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Separation, identification and quantification of polyphenols was carried out on leaves of Pistacia lentiscusL., an evergreen member of the family Anacardiaceae, using semi‐preparative HPLC, HPLC‐photodiode array detection and HPLC‐MS analysis, together with 1H‐ and 13C NMR. Three major classes of secondary metabolites were detected: (i) gallic acid and galloyl derivatives of both glucose and quinic acid; (ii) flavonol glycosides, i.e. myricetin and quercetin glycosides; and (iii) anthocyanins, namely delphinidin 3‐O‐glucoside and cyanidin 3‐O‐glucoside. Low amounts of catechin were also detected. The concentration of galloyl derivatives was extremely high, representing 5.3% of the leaf dry weight, and appreciable amounts of myricetin derivatives were also detected (1.5% on a dry weight basis). These findings may be useful in establishing a relationship between the chemical composition of the leaf extract and the previously reported biological activity of P. lentiscus, and may also assign a new potential role of P. lentiscustissue extracts in human health care. Copyright © 2002 John Wiley & Sons, Ltd.

In traditional medicine the fresh leaves and juice of Sedum telephium L.are used as wound‐healing promoters. Cell adhesion represents a primary event in wound repair and in tissue homeostasis, and therefore we have investigated the effect of Sedum juice and its main fractions, polysaccharides and flavonols, on human fibroblast (MRC5) adhesion to fibronectin and laminin.

In traditional medicine the fresh leaves and juice of Sedum telephium L.are used as wound-healing promoters. Cell adhesion represents a primary event in wound repair and in tissue homeostasis, and therefore we have investigated the effect of Sedum juice and its main fractions, polysaccharides and flavonols, on human fibroblast (MRC5) adhesion to fibronectin and laminin.Our findings revealed that total Sedum juice strongly inhibited cell adhesion to laminin and fibronectin (EC50 1.03 ± 0.12 mg mL−1). This anti-adhesive feature was concentrated mainly in the two polysaccharide fractions (EC50 values comprised between 0.09 and 0.44 mg mL−1). The flavonol fractions did not seem to contribute to this effect.A first attempt to elucidate the polysaccharide-related anti-adhesive feature of Sedum juice was also performed.The results confirmed that natural polysaccharides, with chemical structures different from heparin, were able to interfere with integrin-mediated cell behaviour and they contributed to the outstanding effects of Sedum juice and to the role of polysaccharides in cell-matrix interaction.

Vitamin C acts as a powerful radical scavenger, and can be used as a convenient antioxidant agent in aqueous media. To extend its properties to nonaqueous environments, alkanoyl-6-O-ascorbic acid esters with different chain lengths were synthesized, and their micellar and antioxidant properties were investigated by surface tension, viscosity, light scattering, neutron scattering, oxygen uptake, and UV/VIS spectra. According to our results, octanoyl-ascorbic acid forms nearly spherical micelles in water solutions above a cmc of about 6 × 10^-3 mol/L at 30 °C, while decanoyl- and dodecanoyl-ascorbic acid are poorly soluble in water. No matter how long the hydrophobic chain is, all these esters show the same antioxidant activity as vitamin C and other natural products.

Summary: Liquid-liquid (LLE) and liquid-solid extraction (LSE) procedures were developed to identify polyphenols in phillyrea (Phillyrea angustifolia L.) leaves. The liquidsolid extraction, carried out by using two serial Bond-Elut® CH and Bond-Elut® SAX cartridges allowed the collection of both polyphenols and soluble carbohydrates during a single extraction of leaf. This method seems to be suitable for both phytochemical and physiological study of the species, allowing the identification of two classes of organic compounds which have a central role in the metabolism of phillyrea plants. A method of isolation and concentration of polyphenols for further molecular characterization, using centrifuge chromatography, was also developed. Molecular characterization, carried out by UV-Vis spectrophotometry and mass spectrometry, demonstrated the presence of compounds with interesting biological activity, i.e. flavonoids and oleuropein derivatives. The soluble carbohydrate composition of phillyrea leaves did not substantially differ from that ofOlea europaea L. leaves, except for a higher mannitol/glucose ratio. This carbohydrate distribution may be linked to the evolution pattern of this species which usually grows in severely stressed environments.

Capillary zone electrophoresis (CZE) with multi-wavelength detection has been used for the separation of the main alkaloids fromEschscholtzia californica. Optimum separation has been achieved with a fused silica capillary tube and a running electrolyte at pH 2.8 prepared from a 40 mM solution of citric acid and a 80 mM solution of Na2HPO4. The applied voltage was 20 kV and the capillary thermostating temperature was kept constant at 10°C.

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