A rapid, simple and sensitive method based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) with an electrospray ionization (ESI) source for the simultaneous analysis of fourteen water-soluble vitamins (B1, B2, two B3 vitamers, B5, five B6 vitamers, B8, B9, B12 and C) in various food matrices, i.e. maize flour, green and golden kiwi and tomato pulp, is presented here. Analytes were separated by ion-suppression reversed-phase liquid chromatography in less than 10 min and detected in positive ion mode. Sensitivity and specificity of this method allowed two important results to be achieved: (i) limits of detection of the analytes at ng g(-1) levels (except for vitamin C); (ii) development of a rapid sample treatment that minimizes analyte exposition to light, air and heat, eliminating any step of extract concentration. Analyte recovery depended on the type of matrix. In particular, recovery of the analytes in maize flour was > or =70%, with the exception of vitamin C, pyridoxal-5'-phosphate and vitamin B9 (ca 40%); with tomato pulp, recovery was > or =64%, except for vitamin C (41%); with kiwi, recovery was > or =73%, except for nicotinamide (ca. 30%).

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Adventitious roots (ARs) are induced by auxins. Jasmonic acid (JA) and methyl jasmonate (MeJA) are also plant growth regulators with many effects on development, but their role on ARs needs investigation. To this aim, we analyzed AR formation in tobacco thin cell layers (TCLs) cultured with 0.01-10 microM MeJA, either under root-inductive conditions, i.e., on medium containing 10 microM indole-3-butyric acid (IBA) and 0.1 microM kinetin, or without hormones. The explants were excised from the cultivars Samsun, Xanthii and Petite Havana, and from genotypes with altered AR-forming ability in response to auxin, namely the non-rooting rac mutant and the over-rooting Agrobacterium rhizogenes rolB transgenic line. Results show that NtRNR1 (G1/S) and Ntcyc29 (G2/M) gene activity, cell proliferation and meristemoid formation were stimulated in hormone-cultured TCLs by submicromolar MeJA concentrations. The meristemoids developed either into ARs and xylogenic nodules, or into xylogenic nodules only (rac TCLs). MeJA-induced meristemoid over-production characterized rolB TCLs. No rooting or xylogenesis occurred under hormone-free conditions, independently of MeJA and genotype. Endogenous JA progressively (days 1-4) increased in hormone-cultured TCLs in the absence of MeJA. JA levels were enhanced by 0.1 microM MeJA, on both days 1 and 4. Endogenous IBA was the only auxin detected, both in the free form and as IBA-glucose. Free IBA increased up to day 2, remaining constant thereafter (day 4). Its level was enhanced by 0.1 microM MeJA only on day 1, while IBA conjugation was not affected by MeJA. Taken together, these results show that an interplay between jasmonates and auxins regulates AR formation and xylogenesis in tobacco TCLs.

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The main difficulties in analysing non-steroidal anti-inflammatory drugs (NSAIDs) in food and biological samples are due to the tight non-covalent interactions established with matrix proteins and the amount of occurring fatty material. The present paper describes an effective extraction procedure able to isolate fifteen NSAIDs (acetaminophen, salicylic acid, ibuprofen, diclofenac, flunixin and its metabolite 5-hydroxy-flunixin, nimesulide, phenylbutazone, meclofenamic acid, tolfenamic acid, meloxicam, carprofen, ketoprofen, naproxen and etodolac) from bovine milk and muscle tissue through two succeeding steps: (a) deproteinisation/extraction with organic solvent, essential to lower the medium dielectric constant and, therefore, to release the analytes from matrix; (b) SPE clean-up on OASIS cartridges. Lipids were easily removed during low-temperature centrifugations. The advantages of the developed procedure pertain to the efficient removal of the fat substances (very low matrix effect and high recovery yields) and its versatility, since it can be applied both to milk and muscle with few adjustments due to the diversity of the two matrices. Ion-pairing reversed-phase chromatography combined with the negative electrospray detection was able to achieve low detection capabilities (CCβs) for all analytes and, in particular, for diclofenac whose Maximum Residue Limit (MRL) in milk is 0.1 μg kg(-1). The methods were validated according to the guidelines of the Commission Decision 2002/657/EC and then applied for a small monitoring study. A number of samples showed traces of salicylic acid (SA), but its occurrence was not ascribed to a misuse of drugs (aspirin, salicylic acid) since SA, accumulating in plants in response to a pathogen attack, may be introduced into the food chain.