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In this paper several approaches are discussed for the direct analysis of the main sugars in different fruit juices. Refractometry, thin layer chromatography, volumetric analysis and high performance liquid chromatography with refractive index detector were tested and the results compared, discussing the advantages and disadvantages of each of them. Whereas the first method gives generically indications on the whole content of sugar and it doesn’t require any prior manipulation of the sample, thin layer chromatography is useful only for qualitative purpose, on the other hand the third method, after removal of interferences, makes possible the determination of the reducing and not reducing sugar, and the last one allows the qualitative and quantitative determination of the saccharides singularly. It’s very important to have not only knowledge about the chemical analysis of carbohydrates and their physicochemical properties, but especially how the methods can be used in product development for benefit of the public. In the wide range of options for the determination of the mono and disaccharides in beverages, the approach selected must be robust, accurate, powerful and reproducible.

In this paper, we report a simple method for the determination of quercetin, a typical antioxidant compound ubiquitously present in vegetable food products including grapes and wine. To this aim, 12 Italian wines were analyzed and the amount of quercetin was determined by high-performance liquid chromatography with ultraviolet detector. To reduce the interferences, a minimal sample preparation was performed on solid phase cartridge, then the samples were eluted through a narrow bore C18 column under gradient elution in less than 25 min. Nine wines were red and three white. The amount of quercetin ranged from 0.5 to 4.3 mg L−1. The method was evaluated in terms of reproducibility, linearity, recovery, and limits of detection and quantification, and it resulted relatively fast, economical, and suitable for those laboratories involved in routine analysis. In addition, the possibility to determine the content of quercetin derivates, as free quercetin, after acidic hydrolysis was investigated. Despite the limited number of analyzed samples, the results from this explorative study are in agreement to those from other surveys. Moreover, due to the problems arising from hydrolysis, further research are needed for determining each single quercetin derivate in wine, in order to better characterize its active compounds.

Potential harmful effects of pesticides include risks to human health of workers involved in the wet spray application in cultivated areas. Inhalation exposure depends on several factors including ...

Airborne microorganisms, as bacteria and fungi, are ubiquitous components of the atmospheric aerosol particles. In this paper, we report a method for the simultaneous extraction, purification, separation, identification and quantification of ergosterol, mannitol and arabitol as biomarkers of fungal spores in bioaerosol particles. After sampling by a low volume sampler, filters were spiked with mannitol-13C and dehydrocholesterol as internal standards. Samples were then extracted by accelerated solvent extraction using pure ethanol. The extract was then passed through an amino cartridge and divided in two parts: the apolar fraction, released from the cartridge, was subjected to liquid liquid extraction (by n-hexane), while polar compounds, retained by the cartridge, were eluted by a mixture of methanol–water. The two fractions were joined and analyzed by HPLC equipped with two different columns in series, and coupled to a triple-quadrupole mass spectrometer with Atmospheric Pressure Chemical Ionization source. In addition, the same fractions were analyzed, after derivatization, by GC–MS. The results obtained by the two techniques were finally compared, showing good agreement between them. Last, the contents of the three biomarkers have been estimated in three atmospheric samples collected in a suburban/rural site and, using literature conversion factors, correlated to fungal biomass.

Avermectines are antiparasitic agents widely used as veterinary drugs for food producing animals. The European Community, due to their side effects, limited the use of these molecules establishing maximum residue limits (MRLs) in some foods. A validated qualitative and quantitative high performance liquid chromatography method with fluorescence detection (HPLC-FL) is presented for the simultaneous determination of ivermectin (IVM), abemectin (ABA), moxidectin (MOX), eprinomectin (EPR), doramectin (DOR) and emamectin (EMA) in foodstuffs (muscle, eggs and milk). Samples were extracted with acetonitrile, purified with liquid-liquid extraction (LLE), and analysed by HLPC-FL previous derivatization with trifluoroacetic anhydride (TFAA) in presence of 1-methyl-imidazole (MI) and acetic acid. To date, the presented method is the first validated for the matrix eggs, and in accordance with the requirements set by Commission Decision 2002/657/EC. Recoveries of the methods, calculated spiking the samples in the range 5.0–100.0 μg kg −1 , were 64–83% for muscle, 65–89% for milk and 63–84% for eggs. The precision (CV) ranged between 9.2 and 17.1% for muscle, 9.9 and 16.6% for milk and from 9.4 to 17.4% for eggs. Linearity for the six analytes was calculated from 5.0 to 200.0 μg kg −1 . The main advantages of the presented method are its rapidity, the specificity, the good precision and recovery that make it very suitable to the detection and determination of avermectines.

