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The Rosmarinus officinalis L. is widely known for its numerous applications in the food field but also for the increasing interest in its pharmaceutical properties. Two groups of compounds are mainly responsible for the biological activities of the plant: the volatile fraction and the phenolic constituents. The latter group is mainly constituted by rosmarinic acid, by a flavonoidic fraction and by some diterpenoid compounds structurally derived from the carnosic acid. The aim of our work was to optimize the extractive and analytical procedure for the determination of all the phenolic constituents. Moreover the chemical stability of the main phenols, depending on the storage condition, the different drying procedures and the extraction solvent, have been evaluated. This method allowed to detect up to 29 different constituents at the same time in a relatively short time. The described procedure has the advantage to being able to detect and quantify several classes of compounds, among them numerous minor flavonoids, thus contributing to improving knowledge of the plant. The findings from this study have demonstrated that storing the raw fresh material in the freezer is not appropriate for rosemary, mainly due to the rapid disappearing of the rosmarinic acid during the freezing/thawing process. Regarding the flavonoidic fraction, consistent decrements, were highlighted in the dried samples at room temperature if compared with the fresh leaf. Rosmarinic acid, appeared very sensitive also to mild drying processes. The total diterpenoidic content undergoes to little changes when the leaves are freeze dried or frozen and limited losses are observed working on dried leaves at room temperature. Nevertheless it can be taken in account that this fraction is very sensitive to the water presence during the extraction that favors the conversion of carnosic acid toward it oxidized form carnosol. From our findings, it appear evident that when evaluating the phenolic content in rosemary leaves, several factors, mainly the type of storage, the drying process and the extraction methods, should be carefully taken into account because they can induce partial losses of the antioxidant components. © 2011 Elsevier B.V. All rights reserved.

HPLC/DAD/MS analysis of the phenolic acids and anthocyanin content of three cultivars of Solanum tuberosum L. (Vitelotte Noire, Highland Burgundy Red, with pigmented flesh, and Kennebec with white pulp) was performed. The analyses were carried out both on fresh tubers and after cooking treatments (boiling and microwaves). Starch digestibility and the % of resistant starch were also determined on cooked tubers by in vitro methods. For the pigmented potatoes, the heating treatment did not cause any changes in the phenolic acids content, while anthocyanins showed only a small decrement (16-29%). The cv. Highland Burgundy Red showed anthocyanins and phenolic acid concentrations close to 1 g/kg and more than 1.1 g/kg, respectively. Vitellotte Noire showed the highest amounts of resistant starch. Potato starch digestibility and % of resistant starch, considered as a component of dietary fiber, were affected both by cultivar and by heating/cooling treatments.

The aim of the present study was to verify the distribution of lignans in pulp and stones of olive fruits. Analyses were carried out by HPLC/DAD/MS on four cultivars: Frantoio and Taggiasca from Italy, Arbequina and Picual from Spain. The main results can be summarized as follows: (a) lignans were demonstrated to be present in the stone; (b) acetoxypinoresinol, pinoresinol, previously detected in the respective extra virgin olive oils, and OH-pinoresinol were found in the samples; (c) the total lignan content ranged between 0.1 and 0.29 mg/g of dried stone weight. These values agree with the average lignan content reported in literature for the respective extra virgin olive oils.

The aim of the present study was to compare the phenolic content in selected monocultivar extra virgin olive oils. Analyses were carried out by HPLC/DAD/MS on Picual, Picuda, Arbequina and Hojiblanca oils from Spain and Seggianese and Taggiasca oils from Italy. Oils from cultivar Picual showed similar characteristics to those of Seggianese oils, with total amounts of secoiridoids of 498.7 and 619.2mg/L, respectively. The phenolic composition of Arbequina oils is close to that of the Taggiasca variety with lignans among the main compounds. The determination of free and linked OH-Tyr, by way of an acid hydrolysis, represents a rapid and suitable method, especially when standards are not available, to determine antioxidant potentialities in terms of MPC, particularly for fresh extra virgin olive oils rich in secoiridoidic derivatives.

We describe chemical hydrolytic procedures to evaluate the total amount of tyrosol and hydroxy-tyrosol free and/or linked to secoiridoidic molecules (acid hydrolysis). At the same time a rapid determination of the lignans in complex minor polar compound (MPC) extracts is proposed (alkaline hydrolysis). High-performance liquid chromatography/diode array detection (HPLC/DAD) and HPLC/MS were applied as reference methods to evaluate the quantitative results from the hydrolysis experiments. The optimized acid hydrolysis procedures were first applied to an oleuropein standard and then to MPC fractions extracted from several commercial extra virgin olive oils. The results confirm the applicability of the method, consisting in the acid hydrolysis of complex mixtures of secoiridoidic derivatives, to determine the antioxidant potential in terms of MPC. These data can contribute to forecasting the potential ageing resistance of an extra virgin olive oil in terms of antioxidant potency. Finally, alkaline hydrolysis allows confirmation and easy determination of the amount of lignans, especially in those MPC fractions which are particularly complex. Copyright © 2006 Society of Chemical Industry

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.

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 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.

