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Summary • The differential accumulation of various polyphenols, particularly of flavonoids and hydroxycinnamates, was studied in leaves of Ligustrum vulgare exposed to increasing sunlight under well watered or drought-stress conditions. • Light- and drought-induced changes in leaf polyphenol concentrations were normalized to the CO2 assimilation rate. The functional roles of flavonoids and hydroxycinnamates were analysed through tissue localization using multispectral fluorescence microimaging, and through efficiencies to scavenge superoxide radicals (O2−) and to screen UV wavelengths. • Clear effects of light and water treatments on leaf polyphenol concentrations were not observed, as the CO2 assimilation rate varied according to sunlight and water availability. However, biosynthesis of quercetin 3-O-rutinoside, luteolin 7-O-glucoside and echinacoside, which were efficient O2− scavengers, increased sharply in response to solar radiation. By contrast, carbon for the synthesis of p-coumaric acid and monohydroxyflavones, efficient UV screeners but poor O2− scavengers, did not vary depending on light treatments. Flavonoids accumulated in both the adaxial epidermis and the palisade tissue because of sunlight irradiance, whereas echinacoside occurred largely in abaxial tissues. • We hypothesize that flavonoids may serve antioxidant functions in response to excess light and drought stress, and that a coordinate control system between hydroxycinnamate and flavonoid pathways operated in L. vulgare exposed to excess light.

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.

Fluorescence sensors are useful tools for the non-destructive assessment of grape berry anthocyanins. The Multiplex (Mx) sensor here studied provides two anthocyanin indices: ANTHR = log(1/Chl-fluorescence_R) and ANTHRG = log(Chl-fluorescence_R/Chl-fluorescence_G), based on the chlorophyll (Chl) fluorescence excited with red (R) and green (G) light. These indices were calibrated against wet chemistry. The dependence of anthocyanin prediction models on cultivar, season and site was studied on four cultivars in two Italian regions during three consecutive years. The 2010 global model (all cultivars at both growing sites) gave relative prediction errors on anthocyanin content less than 14.1% (ANTHR) and 19.0% (ANTHRG). The ANTHRG was independent of season, maintaining a relative error of about 20% in both 2011 and 2012. In field applications of the calibrated Mx, it showed its ability to detect inter-plot and inter-season differences on both growing sites.

A hydroxytyrosol (HTyr)-enriched fraction containing HTyr 6% w/w, derived from Olea europaea L. byproducts and obtained using an environmentally and economically sustainable technology, was lipophilized under green chemistry conditions. The effects of three fractions containing hydroxytyrosyl butanoate, octanoate, and oleate, named, respectively, lipophilic fractions 5, 6, and 7, and unreacted HTyr on the human colon cancer cell line HCT8-β8 engineered to overexpress estrogen receptor β (ERβ) were evaluated and compared to those of pure HTyr. The experimental data demonstrated that HTyr and all fractions showed an antiproliferative effect, as had been observed by the evaluation of the cellular doubling time under these different conditions (mean control, 32 ± 4 h; HTyr 1, 65 ± 9 h; fraction 5, 64 ± 11 h; fraction 6, 62 ± 14 h; fraction 7, 133 ± 30 h). As evidenced, fraction 7 containing hydroxytyrosyl oleate showed the highest activity. These results were related to the link with ER-β, which was assessed through simultaneous treatment with an inhibitor of ERβ.

The sustainability of the water sector is a major concern. Compliance with current legislation alone does not seem to be enough to face major challenges such as climate change or population growth and concentration. The greatest potential for improvement appears to be when companies decide to step forward and go beyond environmental legislation. This chapter focuses on the environmental responsibility of small and medium-sized enterprises in the water and waste management sector, analyzing the drivers that lead these firms to adopt more sustainable and innovative practices. Market pull has a low incidence in encouraging environmental responsibility, whereas values and the strategic decisions of entrepreneurs seem to be decisive. Policy makers should prioritize subsidies over fiscal incentives because they show greater potential to promote the adoption of environmental responsibility among these firms.

