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Zhou J.,China Agricultural University | Zhou J.,Chinese Academy of Agricultural Sciences | Zhou J.,Apicultural Branch Center | Zhao J.,Chinese Academy of Agricultural Sciences | And 16 more authors.
Analytical Biochemistry | Year: 2010

A high-performance liquid chromatography-diode array detector-tandem mass spectrometry (HPLC-DAD-MS/MS) method was developed for simultaneous determination of melittin and apamin in crude bee venom lyophilized powder (CBVLP) as the traditional Chinese medicine possessing specific biological activity. Melittin and apamin were extracted with pure water from CBVLP samples followed by HPLC-DAD-MS/MS analysis. The method was validated to demonstrate its selectivity, linearity, limit of quantification (LOQ), intraday precision, interday precision, accuracy, recovery, matrix effect, and stability. The assay was linear over the concentration ranges of 1-100 and 0.2-25μg/ml with limit of quantifications (LOQs) of 1.0 and 0.3μg/ml for melittin and apamin, respectively. The precision results were expressed as coefficients of variation (CVs), ranging from 2.2% to 11.4% for intraday repeatability and from 3.2% to 13.1% for interday intermediary precision. The concentrations of endogenous melittin and apamin in CBVLP samples ranged from 46% to 53% and from 2.2% to 3.7% of dry weight, respectively. This rapid, simple, precise, and sensitive method allowed the simultaneous determination of melittin and apamin to evaluate authenticity and quality of CBVLP samples. © 2010 Elsevier Inc.


Xue X.,Chinese Academy of Agricultural Sciences | Xue X.,China Agricultural University | Xue X.,Apicultural Branch Center | Chen L.,Chinese Academy of Agricultural Sciences | And 13 more authors.
Chromatographia | Year: 2012

Determination of the levels of 1-octacosanol is important in food stuff for the study of its pharmacological activities and health benefits. In this study, a novel, simple and fast internal standard method for the non-derivatization ultra-performance liquid chromatographic determination of 1-octacosanol in raw materials and health products was developed and validated based on evaporative light scattering detection. The linearity (r 2 > 0.998), recovery (99.1-100.2%, RSD <2.7%), intra- and inter-day precision (RSD <3.8%), limit of detection (1.0 mg/L), limit of quantification (2.2 mg/L) of the 1-octacosanol were determined. The method was successfully applied to nine real 1-octacosanol products. The results of analyses had close agreement with the labeled claims of 1-octacosanol content in these products. Compared with the classical gas chromatography method, the developed method was simpler, faster and more environmentally friendly due to avoiding any derivatization step. This protocol represents a rapid and feasible method for quality control of 1-octacosanol products. © 2011 Springer-Verlag.


Xue X.,China Agricultural University | Xue X.,Chinese Academy of Agricultural Sciences | Xue X.,Apicultural Branch Center | Zhao J.,Chinese Academy of Agricultural Sciences | And 12 more authors.
Food Chemistry | Year: 2012

A method for the determination of coenzyme Q10 in bee pollen has been developed applying an online cleanup of accelerated solvent extraction and using environmentally acceptable organic solvents. The extracted samples were analysed by high performance liquid chromatography with diode array detection. The optimised method employed 10 mL extraction cells, 1 g sample size, absolute ethanol as extraction solvent, 80 °C of extraction temperature, one extraction cycle, 5 min of static time, Cleanert Alumina-N as sorbent and 60% flush volume. The method was validated by means of an evaluation of the matrix effects, linearity, limit of detection (LOD) and quantification (LOQ), trueness, precision and stability. The assay was linear over the concentration range of 0.25-200 mg/L and the LOD and LOQ were 0.16 and 0.35 mg/kg, respectively. The recoveries were above 90%. The inter- and intra-day precision was below 6.3%. The method has been successfully applied to the analysis of bee pollen samples. For 20 bee pollen products, the coenzyme Q10 content varied from not detectable to 192.8 mg/kg. © 2012 Elsevier Ltd. All rights reserved.


