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1.
São Paulo; s.n; s.n; 2022. 87 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: biblio-1379165

RESUMEN

Um dos principais grupos de conservantes utilizados na maioria dos cosméticos são os parabenos que em muitos estudos demonstraram que podem provocar reações alérgicas como dermatite de contato, entre outras sensibilizações cutâneas. A fim de minimizar esses problemas, a indústria está produzindo cosméticos livres de conservantes ou de origem natural e em associações aos sintéticos. Dentre os conservantes naturais utilizados, podemos citar os óleos essenciais como uma alternativa viável. Diante deste contexto o presente trabalho visa avaliar experimentalmente o potencial antimicrobiano do óleo essencial de Conobea scoparioides Cham. & Schltdl., conhecida popularmente como pataqueira, o efeito de sua associação com parabenos e de sua eficácia como conservante em bases cosméticas. A composição do óleo essencial foi avaliada, indicando que este é composto em sua maior parte por terpenos, tendo éter metílico do timol (39,2%), timol (33,8 %) e α-felandreno (15,9%) como compostos majoritários. A atividade antimicrobiana do óleo essencial e do timol foi acessada através da concentração inibitória mínima (CIM), cujos resultados em µg/mL para o óleo essencial e o timol foram respectivamente: Staphylococcus aureus 650,70 e 284,90, Escherichia coli 721,53 e 271,20, Pseudomonas aeruginosa 1748,00 e > 2.000, Burkholderia cepacia 833,03 e 1.077,70, Candida albicans 521,43 e 172,61 e Aspergillus brasiliensis 300 e 400. O efeito sinérgico da associação do óleo essencial com os parabenos foi realizado através de um delineamento experimental centroide simplex para uma mistura de metilparabeno, propilparabeno e óleo essencial frente aos mesmos micro-organismos utilizados na determinação da atividade antimicrobiana. As concentrações ideais obtidas pela análise estatística para cada componente em µg/mL foram: 1120 para o metilparabeno, 350 para o propilparabeno e 675 para o óleo essencial. O teste de eficácia do sistema conservante em formulação cosmética foi efetuado empregando as concentrações ideais e mais duas concentrações superiores e uma abaixo do ideal. Para todas as cepas microbianas desafiadas o resultado do teste foi de redução total da carga microbiana inoculada nos sete dias de ensaio e nenhum aumento até o vigésimo oitavo dia o que demonstra a eficácia da associação do óleo essencial com os conservantes sintéticos. O óleo essencial de C. scoparioides apresentou um potencial antimicrobiano importante tanto sozinho como em associação com conservantes sintéticos. Estes resultados sugerem que esse óleo pode ser usado para compor um sistema conservante para formulações cosméticas contendo uma menor quantidade de sintéticos


One of the main groups of preservatives used in most cosmetics are parabens, that many studies have shown that they can cause allergic reactions such as contact dermatitis, among other skin sensitizations. To minimize these problems, the industry is producing cosmetics preservative free or using natural products instead and their combination with the synthetics. Among the natural preservatives used, we can mention essential oils as a viable alternative. In this context, the present work aims to experimentally evaluate the antimicrobial potential of the Conobea scoparioides Cham. & Schltdl. essential oil, popularly known as pataqueira, the effect of its association with parabens and its effectiveness as a preservative in cosmetic bases. The essential oil composition was analyzed, indicating that it is composed mostly of terpenes, with thymol methyl ether (39.2%), thymol (33.8%) and -phelandrene (15.9%) as major compounds. The antimicrobial activity of essential oil and thymol was accessed through the minimum inhibitory concentration (MIC), whose results in µg/mL for essential oil and thymol were respectively: Staphylococcus aureus 650.70 and 284.90, Escherichia coli 721, 53 and 271.20, Pseudomonas aeruginosa 1748.00 and > 2,000, Burkholderia cepacia 833.03 and 1,077.70, Candida albicans 521.43 and 172.61 and Aspergillus brasiliensis 300 and 400. The synergistic effect of the association of essential oil with parabens was performed through a centroid simplex experimental design for a mixture of methylparaben, propylparaben and essential oil against the same microorganisms used in the antimicrobial activity evaluation The ideal concentrations obtained by statistical analysis for each component in µg/mL were: 1120 for methylparaben, 350 for propylparaben and 675 for essential oil. The effectiveness test of the preservative system in cosmetic formulation was carried out using the ideal concentrations plus two higher concentrations and one below the ideal. For all challenged microbial strains, the test result was a total reduction of the inoculated microbial load in the seven days of testing and no increase until the twenty-eighth day, which demonstrates the effectiveness of the association of essential oil with synthetic preservatives. C. scoparioides essential oil showed an important antimicrobial potential both alone and in association with parabens. These results demonstrated that it can be used to compose a preservative system for cosmetic formulations containing lower amounts of synthetics


