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A fast and accurate methodology for the quantification of the most abundant flavanone glycosides in citrus beverages has been developed. The approach relies on the use of paper spray mass spectrometry, which allows to record data in few minutes and without sample pre-treatment. The experiments have been carried out in Multiple Reaction Monitoring scan mode, in order to obtain the best specificity and sensitivity. The analytical parameters were all satisfactory. The results coming from the analysis of real samples were compared to the data obtained by the commonly used chromatographic method, proving the robustness of the proposed approach.

In this article, we aimed to investigate the anti-aging activity of Lantana camara ethanolic leaves-extract in Drosophila melanogaster: survival and longevity (life span). L. camara leaves were collected and washed thoroughly of sand particles, air-dried, ground, and extracted by the maceration method using ethanol as a solvent. Phytochemical screening was carried out. 168-hour LC50 was determined by exposing fruit flies to concentrations ranging from 5 to 5000 mg/10 g diet for 7-days. Twenty-eight-day survival and longevity studies were carried out by administering L. camara ethanolic leaves extract at 5, 10, and 20 mg/10 g diet to 1–3 days old fruit flies. Each concentration was replicated four times with 50 fruit flies each. The emergence rate of young fruit flies from eggs laid by fruit flies administered L. camara leaves-extracts were also carried out. The total yield of the extraction was determined to be 18%. Phytochemical analysis revealed the presence of alkaloids, Flavonoids, Phenol, steroids, cardiac glycosides, and carbohydrates. 168-hour LC50 of L. camara was also determined to be 1135 mg/10 g diet. L. camara significantly prolonged (P

Instituto de Recursos Naturales y Agrobiología, CSIC, P.O. Box 1052, 41080 Seville, Spain, The chemical composition of lignin and lipids of bast fibers from industrial hemp (Cannabis sativa) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with a p-hydroxyphenyl:guaiacyl:syringyl unit (H: G:S) molar proportion of 13:53:34 (S/G ratio of 0.64). p-Hydroxycinnamic acids, namely, p-coumaric and ferulic acids, were found in only trace amounts. Among the lipids, the main compounds identified by GC/MS of the hemp fibers extracts were series of n-alkanes, free and esterified sterols and triterpenols, waxes, and long-chain n-fatty acids. Other compounds such as n-aldehydes, n-fatty alcohols, steroid hydrocarbons, and steroid and triterpenoid ketones as well as steryl glycosides were also found., This study has been supported by the Spanish Ministerio de Ciencia y Tecnología (MCyT) and FEDER funds (Projects AGL2002-00393).

Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC, P.O. Box 1052, E- 41080 Seville, Spain E-mail address: delrio@irnase.csic.es (J.C. del Río), The chemical composition of leaf fibers of abaca (Musa textilis), which are commonly used for high-quality paper pulp production, was thoroughly studied. The results revealed that the lignin content was 13.2 % of the total fiber. The analysis of abaca fibers by Pyrolysis coupled to gas chromatography-mass spectrometry (Py-GC/MS) released predominantly compounds arising from lignin and p-hydroxycinnamic acids, with high amounts of 4-vinylphenol. The latter compound was demonstrated to arise from p-coumaric acid by pyrolysis of abaca fibers in the presence of tetramethylammonium hydroxide (TMAH), which released high amounts of p-coumaric acid (as the methyl derivative). Products from p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) propanoid units, with a predominance of the latter (H:G:S molar ratio of 1.5:1:4.9) were also released after Py-GC/MS of abaca fibers. Sinapyl and coniferyl acetates, which are thought to be lignin monomer precursors, were also found in abaca. The extractives content of the abaca fiber (0.4 %) was low, and the most predominant compounds were free sterols (24% of total extract) and fatty acids (24% of total extract). Additionally, significant amounts of steroid ketones (10%), triglycerides (6%), ω-hydroxyfatty acids (6%), monoglycerides (4%), fatty alcohols (4%) and a series of p-hydroxycinnamyl (p-coumaric and ferulic acids) esterified with long chain alcohols and ω-hydroxyfatty acids were also found, together with minor amounts of steroid hydrocarbons, diglycerides, α-hydroxyfatty acids, sterol esters and sterol glycosides., This study has been supported by the Spanish Ministerio de Ciencia y Tecnología (MCYT) (projects AGL2002-00393 and AGL2005-01748). We thank Isabel M. Rodríguez for sample preparation and technical support. We also thank J.M. Gras and G. Artal (CELESA, Spain) for providing the abaca leaf fibers.

Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC, P.O. Box 1052, 41080-Seville, Spain; E-mail address: delrio@irnase.csic.es (J.C. del Río), The chemical composition of lignin and lipids of bast fibers from kenaf (Hibiscus cannabinus) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with high syringyl:guaiacyl ratio (5.4) and minor amounts of p-hydroxyphenyl units. Simultaneously, sinapyl and coniferyl acetates were also identified, indicating that this lignin is partially acetylated. p-Hydroxycinnamic acids were only found in trace amounts. The main lipids identified by GC/MS of extracts from kenaf fibers were series of long chain n-fatty acids, waxes, n-alkanes and n-fatty alcohols. Free and esterified sterols and triterpenols, steroid hydrocarbons, steroid and triterpenoid ketones, as well as steryl glycosides were also found. Finally, the fate of the main constituents of kenaf fibers in alkaline pulping was also investigated., This study has been supported by the Spanish Ministerio de Ciencia y Tecnología (MCyT) and FEDER funds (project AGL2002-00393). A.G. acknowledges a "Ramón y Cajal" contract of the Spanish MCyT. We thank CELESA (Tortosa, Spain) for providing the kenaf and pulp samples, S. Camarero (CIB, CSIC, Madrid) for Klason lignin and hemicellulose analyses and A. T. Martínez (CIB, CSIC, Madrid) for critical reading of the manuscript.