Evolution of minor polar compounds and antioxidant capacity during storage of bottled extra virgin olive oil

We characterized "Olivastra Seggianese" extra virgin olive oil (EVOO) and evaluated its chemical and sensory characteristics and antioxidant and antiradical activities during storage under novel conditions. Two oils (A and B) were analyzed for the commodity characteristics at blending (t0) and after 9, 12, and 18 months; panel tests were performed and minor polar compounds (MPC) content was assessed at blending (t0) and after 6, 9, 12, and 18 months. Antioxidant and antiradical activities in vitro were evaluated at t0 and after 12 months, by human low density lipoprotein (LDL) and 1,1-diphenyl-2-picrylhydrazil radical (DPPH*) tests. Oil A, which had an initially higher MPC content, possessed "harder" organoleptic characteristics than oil B, which had a lower MPC content and was endowed with a "smoother" taste profile. Statistical analyses showed that secoiridoids, particularly deacetoxy-oleuropein aglycone, should be quantified to evaluate EVOO stability during storage. The antioxidant activity toward human LDL was linked to MPC content and to storage time. The tests on the stable free radical DPPH* confirmed the results on human LDL. We propose this as an additional parameter to evaluate olive oil quality and stability over time.

Antioxidant effect of two virgin olive oils depends on the concentration and composition of minor polar compounds

In vitro studies show that some individual minor polar phenolic compounds (MPC) present in virgin olive oil prevent oxidation of human low-density lipoproteins (LDL), but few data are available on the antioxidant effect of whole oil extract. Thus, whole virgin olive extracts were studied to determine whether they maintain the antioxidant activity and whether this last is linked to MPC composition of a single virgin oil. Using HPLC-DAD the MPC content in Taggiasca and Seggianese virgin olive oils was measured. Taggiasca oil was less rich in total MPC (208.5 mg/L) than Seggianese oil (441.9 mg/L). In addition, the major compounds of Taggiasca oil were lignan derivatives, whereas the major compounds in Seggianese oils were secoiridoid derivatives. Moreover, Taggiasca oil was practically free of 5-hydroxytyrosol and 5-hydroxytyrosol derivatives, deacetoxy-oleuropein aglycone and oleuropein aglycone. The antioxidant activity of the oils on human LDL was evaluated by measuring malondialdehyde and conjugate diene generation induced by copper ions. In both tests, the oil extracts dose-dependently reduced malondialdehyde and conjugate diene generation. Moreover, antioxidant potency correlated with total MPC; thus, Seggianese extract was more active. The two oils differed quantitatively and qualitatively, and these differences influenced their biological activities; thus clinical trials focused on studying the effects of olive oils should specify the oils used.

Triterpenoids and ellagic acid derivatives from in vitro cultures of Camptotheca acuminata Decaisne

The metabolic profile of secondary products in calli and cell suspension cultures of Camptotheca acuminata Decaisne was investigated and compared to that of the leaves and roots taken from the plant. Neither in vitro system produced the anticancer quinoline alkaloid camptothecin (CPT); they accumulated discrete quantities of polyhydroxylated triterpenoids, different from those found in the plant organs, and ellagic acid derivatives. Nine ellagic acid derivatives (1a-1d and 2a-2e) and eight triterpenoid acids (3a-3e and 4a-4c) were isolated and characterised. All the identified triterpenes were related to ursane- or oleanane-type skeletons and their concentrations rose to 4.5% in suspended cells.

Analysis of condensed and hydrolysable tannins from commercial plant extracts

High performance liquid chromatography (HPLC)/DAD and MS qualitative and quantitative analyses of polyphenols, hydrolysable and condensed tannins from Pinus maritima L. and tannic acid (TA) extracts were performed using normal and reverse phase. Normal-phase HPLC was more suitable for pine bark (PBE) and tannic acid extracts analysis. The chromatographic profile revealed that P. maritima L. extract was mainly composed by polymeric flavanols (containing from two to seven units) and tannic acid (characterized by a mixture of glucose gallates containing from three to seven units of gallic acid). Concerning their antimycotic properties, P. maritima L. extract exhibited a broad activity towards yeast strains of the genera Candida, Cryptococcus, Filobasidiella, Issatchenkia, Saccharomyces: MICs from 200 to 4000 microg/ml (corresponding to 140-2800 microg/ml of active polyphenols) were determined. Conversely, no activity of tannic acid was observed over the same target microorganisms. Taken into consideration the above results of HPLC analysis and on the basis of the current literature, we may conclude that only 70.2% of polyphenols (recognized as condensed tannins) occurring in P. maritima L. extract can be apparently considered responsible for its antimycotic activity.

