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Grape seeds (GS) are one of the most important by-products of the winery and grape juice industry. GS contain a vast array of health-giving metabolites, including several polyphenols known for their remarkable antioxidant activity. In this study, it has been evaluated the nutraceutical potential of seeds from 15 grapevine cultivars/clones in terms of total phenols, monomeric, dimer, polymeric, gallate esters flavan 3-ols composition andin vitroantiradical activity. Considerable quali-quantitative differences in polyphenol content and AA had been observed among GS from different cultivars/clones collected in 2013 and 2014. In most of the investigated cultivars/clones, the better values of TP, FL and AA were recorded in GS collected in 2014. The polymeric procyanidins were significantly higher in 2014 in all the cultivars, while the gallate esters were significantly higher in 2013. These differences can be attributed to different climatic conditions in 2013 and 2014. In conclusion, the data here reported help to identify the best source of GS for the recovery of bioactive polyphenols and to valorize these waste materials. [ABSTRACT FROM PUBLISHER]

In this study, the aim was to evaluate the antimicrobial action of the non-volatile phenols of rosemary leaves against two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and two Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis). Three extracts with different phenolic compositions were tested. By the agar disc diffusion method, Gram-positive bacteria were more sensitive to the extracts, and S. epidermidis showed the highest inhibition zones. Overall, all the extracts tested by the broth dilution method showed higher activity than results from the agar disc diffusion method. The minimal bactericidal concentration values indicated that E. coli was the most susceptible strain. This study demonstrated that the flavonoidic fraction of rosemary leaves does not play a crucial role as antimicrobial agents against these microorganisms. The most active extract was characterised by the highest amount of non-volatile terpenoidic compounds. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effect of stilbenes from different cultivars ofVitis viniferaon tumour proliferation. Extracts were obtained from elicitedV. viniferacell cultures and characterised by HPLC/DAD/MS. Cell growth was evaluated in four human cancer cell lines and in normal human fibroblasts. The cells were exposed to the extracts or totrans-resveratrol, used as reference molecule, for 48 h, at 1–10 μM concentrations of total stilbenoids. All the extracts exhibited antiproliferative activity, mediated by modulation of the cell cycle and induction of cytotoxicity in cancer but not in normal cell lines, and positively correlated with the content in dimeric stilbenoids. The Alphonse Lavallée extract was the most active, and the obtained stilbenoid fraction resulted 8–10 times more active thantrans-resveratrol. Extracts fromV. viniferacell cultures could represent new sources of active stilbenoid compounds to be further assayed inin vivostudies for their antitumoural properties. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

An HPLC-ESI-MS method in a positive mode is proposed to qualitatively analyse the saponin fractions from dietary supplements of Tribulus terrestris L. This method allows for theseparation of structural isomers, as highlighted for some terrestrosines. The MS fragmentation pattern resulted diagnostic to collect structural information and the characteristic loss of water from some furostanolic saponins was highlighted for the first time. Due to the wide number of glycosidic furostanolic and spirostanolic saponins extracted from tribulus, a complete reference “molecular weight map” was created. Finally, a seml-quantitative evaluation of the total saponin content was carried cut by HPLC-MS using protodioscin as external standard. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to obtain qualitative and quantitative profiles of the flavonoid and biflavonoid composition of six cypress species— Cupressus funebris L., Cupressus sempervirens L., Cupressus glabra L., Cupressus arizonica L., Cupressus goveniana L., and Cupressus lusitanica L. HPLC-diode-array detection (DAD), HPLC-MS, and HPTLC were used to identify the individual compounds. A chromatographic method was optimized for identification and quantification of the main flavonoid glycosides and biflavonoids. The flavonoids identified and calibrated were: rutin, quercetin glucoside, quercetin rhamnoside, and kaempferol 3- O-rhamnoside. The biflavonoids identified and calibrated were: cupressuflavone, amentoflavone, robustaflavone, hinokiflavone, methylrobustaflavone, methylamentoflavone, and dimethylcupressuflavone. [ABSTRACT FROM AUTHOR]

The aim of this work was to contribute to the phytochemical characterization of Cichorium intybus L. var. silvestre, chicory. Semi-preparative HPLC analysis was applied to an extract of fresh wild chicory leaves to separate and collect the main polyphenolic compounds. HPLC-diode-array detection (DAD), HPLC-MS, and NMR were used for the complete chemical characterization of all the compounds isolated. The molecules characterized were monocaffeoyl tartaric acid, chicoric acid, monocaffeoly p-hydroxycinnamoyl tartaric acid, caffeoyl feruloyl tartaric acid, chlorogenic acid, quercetin-3- O-glucuronide, luteolin-7- O-glucuronide, and quercetin-3- O-glucoside. The chromatographic behaviour of the main components of the extract of the leaves has been compared on three different stationary phases-LiChrosorb RP18, Luna C18, and Luna Phenyl-Hexyl. [ABSTRACT FROM AUTHOR]