Asunto(s)
Aspergillus/clasificación , Aceites Volátiles/análisis , Cosméticos , Plantaginaceae/clasificación , Parabenos/farmacología , Piel , Burkholderia cepacia/clasificación , Aditivos para Cosméticos , Antiinfecciosos/efectos adversos
2.
Environmental Health and Toxicology ; : e2018018-2018.
Artículo en Inglés | WPRIM | ID: wpr-719129

RESUMEN

The objective of this study was to determine toxicities of four parabens (methyl paraben, MP; ethyl paraben, EP; n-propyl paraben, PP; and n-butyl paraben; BP) and their mixtures to two aquatic microorganisms, Daphnia magna and Aliivibrio fischeri. Parabens are one of the widely used preservatives for personal care products, such as cosmetics, pharmaceuticals and food also. First, each paraben was treated to D. magna to measure the toxicity levels as LC₂₀ and LC₅₀. The results showed their value of MP (25.2 mg/L, 73.4 mg/L), EP (18.4 mg/L, 43.7 mg/L), PP (10.4 mg/L, 21.1 mg/L) and BP (3.3 mg/L, 11.2 mg/L). Then, each of the parabens was treated to A. fischeri and calculated their EC₂₀ and EC₅₀ by bioluminescence inhibition test. The results showed the values of MP (2.93 mg/L, 16.8 mg/L), EP (1.18 mg/L, 6.74 mg/L), PP (0.51 mg/L, 5.85 mg/L) and BP (0.21 mg/L, 2.34 mg/L). These four parabens belong to the group classified as being ‘harmful to aquatic organisms’ (above 10 mg/L, below 100 mg/L). After measuring the toxicity, EC₂₀ values of two or more parabens were tested in order to investigate their toxicity. A total of ten combinations of four parabens were tested. As a result, the bioluminescence inhibition test of A. fischeri showed that the toxicity of mixture parabens was stronger than that of a single compound and combinations of three parabens showed the highest bioluminescence inhibition. These results showed that independent toxicity of paraben was maintained. Therefore, it can be predictable that the toxicity of paraben is getting stronger by the addition of other parabens.


Asunto(s)
Humanos , Aliivibrio fischeri , Aliivibrio , Daphnia , Parabenos
3.
Environmental Health and Toxicology ; : 2018018-2018.
Artículo en Inglés | WPRIM | ID: wpr-786757

RESUMEN

The objective of this study was to determine toxicities of four parabens (methyl paraben, MP; ethyl paraben, EP; n-propyl paraben, PP; and n-butyl paraben; BP) and their mixtures to two aquatic microorganisms, Daphnia magna and Aliivibrio fischeri. Parabens are one of the widely used preservatives for personal care products, such as cosmetics, pharmaceuticals and food also. First, each paraben was treated to D. magna to measure the toxicity levels as LC₂₀ and LC₅₀. The results showed their value of MP (25.2 mg/L, 73.4 mg/L), EP (18.4 mg/L, 43.7 mg/L), PP (10.4 mg/L, 21.1 mg/L) and BP (3.3 mg/L, 11.2 mg/L). Then, each of the parabens was treated to A. fischeri and calculated their EC₂₀ and EC₅₀ by bioluminescence inhibition test. The results showed the values of MP (2.93 mg/L, 16.8 mg/L), EP (1.18 mg/L, 6.74 mg/L), PP (0.51 mg/L, 5.85 mg/L) and BP (0.21 mg/L, 2.34 mg/L). These four parabens belong to the group classified as being ‘harmful to aquatic organisms’ (above 10 mg/L, below 100 mg/L). After measuring the toxicity, EC₂₀ values of two or more parabens were tested in order to investigate their toxicity. A total of ten combinations of four parabens were tested. As a result, the bioluminescence inhibition test of A. fischeri showed that the toxicity of mixture parabens was stronger than that of a single compound and combinations of three parabens showed the highest bioluminescence inhibition. These results showed that independent toxicity of paraben was maintained. Therefore, it can be predictable that the toxicity of paraben is getting stronger by the addition of other parabens.


