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Resveratrol is a phytoalexin found in several plant tissues and present in wines, which is supplied as a nutritional supplement. Different studies have revealed its beneficial effects as anticancer, antiviral, neuroprotective, antiaging, and anti-inflammatory natural active principle. The assaying of resveratrol by mass spectrometry and isotope dilution method, using a stable [[sup.2][H.sub.4] analogue, has required a full elucidation of its gas-phase H/D isotopomerization. Either selected ion monitoring (SIM) or multiple reaction monitoring (MRM) methods have been used for the evaluation of the amount of resveratrol present in wine and plasma samples in the negative ionization mode. In all instances the acquired accuracy, limit of quantitation (LOQ), and limit of detection (LOD) are fit for the intended purpose of the assay. 10.1021/ac9015243

The proteic profiling of bovine milk produced by cows with subclinical mastitis was obtained by MALDI mass spectrometry. A simple procedure of chemical fractionation of raw milk was developed, whereby less complex fractions of proteins were obtained prior to mass spectrometric and SDS-PAGE analysis. The profiles of milk proteins thus obtained could allow the identification of either early markers of the acute phase of mastitis or endogenous peptide of innate immune response. The activity of the endogenous proteases in raw milk produced from each quarter of healthy and mastic cows was therefore assayed over 24-, 48-, 96-, and 216-h incubation at 37 [degress]C at both physiological and acid pH. Sequence-specific peptides were identified for each fraction by MS/MS experiments, and all tandem mass spectra were evaluated using MASCOT database searching. The results show a specific proteolytic activity of endogenous enzyme toward [beta]-casein precursor (P02666), [alpha]-[S.sub.2]-casein (P02663), [alpha]-[S.sub.1]-casein (P02662), and [kappa]-casein (P02668).

The antigenic profile of Olea europaea pollen from different Mediterranean cultivars was obtained by MALDI mass spectrometry. A simple procedure of chemical fractionation of the whole antigen extract was developed, whereby less complex, or pure, fractions of antigen candidate were obtained prior to mass spectrometric analysis. Some of the features of protein structure and distribution probably depend on cultivar adaptation to the environment. The profilings of pollen proteins thus obtained allow the distinction of the analyzed cultivars into three distinct groups: (i) those characterized by a low Ole e 1 content; (ii) those over-enriched in Ole e 1 and (iii) that containing Ole e 3 and Ole e 7 only. The latter consists of at least four isoforms differing by the degree of glycosilation. These results demonstrate that the proposed experimental procedure, can supply valuable information on the antigens' micro heterogeneity.

Oleuropein (OLP, 1), the active ingredient present (i) in food integrators extracted from olive leaves, (ii) in table olives, and (iii) in extra virgin olive oils is a nutraceutical whose health benefits have been widely documented. A new analytical method for its assay, which is based on the utilization of atmospheric pressure chemical ionization tandem mass spectrometry and on the use of a synthetic labeled analogue, the 4-trideuteriocarboxyoleuropein (2), as an internal standard, is presented. The results obtained with extra virgin olive oils from different cultivars and different Italian regions are discussed.

2,7-Dimethoxynaphthalene (DMN) is proposed as matrix to investigate the structure of polymetallic porphyrins through matrix-assisted laser desorption/ionization tandem time-of-flight experiments. The peculiarity of DMN is represented by the formation of molecular radical cations and of some diagnostic fragments only. The traditional matrixes do not afford the expected molecular species. The experiments have been performed on extremely labile species such as zinc porphyirinate complexes with aluminum and gallium quinolinate to prove the softness of the methodology.

Food safety represents one of the main issues of national and international agencies appointed to health control. In April 2003, a French agency disclosed that powdered or smashed hot chili pepper imported from India and Pakistan was heavily contaminated with a carcinogenic azo dye known as Sudan I. This paper deals with a modern approach for assaying the content of this colorant in foodstuff down to a limit of a few tens of parts per billion. The isotope dilution method combined with APCI tandem mass spectrometry was used. The internal standard, 1-([d.sub.5]-phenylazo)-2-naphthalenol, was obtained by simple chemistry, and its structure was determined by [sup.1]H NMR spectroscopy. The mass spectrometric method is more sensitive than the HPLC approach by a factor of 20.