The introgressed cultivar of Parainema coffee was studied in two Honduras plantations that differed in their tree-shading system, namely intercropping as opposed to agroforestry. The cumulative sunlight effect on plants was determined by means of a non-destructive index of leaf flavonols, applied here for the first time to the coffee culture. The coffee seeds selectively harvested from shaded and full sunlight plants were analyzed for both their chemical composition and the derived cup quality. The high and constant shading of the agroforestry system determined both the heaviest coffee beans and an excellent rating of the beverage. Green beans under shade contained higher levels of caffeine and lower levels of trigonelline and mono-caffeoylquinic acids (other than chlorogenic acid) than those from sun-exposed plants. Banana-tree shading produced no differences in the green bean chemicals with respect to sunlight. The employed leaf flavonol optical index allowed to quantify the spatial variability of shading within the coffee plantations. Regardless of the light regime and site, Parainema coffee was classified as a “specialty”, an aspect that, together with its high seed weight and resistance to disease, can further favor its spread among coffee producers.

Introduction Kiwifruit contains high amounts of anti-oxidants beneficial to health. Its quality is influenced by ripening time, genotype, cultivation techniques, climate and storage conditions after harvest. Objective The aim of the present study was to characterise the phenolic content by HPLC methods and to evaluate the performance of a portable optical sensor (Multiplex 3), for in vivo non-destructive phenolic compound assessment in kiwifruits. Methods Kiwifruits peel extracts were characterised by reverse-phase (RP) HPLC with diode-array detector (DAD) and electrospray ionisation (ESI) with MS using the Zorbax SB-Aq. column from Agilent. The fluorimetric sensor method is based on the screening of fruit chlorophyll fluorescence excitation and allows the UV absorbance of intact fruit skin to be measured. The flavonol index, FLAV, was calculated as log(FRFR/FRFUV), where FRFR and FRFUV are the chlorophyll fluorescence excited with red and UV light. Results Hydroxycinnamic acids, procyanidins, and quercetin glycosides were the main polyphenol classes detected by HPLC–DAD–ESI/MS in the kiwifruit skin. A good linear regression (R2 = 0.88) was found between the fluorimetric sensor FLAV index and flavonol chromatographic analysis of the fruits. The FLAV index was able to detect the higher content of flavonols in sun-exposed fruits with respect to mid-shaded and shaded ones in accordance with the destructive analysis. Conclusion The fluorimetric sensor represents a rapid and non-invasive tool to: (i) monitor the flavonol accumulation in kiwifruit and to assess its quality concerning the healthy anti-oxidant properties; (ii) evaluate the effect of environmental and agronomical factors related to the fruit quality; and (iii) select fruits with the largest flavonol content, and consequently less susceptible to pathogen attack, in order to improve their storage durability. Copyright © 2013 John Wiley & Sons, Ltd.

A sustainable extractive technology followed by membrane separation methods was applied to Olea europaea L. (leaves and pitted olive pulp) and Cynara scolymus L. by-products (leaves and stems), to obtain different standardized commercial extracts for application in the functional food industry, pharmaceutical and cosmetic fields. The entire treatment, PCT registered, consists of water extraction of the aforementioned vegetal material and the following steps of fractionation: (1) microfiltration (only for Olea); (2) ultrafiltration (only for Cynara); (3) nanofiltration (only for Olea); (4) reverse osmosis and final concentration by evaporation at low temperature or spray-dried technique. Thanks to these steps, different fractions enriched with phenolic compounds that have an economic value can be obtained. These fractions were characterized and quantified by HPLC/DAD-ESI/MS and then tested for their antiradical and antioxidant properties. The EC50 values by DPPH test were 6.76 × 10−3 mM for the Olea green leaves (GL) soft extract, 5.44 × 10−3 mM for the Olea dried leaves (DL) soft extract, and 1.22 × 10−3 mM in the case of the Olea OH-Tyr soft extract. The EC50 value of the Cynara GL soft extract was 3.25 × 10−3 mM. The ORAC results were 3632 ± 110.7 µmoL TE/g for OH-Tyr Olea soft extract, 1410 ± 62.1 µmoL TE/g for GL Olea soft extract, and finally 760 ± 12 µmoL TE/g for GL Cynara soft extract, confirming the highest antioxidant activity of hydroxytyrosol.