Asunto(s)
Humanos , Aliivibrio fischeri , Aliivibrio , Daphnia , Parabenos
4.
An. acad. bras. ciênc ; 89(2): 789-797, Apr.-June 2017. graf
Artículo en Inglés | LILACS | ID: biblio-886693

RESUMEN

ABSTRACT This study aims to identify special metabolites in polar extracts from Urochloa humidicola (synonym Brachiaria humidicola) that have allelopathic effects and induce secondary photosensitization in ruminants. The compounds were isolated and identified via chromatographic and spectroscopic techniques. The compounds 4-hydroxy-3-methoxy-benzoic acid, trans-4-hydroxycinnamic acid, and p-hydroxy-benzoic acid; the flavonols isorhamnetin-3-O-β-d-glucopyranoside and methyl quercetin-3-O-β-d-glucuronate; and kaempferitrin, quercetin-3-O-α-l-rhamnopyranoside, and tricin were identified in the extract from the leaves of Urochloa humidicola. Two furostanic saponins, namely, dioscin and 3-O-α-l-rhamnopyranosyl-(1-4)-[α-l-rhamnopyranosyl-(1-2)]-β-d-glucopyranosyl-penogenin, as well as catechin-7-O-β-d-glucopyranoside were identified in the methanolic extract obtained from the roots of this plant. This species features a range of metabolites that may be toxic for animals if used in food and may interfere with the growth medium, thereby inhibiting the development of other species.


Asunto(s)
Flavonoides/aislamiento & purificación , Extractos Vegetales/química , Brachiaria/química , Parabenos/aislamiento & purificación , Parabenos/química , Saponinas/química , Ácido Vanílico/química , Flavonoides/química , Crotonatos/aislamiento & purificación , Crotonatos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Cromatografía en Capa Delgada , Glicósidos/aislamiento & purificación , Glicósidos/química
5.
Journal of Korean Academy of Oral Health ; : 154-161, 2017.
Artículo en Coreano | WPRIM | ID: wpr-194227

RESUMEN

OBJECTIVES: The purpose of this study was to investigate changes in public recognition of parabens on Twitter and the research status of parabens related to toothpaste. METHODS: Tweet information between 2010 and October 2016 was collected by an automatic web crawler and examined according to tweet frequency, key words (2012-October 2016), and issue tweet detection analyses to reveal changes in public recognition of parabens on Twitter. To investigate the research status of parabens related to toothpaste, queries such as “paraben,”“paraben and toxicity,”“paraben and (toothpastes or dentifrices),” and “paraben and (toothpastes or dentifrices) and toxicity” were used. RESULTS: The number of tweets concerning parabens sharply increased when parabens in toothpaste emerged as a social issue (October 2014), and decreased from 2015 onward. However, toothpaste and its related terms were continuously included in the core key words extracted from tweets from 2015. They were not included in key words before 2014, indicating that the emergence of parabens in toothpaste as a social issue plays an important role in public recognition of parabens in toothpaste. The issue tweet analysis also confirmed the change in public recognition of parabens in toothpaste. Despite the expansion of public recognition of parabens in toothpaste, there are only seven research articles on the topic in PubMed. CONCLUSIONS: The general public clearly recognized parabens in toothpaste after emergence of parabens in toothpaste as a social issue. Nevertheless, the scientific information on parabens in toothpaste is very limited, suggesting that the efforts of dental scientists are required to expand scientific knowledge related to parabens in oral hygiene measures.


Asunto(s)
Higiene Bucal , Parabenos , Pastas de Dientes
6.
Chinese Journal of Biotechnology ; (12): 328-337, 2015.
Artículo en Chino | WPRIM | ID: wpr-240640

RESUMEN

4-Hydroxybenzoate (4HBA) is an important chemical compound used for synthesis of liquid crystal. Production of 4HBA from renewable resources is an effective mean to solve problems such as environmental pollution and petroleum shortage. This review briefly introduces the chemical synthesis of 4HBA from oil compounds, and mainly describes the progress in 4HBA biosynthesis from renewable resources by plants and microorganisms. In most intriguing aspect of plant-based synthesis of 4HBA is the appeal of directly synthesizing a chemical from CO2. However, the glucosylation system in plant cells converting 4HBA to glucose conjugates, causing the post treatment a problem. The recombinant microorganisms produce pure 4HBA, but less efficient. A new strain of Microbulbifer has ability to naturally accumulate 4HBA from glucose. Elucidation of the metabolic pathways and regulation systems would improve 4HBA synthesis efficiency.


Asunto(s)
Alteromonadaceae , Metabolismo , Glucosa , Química , Glicosilación , Microbiología Industrial , Redes y Vías Metabólicas , Parabenos , Metabolismo , Plantas , Metabolismo
7.
Biomedical and Environmental Sciences ; (12): 85-96, 2014.
Artículo en Inglés | WPRIM | ID: wpr-247080