Electrospray ionisation tandem mass spectrometric investigation of phenylpropanoids and secoiridoids from solid olive residue

This work is focused on the recovery and structural characterisation of bioactive compounds from SOR (solid olive residue), a low cost and widely available by-product in the Mediterranean basin. In the light of the interesting biological activities attributed both to secoiridoid and phenylpropanoids, the aim of this work was to carry out a systematic tandem mass spectrometric study for the identification and characterisation of these two class of compounds extracted from SOR derived from Coratina, a cultivar widely diffused in the south of Italy. Five phenylpropanoids, in addition to verbascoside, and two new secoiridoids were identified.

Solid olive residues: insight into their phenolic composition

Solid olive residues (SOR) are byproducts of the olive-milling process, but they have an increasing importance in the pharmaceutical industry due to their rich content of biophenols. Such compounds are studied widely for their antioxidant and antimicrobial activities, but there is a lack of information about their quantitative recovery. This research highlighted the key role played both by the selection of the cultivar and by the degree of olive fruit ripening on the phenolic content on the SOR. The extraction methods were selected to reach the best quantitative results mainly using a safe food solvent. In light of the results the Soxhlet extraction with ethanol could be proposed as preferential for a higher recovery of verbascoside and its analogues.

Evaluation of the phenolic content in the aerial parts of different varieties of Cichorium intybus L

Fresh aerial parts of different chicory varieties: green chicory (c.v. "Catalogna"), two red chicory varieties ("radicchio rosso di Chioggia" and "radicchio rosso di Treviso"), and Witloof or Belgian endive were analyzed by HPLC/DAD/MS. The chromatographic fingerprint was diagnostic for each variety. A monocaffeoyl tartaric acid, chlorogenic acid, and chicoric acid were detected in all the varieties, while cyanidin 3-O-glucoside, delphinidin 3-O-(6'' malonyl) glucoside, and cyanidin 3-O-(6'' malonyl) glucoside were the main phenolic compounds in the red varieties. The flavonoidic compounds, quercetin 3-O-glucuronide and luteolin 7-O-glucuronide, were absent in the Witloof sample. The phenolic compounds from total leaves were the same as those obtained from only the colored parts; nevertheless, the total amount was remarkably lower with a decrease of up to 80% for Belgian endive. Chemical stability at high temperature was observed for the phenolic fraction from the green variety after decoction at 100 degrees C for 30 min.

The effect of growth regulators and sucrose on anthocyanin production in Camptotheca acuminata cell cultures

The effect of different concentrations of growth regulators and sucrose on anthocyanin production in cell suspension cultures of Camptotheca acuminata Decaisne (Nyssaceae) was described for the first time and qualitatively and quantitatively evaluated. Anthocyanin production was significantly greater in the presence of kinetin, compared to benzyladenine, with the greatest concentration observed in the presence of 2 microM kinetin. No significant differences in anthocyanin production were observed when comparing 2,4-dichlorophenoxyacetic acid to alpha-naphthaleneacetic acid, except when using 2 microM, 2,4-dichlorophenoxyacetic acid, which resulted in greater anthocyanin production. High sucrose concentration enhanced the production of anthocyanins. Based on the absence of anthocyanin production in the dark, we concluded that light was essential for stimulating anthocyanin production. The optimised medium consisted of: 2 microM kinetin, 2 microM 2,4-dichlorophenoxyacetic acid and 292 mM sucrose. HPLC/DAD and HPLC/MS analyses revealed that the main anthocyanin was Cy 3-O-galactoside and that the minor derivative was Cy 3-O-glucoside.