Zhou J.,Chinese Academy of Agricultural Sciences | Zhou J.,Bee Product Quality Supervision and Testing Center | Zhou J.,Apicultural Branch Center | Xu X.,Chinese Academy of Agricultural Sciences | And 7 more authors.
Analytical Methods | Year: 2012

An improved HPLC method was developed for the simultaneous determination of nucleosides in bee pollen samples of various floral origins. Bee pollen samples were dissolved in 35 mL pure water by agitation on a vortex mixer followed by ultrasonic-assisted extraction prior to quantitative analysis. HPLC conditions were optimized and good linearity (r 2 > 0.999) was obtained over the investigated concentration ranges. Precision was evaluated by intra- and inter-day assays and RSD values were below 3.15%. Accuracies ranged from 82.7% to 124.7%, respectively. Finally, the method was successfully applied to the analysis of nucleosides in bee pollen samples and could be used for routine analysis as the standard method. © 2012 The Royal Society of Chemistry.


Zhou J.,Chinese Academy of Agricultural Sciences | Zhou J.,Apicultural Branch Center | Zhao J.,Apicultural Branch Center | Xue X.,Chinese Academy of Agricultural Sciences | And 11 more authors.
Journal of Separation Science | Year: 2010

A rapid method for the analysis of melamine in royal jelly (RJ) and RJ lyophilized powder (RJLP) was developed using ion-pair RP-HPLC coupled with UV detector. The method utilized an optimized buffer system to avoid the elution of melamine near the column void volume and improve retention of melamine in a generic C8 chromatographic column. In addition, sample preparation included deproteination, ultrasonic-assisted extraction, and cleanup on a mixed-mode cation exchange extraction cartridge. The extraction procedure was optimized with regard to the amount of extraction solvent and the duration of sonication for RJ and RJLP samples. The following criteria were used to validate the HPLC-UV detection method: selectivity, linearity, precision, LOD, and LOQ. Correlation coefficient was higher than 0.999 by applying the linear regression model based on the least square method with a weighting factor (1/x). Precision was evaluated as repeatability and intermediary precision with RSD of less than 15%. The mean percentage recoveries of melamine were varied from 72.5 to 90.5% for RJ and RJLP. This approach will be of particular utility for the evaluation of melamine residue level and routine monitoring of melamine in RJ and RJLP samples. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.


Zhou L.,Chinese Academy of Agricultural Sciences | Xue X.,Apicultural Branch Center | Zhou J.,Chinese Academy of Agricultural Sciences | Li Y.,Chinese Academy of Agricultural Sciences | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2012

To obtain insight into the metabolic regulation of adenosine 5'-triphosphate (ATP) in royal jelly and to determine whether ATP and its catabolites can be used as objective parameters to evaluate the freshness and quality of royal jelly (RJ), a rapid ultraperformance liquid chromatography (UPLC) method has been developed for feasible separation and quantitation of ATP and its catabolites in RJ, namely, adenosine 5'-diphosphate (ADP), adenosine 5'-monophosphate (AMP), inosine monophosphate (IMP), inosine (HxR), and hypoxanthine (Hx). The analytes in the sample were extracted using 5% precooled perchloric acid. Chromatographic separation was performed on a Waters Acquity UPLC system with a Waters BEH Shield RP18 column and gradient elution based on a mixture of two solvents: solvent A, 50 mM phosphate buffer (pH 6.5); and solvent B, acetonitrile. The recoveries were in the range of 86.0-102.3% with RSD of no more than 3.6%. The correlation coefficients of six analytes were high (r2 ≥ 0.9988) and within the test ranges. The limits of detection and quantification for the investigated compounds were lower, at 0.36-0.68 and 1.22-2.30 mg/kg, respectively. The overall intra- and interday RSDs were no more than 1.8%. The developed method was successfully applied to the analysis of the analytes in samples. The results showed that ATP in RJ sequentially degrades to ADP, AMP, IMP, HxR, and Hx during storage. © 2012 American Chemical Society.


