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1.
Biomolecules ; 10(5)2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384801

RESUMO

Brazilian red propolis has been proposed as a new source of compounds with cytotoxic activity. Red propolis is a resinous material of vegetal origin, synthesized from the bees of the Appis mellifera family, with recognized biological properties. To obtain actives of low polarity and high cytotoxic profile from red propolis, in this work, we proposed a new solvent accelerated extraction method. A complete 23 factorial design was carried out to evaluate the influence of the independent variables or factors (e.g., temperature, number of cycles, and extraction time) on the dependent variable or response (i.e., yield of production). The extracts were analyzed by gas chromatography coupled with mass spectrometry for the identification of chemical compounds. Gas chromatography analysis revealed the presence of hydrocarbons, alcohols, ketones, ethers, and terpenes, such as lupeol, lupenone, and lupeol acetate, in most of the obtained extracts. To evaluate the cytotoxicity profile of the obtained bioactives, the 3-(4,5-dimethyl-2-thiazole)-2,5-diphenyl-2-H-tetrazolium bromide colorimetric assay was performed in different tumor cell lines (HCT116 and PC3). The results show that the extract obtained from 70 °C and one cycle of extraction of 10 min exhibited the highest cytotoxic activity against the tested cell lines. The highest yield, however, did not indicate the highest cytotoxic activity, but the optimal extraction conditions were indeed dependent on the temperature (i.e., 70 °C).


Assuntos
Antineoplásicos/química , Própole/química , Álcoois/análise , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Éteres/análise , Humanos , Cetonas/análise , Própole/toxicidade , Terpenos/análise
2.
Ultrason. sonochem ; 18(2): 489-493, Mar.2011.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068320

RESUMO

Allyl 1-naphthyl ethers are useful compounds for different purposes, but reported methods to synthesize them require long reaction times. In this work, we have obtained allyl 1-naphthyl ether in good yield using ultrasonic-assisted methodology in a 1-h reaction. A central composite design was used to obtain a statistical model and a response surface (p < 0.05; R2 = 0.970; R2adj = 0.949; R2 pred = 0.818) that can predict the optimal conditions to maximize the yield, validated experimentally.


Assuntos
Compostos Alílicos/análise , Compostos Alílicos/provisão & distribuição , Compostos Alílicos/síntese química , Éteres/análise , Éteres/provisão & distribuição , Metodologia como Assunto , Ultrassom/métodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-24779620

RESUMO

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, which has recently been developed and validated, was used for the identification and quantification of polyether ionophore, macrolide and lincosamide residues in commercial eggs sold in the metropolitan area of Rio de Janeiro, Brazil. The method was applied to 100 samples and the results showed a high incidence of polyether ionophore residues (25%). Salinomycin was detected in 21% of samples, but only two non-compliant results (5.3 and 53 µg kg(-1)) were found if maximum limits (tolerances) established by European Union were adopted in Brazil and if a method decision limit (CCα) of 3.4 µg kg(-1) was considered. In 8% of analyzed samples, more than one studied coccidiostat was found. The lincosamide, lincomycin, and the macrolide, tylosin, were detected at trace levels in 4 and 1% of the samples, respectively. Lasalocid, clarithromycin and erythromycin were not found.


Assuntos
Ovos/análise , Éteres/análise , Ionóforos/análise , Lincosamidas/análise , Macrolídeos/análise , Resíduos de Praguicidas/análise , Animais , Antibacterianos/análise , Brasil , Galinhas , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Coccidiostáticos/análise , União Europeia , Contaminação de Alimentos/análise , Humanos , Concentração Máxima Permitida , Espectrometria de Massas em Tandem/métodos
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