WASTE-WATERS FROM OLIVE OIL PRODUCTION ARE RICH IN NATURAL ANTIOXIDANTS

Milling of olive paste during olive oil production is accompanied by continuous washing with water, i.e. malaxation. The resulting 'waste-water' is currently discarded. Since olives and olive oil are rich in natural antioxidants, we hypothesized that some of these might be extracted from the olive paste during malaxation, Interest in natural antioxidants is increasing because of the growing body of evidence indicating the involvement of oxygen-derived free radicals in several pathological processes, such as cancer and atherosclerosis. A waste-water extract was characterized by HPLC and tested in a model of lipid peroxidation, copper sulphate-induced oxidation of low density lipoproteins. The results demonstrate that waste-water extracts have powerful antioxidant activity and might therefore represent a cheap, as yet unused, source of natural antioxidants

Simultaneous analysis of artemisinin and flavonoids of several extracts of Artemisia annua L. obtained from a commercial sample and a selected cultivar

Arteirtisia annua L. (Qinghao) is a promising and potent antimalarial herbal drug. This activity has been ascribed to its component artemisinin, a sesquiterpene lactone that is very effective against drug-resistant Plasmodium species with a low toxicity. Our studies indicate that several flavonoids of A. annua can promote and enhance the reaction of artemisinin with hemin. These data are in good agreement with previous investigations on the in vitro potentiation of antimalarial activity of artemisinin by such flavonoids. As a consequence, in view of a possible use of the phytocomplex rather than pure artemisinin, an HPLC/DAD/MS method is proposed for the simultaneous detection and quantification of both flavonoids and artemisinin. Different extracts, obtained from two different herbal drugs, a commercial sample and a selected cultivar, were analyzed in order to determine which solvents provide the best yields of both artemisinin and flavonoids. Qualitative and quantitative results obtained using an HPLC method are described, which will be useful for developing highly effective herbal drug preparations. (c) 2006 Elsevier GmbH. All rights reserved.13748749

Olive-oil Phenolics and Health: Potential Biological Properties

Extra virgin olive oil, the primary source of oil in the Mediterranean diet, differs significantly in composition from dietary lipids that are consumed by other populations. The several minor constituents of virgin olive oil include vitamins such as alpha- and gamma-tocopherols (around 200 ppm) and beta-carotene, phytosterols, pigments, terpenic acids, flavonoids, squalene, and a number of phenolic compounds, such as hydroxytyrosol, usually grouped under the rubric "polyphenols". The antioxidant and enzyme-modulating activities of extra virgin olive oil phenolics, such as their ability to inhibit NF-kappa B activation in human monocyte/macrophages has been demonstrated in vitro. There is also solid evidence that extra virgin olive oil phenolic compounds are absorbed and their human metabolism has been elucidated. Several activities that might be associated with cardiovascular protection, Such as inhibition of platelet aggregation and reduction of plasma rHcy have been demonstrated in vivo. The biologically relevant properties of olive phenolics are described, although further investigations in controlled clinical trials are needed to support the hypothesis that virgin olive oil consumption may contribute to lower cardiovascular mortality

Cyclodextrins as carriers for kavalactones in aqueous media: Spectroscopic characterization of (S)-7,8-dihydrokavain and ß-cyclodextrin inclusion complex

Kavalactones represent the active constituents of kava–kava (Piper methysticum G. Forster),endowed with sedative and anaesthetic properties. Kavalactones are polar constituents, but poorly soluble in water with a low bioavailability. In this study, the formation of inclusion complexes of one of the most representative avalactone isolated from kava–kava extract, (S)-7,8-dihydrokavain (DHK), with beta-cyclodextrin (beta-CyD) was investigated mainly by spectroscopic methods. NMR experiments were extensively used for the complete characterization of the complex and included 1H NMR complexation shifts analysis, 1H NMR diffusion measurements (DOSY), and ROESY experiments. In particular DOSY experiments demonstrated that in the presence of beta-CyD the translational diffusion of kavalactone is sizably slowed down (2.5×10−10m2/s) with respect to the free drug (4.4×10−10m2/s) according to the inclusion of DHK in the cavity of beta-CyD. ROESY experiments confirmed the inclusion of DHK in the hydrophobic pocket of beta-CyD through the primary hydroxyl rim, being the most relevant interactions between the H3' of beta-CyD and the ortho protons on the phenyl ring of the DHK, and between H5' of beta-CyD and the meta/para protons of DHK phenyl ring. The inclusion of the phenyl ring of DHK, leaving the lactone moiety outside of CyD was also confirmed by the induced CD effects. The binary solution DHK/beta-CyD shows a 50% intensity increase of the negative band of the pi–pi* transitions of the phenyl ring with respect to the absorption observed with DHK alone. Molecular dynamics simulations results corroborated and further clarify observed spectroscopic data. It was found that the phenylethyl substituent at C6 has a preferential equatorial position in the free state, and an axial one in the complex, justifying the large downfield shift experienced by H6 of DHK upon binding. Finally the influence of beta-CyD on water solubility of DHK was investigated by phase-solubility studies. In the range 2–4mM of host, solubility of DHK was increased only two-fold, but being beta-CyD also a penetration enhancer, in vivo studies will be performed to clarify a possible role of the complex on the bioavailability of DHK

