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In this work, the ability of pine bark procyanidins to hinder oxidation in bulk corn oil and corn oil‐in‐water‐emulsion has been investigated. A preliminary characterisation of the obtained aqueous (AF) and organic (OW) fractions and subfractions suggested a very polar character and showed that both fractions possess remarkable antioxidant activity when minimum concentrations of 2 mg/mL are used. OW fractions and subfractions derived from both pine varieties were able to inhibit oxidation in oils. More specifically, two organic subfractions were the most efficient for retarding the degradation process, with levels of 62% and 50% after 8 days of treatment, respectively. Organic subfractions obtained from both varieties of pine also rendered possible inhibition levels in oil‐in‐water‐emulsions up to 80% after 4 days of oxidation, more than 3 times higher than the levels provided by tocopherol, a well‐known model commercial antioxidant, which confirms the excellent antioxidant potential of procyanidins from pine bark. Practical application: Lipid deterioration leads to losses in quality and nutritional value and to the development of off‐flavours in many foodstuffs. One way to overcome this drawback is by using antioxidants of natural origin, which is a subject of a great scientific and industrial interest, reflected by the growing number of papers and patents published during the last years. Since aqueous and organic fractions obtained from Pinus pinaster and Pinus radiata bark turned out to be an adequate source of procyanidins in previous investigations of our group, their possible antioxidant role in model lipid systems was investigated. This approach entails also another benefit in terms of waste valorisation, since pine bark is a typical residue of agroforestal industries.

Pine bark is an important source of polyphenolic compounds, mainly procyanidins, with reported protective effects against disease. In previous works, barks of two varieties of pine (P. pinaster and P. radiata) were extracted with ethanol, and partially purified to obtain the aqueous fractions (FA), that contained mainly polymeric procyanidins. The mean degree of polymerization was 7.9 for radiata (rFA) and 10.6 for pinaster (pFA). FAs were chromatographed on Sephadex LH-20 by using a gradient of methanol, water and acetone, to render a series of sub-fractions. In this work, the procyanidin compositions of these sub-fractions were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The mass spectra of sub-fractions from FA of P. pinaster showed signals of procyanidin polymers up to tridecamers, whereas for those from P. radiata the maximum degree of polymerization was 15. For this latter case, the MALDI-TOF mass spectra detected the presence of prodelphinidins in a small amount.

Pine bark is a forest by-product that can be profitable as a source of polyphenols by its content in procyanidins. In this work, barks of two varieties of pine (Pinus pinaster and P. radiata) were extracted with ethanol, and partially purified to obtain a fraction named FOW, that contained mainly flavan-3-ol monomers and procyanidins oligomers. The mean degree of polymerization was 2.1 for pinaster (pOW) and 2.7 for radiata (rOW). FOWs were fractionated on C18 Sep-Pak cartridges into three fractions for each variety by different organic solvents. The phenolic compositions of the fractions were analyzed using HPLC with UV diode array detection and electrospray-ionization mass spectrometry. The compounds identified were: catechin, dihydroquercetin, phenolic acids and their glucosides, procyanidins dimers, trimers and tetramers. FOWs and their fractions were characterized in antioxidant power by DPPH and β-carotene methods. In the former assay, pOW showed major effectiveness, with an antiradical specific activity of 46 units AR/mg procyanidins, whereas for the β-carotene bleaching test rOW (78 ± 0.71%) gave the best inhibition result. Despite this fact the derived fractions, presenting similar values, have advantages because the profile of their constituents is uniform for each one, and, hence, it is easier to investigate their action for potential applications in both medical or food fields