RESUMEN

<p><b>OBJECTIVE</b>To evaluate the influence of an extract of Genista tinctoria L. herba (GT) or methylparaben (MP) on histopathological changes and 2 biomarkers of oxidative stress in rats subchronicly exposed to bisphenol A (BPA).</p><p><b>METHODS</b>Adult female Wistar rats were orally exposed for 90 d to BPA (50 mg/kg), BPA+GT (35 mg isoflavones/kg) or BPA+MP (250 mg/kg). Plasma and tissue samples were taken from liver, kidney, thyroid, uterus, ovary, and mammary gland after 30, 60, and 90 d of exposure respectively. Lipid peroxidation and in vivo hydroxyl radical production were evaluated by histological analysis along with malondialdehyde and 2,3-dihydroxybenzoic acid detection.</p><p><b>RESULTS</b>The severity of histopathological changes in liver and kidneys was lower after GT treatment than after BPA or BPA+MP treatment. A minimal thyroid receptor antagonist effect was only observed after BPA+MP treatment. The abnormal folliculogenesis increased in a time-dependent manner, and the number of corpus luteum decreased. No significant histological alterations were found in the uterus. The mammary gland displayed specific estrogen stimulation changes at all periods. Both MP and GT revealed antioxidant properties reducing lipid peroxidation and BPA-induced hydroxyl radical generation.</p><p><b>CONCLUSION</b>GT L. extract ameliorates the toxic effects of BPA and is proved to have antioxidant potential and antitoxic effect. MP has antioxidant properties, but has either no effect or exacerbates the BPA-induced histopathological changes.</p>


Asunto(s)
Animales , Femenino , Ratas , Compuestos de Bencidrilo , Toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas , Patología , Disruptores Endocrinos , Toxicidad , Genista , Radical Hidroxilo , Sangre , Peroxidación de Lípido , Hígado , Patología , Estrés Oxidativo , Parabenos , Toxicidad , Fenoles , Toxicidad , Fitoterapia , Extractos Vegetales , Farmacología , Usos Terapéuticos , Ratas Wistar
8.
J. appl. oral sci ; 20(4): 444-448, July-Aug. 2012. ilus
Artículo en Inglés | LILACS | ID: lil-650621

RESUMEN

OBJECTIVE: To detect the presence and concentration of methylparaben in cartridges of commercial Brazilian local anesthetics. MATERIAL AND METHODS: Twelve commercial brands (4 in glass and 8 in plastic cartridges) of local anesthetic solutions for use in dentistry were purchased from the Brazilian market and analyzed. Different lots of the commercial brands were obtained in different Brazilian cities (Piracicaba, Campinas and São Paulo). Separation was performed using high performance liquid chromatography (HPLC) with UV-Vis detector. The mobile phase used was acetonitrile:water (75:25 - v/v), pH 4.5, adjusted with acetic acid at a flow rate of 1.0 ml.min-1. RESULTS: When detected in the solutions, the methylparaben concentration ranged from 0.01% (m/v) to 0.16% (m/v). One glass and all plastic cartridges presented methylparaben. CONCLUSION: 1. Methylparaben concentration varied among solutions from different manufacturers, and it was not indicated in the drug package inserts; 2. Since the presence of methylparaben in dental anesthetics is not regulated by the Brazilian National Health Surveillance Agency (ANVISA) and this substance could cause allergic reactions, it is important to alert dentists about its possible presence.


Asunto(s)
Humanos , Anestésicos Locales/química , Parabenos/análisis , Conservadores Farmacéuticos/análisis , Ácido Acético/química , Acetonitrilos/química , Brasil , Hipersensibilidad a las Drogas/etiología , Indicadores y Reactivos/química , Soluciones/química , Factores de Tiempo
9.
Braz. j. pharm. sci ; 47(4): 779-785, Oct.-Dec. 2011. graf, tab
Artículo en Inglés | LILACS | ID: lil-618071

RESUMEN

Parabens, common food preservatives, were analysed by capillary electrochromatography, using a commercial C18 silica (3 µm, 40 cm × 100 µm i. d.) capillary column as separation phase. In order to optimise the separation of these preservatives, the effects of mobile phase composition on the separation were evaluated, as well as the applied voltage and injection conditions. The retention behavior of these analytes was strongly influenced by the level of acetonitrile in the mobile phase. An optimal separation of the parabens was obtained within 18.5 minutes with a pH 8.0 mobile phase composed of 50:50 v/v tris(hydroxymethyl)aminomethane buffer and acetonitrile. The method was successfully applied to the quantitative analysis of paraben preservatives in sweetener samples with direct injection.


Os parabenos, empregados como conservantes em alimentos, foram analisados por eletrocromatografia capilar, empregando uma coluna comercial recheada com partículas de sílica-C18 (3 µm, 40 cm × 100 µm d. i.) como fase estacionária de separação. Para otimizar a separação destes conservantes foram avaliados os efeitos da composição da fase móvel na separação, bem como a voltagem e as condições de injeção. O comportamento de retenção dos analitos foi fortemente influenciado pela proporção de acetonitrila na fase móvel. A separação dos parabenos foi alcançada em 18,5 min com uma fase móvel contendo tampão tris(hidroximetil)aminometano e acetonitrila na proporção 50:50 v/v. O método foi aplicado na análise quantitativa de parabenos em adoçantes empregando a injeção direta das amostras.


