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Abstract Salvia miltiorrhiza has been widely used in Asia for medicinal purposes for >1000 years due to the high levels of bioactive constituents it contains. In this study, a simple and rapid ultrasound-assisted liquid extraction (5 min) was applied for the extraction of these bioactive constituents. The extracts were analyzed by using rapid ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with simultaneous positive and negative electrospray ionization in a single analytical run. Eight analytes were separated within 2.2 min during 6 min of run time with UHPLC-MS/MS operated in multiple reaction monitoring (MRM) mode. The concentration of salvianolic acids and tanshinones in the different organs of different varieties of Salvia miltiorrhiza ranged from 6.4 to 382.1 mg/g and 0.03 to 31.7 mg/g, respectively. To the best of our knowledge, this is the first report to characterize the tanshinone compounds found in the flower and stem/leaf of Salvia miltiorrhiza by UHPLC-MS/MS. Highlights • First report of tanshinones were found in leaf and flower from Salvia Miltiorrhiza. • A simple and rapid ultrasound-assisted liquid extraction was developed. • High throughput screening method by UPLC-MS/MS operated in MRM mode. • Salvianolic acid and tanshinones were quantified within 2.2 min in 6 min run time. [ABSTRACT FROM AUTHOR]

Background: Cassia auriculata (Avaram) is an important medicinal plant in India Improved awareness in medicinal flowers has led to an increased need for efficient extraction methods and screening of flavonoid derivatives. Objective: To standardization of extraction solvent system and Characterization of flavonoids through positive and negative electrospray ionization mode using LC-MS/MS from Cassia auriculata extract. Materials and Methods: The different solvents like Methanol, Water, Acetonitrile, Ethyl Acetate, Ethanol, Chloroform, Hexane, Acetone Diethyl ether used frot he identification of flavonoids (Gallic acid, Theanine, Theobromine, Theophylline, Caffeic acid, Caffeine, Ferulic acid, Theacrine, Catechin, Quercetin, EpiGallo Catachin, catechin gallate, Epicatachin gallate and Quercetin hexoside. Results: Based on the peak area percentage the extraction solvent was standardized. The percentage of relative & absolute intensity of screened flavonoids was observed using LC-MS in positive and negative electrospray ionization. The results show that the methanol extract has more percentage of peak area, relative intensity and absolute intensity. The MS results showed that the negative ionoization has more intensity values of flavonoids and the signal-to-noise ratio was high in negative ionization mode compare to positive mode. Conclusion: Based on the results the methanol is the suitable extraction solvetnt and negative ionization mode of ESI-LC-MS/MS was appropriate for the screening of flavonoids on Cassia auriculata flower extracts. [ABSTRACT FROM AUTHOR]

Liquid chromatography coupled with mass spectrometry (LC-MS) has shown great potential in analysis complex samples. However, informative feature extraction is still challenge since the electrospray ionization in LC-MS tends to produce ninety percent or more ions not originated from compounds of interest. The concept of pure ion chromatogram (PIC) is effective to extract informative ions, but tradition PIC methods are time-consuming because of their theories and programming languages. In this study, we present a novel method, called Fast Pure Ions Chromatograms (FPIC), for extracting PICs from raw LC-MS dataset effectively and quickly. This method can search ion of PIC from its maximum bi-directionally and adaptively, which can improve the stability and reduce the computation time drastically. A further speedup has been achieved by exploiting modern software engineering techniques. FPIC was validated by analyzing four LC-MS datasets: MM14 and MM48, simulated MM48 and quantification (MTBLS234) datasets. Results show that FPIC outperformed traditional methods in the recall, precision and F-score, and it has good reliability of quantification. Furthermore, the method is very fast with few adjustable parameters, which leads to an approximately 125-fold speedup over PITracer and 18-fold speedup over XCMS. An open source implementation of the FPIC method is available at https://github.com/zmzhang/pymass . [ABSTRACT FROM AUTHOR]

