Authors:B. Sas, G. Domány, Ilse Gyimóthy, Katalin Gaál Kovácsné, and M. Süth
The effect of free-range versus cage management system on corticosterone transfer into the eggs was studied in laying hens. Hungarian Yellow laying hens (age: 21 weeks, body weight: 2.0 ± 0.5 kg) were divided into two groups in the spring: Group I, free-range keeping (n = 15 layers, density: ≯ 0.5 bird/m2) in outdoor runs, with continuous access to a commercial layer feed; Group II, hens kept in battery cages (n = 17 layers, density: 2 birds/m2, natural light, continuous access to feed and water). Eggs were collected after a one-week adaptation period on days 2, 7 and 16. Corticosterone (CST) was extracted from homogenised egg samples using an ASE-200 Accelerated Solvent Extractor and then assayed by liquid chromatography linked with tandem mass spectrometry (LC-MS/MS) [Thermo Quest Surveyor high-performance liquid chromatography (HPLC) interfaced via Atmospheric Pressure Chemical Ionisation (APCI) ion source to Finnigan/Thermo Quest LCQ Deca MS/MS] using dexamethasone as internal standard with positive APCI ionisation. CST concentrations of whole eggs laid by free-range hens on days 2, 7 and 16 were 0.370 ± 0.218, 0.259 ± 0.066 and 0.915 ± 0.745 ng·g-1, respectively, while those of eggs laid by caged hens were 0.206 ± 0.157, 0.223 ± 0.165 and 0.184 ± 0.110 ng·g-1 at the above sampling times. It is concluded that in free-range laying hens the sharp changes of environmental weather conditions significantly increased the corticosterone content of eggs, while the environmentally controlled and closed battery cage management technology resulted in relatively uniform corticosterone concentrations in the whole eggs.
Schizonepeta tenuifolia Briq. (ST) has been used as an aromatic exterior-releasing medicine in clinical practice for thousands of years in China. Previous researches have revealed both volatile oil (STVO) and aqueous extract (STAE) from ST showed significant pharmacological activities, such as anti-virus, anti-inflammation, anti-oxidation, and immunoregulation. However, the influence between each other was still unknown. The purpose of this study was to compare the pharmacokinetic profiles of three main flavonoids (luteoloside, apigetrin, and hesperidin) in STAE to illustrate the influence of STVO. A liquid chromatography-tandem mass spectrometry (HPLC-MS) method was established to quantitatively analyze the three absorbed ingredients in the plasma of healthy rats. Biological samples were analyzed on an Agilent Eclipse Plus C18 column (3.0 mm × 150 mm, 3.5 μm) with gradient mobile phase (containing 0.2% formic acid and acetonitrile) at a flow rate of 0.8 mL/min. All the analytes and quercitrin (IS) were investigated with an electrospray ionization source (ESI) using multiple-reaction monitoring (MRM) in negative ionization mode. In addition, this quantitative method showed good linearities (r ≥ 0.9995) and the lower limits of quantification were 0.590–1.19 ng/mL. The intra- and inter-day precisions ranged 3.47–10.45% and 4.29–11.28% for the three analytes. The mean extraction recoveries were in the range of 77.41–109.79% and the average matrix effects were within 83.41–112.67%. The validated method has been fully applied to compare the pharmacokinetic parameters of the three flavonoid glycosides in rat plasma after oral administration of STAE and STAE+STVO. In comparison of luteoloside, apigetrin, and hesperidin in STAE group, it was found that different degree of increasing existed for the time to reach the maximum concentration (Tmax), elimination half-life time (T1/2), the area under the concentration curves (AUC0→t and AUC0→∞) and the maximum concentrations (Cmax) in STAE+STVO group. As can be seen from above results, STVO could improve the absorption and bioavailability of the three analytes. These findings would provide some active and strong basis of safe clinical application for ST and further exploitation for STVO from the perspective of drug–drug interaction.
. Elaneeda , Development and validation of fast and simple flow injection analysis-tandemmassspectrometry (FIA-MS/MS) for the determination of metformin in dog serum , J. Pharm. Biomed. Anal. 107 ( 2015 ) 229 – 235 .
, H. , GERMAN , J.B. , KJELDEN , R. , LEBRILLA , C.B. , BARILE , D. ( 2013 ): Quantitative analysis of gangliosides in bovine milk and colostrum-based dairy products by ultra-high performance liquid chromatography-tandemmassspectrometry