysis. However, the soluble solid and total sugar content did not show high correlations with the spectroscopic data and need to be improved. © 2020 Society of Chemical Industry.


Asunto(s)
Coffea/química , Café/química , Semillas/química , Espectroscopía Infrarroja Corta/métodos , Brasil , Control de Calidad
3.
J Sci Food Agric ; 100(6): 2488-2493, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31960433

RESUMEN

BACKGROUND: Coffee is a raw material of global interest. Due to its relevance, this work evaluated the performance of calibration models constructed from spectral data obtained using near-infrared spectroscopy (FT-NIR) to determine the pH values and acidity in coffee beans in a practical and non-destructive way. Partial least squares regression was used during the calibration and the cross-validation to optimize the number of latent variables. The predictive capacity of the spectral pre-processing methods was also accessed. RESULTS: The results obtained showed that the best methods of pre-processing were the first derivative for the pH variable and the standard normal variate for the acidity, which produced models with correlations of 0.78 and 0.92, ratios of prediction to deviation of 2.061 and 2.966 and biases of -0.00011 and -0.152 to test set validation, respectively. The average errors between predicted and experimental values were lower than 7%. CONCLUSIONS: FT-NIR was successfully applied to predict properties related to the quality of coffee. The method was demonstrated to be a fast and non-destructive tool which allows the rapid inline evaluation of samples facilitating industrial and commercial processing. © 2020 Society of Chemical Industry.


Asunto(s)
Coffea/química , Concentración de Iones de Hidrógeno , Espectroscopía Infrarroja Corta/métodos , Calibración , Análisis de los Mínimos Cuadrados , Semillas/química
4.
J Food Sci Technol ; 56(9): 4147-4157, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31477986

RESUMEN

Color is a sensory attribute that influences the acceptance of food and dyes are added into food products to provide them attractiveness. In this context, anthocyanins have merged as an alternative to synthetic dyes. This study aimed to develop food model systems of fermented or unfermented dairy beverages containing added microencapsulated anthocyanin-rich extracts from juçara palm fruit. The stabilities of both pigment and beverage throughout storage in opaque or transparent packaging have been evaluated. Acidity, pH and anthocyanin content in both beverages did not vary during 28 days of storage, and the content of bioactive compounds did not decrease over time. A slight overall color difference that is probably invisible to naked eyes was detected between the beverages analyzed at days 0 and 28. The potential of applying microencapsulated natural pigments into dairy matrices is an effort to increase their nutritional and sensorial values.

5.
Folia Med (Plovdiv) ; 60(3): 373-380, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30355849

RESUMEN

Karl Jaspers published the first edition of 'General Psychopathology' in 1913. Now, coinciding with its 100th anniversary whose importance was consecrated through multiple congresses, we see a parallelism and a return to the dilemma of the 'Methodenstreit', which led Karl Jaspers to introduce the phenomenological method for psychopathology to understand the subjective manifestations of the mind. Phenomenology is part of the research and clinical methods in psychiatry and psychology as a way to capture the subjective in psychopathology. However, phenomenology is nowadays wrongly used. In this article, we attempt to rediscover and present in a clear way the origins and meaning of Jaspers' phenomenology, whose bases, although forgotten, remain current. This will be done by revising its fundamental concepts such as objective and subjective manifestations, understanding and its four types, causal explanation, empathy, intuition, presuppositions and preconceptions, phenomenological description and comprehensive 'seeing'.


Asunto(s)
Trastornos Mentales , Psicopatología/métodos , Aniversarios y Eventos Especiales , Historia del Siglo XX , Humanos , Psiquiatría/historia , Psiquiatría/métodos , Psicopatología/historia
6.
Actas Esp Psiquiatr ; 45(2): 56-61, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28353290

RESUMEN

The Psychotic Symptom Rating Scales (PSYRATS) is a clinical assessment tool that focuses on the detailed measurement of delusions and hallucinations in patients with psychosis. The goal of this study was to examine the psychometric properties of the Portuguese version of the PSYRATS. A sample of 92 outpatients suffering from schizophrenia or schizoaffective disorders and presenting persistent psychotic symptoms was assessed using the PSYRATS and the Positive and Negative Syndrome Scale (PANSS). Good inter-rater reliability, test-retest reliability, concurrent validity and internal consistency were found. Factor analysis of the auditory hallucinations scale items disclosed a four-factor solution: emotion characteristics and disruption factor (factor 1), a physical characteristics factor (factor 2), a control characteristics factor (factor 3) and a cognitive attribution factor (factor 4). Regarding the delusions scale items, a two-factor solution was found: cognitive interpretation and disruption factor (factor 1) and an emotional characteristics (factor 2). The Portuguese version of the PSYRATS partially replicates previously published results in other countries.