This paper describes a circular economy process based on environmentally and economically sustainable procedures which was applied to the sector of olive oil processing on an industrial scale. Olea europaea L. tissues and by-products represent a renewable and low-cost source of polyphenols, in particular hydroxytyrosol (HTyr), a naturally occurring compound well known for its biological properties. Specifically, green leaves (GL), dried leaves (DL), and pitted olive pulp were treated with water in a pneumatic extractor to obtain the corresponding polyphenolic extracts. Three standardized fractions, named Soft Extract Olea GL, Soft Extract Olea DL, and Soft Extract Olea HTyr resulted after the following two steps: a separation process carried out by membrane technology, and a concentration step performed under reduced pressure and low temperature. The polyphenolic fractions showed antiradical activity and have potential industrial applications in the food, nutraceutical, pharmaceutical, feed, and agronomic fields. Novel functionalized extracts containing hydroxytyrosol methyl carbonate (HTyr-MC) were obtained from Soft Extract Olea HTyr through an innovative approach based on green chemistry procedures, which appear to be a promising tool to increase the applications of the polyphenolic extracts.

Sweet Chestnut ( Castanea sativa Mill.) wood extracts, rich in Hydrolyzable Tannins (HTs), are traditionally used in the tanning and textile industries, but recent studies suggest additional uses. The aim of this work is the HPLC-DAD-ESI-MS characterization of Sweet Chestnut aqueous extracts and fractions obtained through a membrane separation technology system without using other solvents, and the evaluation of their antioxidant and antiradical activities. Total tannins range between 2.7 and 138.4 mM; gallic acid ranges between 6% and 100%; castalagin and vescalagin range between 0% and 40%. Gallic Acid Equivalents, measured with the Folin-Ciocalteu test, range between 0.067 and 56.99g/100g extract weight; ORAC test results for the marketed fractions are 450.4 and 3050 μmol/g Trolox Equivalents/extract weight. EC50 values, measured with the DPPH test, range between 0.444 and 2.399 μM. These results suggest a new ecofriendly and economically sustainable method for obtaining chestnut fractions with differentiated, stable and reproducible chemical compositions. Such fractions can be marketed for innovative uses in several sectors.

In the present work, several tannin extracts from myrtle and pomegranate were analyzed and characterized using HPLC/DAD/ESI-MS methods. Both aqueous and hydroalcoholic myrtle leaf extracts were found to be rich in galloyl-glucosides, galloyl-quinic acids, ellagitannins and flavonoids. In these extracts we observed a predominance of galloyl-glucosides and galloyl-quinic derivatives with respect to ellagic derivatives; 87.14% and 12.86%, respectively, average gallic and ellagic derivatives with respect to total tannins content. In pomegranate extracts, substantial differences were found in polyphenol contents between peel and seed extracts with regard to the relative abundance of gallic and ellagic acid derivatives: 28.81% and 71.19%, respectively, as average total gallic and ellagic derivatives in peel extracts; 61.30% and 38.70%, in seed extracts. The antiradical properties were evaluated and compared to those of two commercial extracts of chestnut bark and grape seeds. The collected data could suggest the use of myrtle and pomegranate extracts as nutraceuticals and functional foods for their important antioxidant properties.

Chlorophyll fluorescence excitation techniques have been used in plant science for more than one decade to non-destructively estimate phenolic compounds in the epidermal cell layer. These techniques have been used here to evaluate the effect of different light intensities and spectral quality on the accumulation of ortho-dihydroxylated flavonoids in Phyllirea latifolia L., Myrtus communis L. and Ligustrum vulgare L. In a first experiment, chlorophyll fluorescence excitation spectra were measured (with a double arm optical fiber bundle connected to a spectrofluorimeter) on the adaxial and abaxial leaf surfaces of container-grown P. latifolia and M. communis exposed to 20% or 100% full sunlight. Differences in epidermal absorption spectra (referred to as epidermal absorption spectra throughout the paper) were then calculated from the relative chlorophyll fluorescence excitation spectra. This allowed comparing the content of UV-absorbing compounds between differentially irradiated leaves as well as between adaxial and abaxial epidermal layers. The absorption spectra were characterized by a band centered at 360–380 nm, which was greater in sun than in shade leaves and in the adaxial than in the abaxial surfaces, irrespective of species. Based upon HPLC-DAD and HPLC–MS analyses of leaf extracts and UV-spectral features of individual flavonoids, we conclude that quercetin, luteolin and myricetin derivatives were responsible for the observed light-induced changes in the spectral features of examined tissues. In a second experiment, we grew L. vulgare potted plants at 30% or 85% full sunlight in the presence or in the absence of UV radiation. We measured the absorbance characteristics at 370 nm of three leaf-pairs located in the apical portion of each shoot, using a portable fluorimetric sensor, the Multiplex ® . This allowed estimating, non-destructively, an index closely related to the concentration of epidermal flavonols and flavones having an ortho-dihydroxyl substitution in the B-ring. This index was greater in leaves growing at 85% than at 30% sunlight, irrespective of UV irradiance. When plants acclimated for 3 weeks to 30% sunlight, in the presence or in the absence of UV irradiance, were transferred to 85% sunlight, the flavonoid index exponentially increased, reaching a maximum within 10 days. On the whole, our experiments conclusively show that light-responsive flavonoids are mostly the dihydroxy B-ring-substituted structures. These flavonoids are the most effective, among the wide array of flavonoid structures, in preventing the generation and scavenging reactive oxygen species. As a consequence, we suggest that flavonoids do not merely serve as UV-screening agents, but behave as ROS-detoxifying agents in the mechanisms of photoprotection.