Germplasm characterization of Zolfino landraces (Phaseolus vulgaris L.) by flavonoid content

The flavonoid composition of three phenotypes of "Zolfino" landraces, a typical bean grown in Tuscany, has been elucidated by means of HPLC-DAD and HPLC-MS analysis. Flavonols, isoflavones, and anthocyanins have been separated and determined in the different samples chosen on the basis of their seed coat color. A flavonol that has not been previously found in Phaseolus vulgaris L. seeds has been characterized. The quantitative data show the presence of flavonols (ranging from 709 to 118 mg/kg of fresh weight), isoflavones (ranging from 14 to 2 mg/kg of fresh weight), and anthocyanins, in black beans only. These results show that this genotype could be very interesting from a nutritional point of view.

Commercial and laboratory extracts from artichoke leaves: estimation of caffeoyl esters and flavonoidic compounds content

Artichoke leaf extracts are widely used alone or in association with other herbs for embittering alcoholic and soft drinks and to prepare herbal teas or herbal medicinal products. Despite this wide diffusion, the European Pharmacopoeia does not report an official method for the determination of the active principles of artichoke leaf extracts. This work reports a quali-quantitative determination by HPLC/DAD and HPLC/MS techniques of both cynnamic acids and flavonoids present in some artichoke leaf commercial extracts (Com) compared with two different laboratory extracts (Lab). Most of the commercial extracts showed a similar quali-quantitative pattern with a single exception having five-six times higher value. The quantitative data from the Italian Pharmacopoeia(IP) official method does not evaluate the flavonoidic fraction and showed an overestimation of the caffeoyl esters with respect to the HPLC/DAD results. The proposed HPLC/DAD method was able to completely characterize and quantify this matrix and represents a contribution to better quality control of these herbal extracts.

Identification and quantification of galloyl derivatives, flavonoid glycosides and anthocyanins in leaves of Pistacia lentiscus L

Separation, identification and quantification of polyphenols was carried out on leaves of Pistacia lentiscus L., 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. lentiscus tissue extracts in human health care.

Polyphenolic content in olive oil waste waters and related olive samples

The production of olive oil yields a considerable amount of waste water, which is a powerful pollutant and is currently discarded. Polyphenols and other natural antioxidants, extracted from olives during oil extraction process, partially end up in the waste waters. Experimental and commercial olive oil waste waters from four Mediterranean countries were analyzed for a possible recovering of these biologically interesting constituents. Identification and quantitation of the main polyphenols were carried out by applying HPLC-DAD and HPLC-MS methods. Representative samples of ripe olives were also analyzed at the same time to correlate, if possible, their polyphenolic profiles with those of the corresponding olive oil waste waters. The results demonstrate that Italian commercial olive oil waste waters were the richest in total polyphenolic compounds with amounts between 150 and 400 mg/100 mL of waste waters. These raw, as yet unused, matrices could represent an interesting and alternative source of biologically active polyphenols.

Identification of volatile constituents of Tambourissa leptophylla

The volatile fraction of Tambourissa leptophylla fruit skin was extracted by petrol ether, purified by adsorption chromatography (LPC) and analysed by gas chromatographic-spectroscopic methods. 27 non-oxygenated terpene hydrocarbons and 10 oxygenated derivatives were identified. The most abundant components were: limonene (24.0%), cis-alpha-bergamotene (23.2%), delta-3-carene (8.2%), alpha-curcumene (6.0%), trans-alpha-bergamotene (5.1%), alpha-copaene (4.1%), alpha-pinene (4.0%), p-cymene (4.0%) and bicyclogermacrene (3.3%). The crude volatile fraction was tested in vitro against Cladosporium cucumerinum in direct bioautography on TLC plates on the basis of the antifungal use of fruit skin. Activity of petrol ether extract against this micro-organism was demonstrated.

Stabilisation of natural anthocyanins by micellar systems

In this paper, we discuss the influence of different micellar systems on the degradation of natural anthocyans, either glycosides and aglycones, at pH values ranging from 2.8 to 6.0. The interaction of anthocyanins, in suitable dispersed systems such as negative micelles of sodium dodecylsulphate (SDS), consistently increased their chemical stability in aqueous solutions. The results of these experiments point out how both the number of available negative charges and the presence of an organised distribution of the negative charges on the micellar surface appear to be necessary conditions to achieve the anthocyanins' stability and colour retention. The sodium dodecylbenzensulphonate (SDBS), containing an aromatic ring near the negative surface of the micelle, seems to increase the rate of decomposition. Preliminary findings of circular dicroism (CD) investigation allowed us to hypothesise that these pigments undergo an intermolecular self-association process induced by the SDS micelles and this phenomenon presumably contribute to increase stability.