5 pages, 4 tables.-- Printed version published Feb 2007., The composition and antiradical activity of procyanidins from the bark of two kinds of pine, Pinus pinaster and Pinus radiata, were compared. Both the total bark extract and the fraction soluble in both water and ethyl acetate (OW) were evaluated, because of their promising results in previous experiments., Results showed that P. radiata bark was richer in total phenols and also in procyanidins, catechin always being the main unit, so terminal as extensional. For P. pinaster, epicatechin was the predominant extension unit. The mean degree of polymerization (mDP) was higher for the latter. Interestingly, opposite results were encountered for the corresponding OW fractions, where P. radiata showed a mDP of 2.9 vs. 2.3 of P. pinaster. It was also found that the higher the mDP the higher was the specific antiradical activity. The different procyanidin composition and specific antiradical activity of the two kinds of barks, and particularly their OW fractions, may lead to the design of efficient natural antioxidants with application in the food industry., We thank the Spanish Ministry of Science and Technology for Project No. PPQ2003-06602-C04, Subprojects 1 and 2.

10 pages, 5 figures.-- Printed version published Feb 2007., Barks of Pinus pinaster and Pinus radiata were studied as source of procyanidins; these raw materials, considered a byproduct of forestal industry, were extracted with ethanol. The extract was partially fractionated to obtain an aqueous fraction (FA) containing a great part of the procyanidins from barks and with potential application to both food and medical fields. FAs were rich in polyphenols, 65–87% of which were procyanidins; the mean degree of polymerization (mDP) was 7.9 for radiata (rFA) and 10.6 for pinaster (pFA) varieties., The aqueous fractions were chromatographed on Sephadex LH-20 to obtain specific fractions differing in DP and composition. These fractions were analysed by thiolysis with cysteamine, followed by RP-HPLC. Results showed that (+)-catechin was the main terminal unit for both barks and also the main extension unit for radiata. In contrast (-)-epicatechin was predominant as extension unit in pinaster and this could have implications for applications in oils, emulsions and biological systems., In terms of antiradical activity, expressed as specific antiradical units, the entire rFA gave the best results, together with rF5. For P. pinaster bark, the best results were achieved for fractions F5–F8, with DP 7–22. The whole fraction from radiata represents an economic alternative of great interest because the fractionation costs can be avoided., We thank Spanish Ministry MCyT for Project PPQ2003-06602-C04-01 and 02.

Grape byproducts were subjected to an extraction process under various different experimental conditions (namely, solvent type, temperature, solvent-to-solid ratio, time contact, and raw material) in order to study the effect of these conditions on the yield of phenolic compounds and the corresponding antiradical activity of extracts. Although the order of decreasing capacity to extract soluble materials was ethanolmethanolwater, methanol was the most selective for extracting phenolic compounds. Temperature and solvent-to-solid ratio were found to have a critical role in extraction efficiency; values of 50 degrees C (between 25 and 50 degrees C) and 1:1 (between 1:1 and 5:1) maximized the antiradical activity of phenolic extracts. In addition, extracts from grape samples previously subjected to distillation reached higher antiradical values in comparison to those coming directly from pressing; in both cases, seed extracts showed better results than those of stem when ethanol or water was employed, whereas the opposite occurred in the case of methanol. These differences were attributed to the different phenolic compositions of the considered fractions.

PURPOSE: To identify the presence of silver deposits in the cornea using a new-generation confocal microscopy technique. METHODS: Case report. RESULTS: A 70-year-old man, who had been a jeweler for many years, was referred to our center for assessment of corneal opacity and ocular pigmentation. Slit-lamp examination revealed grayish, dense confluent deposits in the central and peripheral cornea, deep stroma, and Descemet's membrane. On confocal microscopy, we observed typical images of hyperreflective keratocytes across the entire stromal surface and two hyperreflective plaques coinciding with areas of metal deposition, one at Descemet's membrane and the other at Bowman's membrane. This last deposition site has not been previously identified in vivo by confocal microscopy. CONCLUSIONS: Confocal microscopy is a useful tool for the diagnosis of corneal argyrosis because it allows the in vivo visualization of silver deposits at different corneal levels.