Asunto(s)
Parabenos/análisis , Electrocromatografía Capilar/métodos , Edulcorantes/farmacocinética , /análisis
10.
Acta Pharmaceutica Sinica ; (12): 188-192, 2011.
Artículo en Chino | WPRIM | ID: wpr-348978

RESUMEN

To study the chemical constituents of Asarum himalaicum, fifteen compounds were isolated from a 70% ethanol extract by using a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and semi-preparative HPLC. By spectroscopic techniques including 1H NMR, 13C NMR, and HR-ESI-MS, these compounds were identified as 4-demethoxyaristolochic acid BII (1), aristolochic acid I (2), aristolochic acid Ia (3), 7-hydroxyaristolochic acid I (4), aristolochic acid IV (5), aristolic acid II (6), debilic acid (7), aristololactam I (8), 9-hydroxyaristololactam I (9), 7-methoxyaristololactam IV (10), (2S)-narigenin-5, 7-di-O-beta-D-pyranosylglucoside (11), 4-hydroxybenzoic acid (12), 3, 4-dihydroxybenzoic acid (13), 4-hydroxycinnamic acid (14), and beta-sitosterol (15). All of these compounds (1-15) were obtained from A. himalaicum for the first time. Among them, 1 was identified as a new compound, and compounds 3-6, 9, 12-14 were isolated from Asarum genus for the first time. Since the kidney toxicity of aristolochic acids and aristololactams has been reported, the result of this investigation suggests that it should be cautioned to use A. himalaicum as a medicine.


Asunto(s)
Ácidos Aristolóquicos , Química , Asarum , Química , Cromatografía Líquida de Alta Presión , Ácidos Cumáricos , Química , Hidroxibenzoatos , Química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Parabenos , Química , Plantas Medicinales , Química , Propionatos , Sitoesteroles , Química , Espectrometría de Masa por Ionización de Electrospray
11.
Hanyang Medical Reviews ; : 261-268, 2011.
Artículo en Coreano | WPRIM | ID: wpr-122151

RESUMEN

Many different additives include preservatives, stabilizers, conditioners, thickeners, colorings, flavorings, sweeteners, and antioxidants. Despite the multitude of additives known, only a small number has been associated with hypersensitivity reactions. A number of investigators have suggested that a significant population of patients with allergic diseases has symptoms related to the ingestion of food additives. However, the incidence and mechanism of reactions to additives in patients with chronic urticaria, angioedema, and atopic dermatitis remain unknown. A few studies of monosodium glutamate is reported to be associated with atopic dermatitis, but their relationship remains unknown. The best known dye is tartrazine. The group of azo dyes includes ponceau and sunset yellow. Amaranth (FD&C red no. 5) was banned from use in the US in 1975 because of claims related to carcinogenicity. Most of them are reported to be associated with aggravation of atopic dermatitis. Parabens are aliphatic esters of parahydroxybenzoic acid. Sodium benzoate is a closely related substance usually reported to cross-react with these compounds. These agents, which are widely used as preservatives in both food and drugs, are well recognized as causes of severe contact dermatitis. Additives would have to act as haptens to create a response mediated by IgE. The majority of these reactions are not of the immediate hypersensitivity type. Many cases of additive-provoked urticaria or dermatitis occur as late as 24 hours after challenge, arguing against an IgE-mediated mechanism. In conclusion, the exact relationship between food additives and the allergic diseases still remains to be solved.


Asunto(s)
Humanos , Angioedema , Antioxidantes , Compuestos Azo , Colorantes , Dermatitis , Dermatitis Atópica , Dermatitis por Contacto , Ingestión de Alimentos , Ésteres , Aditivos Alimentarios , Hipersensibilidad a los Alimentos , Haptenos , Hipersensibilidad , Hipersensibilidad Inmediata , Inmunoglobulina E , Incidencia , Parabenos , Investigadores , Benzoato de Sodio , Glutamato de Sodio , Edulcorantes , Tartrazina , Urticaria
12.
China Journal of Chinese Materia Medica ; (24): 1024-1027, 2011.
Artículo en Chino | WPRIM | ID: wpr-252950

