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1.
Molecules ; 24(8)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999695

RESUMO

Beeswax is useful for the beekeeping sector but also for the agro-food, pharmaceutical or cosmetics sectors. Frequently, this bee product is contaminated with pesticides reducing its utility and causing the decline in its market. This study aimed to prove the effectiveness of an industrial-scale decontamination method in removing acaricides from beeswax. Chlorfenvinphos and coumaphos decrease was higher than 90%, whereas tau fluvalinate decrease was only 30%. No changes were observed in the beeswax content of hydrocarbons and monoesters, whereas a decrease in the concentrations of Ca, Fe, Zn, Hg, Mn and P, and an increase in the concentrations of As and Si were found after the decontamination. Filtration reduced total phenolics, flavonoids and the antioxidant capacity of the lipophilic extract. These results demonstrate that the industrial method used was as effective as the method previously tested on a laboratory scale. The study also contributes to a better knowledge and characterization of beeswax, specially related to trace and ultra-trace elements and antioxidant capacity. Moreover, it offers the chance to further develop a method to effectively detect wax adulterations based on the chemical elements profile.


Assuntos
Acaricidas/química , Antioxidantes/química , Descontaminação , Metais Pesados/química , Ceras/química , Animais , Abelhas
2.
J Agric Food Chem ; 52(20): 6347-52, 2004 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-15453712

RESUMO

In this work, the occurrence of ochratoxin A (OTA) in 170 samples of cocoa products of different geographical origins was studied. An immunoaffinity column with HPLC separation was developed to quantify low levels of OTA in cocoa bean, cocoa cake, cocoa mass, cocoa nib, cocoa powder, cocoa shell, cocoa butter, chocolate, and chocolate cream with >80% recoveries. The method was validated by performing replicate analyses of uncontaminated cocoa material spiked at three different levels of OTA (1, 2, and 5 microg/kg). The data obtained were related on the acceptable safe daily exposure for OTA. The highest levels of OTA were detected in roasted cocoa shell and cocoa cake (0.1-23.1 microg/kg) and only at minor levels in the other cocoa products. Twenty-six cocoa and chocolate samples were free from detectable OTA (<0.10 microg/kg). In roasted cocoa powder 38.7% of the samples analyzed contained OTA at levels ranging from 0.1 to 2 microg/kg, and 54.8% was contaminated at >2 microg/kg (and 12 samples at >3 microg/kg). Ochratoxin A was detected in cocoa bean at levels from 0.1 to 3.5 microg/kg, the mean concentration being 0.45 microg/kg; only one sample exceeded 2 microg/kg (4.7%). In contrast, 51.2% of cocoa cake samples contained OTA at levels > or =2 microg/kg, among which 16 exceeded 5 microg/kg (range of 5-9 microg/kg). These results indicate that roasted cocoa powder is not a major source of OTA in the diet.


Assuntos
Cacau/química , Contaminação de Alimentos/análise , Ocratoxinas/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/análise , Ocratoxinas/toxicidade , Suínos
3.
Pest Manag Sci ; 66(11): 1230-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20661942

RESUMO

BACKGROUND: The purpose of this work was to determine residues of acaricides in recycled Spanish beeswax. RESULTS: Chlorfenvinphos, fluvalinate, amitraz, bromopropylate, acrinathrin, flumethrin, coumaphos, chlorpyrifos, chlordimeform, endosulfan and malathion residues were determined by GC-µECD/NPD/MS detection. Owing to the extreme instability of amitraz, this analyte was transformed into the stable end-metabolite 2,4-dimethylaniline, later derivatised with heptafluorobutyric anhydride and determined by GC-µECD/MS. Recoveries from spiked samples ranged from 86 to 108%, while quantification limits varied from 0.10 to 0.30 mg kg(-1) using GC-µECD/NPD, and from 12 to 85 µg kg(-1) by GC-MSD. Of a total of 197 samples analysed, only eight samples (4%) were free of residues of chlorfenvinphos (0.019-10.6 mg kg(-1)), fluvalinate was present in 93.6% of samples analysed (0.027 -88.7 mg kg(-1)), while coumaphos was confirmed in only five of the 134 samples analysed at concentrations of less than 195 µg kg(-1). The remaining acaricides were identified with different levels of incidence at concentrations from 12 to 231 µg kg(-1). CONCLUSIONS: Residues of acaricides were found in an extensive number of beeswax samples. The contamination with chlorfenvinphos and tau-fluvalinate was very relevant, particularly as chlorfenvinphos is not legally authorised for use in beekeeping. The possible impacts of the main acaricides detected on larval and adult honey bees are discussed.


Assuntos
Acaricidas/análise , Abelhas/parasitologia , Resíduos de Praguicidas/análise , Ceras/química , Animais , Espectrometria de Massas , Controle de Pragas , Espanha , Varroidae
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