Studies on the interactions between some flavonols and cyclodextrins

The interactions of some natural flavonols with alpha, beta- and gamma-Cds have been investigated. Guest molecules were galangin, kaempferol and quercetin. Inclusion complexes were prepared by kneading and freeze-drying. The complexes were characterized using different physico-chemical methods based on differential scanning calorimetry (DSC), infrared spectroscopy (IR) and NMR spectroscopy. In the proton and carbon spectra the effects of complexation on the chemical shifts of the internal and external protons of Us in the presence of each flavonoid were observed. Moreover, the water-solubility of the flavonols in the presence of Us was also evaluated. The increased solubility of quercetin and kaempferol in the presence beta-Cd was evidenced. For all three guests, multidimensional NMR experiments in DMSO and water are consistent with dynamic binding processes, dominated by insertion of the B ring into the wider rim of the Cd cavity

Liposomes as carriers for verbascoside: stability and skin permeation studies

In this study the influence of liposomal incorporation on both the stability and the in vitro (trans) dermal delivery of verbascoside was evaluated. The effect of drug entrapment into vesicles on its radical scavenging activity was also studied. Liposomes were obtained from soy phosphatidylcholine and cholesterol according to the film hydration method. Stability of verbascoside-loaded vesicles was studied over 6 months. Results showed that verbascoside can be incorporated in liposomes (E% = 57-66%), preventing its degradation. Stability studies (dynamic lager light scattering [DLLS] measurements and transmission electron microscopy [TEM] visualization) pointed out that vesicles were stable for 90 days and neither verbascoside leakage nor vesicle size alteration occurred during this period. The effects of vesicular incorporation on verbascoside diffusion through skin were investigated in vitro using newborn pig skin. Results showed that liposomes promoted drug accumulation into the stratum corneum but they did not give rise to any significant transdermal verbascoside delivery. Finally, results obtained from a 1, 1-diphenyl-2-pierylhydrazyl (DPPH) radical assay demonstrated that liposomes did not interfere with the radical scavenging activity of verbascoside

Variation in artemisinin and flavonoid content in different extracts of Artemisia annua L.

Artemisia annua L. is a promising and potent antimalarial drug. This activity has been ascribed to its content of artemisinin, a sesquiterpene lactone that is stage specific and very effective against drug-resistant Plasmodium species and which has low toxicity. The in vitro antiplasmodial activity of artemisinin is enhanced by the flavonoids of the extract, as recently proposed by the authors. Different extracts (tinctures, infusions and decoctions), obtained from a cultivar selected by the University of Campinas (0.52% artemisinin), were analyzed in order to prove the selectivity of the solvents to obtain high yields of both artemisinin and flavonoids. Tinctures 40 and 60% v/v showed a greater power of extraction in comparison with infusions and decoctions. The best performance was obtained using 60% v/v tincture. The extraction efficiency for artemisinin was 40% and for flavonoids was 29.5%. Among aqueous extracts, the best results were obtained by preparing an infusion with boiling water, left to cool for 15 minutes before filtration. The extraction efficiency for artemisinin was 57.5% and for flavonoids was 8.2%. If leaves are boiled for several minutes the artemisinin concentration is decreased, probably due to the heat instability of this constituent. Also microwave could represent a valid alternative method to extract the phytocomplex, the extraction efficiency for artemisinin was 4 1.0% and that for flavonoids was 7.7%.1121111111