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Orantes Bermejo F.J.,Apinevada Analytical Laboratory of Bee Products
Food Chemistry | Year: 2012

The physical and chemical parameters (melting point and saponification number), and the fraction of hydrocarbons, monoesters, acids and alcohols have been determined in 90 samples of Spanish commercial beeswax from Apis mellifera L. The adulteration with paraffins of different melting point, cow tallow, stearic acid, and carnauba wax were determined by HTGC-FID/MS detection, and the research was focussed mainly on paraffins and microcrystallines waxes. In general, the added adulterant can be identified by the presence of non-naturally beeswax components, and by the differences of values of selected components between pure and adulterated beeswax. The detection limits were determined using pure and adulterated beeswax with different amounts of added waxes (5%, 10%, 20% and 30%). Percentages higher than 1-5% of each adulterant can be detected in the mixtures. Paraffin waxes were confirmed in 33 of the 90 samples analysed at concentrations between 5% and 30%. © 2011 Elsevier Ltd. All rights reserved. Source

Bonvehi J.S.,Research and Development of Nederland Co. | Bermejo F.J.O.,Apinevada Analytical Laboratory of Bee Products
Environmental Monitoring and Assessment | Year: 2013

The aim of this work is to determine the content of essential and toxic elements in 25 raw propolis samples, when considering pollution agents and geographical and botanical factors. The microwave-assisted digestion was the most reliable and accurate method for determination of inorganic elements in propolis samples. The results were obtained using certified reference materials in a good agreement with certified values. Inductively coupled plasma atomic emission spectroscopy was used for the determination of 23 macro- and microelements (Ag, Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Sb, Se, Si, Sn, and Zn). A Mercury analyzer was also utilized for the detection of the total Hg. Among the analyzed metals, Ca, K, Mg, Zn, Si, S, Fe, Al, P, and Na were found to be the most predominant. Heavy metals (As, Cd, Hg, and Pb) were determined in minimal concentration, and Pb was the highest mean contained toxic (<3.80 mg/kg), without influence on provisional tolerable weekly intake values. The method can be applied for routine analysis and quality and environmental pollution controls of toxic elements in propolis samples. The results obtained indicate no pollution of the collection areas and naturally high concentration of Al (460 ± 62.2 mg/kg). © 2012 Springer Science+Business Media Dordrecht. Source

Orantes-Bermejo J.,Apinevada Analytical Laboratory of Bee Products
Pest Management Science | Year: 2010

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. © 2010 Society of Chemical Industry. Source

Kumazawa S.,University of Shizuoka | Bonvehi J.S.,Research and Development of Nederland Co. | Torres C.,Apinevada Analytical Laboratory of Bee Products | Mok-Ryeon A.,Dong - A University | And 2 more authors.
Phytochemical Analysis | Year: 2013

Introduction Propolis is a complex mixture of natural sticky, gummy and resinous components produced by honeybees (Apis mellifera L.) from plant materials. However, phytochemical data of the Andalusian (southern Spain) propolis are scant. Objective The primary objectives of this study were to chemically characterise the compounds and evaluate the anti-oxidant activity found in 28 Andalusian propolis samples. Methods Ethanol extracts of propolis (EEP) were prepared and examined for their anti-oxidant activity by 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) and 2,2-diphenyl-1-picrylhydrazyl assays. To characterise the phenolic composition, the presence of 11 compounds was identified by HPLC analysis with photodiode array and mass spectrometric detection. Results All propolis samples had strong anti-oxidant activity, accompanied by high total phenolic content. The most abundant compounds were flavonoids. Concerning the phenolic compounds content, our results showed that the 75% of the samples analysed contained at least 80 mg/g of flavonoids, primarily pinobanksin 3-acetate, pinocembrin, chrysin, galangin and pinobanksin. Caffeic acid phenethyl ester was detected in almost all EEP samples but in smaller proportions (mean 12.9 ± 2.8 mg/g). Conclusion The present investigation constitutes the first comprehensive report on the phenolics identified in southern Spanish propolis. The results revealed that the samples tested showed a high scavenging activity and therefore indicate the possible use of Andalusian propolis as an important source of natural anti-oxidants. Copyright © 2013 John Wiley & Sons, Ltd. Source

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