Hydroxytyrosol, as a component of olive mill waste water, is dose- dependently absorbed and increases the antioxidant capacity of rat plasma

Hydroxytyrosol is the most potent phenolic antioxidant of olive oil and olive mill waste water (OMWW) and its biological activities have stimulated research on its potential role in cardiovascular protection. However, evidence of the absorption of OMWW phenolics and on their possible in vivo activity has, until now, never been provided. Three groups male Sprague-Dawley rats were administered 1, 5, or 10 mg/Kg of the OMWW extract, respectively, providing 41.4, 207, and 414 microg/Kg of hydroxytyrosol, respectively. Urine was collected for 24 h and the urinary levels of hydroxytyrosol were quantified by mass spectrometry. Hydroxytyrosol was dose-dependently (R(2) = 0.95) absorbed and excreted in the urines mostly as a glucuronide conjugate. Further, the administration of an hydroxytyrosol-rich OMWW extract (10 mg/kg) to the rats was also associated with an increase of their plasma antioxidant capacity. Future experiments will eventually further clarify its metabolic fate and its in vivo actions.

Flavonoids accumulate in leaves and glandular trichomes of Phillyrea latifolia exposed to excess solar radiation

Experiments were conducted on Phillyrea latifolia plants grown under a dense overstorey of Pinus pinea (shade plants) or on seashore dunes (sun plants) in a coastal area of Tuscany (42° 46' N, 10° 53' E). Total integrated photon flux densities averaged 1.67 and 61.4 m mol m^-2 d^-1 for shade and sun sites, respectively. A leaf morphological-structural analysis, a qualitative and quantitative analysis of phenylpropanoids of leaf tissue and leaf surface, and a histochemical localization of flavonoids were conducted. The area of sun leaves reached 57% of that of shade leaves, whereas leaf angle (β), sclerophylly index (ratio of leaf d. wt:leaf area), and trichome frequency (trichome number mm^-2 ) were markedly greater in leaves exposed to full solar radiation than in leaves acclimated to shade. The total thickness of sun leaves was 78% higher than that of shade leaves, mostly owing to a greater development of both palisade parenchyma and spongy mesophyll. The concentration, but not the composition, of leaf tissue phenylpropanoids varied significantly between sun and shade leaves, with a marked increase in flavonoid glycosides in sun leaves. Flavonoids occurred almost exclusively in the upper epidermal cells of shade leaves. By contrast, flavonoids largely accumulated in the upper and lower epidermis, as well as in the mesophyll tissue of leaves that were acclimated to full sunlight. Flavonoid glycosides were found exclusively in the secretory products of glandular trichomes of P. latifolia leaves exposed to high levels of light; luteolin 7-O- glucoside and quercetin 3-O-rutinoside were the major constituents. By contrast, verbascoside and an unidentified caffeic acid derivative constituted 72% of total phenylpropanoids secreted by glandular trichomes of shade leaves, whereas they were not detected in glandular trichomes of sun leaves. These findings suggest that the light-induced synthesis of flavonoids in glandular trichomes of P. latifolia probably occurs in situ and concomitantly inactivates other branch pathways of the general phenylpropanoid metabolism. This is the first report of the key role of glandular trichomes and of flavonoid glycosides in the integrated mechanisms of acclimation of P. latifolia to excess light.