Asunto(s)
Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/diagnóstico , Adulto , Femenino , Humanos , Masculino , Psicometría , Traducciones
7.
J Environ Manage ; 166: 429-39, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26555099

RESUMEN

Searches related to global warming have provided important insights into the response of terrestrial ecosystems, but few have examined the impacts on agricultural crops, particularly those associated with the monitoring of agrotoxin residues. In this context, the agriclimatological zoning is an important tool in the planning and consolidation of crops and should be considered in any initiative that involves such planning. This tool is particularly important in the analysis of agrotoxin residues and may be applied by the Program Analysis of Agrotoxin Residues in Food (PARA) created by the National Health Vigilance Agency of Brazil (ANVISA), which enables greater food security and contributes to the improvement of human health. The aim of this study was to elaborate the current and future agriclimatological zoning for the tomato crop, relating it with the monitoring of samples collected by PARA in Espírito Santo State, Brazil. The results indicate that a temperature increase of 5 °C creates a decrease in apt areas from 37.3% to 4.3%, for a total reduction of 33 percentage points (-88.5%). It is noted that of the 41 producing municipalities, only 26 have apt areas greater than 50%, highlighting the municipalities with apt areas greater than 90%, represented by Mantenópolis (100%), Guaçuí (98.5%), São José do Calçado (97.8%), Irupi (94.4%), Santa Teresa (92.3%), and Marechal Floriano (91.4%). The veracity of agriclimatological zoning is proved by a Kendall rank correlation coefficient of 0.876, indicating that the distribution of the variables of apt areas and productivity are similar at the significance level of 0.05 with a confidence interval 95%. After validation of the agriclimatological zoning for the tomato crop, it is recommended that the PARA should monitor 36 municipalities rather than the current 18, representing an increase of 100%. The methodology can be adjusted to agricultural crops of other countries.


Asunto(s)
Productos Agrícolas , Contaminación de Alimentos/análisis , Sistemas de Información Geográfica , Solanum lycopersicum , Brasil , Ecosistema , Monitoreo del Ambiente , Análisis de los Alimentos/métodos , Calentamiento Global
8.
Food Res Int ; 189: 114567, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38876609

RESUMEN

This work incorporated bioactives extracted from jabuticaba peel in the form of concentrated extract (JBE) and microencapsulated powders with maltodextrin (MDP) and gum arabic (GAP) in a dairy drink, evaluating its stability, in vitro bioaccessibility, and glycemic response. We evaluated the pH, acidity, colorimetry, total phenolics and anthocyanins, antioxidant capacity, degradation kinetics and half-life of anthocyanins, bioaccessibility, and postprandial glycemic physicochemical characteristics response in healthy individuals. The drinks incorporated with polyphenols (JBE, GAP, and MDP) and the control dairy drink (CDD) maintained stable pH and acidity over 28 days. In color, the parameter a*, the most relevant to the study, was reduced for all formulations due to degradation of anthocyanins. Phenolic and antioxidant content remained constant. In bioaccessibility, we found that after the gastrointestinal simulation, there was a decrease in phenolics and anthocyanins in all formulations. In the glycemic response, we observed that the smallest incremental areas of glucose were obtained for GAP and JBE compared to CDD, demonstrating that polyphenols reduced glucose absorption. Then, the bioactives from jabuticaba peel, incorporated into a dairy drink, showed good storage stability and improved the product's functional aspects.


Asunto(s)
Antocianinas , Antioxidantes , Goma Arábiga , Polifenoles , Polisacáridos , Polifenoles/análisis , Humanos , Polisacáridos/química , Antioxidantes/análisis , Goma Arábiga/química , Antocianinas/análisis , Extractos Vegetales/química , Productos Lácteos/análisis , Glucemia/metabolismo , Frutas/química , Disponibilidad Biológica , Concentración de Iones de Hidrógeno , Digestión , Myrtaceae/química , Composición de Medicamentos , Índice Glucémico , Femenino , Masculino , Adulto
9.
Food Res Int ; 151: 110844, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34980382