The interaction of the model flavonoid glycoside rutin with the flavonoid reagent diphenylborinic acid 2-aminoethyl ester (DPBA) was investigated using a combination of HPLC–DAD–ESI–MS analysis, UV–visible spectroscopy, and semiempirical calculations. Mass spectra and spectroscopic data made it possible to describe the complexation pathway as addition of diphenylboron groups to the two available 3′,4′-o-diphenolic and the 5-hydroxy-4-keto coordinating sites of rutin. Semiempirical calculations were carried out to obtain the conformation of the most stable DPBA/rutin adducts. The results showed that a number of complexation dynamics can occur as a function of the characteristics of the medium (type and pH of the solvent) and of the amount of DPBA. This work suggests the possibility of substantially improving existing procedures for recognition of flavonoid compounds by choice of suitable experimental conditions.

Background and Aims: Monitoring of anthocyanins (Anth) in winegrape (Vitis vinifera L.) is fundamental for the production of top-quality red wines. This work was aimed at testing a new fluorescence-based sensor for Anth detection in the vineyard. Significance of the Study: The present study showed a new important innovative technology for viticulture. The sensor evaluation of the large spatial and temporal heterogeneity in Anth accumulation can be useful as support parameter in the harvest date decision or for vineyard zoning of phenolic maturity. Methods and Results: Anth in grape (cv. Aleatico) bunches attached to the vine were monitored non-destructively in the field using a fluorescence-based sensor during the 2008 and 2009 seasons and under different water regimes. The ANTHRG index = log(far-red-fluorescenceR/far-red-fluorescenceG), with fluorescence signals excited with red (R) and green (G) light, was inversely correlated through an exponential function (r2 = 0.875) to the Anth concentration derived from the HPLC analysis of berry skin extracts. ANTHRG was effective in detecting the earlier ripening process in 2009 with respect to 2008 and differences in the Anth accumulation between seasons and in relation to different water regimes. Water deficit imposed in 2009 enhanced Anth concentration in berries because of a reduction in berry size but also an increase of Anth biosynthesis. This effect was observed by both destructive and ANTHRG non-destructive measurements. Conclusions: Our results show that the employed fluorescence sensor represents a reliable, rapid and non-invasive tool for monitoring and determining Anth accumulation in situ.

Artichoke (Cynara scolymus L.) is an edible vegetable largely used in the Mediterranean diet and in folk medicine. The present paper discusses the analysis of the polyphenol content of leaves and outer bracts of Violetto di Toscana artichoke using different extraction procedures with the aim of establishing a correlation between polyphenol subclasses and antioxidant activity measured on human LDL oxidized by copper ions. HPLC/DAD and HPLC/MS analyses revealed that both the matrixes contain identical polyphenol subclasses, with mainly quantitative differences. The antioxidant effect of four artichoke extracts decreases in the following order when the sum of total phenolic compounds was considered: ethanolic extract from leaves (IC50 = 2.92 ± 0.46 μM); ethanolic extract from outer bracts (IC50 = 4.04 ± 0.21 μM); ethyl acetate extract from leaves (IC50 = 4.91 ± 0.11 μM); ethyl acetate extract from outer bracts (IC50 = 10.18 ± 1.6 μM). IC50 were also calculated considering the concentrations of single polyphenol subclasses. In both cases, the potency of antioxidant properties was not related to the amount of total polyphenols or the single subclasses.