RESUMEN

<p><b>OBJECTIVE</b>To investigate the chemical constituents of the branches and leaves of Polyalthia nemoralis.</p><p><b>METHOD</b>The compounds were isolated and purified by silica gel, macroporous adsorption resin and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.</p><p><b>RESULT</b>Fourteen compounds were isolated and identified as syringic acid (1), 3-methoxy-4-hydroxycinnamic acid (2), vanillic acid (3), 4-hydroxybenzoic acid (4), mauritianin (5), (+)-xylopinidine (6), (+)-oblongine(7), (+)-tembetarine (8), eythritol (9), D-mannitol (10), ethyl-beta-D-glucopyranoside (11), (+)-magnoflorine (12), stepharanine (13), (2S, 4R)-4-hydroxy-2-piperidine-carboxylic acid (14), respectively.</p><p><b>CONCLUSION</b>All the compounds were isolated from the genus Polyalthia for the first time; compounds 6 and 13 showed inhibitation activities against multi tumor cell lines.</p>


Asunto(s)
Humanos , Alcaloides , Química , Farmacología , Antineoplásicos Fitogénicos , Química , Farmacología , Aporfinas , Química , Farmacología , Línea Celular Tumoral , Supervivencia Celular , Cromatografía en Agarosa , Métodos , Ácidos Cumáricos , Química , Farmacología , Ácido Gálico , Química , Farmacología , Quempferoles , Química , Farmacología , Parabenos , Química , Farmacología , Extractos Vegetales , Química , Farmacología , Hojas de la Planta , Química , Tallos de la Planta , Química , Polyalthia , Química , Ácido Vanílico , Química , Farmacología
13.
RGO (Porto Alegre) ; 58(1): 17-20, jan.-mar. 2010. tab
Artículo en Inglés | LILACS, BBO | ID: biblio-873915

RESUMEN

Objective: To evaluate whether methylparaben and propylparaben, which present a similar chemical structure, increase fluoride uptake by demineralized dental enamel when present in buffered solutions. Methods: The study comprised an in vitro experiment using blocks of bovine dental enamel with artificial carious lesions. Enamel blocks were exposed to the following treatment (n=12): fluoride solution (200 ppm fluoride) - control; solution containing fluoride and 13 mM methylparaben; solution containing fluoride and 13 mM propylparaben in 35% propylene glycol; solution containing fluoride in 35% propylene glycol. All solutions were buffered (0.01 M cacodilate) and the pH was adjusted to 6.27. The blocks were exposed to the treatment solutions in the proportion of 2 ml per mm2 of exposed enamel area and fluoride formed was estimated after removing an enamel layer by acid etching. Fluoride extracted was determined by ion specific electrode and the amount of enamel removed was estimated by phosphorus analysis. ANOVA followed by Tukey's test were used for statistical analysis, with significance level at 5%. Results: The dental blocks of treatment groups containing both parabens and the control group presented similar fluoride concentration in enamel and no statistical difference was observed among them (p>0.05). The dental blocks of treatment group containing fluoride and propylene glycol showed the lowest value of fluoride present in enamel, which was significantly different from the control and fluoride and methylparaben groups (p<0.05). Conclusion: Methyl and propylparaben in a buffered solution do not enhance fluoride uptake by demineralized dental enamel.


Objetivo: Avaliar se o metilparabeno e o propilparabeno, os quais apresentam uma estrutura química similar, aumentam a incorporaçãode fluoreto pelo esmalte dental desmineralizado quando presentes em soluções tamponadas. Métodos: O estudo envolveu um ensaio in vitro, com 48 blocos de esmalte dental bovino com lesão cariosa artificial. Os blocos de esmalte, 12 para cada grupo, foram expostos aos seguintes tratamentos: grupo 1 (controle), solução de fluoreto (200 ppm F), Grupo 2, solução contendo fluoreto e metilparabeno 13 mM; Grupo 3 solução contendo fluoreto e propilparabeno 13 mM em propilenoglicol 35% e Grupo 4, solução contendo fluoreto em propilenoglicol 35%. Todas as soluções foram tamponadas (cacodilato 0,01 M) e o pH ajustado para 6,27. Os blocos foram expostos a soluções de tratamento na proporção de 2 ml por mm2 da área de esmalte exposta e fluoreto formado foi estimado após remoção de uma camada de esmalte por ataque ácido. Flúor extraído foi determinado por eletrodo específico e a quantidade de esmalte removido foi estimada pela análise de fósforo. Análise de variância seguida do teste de Tukey foi usada para análise estatística, com nível de significância de 5%. Resultados: Os blocos dentais dos grupos de tratamento contendo ambos parabenos e do grupo controle apresentaram concentrações de flúor similar no esmalte e nenhuma diferença estatística entre eles foi observada (p>0,05). Os blocos dentais do grupo de tratamento contendo fluoreto e propilenoglicol mostraram o valor mais baixo de flúor presente no esmalte, o qual foi significantemente diferente daquele dos grupos controle e flúor e metilparabeno (p<0,05). Conclusão: Metilparabeno e propilparabeno em uma solução tamponada não aumentam a incorporação de flúor pelo esmalte dental desmineralizado.