A rapid, simple and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC–MS/MS) method was developed for simultaneous determination of amitraz, chlordimeform, formetanate and their main metabolites, N -(2,4-dimethylphenyl)- N -methyl-formamidine (DMPF), 2,4-dimethylformamidine (DMF), 2,4-dimethylaniline (DMA), 4-chloro-2-methylaniline and 3-hydroxyacetanilide in human urine. The urine samples were mixed with buffer solutions (pH 8) and subsequently cleaned up by solid supported liquid/liquid extraction (SLE). The target analytes were efficiently separated with a Waters Atlantis T3 column (150 mm × 4.6 mm, 5 μm), ionized with electrospray ion source in positive mode, and quantitatively determined by tandem mass spectrometry in the multiple reaction monitoring (MRM) mode. In order to minimize matrix effects, the matrix-matched calibration curves of eight analytes were adopted with correlation coefficients (R 2 ) above 0.99. The method were further validated by determining the limits of detection (LODs, 0.3–0.6 ng/mL), the limits of quantitation (LOQs, 1.0–2.0 ng/mL) and recoveries (89.1%–108.4%) with intra-day and inter-day relative standard deviation (RSD, <11%). The established method was applied and demonstrated in a real case by assaying a urine sample from a female poisoned by formetanate. The achieved results proved this method to be rapid, sensitive and accurate for simultaneous quantitation of eight analytes in human urine for intended forensic cases of human poisoning. [ABSTRACT FROM AUTHOR]

A rapid extraction method was developed and validated for levo-tetrahydropalmatine ( l -THP) determination in rabbit plasma by liquid chromatography tandem–mass spectrometry (LC–MS/MS). The sample preparation included a single-step acetonitrile extraction and salting out liquid–liquid partitioning from the water in plasma with MgSO 4 . Berberine was used as internal standard. The mass spectrometry source was negative electrospray ionization. The method showed good performance in the concentration range from 5 to 200 ng mL −1 . The limit of quantification (LOQ) was 1 ng mL −1 . The method was successfully applied to a pharmacokinetic study in rabbit comparing the two drug formulation of l -THP including the raw material and the self-microemulsifying drug delivery system pellet. [ABSTRACT FROM AUTHOR]

In this study, a reliable and fast method using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction procedure without any clean-up step was developed for simultaneous extraction of 15 mycotoxins, i.e., aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, aflatoxin M1, aflatoxin M2, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, de-epoxy-DON, zearalenone, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol, from eggs. High-performance liquid chromatography tandem mass spectrometry was used to separate and detect all of the analytes. Electrospray ionization at both negative and positive modes and multiple reaction-monitoring mode were applied to detect these analytes. The main factors, such as extraction time, extraction solvent, evaporation temperature, and pH of the solvent, were carefully optimized to improve the extraction efficiency. The coefficients of determination of the calibration curves ranged from 0.9884 to 0.9998. The recoveries of most of the analytes were between 71.3% and 105.4% at three concentration levels, except for AFB1 that showed recovery rates of not more than 67.5% in all concentrations. The repeatability and intra-lab reproducibility of this method were both lower than 15% and 25%, respectively. The limit of quantification ranged from 0.2 μg/kg to 5 μg/kg. The matrix effect was evaluated and reduced by the use of matrix-matched calibration curves. The validated method was applied in a pilot study to analyze mycotoxin contamination in 12 eggs, and trace amounts of deoxynivalenol, 15-acetyldeoxynivalenol, aflatoxin B1, aflatoxin G2, zearalenone and β-zearalenol were detected in these samples. [ABSTRACT FROM AUTHOR]