Zhang Y.-N.,Chinese Academy of Agricultural Sciences | Zhang Y.-N.,Risk Assessment Laboratory for Bee Products Quality and Safety of Ministry of Agriculture | Chen L.-Z.,Chinese Academy of Agricultural Sciences | Chen L.-Z.,Risk Assessment Laboratory for Bee Products Quality and Safety of Ministry of Agriculture | And 9 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2015

At present, the rice syrup as a low price of the sweeteners was often adulterated into acacia honey and the adulterated honeys were sold in honey markets, while there is no suitable and fast method to identify honey adulterated with rice syrup. In this study, Near infrared spectroscopy (NIR) combined with chemometric methods were used to discriminate authenticity of honey. 20 unprocessed acacia honey samples from the different honey producing areas, mixed?with different proportion of rice syrup, were prepared of seven different concentration gradient?including 121 samples. The near infrared spectrum (NIR) instrument and spectrum processing software have been applied in the?spectrum?scanning and data conversion on adulterant samples, respectively. Then it was analyzed by Principal component analysis (PCA) and canonical discriminant analysis methods in order to discriminating adulterated honey, The results showed that after principal components analysis, the first two principal components accounted for 97.23% of total variation, but the regionalism of the score plot of the first two PCs was not obvious, so the canonical discriminant analysis was used to make the further discrimination, all samples had been discriminated correctly, the first two discriminant functions accounted for 91.6% among the six canonical discriminant functions, Then the different concentration of adulterant samples can be discriminated correctly, it illustrate that canonical discriminant analysis method combined with NIR spectroscopy is not only feasible but also practical for rapid and effective discriminate of the rice syrup adulterant of acacia honey. © 2015, Science Press. All right reserved.


Zhou J.,Chinese Academy of Agricultural Sciences | Zhou J.,Apicultural Branch Center | Qi Y.,Texas Heart Institute | Hou Y.,Chongqing Institute of Veterinary Drug and Feed Detection | And 12 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2011

In this paper, a method for the rapid and sensitive analysis of juvenile hormone III (JH III) and 20-hydroxyecdysone (20E) in queen larvae and drone pupae samples was presented. Ultrasound-assisted extraction provided a significant shortening of the leaching time for the extraction of JH III and 20E and satisfactory sensitivity as compared to the conventional shake extraction procedure. After extraction, determination was carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS) operating in electrospray ionization positive ion mode via multiple reaction monitoring (MRM) without any clean-up step prior to analysis. A linear gradient consisting of (A) water containing 0.1% formic acid and (B) acetonitrile containing 0.1% formic acid, and a ZORBAX SB-Aq column (100. mm × 2.1. mm, 3.5 μm) were employed to obtain the best resolution of the target analytes. The method was validated for linearity, limit of quantification, recovery, matrix effects, precision and stability. Drone pupae samples were found to contain 20E at concentrations of 18.0 ± 0.1. ng/g (mean ± SD) and JH III was detected at concentrations of 0.20 ± 0.06. ng/g (mean ± SD) in queen larvae samples. This validated method provided some practical information for the actual content of JH III and 20E in queen larvae and drone pupae samples. © 2011 Elsevier B.V.


Yang J.,Risk Assessment Laboratory for Bee Products Quality and Safety of Ministry of Agriculture Beijing | Yang J.,Chinese Academy of Agricultural Sciences | Chen L.-Z.,Risk Assessment Laboratory for Bee Products Quality and Safety of Ministry of Agriculture Beijing | Chen L.-Z.,Chinese Academy of Agricultural Sciences | And 10 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2016

Botanical origins of propolis are significant factors affecting biological and pharmacological activities because of different components in propolis. Until now, the determination of propolis botanical origins is mainly based on different varieties and the content of the compositions with great limitations. Therefore, it is important to discriminate different botanical origins of propolis quickly and accurately. In this study, Near-infrared (NIR) spectra of propolis varieties based on principal component analysis mahalanobis distance (PCA-mahalanobis distance) model and canonical discriminant analysis model were built for the classification of three botanical origins (poplar propolis,brich propolis and rubber propolis). The models were built based on the optimal pretreatment method and bands of first derivative + Savitzky-Golay (7) filter and 4500~12 000-1, which were selected in advance. After the principal component analysis, the correct classification rates of calibration sets and validation sets in analysis mahalanobis distance models were 93.62% and 82.61%, respectively. The discrimination rate and the cross-validation rate of canonical discrimination models were 91.4% and 88.6%, respectively. Therefore, NIR spectroscopy with chemometric methods is not only feasible but also practical for rapid and accurate identification of varieties of propolis. © 2016, Peking University Press. All right reserved.

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