Procyanidin-rich extract from grape seeds prevents cataract formation in hereditary cataractous (ICR/f) rats

Antioxidants such as vitamin C, vitamin E, and carotenoids have been reported to prevent the progression of experimentally induced cataracts. However, little is known of the effect of procyanidins, a powerful antioxidant, on cataract formation. This paper investigates the anticataract activity of grape seed extract (GSE, which contains 38.5% procyanidins) in hereditary cataractous rats (ICR/f rats). The ICR/f rats were fed a standard diet containing 0 or 0.213% GSE [0.082% procyanidins in the diet (w/w)] for 27 days. The GSE significantly prevented and postponed development of cataract formation by evaluation of slit lamp observations of the rats' eyes. Lens weight and malondialdehyde concentration in the lens and plasma cholesteryl ester hydroperoxide (ChE-OOH) level induced by CuSO4 were significantly lower in the GSE group compared with the control group. The rats were also fed for 14 days either the diet containing 0.085% procyanidin dimer to tetramer fraction (0.085% as the procyanidins), the diet containing 0.090% procyanidin pentamer to heptamer fraction (0.085% as the procyanidins), or the diet containing 0.093% procyanidin oligomers more than decamer fraction (0.085% as the procyanidins). The ChE-OOH levels in the procyanidin pentamer to heptamer and procyanidin oligomers more than decamer groups were significantly lower than in the procyanidin dimer to tetramer group. These results suggested that procyanidins and their antioxidative metabolites prevented the progression of cataract formation by their antioxidative action. The larger molecular procyanidins in the GSE might contribute this anticataract activity.     

Phenolic acids are in vivo atheroprotective compounds appearing in the serum of rats after blueberry consumption

Blueberries (BB) have recently been shown to have cardioprotective effects and to prevent atherosclerosis in rodent models. However, the bioactive compounds in BB responsible for these effects have not yet been characterized. Seven phenolic acids (7PA) were identified as metabolites in the serum of rats fed diets supplemented with 10% freeze-dried BB. In this study, 7PA were evaluated for their potential atheroprotective effects in murine macrophage cell line RAW 264.7. 7PA were found to inhibit LPS-induced mRNA expression and protein levels of pro-inflammatory cytokine TNF-α and IL-6 by reducing MAPK JNK, p38, and Erk1/2 phosphorylation. After treatment with 7PA for 2 weeks, mRNA expression and protein levels of scavenger receptor CD36 were decreased (P<0.05), whereas type A scavenger receptor (SR-A) remained unchanged. Moreover, foam cell formation induced by oxLDL and oxLDL binding to macrophages was also inhibited by 7PA. In addition, 7PA increased (P<0.05) expression and protein levels of ATP-binding cassette transporter A1 (ABCA1), which facilitates cholesterol efflux and reduces cholesterol accumulation in macrophages. In summary, the present study demonstrates that certain phenolic acids are potential in vivo atheroprotective compounds following BB consumption in the rodent model. Because BB contain many phytochemicals, other as yet unidentified bioactive compounds may also be important in preventing atherosclerosis in this model and, possibly, in humans.     

Pre- and post-mortem use of grape seed extract in dark poultry meat to inhibit development of thiobarbituric acid reactive substances

Diets containing grape seed extract (GSE)-control, GSE [low GSE, low GSE + methionine, high GSE, and high GSE + methionine], or alpha-tocopherol-were fed to broiler chicks to estimate the antioxidative activity of GSE in processed meat. GSE was detrimental to the growth of chicks, and methionine did not reverse the detrimental effect. GSE with 85.4 g of gallic acid equiv/100 g (GAE 85.4) was added to ground dark turkey meat to obtain treatments with no GSE, 1.0% GSE, and 2.0% GSE and then processed as unsalted or salted and unheated or heated. Processed treatments were analyzed for thiobarbituric acid reactive substances (TBARS) and percent expressible moisture (%EM). GSE at 1.0 and 2.0% decreased TBARS values nearly 10-fold as compared to the control. GSE (1.0%) had a %EM value significantly greater than that of the control. GAE 85.4 decreased TBARS values more than GAE 88.9.     