RATIONALE A simple method to introduce unprocessed samples into a solvent for rapid characterization by liquid introduction atmospheric pressure ionization mass spectrometry has been lacking. The continuous flow, self-cleaning open port sampling interface introduced here fills this void. METHODS The open port sampling interface used a vertically aligned, co-axial tube arrangement enabling solvent delivery to the sampling end of the device through the tubing annulus and solvent aspiration down the center tube and into the ionization source of the mass spectrometer via the commercial APCI emitter probe. The solvent delivery rate to the interface was set to exceed the aspiration rate, creating a continuous sampling interface along with a constant, self-cleaning spillover of solvent from the top of the probe. RESULTS Using the open port sampling interface with positive ion mode APCI and a hybrid quadrupole time-of-flight mass spectrometer, rapid, direct sampling and analysis possibilities are exemplified with plastics, ballpoint and felt tip ink pens, skin, and vegetable oils. These results demonstrated that the open port sampling interface could be used as a simple, versatile and self-cleaning system to rapidly introduce multiple types of unprocessed, sometimes highly concentrated and complex, samples into a solvent flow stream for subsequent ionization and analysis by mass spectrometry. The basic setup presented here could be incorporated with any self-aspirating liquid introduction ionization source (e.g., ESI, APCI, APPI, ICP, etc.) or any type of atmospheric pressure sampling-ready mass spectrometer system. CONCLUSIONS The open port sampling interface provides a means to introduce and quickly analyze unprocessed solid or liquid samples with the liquid introduction atmospheric pressure ionization source without fear of sampling interface or ionization source contamination. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new method based on the use of porous organogel materials in combination with liquid chromatography–tandem mass spectrometry (LC–MS–MS) was assessed for the quantification of trace contaminants in complex matrices. As a demonstration of the use of these new materials, the contaminant chosen as a model was bisphenol A (BPA) and its extraction was investigated in urine. Organogel materials consist of an organic solvent immobilized by an organogelator. The composition of the organogel materials was optimized in terms of extraction efficiency and compatibility with LC–MS–MS. Porosity was introduced into the organogel by means of the particulate leaching method using sugar crystals. This new absorbing material is simple to use; the extraction method is reduced to a few steps. The originality of the method lies in the complete dissolution of the material for analysis by LC–MS–MS. The matrix effect of the organogel components was studied and was found to be minimal in atmospheric-pressure chemical ionization (APCI) compared to electrospray ionization (ESI) in negative mode. The influence of matrix components on the extraction was investigated by working with different media (acidified water, synthetic urine, horse urine and human urine). The partition coefficient was not affected within the margin of error (±0.1). After optimization, bisphenol A recoveries from urine samples reached 80%. The actual concentration factor was 10. The relative standard deviation (RSD, n = 6) for the extraction and determination of BPA in horse urine spiked at 10 ng mL −1 was 9%. Tests with spiked human urine showed that the extraction performances were the same as with the solutions tested previously. The use of porous organogel allowed a fast, simple, sensitive, robust, green method to be developed for the determination of trace contaminants in complex matrices. [ABSTRACT FROM AUTHOR]

A new method was developed to determine sulforaphane (SFN) in honey using liquid chromatography tandem mass spectrometry (LC–MS/MS) with electrospray ionization (ESI). An efficient extraction procedure was proposed (average analyte recoveries were between 92% and 99%); this involved a solid phase extraction (SPE) with a polymeric sorbent. Chromatography was performed on a Synergi™ Hydro analytical column with a mobile phase of 0.02 M ammonium formate in water and acetonitrile, at a flow rate of 0.5 mL/min. The method was fully validated in terms of selectivity, limits of detection (LOD) and quantification (LOQ), linearity, carry-over effect, reinjection reproducibility, precision and accuracy. The LOD and LOQ values were below 0.8 μg/kg and 2.6 μg/kg, respectively. The proposed method was applied to analyze SFN in honey from different botanical origins (rosemary, multifloral, orange blossom and heather), and SFN was detected at trace levels in some of the honey samples examined. [ABSTRACT FROM AUTHOR]

A simple to construct and operate, "dip-in" electromembrane extraction (EME) probe directly coupled to electrospray ionization-mass spectrometry (ESI-MS) for rapid extraction and real time analysis of various analytes was developed. The setup demonstrated that EME-MS can be used as a viable alternative to conventional protein precipitation followed by liquid chromatography–mass spectrometry (LC–MS) for studying drug metabolism. Comparison of EME-MS with LC–MS for drug metabolism analysis demonstrated for the first time that real time extraction of analytes by EME is possible. Metabolism kinetics were investigated for three different drugs: amitriptyline, promethazine, and methadone. By comparing the EME-MS extraction profiles of the drug substances and formed drug metabolites with the metabolism profiles obtained by conventional protein precipitation followed by LC–MS good correlation was obtained with only very limited time delay in the extraction. The results indicate that, by tuning the electromembrane properties, for example, by optimizing the extraction voltage, extremely fast extraction kinetics can be obtained. A metabolic profile could be generated while the drug was metabolized offering a significant time saving as compared to conventional LC–MS where laborious protein precipitation or other sample pretreatments are required before analysis. This makes the developed EME-MS setup a highly promising sample preparation method for various kinds of applications where fast and real-time analysis of analytes is of interest. [ABSTRACT FROM AUTHOR]