In-vitro antioxidant and in-vivo photoprotective effect of three lyophilized extracts of Sedum telephium L. leaves

Sedum telephium L. is a medicinal plant used in antiquity to cure many types of inflammatory skin diseases. The leaves (without the external cuticle), are used to promote healing and reduce skin inflammation and pain, and contain various components. We found two major components: flavonol glycosides and polysaccharides, with molecular weight between 13,000 and 13,500 Da. We evaluated the in-vitro antioxidant and in-vivo skin photoprotective effects of three lyophilized extracts obtained from the juice of S. telephium L. leaves: a total lyophilized juice, a lyophilized flavonolic fraction, and a lyophilized polysaccharidic fraction. Two in-vitro models were used: the bleaching of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical, and the protective effect against UV-induced peroxidation on phosphatidylcholine multilamellar vesicles, as model membranes. The antioxidant/radical scavenging activity of each lyophilized extract was also assessed in-vivo by determining their ability to reduce UVB-induced skin erythema (monitored by reflectance spectrophotometry) in healthy human volunteers. The findings of the in-vitro experiments clearly demonstrated that, unlike the lyophilized polysaccharidic fraction, the lyophilized flavonolic fraction and total lyophilized juice possess strong antioxidant/free radical scavenging properties, which are likely due to phenolic compounds. Consistent with these findings, gel formulations of both the total lyophilized juice and, to a greater degree, the lyophilized flavonolic fraction appeared to possess a strong protective effect against UV-induced skin erythema in-vivo, whereas the lyophilized polysaccharidic fraction was completely ineffective. The in-vitro and in-vivo results suggest that, both the total lyophilized juice and, in particular, the lyophilized flavonolic fraction, but not the lyophilized polysaccharidic fraction of S. telephium L. leaves, have photoprotective effects against UVB-induced skin damage.

HPLC analysis of flavonoids and secoiridoids in leaves of Ligustrum vulgare L. (Oleaceae)

Identification and quantification of flavonol glycosides and secoiridoids was carried out on leaves of Ligustrum vulgare L. (Oleaceae) by means of HPLC-DAD and HPLC-MS analysis. In addition to previously reported secoiridoids (oleuropein, ligustaloside A, ligustaloside B, and ligstroside) four kaempferol glycosides (kaempferol 3-O-glucoside 7-O-rhamnoside, kaempferol 3, 7-O-dirhamnoside, kaempferol 3-O-rhamnoside, and kaempferol 3-O-glucoside) and two quercetin glycosides (quercetin 3-O-glucoside 7-O-rhamnoside and quercetin 3,7-O-dirhamnoside) were present in leaves of L. vulgare L. Although secoiridoids accounted for nearly the 76% of the total leaf polyphenols content (with ligustaloside A as the main component), kaempferol glycosides were also accumulated in the leaves of L. vulgare L. to a relatively high extent (23%). Contribution of quercetin derivatives was minor under our experimental conditions. Our findings suggest that flavonol glycosides may have a central role in both the ecology and the biology of L. vulgare L.

Sedum telephium L. polysaccharide content affects MRC5 cell adhesion to laminin and fibronectin

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.

Comparison among differential pulse voltammetry, amperometric biosensor, and HPLC/DAD analysis for polyphenol determination

Polyphenols are widespread in vegetables and fruits. They can play an important role in human diet and health, and they influence the sensorial properties of many foods, and act as natural antioxidants. This study was conducted using HPLC/DAD, tyrosinase biosensor, and differential pulse voltammetry (DPV) analyses to detect polyphenolic compounds in natural complex matrices. The analyses were applied to a series of both standards and natural extracts derived from grape, olives, and green tea. The pure compounds include phenolic acids, flavones, flavonols, catechins, tannins, and oleuropein. HPLC/DAD, DPV, and the biosensor approach were used as independent analytical techniques. Bare graphite screen-printed electrodes were employed in DPV and in the biosensor analysis. The most accurate data were obtained by HPLC/DAD analysis, while the DPV approach using screen-printed electrodes could represent a quick screening method for the determination of polyphenols in natural extracts. Use of the biosensor for the analysis of complex matrices needs further study in order to improve its performance.

Antioxidant and other biological activities of olive mill waste waters

During olive oil production, large volumes of water are generated and subsequently discarded. Olives contain a variety of bioactive components, and some of them, according to their partition coefficients, end up in the water phase. The current investigation aimed at comparing different methods for the extraction of biologically active components of the olive mill waste waters (OMWW) and evaluating the in vitro antioxidant and anti-inflammatory activities of the resulting extracts. The results indicate that OMWW extracts are able to inhibit human LDL oxidation (a process involved in the pathogenesis of atherosclerosis) and to scavenge superoxide anions and hypochlorous acid at concentrations as low as 20 ppm. Finally, two of the three extracts also inhibited the production of leukotrienes by human neutrophils. The potency of the extracts depended on their degree of refinement: extracts containing only low molecular weight phenols were the most effective.