Asunto(s)
Animales , Bovinos , Caries Dental , Esmalte Dental , Fluoruros/farmacología , Parabenos/farmacología , Técnicas In Vitro
14.
Acta Pharmaceutica Sinica ; (12): 874-878, 2010.
Artículo en Chino | WPRIM | ID: wpr-354561

RESUMEN

To study the chemical constituents of Drynariae Rhizoma, nine phenolic acids were isolated from a 70% ethanol extract by using a combination of various chromatographic techniques including column chromatography over silica gel, ODS, Sephadex LH-20, and semi-preparative HPLC. By spectroscopic techniques including 1H NMR, 13C NMR, 2D NMR, and HR-ESI-MS, these compounds were identified as 4, 4'-dihydroxy-3, 3'-imino-di-benzoic acid (1), protocatechuic acid (2), gallic acid (3), p-hydroxybenzoic acid (4), (E)-caffeic acid (5), ethyl trans-3, 4-dihydroxycinnamate (6), caffeic acid 4-O-beta-D-glucopyranoside (7), p-coumaric acid 4-O-beta-D-glucopyranoside (8), and 23(S)-12-O-caffeoyl-12-hydroxyllauric acid glycerol ester (9), separately. Among them, 1 and 9 are new compounds, and 3, 4, and 6 were isolated from Drynaria species for the first time.


Asunto(s)
Benzoatos , Química , Ácidos Cafeicos , Química , Cinamatos , Química , Ácido Gálico , Química , Glicerol , Química , Hidroxibenzoatos , Química , Iminas , Química , Ácidos Láuricos , Química , Conformación Molecular , Estructura Molecular , Parabenos , Química , Plantas Medicinales , Química , Polypodiaceae , Química , Rizoma , Química
15.
Acta Pharmaceutica Sinica ; (12): 32-37, 2009.
Artículo en Chino | WPRIM | ID: wpr-232602

RESUMEN

This study is to investigate the activation effect of butyl-p-hydroxybenzoate (Bpb) on cAMP-dependent cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel gating. A stably transfected Fischer rat thyroid (FRT) epithelial cell lines co-expressing human CFTR and a green fluorescent protein mutant with ultra-high halide sensitivity (EYFP) were used to measure CFTR-mediated iodide influx rates. Bpb was identified as an effective activator of wild-type CFTR chloride channel, it can correct delta F508-CFTR gating defects but not processing defect. Bpb can't potentiate G551D-CFTR channel gating. The activity was reversible and dose-dependent. The study also provided clues that Bpb activates CFTR chloride channel through a direct binding mechanism. Our study identified Bpb as a novel structure CFTR activator. Bpb may be useful for probing CFTR channel gating mechanisms and as a lead compound to develop pharmacological therapy for CFTR-related disease.


Asunto(s)
Animales , Ratas , Línea Celular , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Genética , Metabolismo , Relación Dosis-Respuesta a Droga , Células Epiteliales , Metabolismo , Proteínas Fluorescentes Verdes , Genética , Metabolismo , Activación del Canal Iónico , Mutación , Parabenos , Farmacología , Ratas Endogámicas F344 , Glándula Tiroides , Biología Celular
16.
Hamdard Medicus. 2008; 51 (4): 111-117
en Inglés | IMEMR | ID: emr-99743

RESUMEN

Shampoos are products which remove surface grease and dirt from the hair shaft and scalp. The cleansing or detergent action of a shampoo is a primary function. However, foaming characteristic of a shampoo has an important role in its acceptability. Often alkanolamides have been used for accessed stable foam; but because of producing nitrosamines, they are potentially carcinogenic compounds. So, the main goal of this research was elimination of these materials from shampoo formula. A. squarrosum is one of the 23 species of the genus Acanthophyllum endemic in Iran. Due to the presence of saponin in its root, chubak, has been used traditionally as a detergent. In this study, total saponin of Acanthophyllum squarrosum roots was extracted using several solvents. A clear liquid shampoo base was formulated using Texapon as surfactant, sodium chloride as thickener, glycerin as hair conditioner, methyl paraben as preservative and EDTA as sequestering agent. Then, a definite amount of Texapon was substituted by 1, 2.5 and 5 percent of total herbal saponin. The evaluation of foaming ability by Ross-Miles method and cleansing power by Thompson test showed the best result with the formula containing 20% Texapon and 5% total herbal saponin. So it was selected as the best formula and evaluated for other characteristics. In addition to possessing the properties of a liquid shampoo, the unique characteristics of the formula containing 5% total herbal saponin produced stable foam without using foam stabilizers. Evaluation of cleansing power by Thompson test, determined that final formula is a shampoo for normal hair with very good cleansing ability. Rheological studies showed that final formula had pseudoplastic behaviour, Organoleptic and physicochemical characteristics of final formula were in the acceptable range