Two different innovative approaches were used for the determination of nonsteroidal anti-inflammatory drugs (NSAIDs) in water: stir bar sorptive extraction (SBSE) and passive sampling, followed by electrospray ionization liquid chromatography–tandem mass spectrometry. SBSE was developed by comparing EG-Silicone and PDMS stir bars and optimizing main parameters to attain high preconcentration. Quantitative analysis was carried out by mass spectrometry in negative ionization mode and multiple reaction monitoring. The SBSE-LC-MS/MS method provided satisfactory figures of merit with LOD (7.5–71 ng L −1 ) and LOQ (22.5–213 ng L −1 ). The developed method was successfully applied to real samples collected from river water and wastewater effluents. The obtained results showed the presence of all analytes at trace levels, in a wide range of concentrations. The passive sampling approach was carried out by using Polar Organic Chemical Integrative Sampler (POCIS); samplers were deployed for 15 days in river and tap water, allowing to detect analytes at ultra-trace levels. Time-Weighted Average concentration of NSAIDs in river water was estimated in the range 0.33–0.46 ng L −1 , using the sampling rates previously obtained by means of a simple calibration system. [ABSTRACT FROM AUTHOR]

A liquid chromatography/tandem mass spectrometry method for the determination of intracellular accumulation in addition to transcellular transport of digoxin and ouabain in renal epithelial HK-2 cells was developed. The solid-phase extraction Bond Elut ® C18 (100 mg/1 mL) cartridge was used for the extraction of digoxin and ouabain from extracellular (medium) and intracellular (cell lysate) matrices. Chromatographic separation was performed on a CAPCELL PAK C18 MGII column (2.0 mm × 150 mm, 5 μm). This method covered a linear range of 0.5–1000 ng/mL of concentrations in medium and 0.5–1000 ng of concentrations in cell lysate for digoxin and ouabain. The intra-day precision and inter-day precision of analysis were less than 11.9%, and the accuracy was within ±11.6%. The total run time was 16 min. Our method was successfully applied to the transport experiments of digoxin and ouabain by HK-2 cell monolayers. [ABSTRACT FROM AUTHOR]

An automated analyte electroextraction and preconcentration system, which was used as the front end for a liquid chromatography-electrospray mass spectrometry instrument, is described. The extraction was based on driving the anionic analytes across a polymer inclusion membrane by application of a potential of 200 V to the cell. Five milliliters (5 mL) of sample were passed through a flow-through cell at a flow rate of 0.2 mL/min containing a membrane 20 μm thick. This consisted of 75% cellulose triacetate as base polymer, 12.5% of tris(2-ethylhexyl)phosphate as plasticizer, and 12.5% of Aliquat 336 as cationic carrier. The target analytes were enriched in 20 μL of a stagnant acceptor solution prior to online LC/MS analysis. The performance of the system was demonstrated for the determination of chlorinated phenoxyacetic acid herbicides in spiked river water. Enrichment factors of ~200 were achieved with recoveries of typically 99% and precision values of typically 5%. The limit of detection (LOD) values were found to be between 0.03 ng/mL to 0.08 ng/mL. [ABSTRACT FROM AUTHOR]

Highlights: [•] Twelve intact glucosinolates were determined in broccoli leaves by LC-DAD–ESI-MS. [•] The extraction was optimized by means of a Box–Behnken design and ANOVA. [•] The proposed extraction method based on MW heating has proven to be efficient. [•] Matrix (broccoli leaves) had an influence (ion suppression) onto the MS signals. [•] Different glucosinolates content was found in broccoli leaves from six cultivars. [Copyright &y& Elsevier]

Highlights: [•] A fast lipid extraction method (<15min) is introduced by modifying QuEChERS method. [•] Matrix effect of QuEChERS method in lipid analysis is examined using LC-ESI-MS/MS. [•] Applications to human plasma and urine showed useful in lipid identification. [Copyright &y& Elsevier]

Abstract: A simple multiresidue analytical method is developed for the simultaneous determination of carbendazim (CB), thiabendazole (TB), and 6-benzyl aminopurine (6-BA) in bean sprouts. The samples were extracted with acetonitrile followed by partitioning at −80°C for 5–10min. A YMC C8 column was used to separate the analytes before being qualitatively and quantitatively determined by liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS) in positive ion mode using multiple reaction monitoring (MRM). The matrix-matched calibration curves showed good linearity in the range 0.01–1.0mg/kg with correlation coefficients in excess of 0.998. The mean recoveries were in the range of 80.4–96.3% at 0.1 and 0.5 spiked levels, and the relative standard deviations (RSDs) were in the range of 0.5–7.6%. The limits of quantifications (LOQ) were in the range of 0.005–0.01mg/kg. The method was successfully applied to 90 samples (among which 45 were organic) collected from a commercial bean sprout production house throughout the city. Except for 6-BA, the rest of the analytes had values lower than their LOQs. In sum, carbendazim, thiabendazole, and 6-BA were extracted in a single step, and no steps for clean-up or concentration of the extracts were needed. The current method can be used for sensitive and accurate determination and confirmation of residues in bean sprout samples. [Copyright &y& Elsevier]

