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1.
Molecules ; 25(4)2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32079080

RESUMO

In the last decade, there has been growing interest in the food industry in replacing synthetic chemicals with natural products with bioactive properties. This study's aims were to determine the chemical composition and the antioxidant properties of the essential oil of Pastianica sylvestris. The essential oil was isolated with a yield of 0.41% (w/v) by steam distillation from the dried seeds and subsequently analysed by GC-MS. Octyl acetate (78.49%) and octyl hexanoate (6.68%) were the main components. The essential oil exhibited an excellent activity for the inhibition of primary and secondary oxidation products for cold-pressed sunflower oil comparable with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), which were evaluated using peroxide and thiobarbituric acid values. The antioxidant activity of the essential oil was additionally validated using DPPH radical scavenging (0.0016 ± 0.0885 mg/mL), and ß-carotene-linoleic acid bleaching assays. Also, the amounts of total phenol components (0.0053 ± 0.0023 mg GAE/g) were determined.


Assuntos
Acetatos/química , Antioxidantes/química , Óleos Voláteis/química , Pastinaca/química , Sementes/química , Acetatos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bioensaio , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Hidroxianisol Butilado/química , Hidroxianisol Butilado/isolamento & purificação , Hidroxitolueno Butilado/química , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/química , Óleos Voláteis/isolamento & purificação , Fenóis/química , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Óleo de Girassol/química , Tiobarbitúricos/química , beta Caroteno/química
2.
J Chromatogr A ; 1120(1-2): 244-51, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16513127

RESUMO

This study evaluated supercritical fluid extraction (SFE) combined with liquid chromatography-mass spectrometry (LC-MS) to determine trace preservatives and antioxidants including methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol (alpha-t) and alpha-tocopherol acetate (alpha-ta) in cosmetic products. A supercritical fluid extraction procedure was used to isolate four paraben preservatives and four antioxidants from the cosmetic matrix before quantitative analysis. The optimum extraction condition was performed with static extraction for 5 min, then dynamic extraction for 20 min by using carbon dioxide supercritical fluid at 14,000 kPa and 65 degrees C. Methanol was used as collection solvent and the sea sand was chosen as a filling material. The analytes were separated on a C18 reversed-phase column using methanol-water as mobile phase and quantified by measuring its mass spectrometry. The linearity range is from 10 to 20,000 ng/g with RSD values below 18%. Detection limits are achieved at the level of 4.7-142 ng/g. It was successfully applied to the determination of paraben preservatives and antioxidants in cosmetics without tedious pretreatment.


Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Cosméticos/análise , Conservantes Farmacêuticos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Antioxidantes/química , Antioxidantes/isolamento & purificação , Hidroxianisol Butilado/análise , Hidroxianisol Butilado/química , Hidroxianisol Butilado/isolamento & purificação , Hidroxitolueno Butilado/análise , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/isolamento & purificação , Cosméticos/química , Estrutura Molecular , Parabenos/análise , Parabenos/química , Parabenos/isolamento & purificação , Conservantes Farmacêuticos/química , Conservantes Farmacêuticos/isolamento & purificação , Pressão , Reprodutibilidade dos Testes , Temperatura
3.
J Chromatogr A ; 1074(1-2): 201-4, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15941056

RESUMO

A new and efficient method for the determination of antioxidants [Propyl gallate (PG), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT)] in cosmetics has been established by using micellar electrokinetic capillary chromatography with electrochemical detection (MECC-ED). Under the optimum conditions of the method, all analytes were successfully separated within 13 min at the separation voltage of 18 kV in a 20 mmol/L borate running buffer (pH 7.4) containing 25 mmol/L sodium dodecyl sulfate. The excellent linearity was obtained in the concentration range from 5.0 x 10(-4) to 2.0 x 10(-6) mol/L and the detection limits (S/N = 3) of PG, TBHQ, BHA, and BHT range from 3 x 10(-7) to 3 x 10(-6) mol/L.


Assuntos
Antioxidantes/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Cosméticos/química , Hidroxianisol Butilado/isolamento & purificação , Hidroxitolueno Butilado/isolamento & purificação , Eletroquímica , Concentração de Íons de Hidrogênio , Hidroquinonas/isolamento & purificação , Galato de Propila/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dodecilsulfato de Sódio
4.
J Med Chem ; 22(5): 569-71, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-458807

RESUMO

The title compound 1 was selectively synthesized in its pure isomeric form by means of the hydroxyl-protecting reagent dimethyl-tert-butylchlorosilane. Exclusive silylation occurred at the less hindered hydroxyl group of 3. Dimethyl sulfate methylation of 4 gave 5 in excellent yield. Compound 1 was then obtained by acid hydrolysis of 5. The two BHA isomers, 1 and 2, were tested on their inhibitory effects toward benzo[alpha]pyrene-induced neoplasia in the forestomach of the ICR/Ha mouse. Both isomers, when added to the diet, reduced the number of mice with tumors and the number of tumors per mouse. Isomer 1, which has the less hindered free hydroxyl group, showed higher inhibitory effect in the present experimental model.