RESUMEN

The Hedonic Threshold Methodology (HTM), through the determination of compromised acceptance threshold (CAT) and hedonic rejection threshold (HRT), has several applications by the food industry. In order to further increase the field of application of HTM, the objective was to use a mixture design in the Hedonic Threshold Methodology, to enable the determination of hedonic thresholds (CAT and HRT) by varying the intensity of three stimuli simultaneously. It was investigated how much it is possible to replace the NaCl content (1.8% flour weight basis) with two other ingredients (KCL/yeast extract or KCL/enzyme preparation), without compromising the acceptance (CAT) and without resulting in sensory rejection (HRT) of crackers. Reduction in the acceptance started to occur by reducing the NaCl content by around 64% (from 1.81% to 0.651%), with the addition of 1.149% KCl. Two combinations of KCl and yeast extract (1.783% and 0.017%, or 0.693% and 1.107%, respectively) allowed producing a cracker with no NaCl without sensory rejection. The reduction in acceptance also started to occur by reducing the NaCl content by around 40% (from 1.81% to 1.086%), with adding of 0.358% KCl and 0.356% enzyme preparation. A sensory rejection begins to occur by reducing the NaCl content by around 99% (1.81-0.012%), with the addition of 1.215% KCl and 0.573% enzyme preparation (transglutaminase). The use of the mixture design in HTM allowed the unprecedented determination of hedonic thresholds varying three stimuli. This expands the possibilities for applications of sensory thresholds.


Asunto(s)
Cloruro de Sodio , Gusto , Alimentos , Umbral Sensorial
10.
J Food Sci ; 87(9): 4056-4067, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35986622

RESUMEN

Spent coffee grounds (SCG) are a coproduct that causes environmental impacts worldwide. Thus, consciously reusing the SCG is an eminent need. This work aimed to encapsulate phenolic compounds and antioxidants obtained from SCG extracts through spray- and freeze-drying techniques using different isolated and combined wall materials. The dried powders produced were evaluated for moisture content, water activity, bulk density, hygroscopicity, color, content of phenolic compounds and antioxidants, and the results were compared. The results showed that all evaluated treatments resulted in a powdered product with low values of bulk density, moisture and water activity, especially for freeze-drying. The freeze-dried product also showed higher hygroscopicity. Regarding the content of phenolic compounds and antioxidants, both drying methods showed high levels of these compounds in the dried product and good encapsulation efficiency, reaching 83.43%. In most cases, spray-drying and freeze-drying did not differ statistically (p > 0.05) in relation to bioactive compound content and encapsulation efficiency. In relation to wall materials, albumin showed the worst performance in the retention of bioactive compounds. On the other hand, pure gum arabic combined with maltodextrin led to better preservation of these compounds. PRACTICAL APPLICATION: Spent coffee grounds are a coproduct generated in large quantities in the world. The encapsulation of phenolic and antioxidant compounds protects and enables their application in different food matrices. Therefore, the evaluation of different encapsulation methods and wall materials is important to define good process conditions.


Asunto(s)
Antioxidantes , Café , Albúminas , Antioxidantes/análisis , Goma Arábiga , Fenoles/análisis , Polvos , Agua
11.
Artículo en Inglés | MEDLINE | ID: mdl-36293801

RESUMEN

This study aimed to investigate the effect of spray drying (SD) and freeze-drying (FD) on the microencapsulation of green coffee extracts by using polydextrose (PD) and inulin (IN) as encapsulating agents and their physicochemical, bioactive compounds' stability, phenolic compounds' bioaccessibility after digestion, and sensory effects in unfermented dairy beverages. The extract encapsulated with IN by FD had lower moisture content, water activity, and hygroscopicity, while particles encapsulated by SD exhibited a spherical shape and the structure of the FD products was irregular. No difference was observed in phenolic compounds' bioaccessibility. Dairy beverages with added encapsulated extracts had higher total phenolic content and antioxidant activity. Microencapsulation allowed a controlled release of the bioactive compounds with an increase in the content of caffeine, chlorogenic acid, and trigonelline during storage. The dairy beverage with added extract encapsulated with IN by FD had the highest scores of acceptability regarding the overall impression and purchase intent.


Asunto(s)
Coffea , Extractos Vegetales , Antioxidantes/química , Bebidas , Cafeína/análisis , Ácido Clorogénico/análisis , Preparaciones de Acción Retardada , Inulina/química , Fenoles/química , Extractos Vegetales/química , Productos Lácteos
12.
Soc Psychiatry Psychiatr Epidemiol ; 46(5): 425-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20300728