This work regards the characterization of the phenolic compounds and the mineral composition of the variety Violetto di Toscana, which is typically cultivated in Tuscany for the flavour of its edible part. All the results achieved are compared with those of var. Terom, which is widely used in Italy. A systematic study was performed on the different plant parts: the edible head and leaves, outer bracts and stems. The data for the whole plant showed that the polyphenol content of var. Violetto exceeds that of var. Terom by about 25%, so this variety could be regarded as a functional food and also as an interesting source of antioxidant phenolic compounds. A decoction of bracts and leaves was also carried out in order to evaluate the amount of polyphenols which may be extracted by a simple hot water extraction.

A rapid and inexpensive HPLC method has been developed for simultaneous separation of the three main classes of polyphenol in the leaves of Cistus salvifolius L. Time devoted to extraction of polyphenols, which was performed using small volume of solvent, did not exceed 120 min. We identified three ellagitannins (punicalagin and related compounds), a total of ten glycosyl derivatives of quercetin and myricetin, and two coumaroyl glucosyl kaempferols by use of both diode-array detection (DAD) and mass spectrometry. The polyphenol composition of C. salvifolius leaves, which may contribute to the metabolic plasticity of the species, may explain its distribution in infertile soils of the Mediterranean area, and may also indicate this shrub is an important source of metabolites of potential use in human health care.

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.

Virgin olive oil is a typical component of the Mediterranean diet, consumed unrefined and rich in important molecules, such as minor polar compounds (hydroxytyrosol, tyrosol, secoiridoids and flavonoids) and fatty acids. These molecules not only influence the sensorial properties of both olives and virgin oil but they are also important markers for typicity, biodiversity and quality determination of this product. The aim of this study was to evaluate the minor polar compound and fatty acid contents of 10 monocultivar virgin olive oils, typical of Tuscany, in order to have better knowledge about the quali-quantitative profiles of these compounds in samples obtained from both the same collecting season and same processing technique. Quali-quantitative analysis (performed by HPLC/DAD, HPLC/MS and GC) could be a useful tool to better correlate the typicity of the virgin olive oil with its minor polar compound and fatty acid pattern. Further studies are in progress to isolate the unknown compounds and to further investigate the quality index of this food product.

The antioxidant properties of galloyl quinic derivatives isolated from Pistacia lentiscus L. leaves have been investigated by means of Electron Paramagnetic Resonance spectroscopy (EPR) and UV-Vis spectrophotometry. Antioxidant properties have been also estimated using the biologically relevant LDL test. The scavenger activities of gallic acid, 5- O -galloyl, 3,5- O -digalloyl, 3,4,5- O -trigalloyl quinic acid derivatives, have been estimated against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide ( O 2 &#109 ) radical, and hydroxyl (OH) radical. On the whole, the scavenger activity raised as the number of galloyl groups on the quinic acid skeleton increased. The half-inhibition concentrations (IC 50 ) of di- and tri-galloyl derivatives did not exceed 30 &#119 M for all the tested free radicals. All the tested metabolites strongly reduced the oxidation of low-density lipoproteins (LDL), following a trend similar to that observed for the scavenger ability against OH radical.

Fruit quality compounds, such as antioxidant phenolics and chlorophyll, were assessed in situ by using a fluorescence method applied by a portable sensor. Indices of anthocyanins (ANTH) and flavonols (FLAV) localized on the fruit surface were obtained based on their screening of chlorophyll fluorescence excitation. The chlorophyll content was estimated by the far red to red chlorophyll fluorescence ratio (CHL index), due to the partial reabsorption of red fluorescence by chlorophyll itself. In kiwifruits, the CHL index was found to be well linearly correlated to the chlorophyll content determined by wet chemistry on the same fruit samples. Full sunlight exposed kiwifruits possessed a higher content of chlorophyll than shaded kiwifruits. This is an important parameter to know for assessing fruit quality and storability. Based on the estimation of the red-pigmented anthocyanins, we defined a new rapid method to determine the maturity level of olives after harvest, giving the proportion of red and green olives, important for the quality of the olive oil produced. In plums, ANTH and FLAV were found to be linearly correlated to the actual content of compounds measured by HPLC analysis of skin extracts. These indices can be, therefore, used to predict the phenolic antioxidant potential of plums and to define their maturity stage.