Assuntos
Anisóis/síntese química , Hidroxianisol Butilado/síntese química , Carcinógenos/antagonistas & inibidores , Animais , Benzopirenos/antagonistas & inibidores , Benzopirenos/metabolismo , Hidroxianisol Butilado/isolamento & purificação , Hidroxianisol Butilado/farmacologia , Feminino , Isomerismo , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/prevenção & controle , Neoplasias Gástricas/induzido quimicamente , Neoplasias Gástricas/prevenção & controle
5.
J Food Sci ; 76(1): C98-103, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21535661

RESUMO

A cloud-point extraction (CPE) method using Triton X-114 (TX-114) nonionic surfactant was developed for the extraction and preconcentration of propyl gallate (PG), tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) from edible oils. The optimum conditions of CPE were 2.5% (v/v) TX-114, 0.5% (w/v) NaCl and 40 min equilibration time at 50 °C. The surfactant-rich phase was then analyzed by reversed-phase high-performance liquid chromatography with ultraviolet detection at 280 nm, using a gradient mobile phase consisting of methanol and 1.5% (v/v) acetic acid. Under the studied conditions, 4 synthetic phenolic antioxidants (SPAs) were successfully separated within 24 min. The limits of detection (LOD) were 1.9 ng mL(-1) for PG, 11 ng mL(-1) for TBHQ, 2.3 ng mL(-1) for BHA, and 5.9 ng mL(-1) for BHT. Recoveries of the SPAs spiked into edible oil were in the range 81% to 88%. The CPE method was shown to be potentially useful for the preconcentration of the target analytes, with a preconcentration factor of 14. Moreover, the method is simple, has high sensitivity, consumes much less solvent than traditional methods, and is environment-friendly. Practical Application: The method established in this article uses less organic solvent to extract SPAs from edible oils; it is simple, highly sensitive and results in no pollution to the environment.


Assuntos
Antioxidantes/análise , Antioxidantes/isolamento & purificação , Conservantes de Alimentos/análise , Conservantes de Alimentos/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Óleos de Plantas/química , Antioxidantes/química , Hidroxianisol Butilado/análise , Hidroxianisol Butilado/química , Hidroxianisol Butilado/isolamento & purificação , Hidroxitolueno Butilado/análise , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Conservantes de Alimentos/química , Química Verde , Hidroquinonas/análise , Hidroquinonas/química , Hidroquinonas/isolamento & purificação , Limite de Detecção , Octoxinol , Transição de Fase , Fenóis/química , Polietilenoglicóis/química , Galato de Propila/análise , Galato de Propila/química , Galato de Propila/isolamento & purificação , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Tensoativos/química
7.
Rev. iberoam. micol ; 31(2): 131-136, abr.-jun. 2014.
Artigo em Inglês | IBECS (Espanha) | ID: ibc-121254

RESUMO

Background. In the last years, food grade antioxidants are used safely as an alternative to traditional fungicides to control fungal growth in several food and agricultural products. Aims. In this work, the effect of butylated hydroxyanisole (BHA) and propyl paraben (PP) on two hydrolytic enzyme activity (β-d-glucosidase and α-d-galactosidase) by Aspergillus section Nigri species under different water activity conditions (aW; 0.98, 0.95 and 0.93) and incubation time intervals (24, 48, 72 and 96 h) was evaluated on peanut-based medium. Methods. The activity of two glycosidases, β-d-glucosidase and α-d-galactosidase, was assayed using as substrates 4-nitrophenyl-β-d-glucopyranosido and 4-nitrophenyl-α-d-galactopyranosido, respectively. The enzyme activity was determined by the increase in optical density at 405 nm caused by the liberation of p-nitrophenol by enzymatic hydrolysis of the substrate. Enzyme activity was expressed as micromoles of p-nitrophenol released per minute. Results. The major inhibition in β-d-glucosidase activity of A. carbonarius and A. niger was found with 20 mmol l−1 of BHA or PP at 0.98 and 0.95 aW, respectively, whereas for α-d-galactosidase activity a significant decrease in enzyme activity with respect to control was observed in A. carbonarius among 5 to 20 mmol l−1 of BHA or PP in all conditions assayed. Regarding A. niger, the highest percentages of enzyme inhibition activity were found with 20 mmol l−1 of BHA or PP at 0.95 aW and 96 h. Conclusions. The results of this work provide information about the capacity of BHA and PP to inhibit in vitro conditions two of the most important hydrolytic enzymes produced by A. carbonarius and A. niger species (AU)