RESUMEN

BACKGROUND: Mental health policies throughout the world are being subjected to several changes due to increased pressure from the public and from health administrators. Mental health policies in the developing world experienced changes following advice and consultation from the World Health Organization (WHO). This was the case with Brazil, which enacted several laws and policies affecting community care and the closure of beds in psychiatric hospitals (the deinstitutionalization movement). Rio Grande do Sul, the southeast state in Brazil, adopted this policy in 1992, but still suffers from a shortage of psychiatric beds in both general hospitals (GHs) and psychiatric hospitals (PHs), despite advances in the provision of community care. As a result, Rio Grande do Sul (RS) can be studied as an example of "what actually happens" in mental health care in the developing world. METHODS: The study analyzed online administrative data from 2000 to 2007 for three main parameters of mental health care (i.e. hospital use rate, length of stay, and hospital bed capacity). These were used to evaluate differences in psychiatric care among GHs and PHs. The number of existing and required psychiatric beds in RS was also calculated. RESULTS: GHs had very low hospital use rates, while PHs had a very high length of stay (200% higher than GH). The number of admissions to GHs grew by 170% over the 8 year period, and psychiatric bed availability was 1.5 per 10,000 inhabitants. CONCLUSIONS: The study provided evidence for the need of 30-50% more psychiatric beds in GHs. Also, additional staff training is needed to increase use rates in GHs and decrease the length of stay in PHs. Additional studies covering national data must be carried out to assess the extent of these problem in other Brazilian mental health care services.


Asunto(s)
Ocupación de Camas/estadística & datos numéricos , Reforma de la Atención de Salud , Hospitales/estadística & datos numéricos , Trastornos Mentales/terapia , Servicios de Salud Mental/estadística & datos numéricos , Brasil , Desinstitucionalización , Países en Desarrollo , Capacidad de Camas en Hospitales/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Hospitales Psiquiátricos/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos
13.
Early Interv Psychiatry ; 15(1): 206-212, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32052567

RESUMEN

Comprehensive social cognition training programs have been effective to improve social cognition in people with chronic schizophrenia, although there is insufficient quality evidence for recent-onset psychosis. The aim of this study was to assess the effects of Social Cognition and Interaction Training (SCIT) in a sample of recent-onset schizophrenia outpatients. Sixteen participants who had their first psychotic episode for less than 2 years were randomly allocated to the SCIT group during 20 weeks (weekly sessions) or to a psychoeducation group and completed baseline and post-training assessment for cognitive biases, social cognition, clinical symptoms and functioning. Permutation-based analysis revealed improvements in overall functioning (P = 0.036) and blame score (P = 0.070) in the SCIT group compared to the psychoeducation intervention, with large effect sizes (d = 1.438 and d = 1.204, respectively). There were also large effect sizes for hostility, emotion recognition, social perception, positive and total symptoms (d = 0.833-1.158). These results suggest that SCIT may be an effective tool to improve attributional biases and functional outcomes in recent-onset schizophrenia outpatients. Future controlled trials with larger sample size and follow-up assessments should be developed to further understand effective intervention outcomes for this population.


Asunto(s)
Terapia Cognitivo-Conductual , Trastornos Psicóticos , Esquizofrenia , Cognición , Humanos , Esquizofrenia/terapia , Cognición Social , Percepción Social
14.
Food Res Int ; 150(Pt A): 110798, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34865813

RESUMEN

Excessive sodium consumption is a worldwide public health concern. The substitution of sodium chloride (NaCl) for potassium chloride (KCl) has been adopted to reduce the sodium concentration in processed foods. The challenge is to make this substitution without affecting the sensory acceptance of foods. In this context, the objective was to determine from which concentrations the replacement of NaCl by KCl results in reduced acceptance (compromised acceptance threshold - CAT) and begins the sensory rejection (hedonic rejection threshold - HRT) of cracker-type biscuits. Using the hedonic thresholds methodology (HTM) by varying a stimulus, CAT and HRT were determined for the concentration of NaCl in crackers and, by varying two stimuli, CAT and HRT, for replacing NaCl with KCl in crackers were determined. Without the addition of KCl, the reduction in acceptance started to occur by reducing the NaCl content by around 60% (from 1.81% to 0.73%); and sensory rejection began to appear by reducing the NaCl content by approximately 93% (1.81% to 0.13%). Reduction in the acceptance started to occur by lowering the NaCl content by around 78% (from 1.81% to 0.397%), with the addition of 0.896% KCl. In addition, by adding KCl, it was possible to reduce 100% NaCl without sensory rejection of the crackers. With these results, cracker industries can reduce the sodium content of their products, contributing to the reduction of population salt intake.