This paper focuses on comparing the main chemical characteristics of 16 fresh commercial samples of extra virgin olive oil obtained from four harvest years (1999–2002) and derived from both stoned and whole fruits. The qualitative and quantitative contents of minor polar compounds (MPCs) together with other reference analytical parameters (acidity, peroxides, UV absorption values and Rancimat test) were evaluated. An investigation of the MPCs and oil composition obtained from only stoned olives was also carried out. The acidity values of the oils from stoned fruits were always similar to or lower than those of the corresponding oils from whole fruits. For almost all the samples from stoned olives a better resistance to oxidation was revealed in comparison with the corresponding traditional oils. Five pairs obtained from the 2000 and 2001 harvests showed higher concentrations of both MPCs and hydroxytyrosol derivatives in the oils from stoned fruits, in agreement with their higher Rancimat values. Overall, our findings with regard to acidity values, % hydrolysis, the Rancimat test and the qualitative and quantitative distribution of MPCs suggest a higher antioxidant capacity of the oils from stoned olives. Copyright © 2004 Society of Chemical Industry

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.

The objective of the present study was to evaluate the amount of some potential health-promoting phenols in the grape of Vitis vinifera cv. Cesanese d'Affile and in wines made from these grapes. The analyses were performed using HPLC/DAD/MS. The accumulation of anthocyanins in the skin and flavan-3-ols in the seed was determined at different stages of ripening of the grape (i.e. green, veraison, middle stage of ripening, and complete ripening). Thirteen anthocyanins were identified in the skin at all stages of ripening, except the green stage. With regard to flavan-3-ols, (+)-catechin, (-)-epicatechin, and (-)-epicatechin gallate were detected in all of the seed samples. The highest (+)-catechin content was found in the seeds of the green grape (2 mg g(-1) DW), whereas in the seeds from the completely ripe grape the content was more than ten times lower. The highest catechin content in the seed was correlated with the lowest anthocyanin content in the skin. The wines produced in the years 2004 and 2005 showed, at wavelengths of 520 and 280 nm, almost identical quali-quantitative chromatographic profiles, with high concentrations of anthocyanin 3-O-glucosides, low concentrations of acylated anthocyanins, and trace amounts of (+)-catechin and (-)-epicatechin.

The aim of the present work was to develop a quali-quantitative investigation, using HPLC/DAD and HPLC/ESI/MS techniques, of the phenolic composition of berries collected from wild Tuscan plants of Juniperus communis L. and grown in three different geographical zones. The applied chromatographic elution method made it possible to well separate up to 16 different compounds belonging to flavonoids, such as isoscutellarein and 8-hydroxyluteolin or hypolaetin glycosides, and six biflavonoids, among them amentoflavone, hynokiflavone, cupressoflavone, and methyl-biflavones. To the best of the authors' knowledge this is the first report on the presence of these compounds in juniper berries. The flavonoidic content in the analyzed berries ranged between 1.46 and 3.79 mg/g of fresh pulp, whereas the amount of the biflavonoids was always lower, varying between 0.14 and 1.38 mg/g of fresh weight.

The present paper reports on the production of anthocyanins and xanthones in different in vitro systems of Hypericum perforatum var. angustifolium (sin. Frohlich) Borkh. Undifferentiated calli and regenerated shoots at different developmental stages were analyzed by applying an extractive and an analytical procedure capable of detecting and quantifying anthocyanins. The findings revealed, for the first time, the co-presence of hypericins and anthocyanins in shoots at initial and more developed stages of H. perforatum var. angustifolium L. Moreover, a high production of xanthones was found in the undifferentiated calli.

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.

The anthocyanic composition of Amorphophallus titanum (Becc.) Becc. ex Arcang. (Syn. Titan Arum), a plant growing only in the equatorial tropical rainforests of Sumatra, has been investigated for the first time. Spathe, spadix and female flowers were analysed and cyanidin-3-glucoside and cyanidin-3-rutinoside (which represent about 97% of the total anthocyanin content) were identified by HPLC and HPLC–MS analysis. Traces of peonidin and pelargonidin p-coumaroyl glucosides were also detected.

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.

The phenolic profiles are presented of four tropical green leafy vegetables ( Ocimum gratissimum, Vernonia amygdalina, Corchorus olitorius and Manihot utilissima) commonly used as food, after application of traditional treatments, such as boiling and abrasion. The HPLC/DAD/MS technique was mainly used to carry out this study. Preliminary evaluation of the antioxidant properties of the vegetables was also performed using the DPPH in vitro test. For the first time, seasonal variations in the phenolic content of the four investigated vegetables were highlighted. Of the four plants, all showed only quantitative differences, except for Ocimum graticimum, in which cichoric acid, previously detected as one of the main constituents of this vegetable collected in November (dry season), was absent in the sample harvested in March. The phenolic constituents are chemically unmodified after a strong heating process, such as the traditional blanching (about 15 minutes) applied by Nigerian people prior to consuming these vegetables. Nevertheless, these typical preparations showed a consistent decrease in the total phenolic compounds with respect to the raw material, particularly for Corchorus olitorius (from 42.3 to 5.56 mg/g dried leaves) and Vernonia amygdalina (from 40.2 to 4.4 mg/g dried leaves). As expected, when the blanching treatment is reduced to a few minutes, as for Manihot utilissima leaves, the cooked vegetable maintained almost unaltered its original phenolic content (around 10 mg/g dried leaves). The unique exception is the blanched Ocimum gratissimum sample that showed a consistent increment of the total phenols, particularly of rosmarinic acid (from 6.1 to 29.8 mg/g dried leaves) with respect to the unprocessed vegetable.