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Highlights: [•] Twelve of flavonoids were quantified in honey samples by HPLC–DAD–MS/MS. [•] Three floral markers were found to discriminate honey samples. [•] Fingerprint feature areas were achieved to classify honey samples. [•] Honey samples could be successfully classified on the basis of chemometrics models. [ABSTRACT FROM AUTHOR]

Abstract: 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 (100mm×2.1mm, 3.5μm) 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±0.1ng/g (mean±SD) and JH III was detected at concentrations of 0.20±0.06ng/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. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: An analytical method in propolis was developed and validated for the determination of four tetracyclines (TCs) by high performance liquid chromatography (HPLC) for the first time. After extraction by ultrasound, the extracting solution was subjected to Oasis HLB and weak cation-exchange cartridge to remove water-soluble and fat-soluble flavonoids, aromatic acids, terpenoid compounds, wax, and pollen debris. The calibration curves of fortified samples showed acceptable linear response (R 2 >0.99) through a range of 100–5000ngg−1 in 20 replicates of six concentrations and the analysis of variance (ANOVA) was performed to validate the regression data. The limit of quantification of four TCs were 100 and 150ngg−1, respectively. The recoveries of the four TCs for propolis samples spiked with 100–500ngg−1 were in the range of 61.9–88.5% and the RSDs were between 4.80% and 13.2%. Traces of tetracycline were found in two out of 30 analysed real samples. [Copyright &y& Elsevier]

Abstract: A rapid fingerprint method was developed for investigating and inferring geographical origin of Chinese propolis by using high performance liquid chromatography–ultraviolet detection (HPLC–UV). 120 samples were analyzed from 17 different locations of 10 provinces of China in this study. In the HPLC chromatograms, eight major compounds were identified as flavonoids, including rutin, myricetin, quercetin, kaempferol, apigenin, pinocembrine, chrysin and galangin. Both correlation coefficient of similarity in chromatograms and relative peak areas of characteristic compounds were calculated for quantitative expression of the HPLC fingerprints. Our results revealed that the presence or absence of specific peaks and similarity evaluation in simulative mean chromatograms among different regions could efficiently identify and distinguish Chinese propolis from different geographical origins. [Copyright &y& Elsevier]

A robust and sensitive method of solid-phase extraction followed by liquid chromatography-tandem mass spectrometry (LC–MS/MS) was established and performed for the simultaneous determination of eleven aminoglycosides (AGs) in royal jelly and honey. After sample extraction by a phosphate buffer containing trichloroacetic acid (TCA) and ethylenediaminetetracetic acid disodium salt (Na 2 EDTA), the extraction solution was subjected to a parallel solid-phase extraction for clean-up prior to the LC–MS/MS analysis. The same method was applied to analyze two completely different matrices, honey and royal jelly. Good sensitivity, repeatability, and recovery were obtained by using the mobile phase without an ion-pairing reagent such as heptafluorobutyric acid (HFBA) or sodium heptanesulfonate. The calibration curves of the honey and royal jelly samples exhibited a good linear response (R 2  > 0.99) at six concentrations in the range of 10–1000 μg/mL. The limit of quantification (LOQ) of the AGs ranged from 10 to 25 μg/kg in the honey and from 12.5 to 25 μg/kg in the royal jelly. The recoveries of the AGs for the honey and royal jelly samples were in the range of 79.48% to 108.95% and 74.61% to 113.70% respectively and the relative standard deviations (RSDs) were between 1.23% and 9.59%, and between 1.51% and 9.98%, respectively. The proposed approach has been allowed in China as a reference method for the simultaneous determination of eleven AGs in honey and royal jelly. [ABSTRACT FROM AUTHOR]

Honey discrimination based on floral and geographic origins is limited by the ability to determine reliable markers because developing hypothetical substances in advance considerably limits the throughput of metabolomics studies. Here, we present a novel approach to screen and elucidate honey markers based on comparative untargeted metabolomics using ultrahigh-performance liquid chromatography-hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Orbitrap). To reduce metabolite information losses during sample preparation, the honey samples were dissolved in water and centrifuged to remove insoluble particles prior to UHPLC-Q-Orbitrap analysis in positive and negative electrospray ionization modes. The data were pretreated using background subtraction, chromatographic peak extraction, normalization, transformation and scaling to remove interferences from unwanted biases and variance in the experimental data. The pretreated data were further processed using principal component analysis (PCA) and a three-stage approach ( t -test, volcano plot and variable importance in projection (VIP) plot) to ensure marker authenticity. A correlation between the molecular and fragment ions with a mass accuracy of less than 1.0 ppm was used to annotate and elucidate the marker structures, and the marker responses in real samples were used to confirm the effectiveness of the honey discrimination. Moreover, we evaluated the data quality using blank and quality control (QC) samples based on PCA clustering, retention times, normalized levels and peak areas. This strategy will help guide standardized, comparative untargeted metabolomics studies of honey and other agro-products from different floral and geographic origins. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop an analytical method for the analysis of a wide range of veterinary drugs in honey and royal jelly. A modified sample preparation procedure based on the quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed, followed by liquid chromatography tandem mass spectrometry determination. Use of the single sample preparation method for analysis of 42 veterinary drugs becomes more valuable because honey and royal jelly belong to completely different complex matrices. Another main advantage of the proposed method is its ability to identify and quantify 42 veterinary drugs with higher sensitivity than reference methods of China. This work has shown that the reported method was demonstrated to be convenient and reliable for the quick monitoring of veterinary drugs in honey and royal jelly samples. [ABSTRACT FROM AUTHOR]

Abstract: 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 10mL extraction cells, 1g sample size, absolute ethanol as extraction solvent, 80°C of extraction temperature, one extraction cycle, 5min 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 0.25–200mg/L and the LOD and LOQ were 0.16 and 0.35mg/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 192.8mg/kg. [Copyright &y& Elsevier]