Polyphenolic content in five tuscany cultivars of Olea europaea L

In this study polyphenolic compounds extracted from olive fruits of five registered cultivars were analyzed. A solid-liquid extraction (LSE) procedure with Extrelut cartridge (diatomaceous earth) using different eluents was developed to obtain polyphenolic compounds. HPLC-DAD and HPLC-MS methods were applied for the quali-quantitative analysis of each fraction obtained from LSE. The results of this work show that the LSE procedure with diatomaceous earth cartridge supplies a rapid and reproducible fractioning method able to obtain a quantitative recovery of all compounds and to collect fractions directly analyzed by HPLC. A comparison among different cultivars shows significant quantitative differences in some polyphenols, such as verbascoside, anthocyanic compounds, and oleuropein derivatives.

HPTLC and reflectance mode densitometry of anthocyanins in Malva silvestris L.: a comparison with gradient-elution reversed-phase HPLC

Aqueous alcoholic mallow flower extracts were analyzed both by HPTLC-densitometry in the reflectance mode at 530 nm and by reversed-phase HPLC with gradient elution. For the mallow flower anthocyanins the best chromatographic resolution was obtained by HPLC, which revealed only two main compounds, confirmed by FAB-MS: malvidin 3,5-O-diglucoside (malvin) and malvidin 3-O-(6"-O-malonylglucoside)-5-O-glucoside. The HPTLC densitometric method on cellulose plates provides accuracy, reproducibility and selectivity for the quantitative analysis of the anthocyanins and this method was shown to be much more sensitive than the HPLC-DAD system, at 530 nm. Both methods give comparable quantitative results for total anthocyanins when applied to mallow flowers from two different sources: Italy and Albania.

Improvement of dissolution characteristics of psoralen by cyclodextrins complexation

Psoralen was found to form an inclusion complex with beta-cyclodextrin (beta CD), heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM beta CD) and hepatakis(2,3,6-tri-O-methyl)-beta-cyclodextrin (TM beta CD). Phase solubility studies revealed the formation of a 1:1 molar complexes. The stability constant were 663 M-1 for beta CD, 603 M-1 for DM beta CD and 69.6 M-1 for TM beta CD. The formation of complexes in the solid state was confirmed by spectroscopic analyses, X-ray diffractometry and differential thermal data. The solubility and dissolution rate of the complexed forms were improved, particularly for the DM beta CD complex. The strength of binding of psoralen to DNA was not influenced by complexation with cyclodextrins.

Anti-inflammatory and immunologically active polysaccharides of Sedum telephium

Two major polysaccharides, rhamnogalacturonans with mean M(r)s of 13,500 and 13,000, were isolated from dried leaves of Sedum telephium by column chromatography on DEAE-Sepharose CL-6B and gel filtration on Fractogel TSK HW-50 (S) and Sephacryl 200 HR. The structures were determined mainly by NMR spectroscopy, methylation analysis and GC-MS of the partially methylated alditol acetates, carboxyl reduction and by analysis of acidic and enzymatic degradation products. Both polysaccharides exert an anticomplementary effect in vitro, induce TNF-alpha-production, enhance phagocytosis in vitro and in vivo, and exhibit anti-inflammatory activity.

Flavone photoreactivity. UV-induced reactions in organic solvents and micellar systems

Flavonoid photochemistry is a subject of interest in studies dealing with the role of phenolic compounds as screening pigments in plants. In order to contribute to the understanding of the processes involved in the interaction between flavonoids and UV radiation, we have studied UV-induced flavone photodegradation in both organic solvents and micellar systems. The results obtained show that flavone photosensitivity depends on the characteristics of the reaction environment and is influenced by the medium polarity and the charges on the micellar surface. Qualitative and quantitative differences in the photodegradation products were demonstrated by high performance liquid chromatography (HPLC) analysis.

An approach to the study of the biological activity of Eschscholtzia californica Cham

Pharmacological activities of Eschscholtzia californica Cham. are not yet well known. The aim of this work is to verify the pharmacological properties and to get a first identification of the active principles.