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Abstract: Hydroxytyrosol and tyrosol, the strong antioxidant present in large amount in virgin olive oil have been assayed by LC–MS/MS under MRM condition and isotope dilution method, using d 2-labelled internal standards obtained by simple synthetic procedures. The assay has been performed under MRM condition monitoring two transitions for each analyte to improve the specificity. This paper deals with a modern approach for assaying the content of this polyphenols in virgin olive oil down to a limit of a few hundreds of parts per billion. Tyrosol and hydroxytyrosol ranged from 10 to 47ppm and from 5 to 25ppm in commercial olive oil, respectively. The accuracy (98–107%) and analytical parameters values confirm the reliability of the proposed approach. The method can be extended to any natural matrices, including mill wastes, after a simple step of sample preparation. [Copyright &y& Elsevier]

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 [2l 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. [ABSTRACT FROM AUTHOR]

A rapid analytical method for the determination of phenylethanoids content in extra virgin olive oil has been developed. The method intends to address the European regulation EU 432/2012 on health claims, which allows to report on the front label of olive oil, the positive health effects due to the consumption of this food. The innovative method is based on paper spray tandem mass spectrometry using deuterated standards. It relies on a two-step analysis, needed to assess the free form of tyrosol and hydroxytyrosol and their ester conjugates after hydrolysis treatment. Different olive oil samples have been analyzed and the classical analytical parameters such as accuracy, LOQ and LOD were calculated from fortified samples. The good values of the latters show the reliability of the new approach, that limits the time of analysis and sample preparation to few minutes. • A rapid determination of phenylethanoids in olive oil has been set up. • The whole experiment lasts few minutes. • The analysis utilizes labeled standards and paper spray tandem mass spectrometry. • The method was tested to extra virgin olive oil and fortified oil samples. • The proposed method addresses the European regulation 432/2012 on health claims. [ABSTRACT FROM AUTHOR]

Abstract: A new device for the preparation of stoned olive oils, called SPIA, has been developed, aiming at fulfilling the targets of: (i) employing a less powered engine, (ii) reducing the size of the machine and (iii) reaching a good efficiency in terms of oil yields. Oleuropein expression was used as a biochemical parameter to distinguish stoned oils from oils produced by conventional milling systems. In vitro experiments performed by exposing oleuropein to pit enzymes, showed an exponential decay of the substrate. [Copyright &y& Elsevier]

A fast methodology for the assay of parabens in drug and cosmetic preparations has been presented. The procedure developed is based on paper spray tandem mass spectrometry and isotope dilution approach. For each investigated paraben, the corresponding labeled standard has been used in order to improve the accuracy and reproducibility of the analyses. The MS experiments have been performed under MRM conditions, monitoring the transitions [M‐H]− → m/z 92 and [M‐H]− → m/z 98, respectively, for each analyte and the corresponding labeled internal standard. The quantitative assay has been performed using a calibration curve built from 2 to 15 mg/L. The method accuracy, in all case near 100%, was evaluated using fortified samples at two concentration levels, which are representative of the lower and the higher portion of calibration curve. The good values of LOQ, LOD, and reproducibility confirm the consistency of the developed approach. [ABSTRACT FROM AUTHOR]

A rapid analytical approach for the assay of resveratrol in red wines, based on Paper Spray Mass Spectrometry (PS-MS) and Multiple Reaction Monitoring (MRM) is described. The assay involves the use of the stable isotope dilution method. The analytical parameters calculated analyzing fortified samples confirm the reliability of the proposed approach, with accuracy values about 100%, and LOD and LOQ values calculated at 0.5 and 0.8 μg/mL, respectively. Furthermore, both the recovery, which was quantitative for the analyte, and the reproducibility (RSD%), checked on different days on the same wine, always below 7%, highlighted the consistency of the methodology. [ABSTRACT FROM AUTHOR]