Asunto(s)
Preparaciones para el Cabello , Dodecil Sulfato de Sodio , Preparaciones de Plantas , Cloruro de Sodio , Ácido Oleanólico , Glicerol , Parabenos , Ácido Edético
17.
ACES-Actualites Cliniques et Scientifiques. 2008; 26 (2): 130-134
en Francés | IMEMR | ID: emr-85577

RESUMEN

The aim of this article is to form the criteria of choice of the anesthetic solution according to the adjuvants added to this solution. After reviewing the composition of the anesthetic solution, the anesthetic molecules are listed and the additives which can be added to theses molecules such as vasoconstrictors, parabens, sulfites and EDTA, are studied and detailed with their dosages. Finally, an example is presented to show how to choose a solution between many specialties of the same molecule, but with many adjuvant and different dosages


Asunto(s)
Anestésicos Locales , Adyuvantes Anestésicos , Vasoconstrictores , Parabenos , Sulfitos , Ácido Edético
18.
China Journal of Chinese Materia Medica ; (24): 1847-1848, 2008.
Artículo en Chino | WPRIM | ID: wpr-252211

RESUMEN

<p><b>OBJECTIVE</b>To study the chemical constituents of Dendobium crystallinum.</p><p><b>METHOD</b>Compounds were isolated and purified by silica gel and Sephadex LH-20 column chromatography. Their structures were identified by physicochemical properties and spectral analyses.</p><p><b>RESULT</b>Nine compounds were obtained and identified as: 4, 4'-dihydroxy-3, 5-dimethoxybi-benzyl (1), gigantol (2), naringenin (3) , p-hydroxybenzoic acid (4), n-tetracosyl trans-p-cou-marate (5), n-octacosy trans-p-coumarate (6), n-hexacosyl trans-ferulate (7), stigmasterol (8), daucosterol (9).</p><p><b>CONCLUSION</b>All these compounds were obtained from this plant for the first time, compounds 1 and 4 were isolated firstly from the genus.</p>


Asunto(s)
Bibencilos , Cromatografía , Dendrobium , Química , Medicamentos Herbarios Chinos , Química , Flavanonas , Química , Guayacol , Química , Espectroscopía de Resonancia Magnética , Parabenos , Química , Sitoesteroles , Química , Estigmasterol , Química
19.
China Journal of Chinese Materia Medica ; (24): 517-521, 2008.
Artículo en Chino | WPRIM | ID: wpr-284454

RESUMEN

<p><b>OBJECTIVE</b>To study the chemical constituents in roots of Caragana sinica.</p><p><b>METHOD</b>The constituents were isolated by silica gel column chromatography, and their structures were identified by spectroscopic methods.</p><p><b>RESULT</b>Seven compounds were identified as (+) - stenophyllol B (1), 4-hydroxybenzoic acid (2), odoratin (3), resveratrol (4), cararosinol A (5), leachinol C (6), carasinaurone (7) respectively.</p><p><b>CONCLUSION</b>Compound 1 was a new compound which was the enantiomer of stenophyllol B. Compounds 2-6 were obtained from the plant for the first time.</p>


Asunto(s)
Caragana , Química , Cromatografía en Gel , Medicamentos Herbarios Chinos , Química , Estructura Molecular , Parabenos , Química , Raíces de Plantas , Química , Estilbenos , Química
20.
Pakistan Journal of Pharmaceutical Sciences. 2007; 20 (2): 100-106
en Inglés | IMEMR | ID: emr-84716

RESUMEN

A rapid and sensitive reverse phase high performance liquid chromatographic [RP-HPLC] method for the analysis of levofloxacin from bulk materials, dosage formulations and human serum is described. This isocratic method employs, a Nucleosil, C18 [10um, 25 cm x 0.46 cm] column with a mobile phase of water and acetonitrile [6:5], where in phosphoric acid was used to adjust the pH to 2.9 and propylparaben as an internal standard. Optimization of levofloxacin analysis was carried out using multivariate calibration technique and detector response was recorded at five different wave lengths. A linear response [r > 0.9999] was observed in the range of 40 to 10000 ng ml-1. The method shows good recoveries, intra and inter-day relative standard deviations were less than 1.2%. Validation parameters as specificity, accuracy and robustness were also determined. The method can conveniently be used for analysis of levofloxacin pharmacokinetic levels in human serum and pharmaceutical formulations


Asunto(s)
Cromatografía Líquida de Alta Presión , Análisis Multivariante , Química Farmacéutica , Parabenos
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