Procyanidins have been associated with a reduced risk of cardiovascular diseases such as atherosclerosis. However, the molecular mechanisms underlying this benefit are not fully understood. Increased reactive oxygen species (ROS) production generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is a common problem in different cardiovascular diseases. Our objective was to evaluate the effects of procyanidin-rich fractions from distilled grape pomace on NADPH oxidase activity in human umbilical vein endothelial cells (HUVEC). Three differently polymerized and galloylated procyanidin fractions were analyzed for their NADPH oxidase inhibitory activity in cell lysates and in HUVEC cultures. All of the three fractions, up to 1 µg/ml, equally inhibited isolated NADPH oxidase in HUVEC lysates in a concentration-dependent manner and independently of any superoxide anion scavenging activities. The procyanidin fractions even blocked NADPH oxidase activity in intact HUVEC, inhibiting ROS production at both extra- and intracellular levels. The fractions achieved the same effects that known NADPH oxidase inhibitors, such as diphenylene iodonium and apocynin, but they presented better hydrosolubility. Our results demonstrated that procyanidin from grape pomace inhibit human endothelial NADPH oxidase regardless of their polymerization degree and galloylation percentage. Therefore, procyanidins are suitable NADPH oxidase inhibitors which could serve as models for therapeutic alternatives for cardiovascular diseases. J. Cell. Biochem. 113: 1386–1396, 2012. © 2011 Wiley Periodicals, Inc.

The influence of technological factors (decaffeination, brew volume, coffee species, and roast degree) on antiradical activity and phenolics content of espresso coffee is described. The screenings of phenolics profile and other compounds (caffeine and trigonelline), as well as the quantification of hydroxymethylfurfural, were performed by LC-DAD-ESI-MS. Significantly lower (p0.05) scavenging activities and phenolics contents were found in decaffeinated espressos when compared with regular ones (32 vs 38% and 324 vs 410 mg/30 mL cup, respectively). A long espresso (70 mL) offers more than twice the phenolics amount of a short one (20 mL). Robusta brews showed higher (p0.05) antiradical activity and phenolic contents than arabica ones, for all roast degrees (light, medium, and dark). No significant differences (p0.05) were observed for scavenging activities of differently roasted robusta brews, whereas an increase in medium-dark brews was observed for arabica samples. Total phenolics in robusta espressos decreased (p0.05) with the increase of roast degree, but no significant differences (p0.05) were found between arabica espressos from different roasts. By LC-DAD-ESI-MS, 23 hydroxycinnamic derivatives were found, including chlorogenic acids, lactones, and cinnamoyl-amino acid conjugates. The amount of each compound was differently affected by species and roast. Robusta brews presented superior levels of caffeine and chlorogenic acids, whereas arabica ones contained more trigonelline. Hydroxymethylfurfural contents in the brew (30 mL) varied from 2.60 to 0.84 mg for light- and dark-roasted arabicas and from 1.29 to 0.68 mg for light- and dark-roasted robustas, respectively.

Pinus pinaster extract is a polyphenol-rich food supplement containing diverse types of flavonoids. The latter are known to have strong antiradical activity and thus different beneficial effects on human health. A 23 experimental design was performed to study the effect of temperature, contact time and liquid–solid ratio on the ethanol extraction efficiency. High values of phenol yields (17.0 ± 0.00 eq. g gallic acid/l) and antiradical activity (85.6 ± 3.94 DPPH inhibition percentage) were detected at 50 °C (values varied between 25 and 50 °C), at 90 min (between 30 and 90 min) and at a 5:1 liquid–solid ratio (between 5:1 and 10:1). A subsequent HPLC analysis allowed identification of the phenols occurring in the extracts. Previously, an aqueous extract (A), and another one soluble in both water and ethyl acetate (OW), were obtained after fractionation and subjection to thiolysis. The main monophenols detected were catechin > epicatechin in the A fraction and dihydroquercetin > catechin > epicatechin in the OW one. In the former fraction, the average degree of polymerization ( DPn ¯ ) of procyanidins was 7.0, while only oligomer phenols with DPn ¯ = 3 . 0 were found in the OW fraction.