This work studies the possible functionalisation provided by natural dyes to wool fabrics against moths attacks. Wool flannel samples were dyed with extracts from Daphne gnidium L., Helichrysum italicum (Roth) G. Don, Rubia peregrina L., Castanea sativa Mill.. Tests on the textile resistance to mature larvae of T. bisselliella were performed together with the quantitative characterization of second metabolites of the plants extracts. The test allowed to preliminary elicit the contribute of natural dyes and mordants to protect wool textiles.

Lactuca sativa L. plants (cv. Audran) developed in greenhouse or in open air, were analysed for their polyphenol compounds (caffeic acid derivatives, quercetin and kaempferol glycosides) to verify whether these two different growing environments affected both the qualitative and quantitative phenol patterns. The lettuce extracts from greenhouse and open-air samples were compared and directly analysed by HPLC/DAD, HPLC/MS and HPTLC. All open-air samples had higher flavonol contents than the greenhouse ones. The applied rapid and sensitive HPTLC method could be routinely employed to determine the leaf flavonol content of a large number of lettuce samples.

Vitamin C behaves as a very powerful radical scavenger in aqueous media and can be successfully used to prevent peroxidation of important unsaturated organic molecules. Its hydrophobic derivatives (i.e. alkyl-esters and ethers) perform the same antioxidant activity in self-assembled structures such as micelles and microemulsion systems. In this work the study on the micellar properties obtained from these hydrophobic derivatives by viscosity, light-scattering, and small-angle neutron-scattering (SANS) experiments, and a comparison between the antioxidant activity of the vitamin C derivatives and the most common natural antioxidants are reported.

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.

Matricaria recutita L. is a spontaneous herbaceous perennial plant and its drug is largely used, as an infusion, for its anti-inflammatory properties, especially for respiratory and gastroenteric tracts. Granular soluble extracts of this drug are also used in children’s diets.

Hypericum perforatum L. is a spontaneous perennial herbaceous plant, widely distributed in Europe, Asia, Northern Africa, and North America. The dried flowers or dried aerial parts are used to prepare the drug Hyperici Herba or St. John's Wort. Nowadays this drug is largely used as a natural antidepressant; hypericin and hypericin-like substances are considered the main active ingredients. In this work the hypericin and pseudohypericin content of hydroalcoholic extracts both of Hyperici Herba and ofHypericum perforatum L. dried flowers were measured by two techniques, TLC-densitometry with fluorescence detection and reversed-phase HPLC-DAD (diode-array detection). The quantitative data obtained by applying these techniques were compared and the identification of the main flavonoid constituents was performed by HPLC-DAD for characterization of the extracts.

A liquid-solid extraction and purification procedure (LSE) was developed to identify and quantify polyphenols in the leaf tissue ofMyrtus communis L. Identification and quantitation of individual compounds was performed using HPTLC, HPLC-DAD and HPLC-MS analysis. Leaves ofMyrtus communis L. contain small amounts of phenolic acids (caffeic, ellagic and gallic acids) and quercetin derivatives (quercetin 3-O-galactoside and quercetin 3-O-rhamnoside), whereas catechin derivatives (epigallocatechin, epigallocatechin 3-O-gallate, epicatechin 3-O-gallate) and myricetin derivatives (myricetin 3-O-galactoside, myricetin 3-O-rhamnoside) are present in large amounts. This is the first report on the occurrence of galloyl-derivatives of catechin and gallo-catechin inMyrtus communis L. leaves.

Ultraviolet radiation (UVR) blocking properties of textiles depend on fibre type, fabric construction and nature of finishing chemicals. Natural dyes can provide vegetable fibres with strong colours if mordants are used. In this study UV protection properties of dyeing extracts from Mediterranean flora ( Helichrysum italicum Roth, Rubia peregrina L., Daphne gnidium L., Lavandula stoechas L., Cynara scolymus L.) were tested in combination with fabrics made of vegetable fibres (cotton and flax) and different types of mordants (potassium alum and chestnuts tannins). Pre- and post-dyeing solutions were analyzed quali-quantitatively by HPLC/DAD/ESI-MS in order to calculate the dye uptake on fabrics during the dyeing process. UVR transmittance of fabrics was measured using a spectrophotometer equipped with an integrating sphere. After the dyeing process only flax fabrics mordanted with alum and dyed with Lavandula and Rubia, and flax fabrics mordanted with tannin and dyed with Rubia and Helychrysum reached the minimum protection level. A very good protection level was reached by flax mordanted with alum and dyed with Helychrysum. Chestnut tannins provided a slight support in phenols uptake for Lavandula and Helichrysum plant dyes with respect to potassium alum, but without an improvement of the fabrics UV protection properties; flax samples dyed with Helichrysum extract showed an improvement in UV protection properties when mordanted with potassium alum instead of tannins. Colour fastness and the persistence of UV protection characteristics were also tested after light/sun exposure and after several washes.