Resveratrol (3,5,4′-trihydroxystilbene) is a phytoalexin that belongs to the group of stilbenes, known to occur in grapes and consequently in grape products. Its presence in wine is an important qualitative parameter because of the several beneficial effects on human health. The aim of this work is the development of a high-performance liquid chromatographic (HPLC) method for the determination of trans resveratrol in wines, and comparisons between the results obtained by different detection techniques: UV-vis spectroscopy, fluorescence spectroscopy and mass spectrometry. Resveratrol is analysed on a C-18 column using gradient elution. The method permits direct injection of sample, revealing to be time-saving, overcoming the need of sample pre-treatment steps. Detection limits were 154.8 ng mL−1 by HPLC-UV, 118.0 ng mL−1 by HPLC-FL and 48.0 ng mL−1 by HPLC-MS. Trans resveratrol has been then quantified in a group of 52 wines derived from different Italian regions, cultivars and winemaking technologies by HPLC-UV.

Boldenone is an androgenic anabolic steroid (AAS) intensively used for growth promoting purposes in animals destined for meat production and as a performance enhancer in athletics. Therefore its use is officially banned either in animals intended for consumption or in humans. Because most anabolic steroids are completely metabolized and usually no parent steroid is excreted, metabolite identification is crucial to detect the illegal use of anabolic steroids either in humans or in livestock. The aim of this work is the investigation of 17-boldenone and its main metabolites, 17-sulphate, 17-glucuronide, 5-androst-1-en17-ol-3-one and 17-boldenone, in human and bovine urine developing a multiresidue analysis. After solid phase extraction of urine samples, detection is carried out by high performance liquid chromatography–tandem mass spectrometry in multiple reaction monitoring. The average recovery for all the investigated compounds is above 70%. The developed method is very easy, quick and highly specific. Linearity, precision, decision limit and detection capability were also evaluated. © 2005 Elsevier B.V. All rights reserved.

In this work several compounds were detected in wines by HPLC-tandem mass spectrometry. In particular cinnamic and benzoic acids, tyrosol, apigenin-7-glucoside and luteolin-7-glucoside were identified and quantified in Italian wines. Red wines show bigger amount of cinnamic and benzoic acids than white wines. tyrosol is in bigger amount with respect to two flavones: luteolin-7-glucoside and apigenin-7-glucoside. These last two flavones are only in some wine, but it can be important to detect the presence of different substances in small amount to be able to characterize a wine.

Corticosteroids can be illegally administered to cattle as growth promoting agents to improve meat production. We developed a liquid chromatography-atmospheric pressure ionization mass spectrometry-mass spectrometry (LC-MS-MS) method able to identify and quantify flumethasone, one of the most potent fluorinated synthetic corticosteroid, in serum and urine from treated calves. The analyte was purified from urine (conjugated and free, following enzymatic hydrolysis) and from serum by C18 solid-phase and liquid-liquid extractions, then analyzed by LC-MS-MS monitoring the product ions of an abundant precursor (SRM in negative ionization mode). Results on flumethasone residues in biological fluids in three calves treated at different levels are presented. This method allowed the detection of flumethasone in bovine urine and serum at the 30-pg/ml level.

The aim of this work was to analyze by HPLC-MS-MS natural biophenolic compounds in complex natural samples like olives and olive oils. Eleven benzoic and cinnamic acids, vanillin and other eight bi...