Abstract: A Quick Easy Cheap Effective Rugged and Safe (QuEchERS) extraction was developed and followed by selective analysis using a liquid chromatography–mass spectrometry method for the quantification of eighteen pesticides in vegetable samples. This method was accurate (⩾99.5%), and it exhibited limits of detection and quantification values in the 0.006–0.091 and 0.020–0.314μgkg−1 ranges, respectively. Furthermore, the coefficients of variations (⩾0.9999) were less than 1% at the low μgkg−1 end of the method. Mean recoveries ranged between 94% and 102%, and relative standard deviations were below 10%. Based on these results, the methodology was proven to be highly efficient, robust, and suitable for monitoring the maximum residue limits (MRL) compliance of a wide range of commodity/pesticide combination. This method was successfully applied to the analysis of vegetable samples that were collected from different government farmers’ markets and street shops in urban areas. The presence of target pesticides was found in the range of 0.016 and 50.85μgkg−1. [Copyright &y& Elsevier]

Abstract: A selective and sensitive LC–MS/MS method was developed and validated for the simultaneous determination of five constituents (cimicifugoside H-2, cimicifugoside H-1, 23-epi-26-deoxyactein, cimigenol xyloside and 25-O-acetylcimigenoside) of Cimicifuga foetida L. in beagle dog plasma. The quantitation was performed on a LC–MS/MS with negative electrospray ionization in selected reaction monitoring (SRM) mode. A gradient mobile phase composed of methanol and water was used at a flow rate of 0.4ml/min. All the analytes and internal standard (20 (S)-ginsenoside Rg3) were isolated from plasma samples by a liquid–liquid extraction method. The average extraction recoveries were 73–74% for cimicifugoside H-2, 89–94% for cimicifugoside H-1, 73–80% for 23-epi-26-deoxyactein, 89–91% for cimigenol xyloside, 87–96% for 25-O-acetylcimigenoside, respectively. The method showed good linearity and no endogenous material interfered with all the five compounds and I.S. peaks. The lower limit of quantification (LLOQ) of all analytes was 0.5ng/ml. The intra- and inter-day precision of analysis was less than 15% for each analyte at concentrations of 2.0, 50, 500ng/ml, and the accuracy ranged from 85.8% to 107%. This method was successfully applied to reveal the pharmacokinetic properties of cimicifugoside H-2, cimicifugoside H-1, 23-epi-26-deoxyactein, cimigenol xyloside and 25-O-acetylcimigenoside after oral administration. [Copyright &y& Elsevier]

Abstract: A simple and sensitive high performance liquid chromatography method with photodiode array detection (HPLC-DAD) was developed for simultaneous determination of eight bioactive constituents (schisandrin, schisandrol B, schisantherin A, schisanhenol, anwulignan, deoxyshisandrin, schisandrin B and schisandrin C) in the ripe fruit of Schisandra sphenanthera and its traditional Chinese herbal preparations Wuzhi-capsule by optimizing the extraction, separation and analytical conditions of HPLC-DAD. The chemical fingerprint of S. sphenanthera was established using raw materials of 15 different origins in China. The chromatographic separations were obtained by an Agilent Eclipse XDB-C18 reserved-phase column (250mm×4.6mm i.d., 5μm) using gradient elution with water–formic acid (100:0.1, v/v) and acetonitrile, at a flow rate of 1.0mLmin−1, an operating temperature of 35°C, and a wavelength of 230nm. The constituents were confirmed by (+) electrospray ionization LC–MS. The new method was validated and was successfully applied to simultaneous determination of components in 13 batches of Wuzhi-capsule. The results indicate that this multi-component determination method in combination with chromatographic fingerprint analysis is suitable for quantitative analysis and quality control of S. sphenanthera. [Copyright &y& Elsevier]

Abstract: A qualitative and quantitative method for the analysis of drugs of abuse (cocaine and benzoylecgonine, opiates) and some stimulants in human hair was developed and validated. Hair samples were incubated with phosphate buffer (pH 5.0), chosen as the extraction medium, extracted with Bond Elut Certify cartridges and analyzed by LC–MS–MS and LC–MS3 as confirmation for positive results. The method proved to be specific, accurate and precise across the calibration range (0.1–30ng/mg) where good linearity was observed. Total extraction recovery, intra-assay accuracy and precision, limits of detection and limits of quantitation were estimated. The method was successfully applied to the analysis of hair samples collected from drug abusers and it was suitable for routine analytical applications in the Antidoping Laboratory of Public Health Laboratory. [Copyright &y& Elsevier]