The safest protection from UV radiation (UVR) exposure is provided by clothing and depends on fabric composition (natural, artificial or synthetic fibers) and parameters (porosity, weight and thickness), as welI as dyeing methods and properties (natural or synthetic dyes, dye concentration, UV absorbing properties, etc.). UV protection properties of dyes extracts from Rubia peregrina L, Daphne gnidium L., Helichrysum italicum L. , Lavandula stoecas L. applied with two different mordants (potassiurn alum and chestnut tannins) were investigated on flax and cotton fabrics. D. gnidium L. and H italicum L. extracts were also applied on wool fabric to test textile resistance to mature larvae of T bisselliella and the oviposition deterrence activity.

Kiwifruit contains high amounts of anti-oxidants beneficial to health. Its quality is influenced by ripening time, genotype, cultivation techniques, climate and storage conditions after harvest.The aim of the present study was to characterise the phenolic content by HPLC methods and to evaluate the performance of a portable optical sensor (Multiplex 3), for in vivo non-destructive phenolic compound assessment in kiwifruits.Kiwifruits peel extracts were characterised by reverse-phase (RP) HPLC with diode-array detector (DAD) and electrospray ionisation (ESI) with MS using the Zorbax SB-Aq. column from Agilent. The fluorimetric sensor method is based on the screening of fruit chlorophyll fluorescence excitation and allows the UV absorbance of intact fruit skin to be measured. The flavonol index, FLAV, was calculated as log(FRF(R)/FRF(UV)), where FRF(R) and FRF(UV) are the chlorophyll fluorescence excited with red and UV light.Hydroxycinnamic acids, procyanidins, and quercetin glycosides were the main polyphenol classes detected by HPLC-DAD-ESI/MS in the kiwifruit skin. A good linear regression (R² = 0.88) was found between the fluorimetric sensor FLAV index and flavonol chromatographic analysis of the fruits. The FLAV index was able to detect the higher content of flavonols in sun-exposed fruits with respect to mid-shaded and shaded ones in accordance with the destructive analysis.The fluorimetric sensor represents a rapid and non-invasive tool to: (i) monitor the flavonol accumulation in kiwifruit and to assess its quality concerning the healthy anti-oxidant properties; (ii) evaluate the effect of environmental and agronomical factors related to the fruit quality; and (iii) select fruits with the largest flavonol content, and consequently less susceptible to pathogen attack, in order to improve their storage durability.

In the fresh tissues of Prunus mahaleb L., three classes of phenolics were characterised: phenolic acid derivatives (main compound being o-coumaric acid glucoside), quercetin glycosides, and anthocyanins (cyanidin 3,5-diglucoside, cyanidin 3-sambubioside, cyanidin 3-xylosyl-rutinoside and cyanidin 3-rutinoside). Coumarin was also identified. The kernels showed a high content of coumarin (0.87 mgg(-1)) which is the main class of metabolites in this sample, but present in pitted berries as well (0.63 mgg(-1)). Flavonoids are mainly concentrated in the skin and pulp (0.55 mgg(-1)). In 'Mirinello di Torremaggiore' liqueur, produced from P. mahaleb L. in accordance with traditional procedures, anthocyanins make up 16.5%, phenolic acids 43.3%, coumarin 36.2% and flavonoids 4% of total compounds. Anthocyanins are the main class in solid residues from liqueur production (70%). These findings point out that solid residues of P. mahaleb can be considered an interesting and innovative source of appreciable amounts of cyanidin glycosides (3.3 mgg(-1)).