In this work hydroxycinnamic acid esters of tartaric acid (mono-p-coumaroyl tartaric acid, monocaffeoyl tartaric acid, monoferuloyl tartaric acid esters) were separated, identified and quantified in several red wines by high performance liquid chromatography coupled with tandem mass spectrometry. The method features direct analysis of wines with no preparation and analysis of grape juice with minimum sample manipulation. For the identification was used both a triple quadrupole and a quadrupole–Tof, while for the quantification a triple quadrupole. At the same time two impurities, due to interfering substances coming from methanol (stored in bottles with polypropylene tops without Teflon protection), were characterised. These impurities had the same molecular weight as the investigated compounds.

Some citrus essential oils were analyzed by HPLC with both microbore and standard columns in reversed and normal phase. Volatile and non-volatile fraction were investigated. In the non-volatile fraction some coumarins have been identified. Fractions are detected spectrophotometrically at 220 nm and 320 nm before and after evaporation of samples. Some components were also identified by LC/MS.

Stilbenes from grapes and wines play a central role in the human diet because of their antioxidant, antimutagenic and anticarcinogenic properties. We describe a method for the direct determination of some stilbenes (cis- and trans-resveratrol, cis- and trans-resveratrol glucoside, cis- and trans-piceatannol, and cis- and trans-piceatannol glucoside) in wine by high-performance liquid chromatography/mass spectrometry using a triple quadrupole (QqQ) mass spectrometer, in multiple reaction monitoring (MRM) mode, acquiring two diagnostic product ions from the chosen precursor. All the target analytes were separated on a C-18 column using gradient elution, in a single run. Electrospray ionization (ESI) in negative ion mode gives higher sensitivity for all the target compounds than atmospheric pressure chemical ionization (APCI). For the identification of piceatannol glucoside (astringin), because of the lack of a suitable standard, an HPLC/TOFMS method was used. The method permits direct injection of samples and it is time-saving, removing the need for sample pre-treatment. The detection limits were 48.0 ng mL(-1) for cis- and trans-resveratrol and for cis- and trans-resveratrol glucoside, and 50.0 ng mL(-1) for cis- and trans-piceatannol. The procedure proved to be simple and suitable for routine and confirmatory purposes. A total of 19 red and 3 white Italian wines were analyzed and differences in the stilbene composition were found among these samples.

Biophenolic compounds constitute a complex mixture in olives and derived products. In this work, ion-spray tandem mass spectrometry coupled with liquid chromatography is applied to the identification and quantification of biophenols present in complex matrices such as olives and vegetation waters. The extraction and purification method for the biophenol present in both the matrices is reported. Using this approach the main biophenols found, in three different variety of olives, were: tyrosol, hydroxytyrosol, oleoside methyl ester, oleoside dimethyl ester, and oleuropein. In vegetation water the biophenols are present in lower amounts than in olives.

In this study the qualitative and quantitative content of the biophenolics in virgin olive oils is evaluated by liquid chromatography-tandem mass spectrometry. The extraction and purification method for these compounds from virgin oils was optimised. After liquid-liquid and solid-phase extraction the separation of 35 of these compounds was achieved on reversed phase in gradient mode. The detection was preliminarily by UV and fluorescence, but then the final choice was ion-spray tandem mass spectrometry in multiple reaction monitoring mode in negative ionization, acquiring two diagnostic product ions from the chosen precursor [M—H]–. Using this last approach we obtained the best sensitivity, selectivity, and specificity. The recovery of the method ranged from 70–90% and detection limits were less than 1 ng for all the analyzed compounds.

The analysis of bitter orange and grapefruit essential oils (non-volatile fraction) was carried out by HPLC in normal- and reversed-phase mode with UV detection. These oils were compared with the sweet orange and mandarin essential oils, analyzed previously. For the identification of chromatographic peaks, fractionation by RP-HPLC was carried out. The purified fractions were analyzed by GC-MS and LC-MS. Some new compounds were found, together with many others already identified in different citrus essential oils.

A method for the extraction and separation of the non-volatile phenolic acids of wine is described. The extracts are analysed by HPLC with a microbe column and UV detection. The free phenolic acids and depsides in different wine samples were identified and determined.

The analysis of orange and mandarin essential oils (nonvolatile fraction) was carried out by HPLC in normal and reverse phase modes with UV and spectrofluorimetric detection in series.