Abstract: A simple and sensitive method for the determination of patulin in fruit juice and dried fruit samples was developed using a fully automated method consisting of in-tube solid-phase microextraction (SPME) coupled with liquid chromatography–mass spectrometry (LC–MS). Patulin was separated within 5min by high-performance liquid chromatography using a Synergi MAX-RP 80A column and water/acetonitrile (80/20, v/v) as the mobile phase. Electrospray ionization conditions in the negative ion mode were optimized for MS detection of patulin. The pseudo-molecular ion [M−H]− was used to detect patulin in selected ion monitoring (SIM) mode. The optimum in-tube SPME conditions were 25 draw/eject cycles of 40μL of sample using a Carboxen 1006 PLOT capillary column as an extraction device. The extracted patulin was readily desorbed from the capillary by passage of the mobile phase, and no carry-over was observed. Using the in-tube SPME LC–MS with SIM method, good linearity of the calibration curve (r =0.9996) was obtained in the concentration range of 0.5–20ng/mL using 13C3-patulin as an internal standard, and the detection limit (S/N=3) of patulin was 23.5pg/mL. The in-tube SPME method showed >83-fold higher sensitivity than the direct injection method (10μL injection volume). The within-day and between-day precision (relative standard deviations) were below 0.8% and 5.0% (n =6), respectively. This method was applied successfully for the analysis of fruit juice and dried fruit samples without interference peaks. The recoveries of patulin spiked into apple juice were >92%, and the relative standard deviations were <4.5%. Patulin was detected at ng/mL levels in various commercial apple juice samples. [Copyright &y& Elsevier]

Abstract: A simple, rapid and reliable method was developed for the quantification of oxymatrine (OMT) and its metabolite matrine (MT) in beagle dog plasma using a liquid–liquid extraction procedure followed by liquid chromatography–electrospray ionization mass spectrometric (LC–ESI-MS) analysis. Extend-C18 column (2.1mm i.d.×50mm, 5μm) with a C18 guard column (2.1mm i.d.×12.5mm) was used as the analytical column. Linear detection responses were obtained for OMT concentration ranging from 5 to 4000ng/ml and for MT concentration ranging from 5 to 2000ng/ml. The precision and accuracy data, based on intra- and inter-day variations over 5 days, were lower than 5%. The limit of quantitation for OMT and MT were 2 and 1ng/ml, respectively, and their recoveries were greater than 90%. Pharmacokinetic data of OMT and its active metabolite MT obtained with this method following a single oral dose of 300mg OMT capsules to six beagle dogs was also reported for the first time. [Copyright &y& Elsevier]

In Morocco, the recovery of olive agro-industrial by-products as potential sources of high-added value substances has been underestimated so far. A comprehensive quantitative characterization of olive leaves' bioactive compounds is crucial for any attempt to change this situation and to implement the valorization concept in emerging countries. Thus, the phenolic fraction of olive leaves of 11 varieties ('Arbequina', 'Hojiblanca', 'Frantoio', 'Koroneiki', 'Lechín', 'Lucque', 'Manzanilla', 'Picholine de Languedoc', 'Picholine Marocaine', 'Picual' and 'Verdal'), cultivated in the Moroccan Meknès region, was investigated. Thirty eight phenolic or related compounds (including 16 secoiridoids, nine flavonoids in their aglycone form, seven flavonoids in glycosylated form, four simple phenols, one phenolic acid and one lignan) were determined in a total of 55 samples by using ultrasonic-assisted extraction and liquid chromatography coupled to electrospray ionization-ion trap mass spectrometry (LC-ESI-IT MS). Very remarkable quantitative differences were observed among the profiles of the studied cultivars. 'Picholine Marocaine' variety exhibited the highest total phenolic content (around 44 g/kg dry weight (DW)), and logically showed the highest concentration in terms of various individual compounds. In addition, chemometrics (principal components analysis (PCA) and stepwise-linear discriminant analysis (s-LDA)) were applied to the quantitative phenolic compound data, allowing good discrimination of the selected samples according to their varietal origin. [ABSTRACT FROM AUTHOR]