En Italie, au cours des dernières cinquante années, les régions rurales ont enregistré un de forte dépopulation due aussi à un modèle d'agriculture intensive très spécialisé, qui a été l'une des raisons de l'abandon de la campagne et de la conséquente destruction de la ruralité comme valeur environnementale et sociale, de la perte généralisée de la biodiversité et de la pollution (Meloni, 2006). Au côté de ce phénomène, l'adoption par les résidents ruraux de certains caractères de la culture urbaine, selon un processus dénommé d'acculturation, a conduit à une perte de la culture de l a «tradition» (Ember et Ember, 1997). Par conséquence, dans les régions méditerranéennes, on a vu la disparition progressive de la relation entre la culture populaire et la nature, un lien qui survécu principalement grâce à l'utilisation alimentaire et médicinale des plantes (Hadjichambis et al., 2008)

Hydrolysable tannins (HTs), secondary metabolites widely distributed in the plant kingdom, are generally multiple esters of gallic acid with glucose. HTs have been shown to be effective antagonists against viruses, bacteria and eukaryotic microorganisms. The present review examines the antimicrobial and antiviral activity of HTs, the mechanism(s) of action, and some structure-activity relationships.

The role of flavonoids in the response of plants to Plasmopara viticola, the phytopathogen agent of downy mildew, was studied in the Vitis vinifera L. cultivar Sangiovese. Grapevines in the vineyard were exposed to two light regimes, 100% and 35% of full sunlight in order to induce differences in total leaf polyphenolic content. Epidermal leaf phenolic compounds were assessed optically, using the Dualex chlorophyll fluorescence-based portable leaf-clip. Dualex data were calibrated by means of HPLC analysis of extracts from the same measured leaves. Good correlations were obtained with total flavonoid contents, which consist mainly of quercetin 3-O-glucuronide. From the Dualex non-destructive measurements, we showed that full-sun exposed leaves contained 75% more flavonoids than shaded leaves. Inoculation of leaves with P. viticola sporangia resulted in a significantly lower infected leaf area in sun-lit leaves compared with shaded ones, as seen from subsequent analysis of the downy mildew severity. These results indicated an inverse relationship between preformed flavonoids and the susceptibility of grapevines to downy mildew. The rapid optical method for the non-destructive assessment of flavonoids presented here could be useful for large scale screening and predicting V. vinifera susceptibility to P. viticola.

Cynara cardunculus is a diploid (2n = 2x = 34) species, native to the Mediterranean basin, which belongs to the family of Asteraceae. It includes globe artichoke, cultivated cardoon, as well as their progenitor wild cardoon. The species is a source of biophenols and its leaf extracts have been widely used in herbal medicine as hepatoprotectors and choleretics since ancient times. Globe artichoke leaves have been found to be rich in compounds originating from the metabolism of phenylpropanoids however, to our knowledge, the leaf polyphenolic composition of the two other forms within the species, cultivated and wild cardoon, have not yet been properly investigated. Two main classes of polyphenols have been detected by HPLC/DAD and HPLC/MS analyses: caffeoyl esters and flavonoids. The compounds which are the result of esterification of caffeoylquinic acid moiety with succinic acid, previously detected in other members of the Asteraceae family, were detected in cardoon leaves for the first time.

• Salt- and light-induced changes in morpho-anatomical, physiological and biochemical traits were analysed in Myrtus communis and Pistacia lentiscus with a view to explaining their ecological distribution in the Mediterranean basin. • In plants exposed to 20 or 100% solar radiation and supplied with 0 or 200 mM NaCl, measurements were conducted for ionic and water relations and photosynthetic performance, leaf morpho-anatomical and optical properties and tissuespecific accumulation of tannins and flavonoids. • Net carbon gain and photosystem II (PSII) efficiency decreased less in P. lentiscus than in M. communis when exposed to salinity stress, the former having a superior ability to use Na + and Cl – for osmotic djustment. Morpho-anatomical traits also allowed P. lentiscus to protect sensitive targets in the leaf from the combined action of salinity stress and high solar radiation to a greater degree than M. communis . Salt and light-induced increases in carbon allocated to polyphenols, particularly to flavonoids, were greater in M. communis than in P. Lentiscus, and appeared to be related to leaf oxidative damage. • Our data may conclusively explain the negligible distribution of M. communis in open Mediterranean areas suffering from salinity stress, and suggest a key antioxidant function of flavonoids in response to different stressful conditions.