Antecedentes. En los últimos años, para controlar el crecimiento fúngico, en lugar de los fungicidas tradicionales, tanto en la industria alimentaria como en los productos agrícolas se utilizan antioxidantes como aditivos alimentarios bien tolerados y sin riesgos de efectos adversos. Objetivos. En el presente estudio, en un medio de cultivo con cacahuete, se examinó el efecto de hidroxianisol butilado (BHA) y propilparabeno (PP) sobre la actividad de 2 enzimas hidrolíticas (β-d-glucosidasa y α-d-galactosidasa) producidas por especies de Aspergillus sección Nigri, en función de diferentes valores de actividad de agua del sustrato (aW; 0,98, 0,95 y 0,93) y tiempos de incubación (24, 48, 72 y 96 h). Métodos. La actividad de las 2 glucosidasas (β-d-glucosidasa y α-d-galactosidasa) se evaluó usando como sustrato 4-nitrofenil-β-d-glucopiranósido y 4-nitrofenil-α-d-galactopiranósido, respectivamente. La actividad enzimática se determinó mediante el aumento de la densidad óptica a 405 nm provocado por la liberación de p-nitrofenol, resultado de la hidrólisis enzimática del sustrato. La actividad enzimática se expresó como micromoles de p-nitrofenol liberado por minuto. Resultados. La mayor inhibición en la actividad de β-d-glucosidasa de Aspergillus carbonarius y Aspergillus niger se observó con 20 mmol l−1 de BHA o PP a 0,98 y 0,95 aW, respectivamente. Comparado con el control, en A. carbonarius se detectó una disminución significativa de la actividad de α-d-galactosidasa con 5-20 mmol l−1 de BHA o PP en todas las condiciones examinadas. Con respecto a A. niger, los porcentajes mas elevados de inhibición enzimática se observaron con 20 mmol l−1 de BHA o PP a 0,95 aW y un tiempo de incubación de 96 h. Conclusiones. Los resultados del presente estudio proporcionan información sobre la capacidad de BHA y PP para inhibir dos de las enzimas más importantes producidas por las especies A. carbonarius y A. niger (AU)


Assuntos
Aspergillus , Aspergillus/isolamento & purificação , Aspergillus niger , Aspergillus niger/isolamento & purificação , Aspergillus niger/patogenicidade , Hidroxianisol Butilado , Hidroxianisol Butilado/isolamento & purificação , Hidroxianisol Butilado/metabolismo , Enzimas/metabolismo , Antifúngicos/isolamento & purificação , Antifúngicos/metabolismo , Fungicidas Industriais/metabolismo
8.
Food Addit Contam ; 7(2): 223-33, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2354741

RESUMO

The reaction mixture and several products arising from the reaction of butylated hydroxyanisole (BHA) and nitrite in anaerobic aqueous acidic solution were separated and tested in the Salmonella mutagenicity test. Among the nine products separable by thin-layer chromatography, 1-hydroxyl-2-tert-butyl-4-methoxy-6-nitrobenzene (BHA-NO2), tert-butyl-substituted para-quinone (t-BuQ) and 3-tert-butyl-5-methoxy-1,2-benzoquinone (t-Bu-o-Q) are dominant. The last compound has not been previously reported in this system. Spot testing indicated at least one further compound of nitroso character and traces of tert-butylhydroquinone (t-BuHQ), which reacts with nitrite to yield t-BuQ. No evidence was found for the formation of the BHA dimer under our conditions. The substances gave no evidence of mutagenicity in the Salmonella typhimurium strains TA 98 and TA 100, either in the standard plate incorporation assay or in the procedure with preincubation with or without S9 mix. In some instances the substances were unstable in the test procedure.


Assuntos
Benzoquinonas , Hidroxianisol Butilado , Mutagênicos/isolamento & purificação , Nitritos , Hidroxianisol Butilado/isolamento & purificação , Hidroxianisol Butilado/farmacologia , Fenômenos Químicos , Química , Cromatografia em Camada Fina , Hidroquinonas/isolamento & purificação , Hidroquinonas/farmacologia , Testes de Mutagenicidade , Quinonas/isolamento & purificação , Quinonas/farmacologia
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