Asunto(s)
Cloruro de Sodio , Gusto , Comida Rápida , Cloruro de Potasio , Sodio
15.
J Lipid Res ; 51(5): 1218-27, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19965589

RESUMEN

Methods used for lipid analysis in embryos and oocytes usually involve selective lipid extraction from a pool of many samples followed by chemical manipulation, separation and characterization of individual components by chromatographic techniques. Herein we report direct analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of single and intact embryos or oocytes from various species. Biological samples were simply moisturized with the matrix solution and characteristic lipid (represented by phosphatidylcholines, sphingomyelins and triacylglycerols) profiles were obtained via MALDI-MS. As representative examples, human, bovine, sheep and fish oocytes, as well as bovine and insect embryos were analyzed. MALDI-MS is shown to be capable of providing characteristic lipid profiles of gametes and embryos and also to respond to modifications due to developmental stages and in vitro culture conditions of bovine embryos. Investigation in developmental biology of the biological roles of structural and reserve lipids in embryos and oocytes should therefore benefit from these rapid MALDI-MS profiles from single and intact species.


Asunto(s)
Embrión de Mamíferos/química , Lípidos/análisis , Oocitos/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Bovinos , Embrión de Mamíferos/embriología , Desarrollo Embrionario , Femenino , Humanos , Especificidad de la Especie
17.
Front Psychiatry ; 9: 64, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29593578

RESUMEN

There are several reasons why a definition for mental disorder is essential. Among these are not only reasons linked to psychiatry itself as a science (nosology, research) but also to ethical, legal, and financial issues. The first formal definition of mental disorder resulted from a deep conceptual analysis led by Robert Spitzer. It emerged to address several challenges that psychiatry faced at the time, namely to serve as the starting point for an atheoretical and evidence-based classification of mental disorders, to justify the removal of homosexuality from classifications, and to counter the arguments of antipsychiatry. This definition has been updated, with some conceptual changes that make it depart from the main assumptions of Spitzer's original definition. In this article, we intend to review the factors that substantiated the emergence of the first formal definition of mental disorder that based all its later versions.

18.
Int J Biol Macromol ; 113: 395-402, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29499264

RESUMEN

A central composite design was used to determine effects of pH (1.16-2.84), extraction temperature (63-97°C) and time (35-85min) on the yield, degree of degree of esterification (DE) and viscosity of pectins extracted. For pectin extraction, the previously sanitized mango shells were dried and crushed to obtain the flour that was treated with an ethanol solution obtaining the alcohol insoluble residue (AIR). Subsequently, the AIR was mixed in ethanol with the extraction solution of hydrochloric acid. Pectin yields ranged from 18.8 to 32.1g/100g of AIR, whereas the degree of esterification (DE) and viscosity values ranged from 62.2 to 86.2% and from 1.58 to 45.85mPa·s, respectively. An inverse correlation was found between extraction yield and viscosity. Relying upon the desirability function, two optimum conditions were determined: 35min30% from the AIR, DE≥70.0% and η≥20.0mPa·s.


Asunto(s)
Fraccionamiento Químico/métodos , Mangifera/química , Pectinas/aislamiento & purificación , Esterificación , Ácidos Hexurónicos/química , Pectinas/química , Temperatura , Factores de Tiempo , Viscosidad
19.
J Agric Food Chem ; 66(1): 323-330, 2018 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-29286652

RESUMEN

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 µg mL-1. Most of the tested compounds presented MIC values ≤220 µg mL-1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Fenol/farmacología , Antibacterianos/química , Cimenos , Escherichia coli/efectos de los fármacos , Eugenol/química , Eugenol/farmacología , Listeria/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Monoterpenos/química , Monoterpenos/farmacología , Fenol/síntesis química , Fenol/química , Salmonella typhimurium/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Timol/química , Timol/farmacología
20.
Artículo en Inglés | MEDLINE | ID: mdl-16750942

RESUMEN

Hydrophobic adsorption equilibrium data of the hen egg white proteins albumin, conalbumin, and lysozyme were obtained in batch systems, at 25 degrees C, using the Streamline Phenyl resin as adsorbent. The influence of three types of salt, NaCl, Na(2)SO(4), or (NH(4))(2)SO(4), and their concentration on the equilibrium data were evaluated. The salt Na(2)SO(4) showed the higher interaction with the studied proteins, thus favoring the adsorption of proteins by the adsorbent, even though each type of salt interacted in a distinct manner with each protein. The isotherm models of Langmuir, Langmuir exponential, and Chen and Sun were well fitted to the equilibrium data, with no significant difference being observed at the 5% level of significance. The mass transfer model applied simulated correctly adsorption kinetics of the proteins under the studied conditions.


Asunto(s)
Albúminas/química , Conalbúmina/química , Muramidasa/química , Adsorción , Cinética
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