To ensure that egg-containing products, such as dried eggs and egg pasta, conform to the technological and legislative requirements for egg content, methods are needed to determine the amount of cholesterol in such products. The conventional approach, direct saponification and hexane extraction followed by cholesterol determination by gas chromatography coupled to a flame ionization detector, is very time consuming. Therefore, we developed a rapid method on the basis of direct analysis in real time coupled to time-of-flight mass spectrometry. Samples were prepared simply by solvent extraction followed by extract filtration. The optimization of certain parameters, including the solvent used and direct analysis in real time ionization gas temperature, had a pronounced effect on the intensities of the produced ions, in particular, the molecular and dehydrated ions of cholesterol and its deuterated analog, cholesterol 2,2,3,4,4,6-d(6) which was used as an internal standard. For the developed method, limits of detection and quantification were 0.03 and 0.05 mg g(-1) respectively. The results of the real samples were compared with those obtained using the conventional approach [limit of detection = 0.002 mg g(-1) and limit of quantification = 0.05 mg g(-1)], and it was found that, although the results obtained using the conventional approach were more accurate, our developed method is much simpler and faster, where the time was dramatically reduced by 87% for executing a screening analysis.

• Klíčová slova
• GC-FID, ambient mass spectrometry, cholesterol, direct analysis in real time, egg pasta,
• Publikační typ
• časopisecké články MeSH

An on-line coupled capillary isotachophoresis - capillary zone electrophoresis method for the determination of lysozyme in selected food products is described. The optimized electrolyte system consisted of 10 mM NH(4)OH + 20 mM acetic acid (leading electrolyte), 5 mM epsilon -aminocaproic acid +5 mM acetic acid (terminating electrolyte), and 20 mM epsilon -aminocaproic acid +5 mM acetic acid +0.1% m/v hydroxypropylmethylcellulose (background electrolyte). A clear separation of lysozyme from other components of acidic sample extract was achieved within 15 min. Method characteristics, i.e., linearity (0-50 micrograms/mL), accuracy (recovery 96+/-5%), intra-assay (3.8%), quantification limit (1 microgram/ml), and detection limit (0.25 microgram/mL) were determined. Low laboriousness, sufficient sensitivity and low running costs are important attributes of this method. The developed method is suitable for the quantification of the egg content in egg pasta.

• MeSH
• analýza potravin MeSH
• elektroforéza kapilární ekonomika   metody   MeSH
• elektrolyty chemie   MeSH
• kalibrace MeSH
• koncentrace vodíkových iontů MeSH
• muramidasa analýza   normy   MeSH
• senzitivita a specificita MeSH
• spektrofotometrie ultrafialová MeSH
• vaječné proteiny dietní analýza   MeSH
• vaječný bílek analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• elektrolyty MeSH
• muramidasa MeSH
• vaječné proteiny dietní MeSH

Tests were performed to examine the effectiveness of a new form of cambendazole (Bonlam paste, produced by MSD, USA) in sheep, naturally invaded by the trematodes Dicrocoelium dendriticum. Single administration of 25 mg per 1 kg live weight induced a rapid decrease in the number of the excreted eggs of D. dendriticum, as counted during ovoscopic examination seven, ten, and fifteen days after administration of the chemical. The intenseffectiveness of the preparation, determined post mortem, was 95.1%. Despite this, several dicrocoelia with normal motility and with no changes on the cuticle or internal organs were found in all the animals dissected. The animals tolerated the treatment with no signs of side-effects.

• MeSH
• benzimidazoly farmakologie   MeSH
• Dicrocoelium účinky léků   MeSH
• dikrocelióza farmakoterapie   veterinární   MeSH
• kambendazol farmakologie   terapeutické užití   MeSH
• masti MeSH
• nemoci ovcí farmakoterapie   MeSH
• ovce MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• benzimidazoly MeSH
• kambendazol MeSH
• masti MeSH