Relation between solubility and surface hydrophobicity as an indicator of modifications during preparation processes of commercial and laboratory-prepared soy protein isolates

Because water solubility is the main hydration property of proteins, solubility values of commercial and laboratory soy protein isolates, prepared under different conditions, were comparatively analyzed. In contrast, the surface hydrophobicity manifested by proteins is a physicochemical property that determines, to a great extent, the tendency of protein molecules to aggregate and so to lose solubility. On these grounds, the solubility of isolates was analyzed as a function of the surface hydrophobicity of their proteins, and, as a result, three well-defined groups of laboratory isolates were identified: (A) native, (B) partially or totally denatured with high solubility and surface hydrophobicity, and (C) totally denatured with low solubility and surface hydrophobicity. Commercial isolates could not be included in any of these groups; they were grouped as (A') partially native and (C') totally denatured. Solubility values in these two groups were similar to those of group C, but the surface hydrophobicity levels were much lower. The different processes leading to the groups mentioned above are discussed, along with the way the soy proteins are influenced by the specific preparation conditions, namely, protein concentration, chemical or thermal treatments, presence of salts, drying, and phospholipid addition, among others.     

Identification of benzethonium chloride in commercial grapefruit seed extracts.

Commercial grapefruit seed extracts (GSE) were extracted with chloroform. The solvent was evaporated, and the resulting solid was subsequently analyzed by high-performance liquid chromatography, electrospray ionization mass spectrometry, nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis (by proton-induced X-ray emission [PIXE] analysis). The main constituent was identified as benzethonium chloride, a synthetic antimicrobial agent commonly used in cosmetics and other topical applications. This compound comprised 8.03% (n = 2) of the liquid GSE sample. Higher amounts of benzethonium chloride were found in powder GSE samples.     

Farm and operator characteristics affecting adoption of precision agriculture in Denmark and Germany

Precision Agriculture (PA) has been advocated as a promising technology and management philosophy that provides multidimensional benefits for producers and consumers while being environmentally friendly. In Europe, private stakeholders (farm advisors, farm equipment producers, decision support providers, farmers) and research institutions have been trying to develop, test and demonstrate adoption of precision agriculture solutions with governments financing big projects in these areas. Despite these efforts, adoption is still lagging behind expectations.

Whether farmers adopt PA or not is likely to be influenced by several factors. This study intends to identify the main socio-economic determinants of adoption of precision agriculture in Denmark and Germany employing a binary logit model on a cross-section survey data. The results show that farm size, farmer age and demonstration and networking events like attending workshops and exhibitions significantly influence farmers’ adoption decision.     

Identification of metabolites of [1,2,3-(13)C]Propargyl alcohol in mouse urine by (13)C NMR and mass spectrometry and comparison to rat

Species differences in the metabolism of acetylenic compounds commonly used in the formulation of pharmaceuticals and pesticides have not been investigated. To better understand the in vivo reactivity of this bond, the metabolism of propargyl alcohol (PA), 2-propyn-1-ol, was examined in rats and mice. An earlier study (Banijamali, A. R.; Xu, Y.; Strunk, R. J.; Gay, M. H.; Ellis, M. C.; Putterman, G. J. J. Agric. Food Chem. 1999, 47, 1717-1729) in rats revealed that PA undergoes extensive metabolism primarily via glutathione conjugation. The current research describes the metabolism of PA in CD-1 mice and compares results for the mice to those obtained for rats. [1,2,3-(13)C;2,3-(14)C]PA was administered orally to the mice. Approximately 60% of the dose was excreted in urine by 96 h. Metabolites were identified, directly, in whole urine by 1- and 2-D (13)C NMR and HPLC/MS and by comparison with the available reference compounds. The proposed metabolic pathway involves glucuronide conjugation of PA to form 2-propyn-1-ol-glucuronide as well as oxidation of PA to the proposed intermediate 2-propynal. The aldehyde undergoes conjugation with glutathione followed by further metabolism to yield as final products 3,3-bis[(2-acetylamino-2-carboxyethyl)thio]-1-propanol, 3-[(2-acetylamino-2-carboxyethyl)thio]-3-[(2-amino-2-carboxyethyl)thi o]-1-propanol, 3,3-bis[(2-amino-2-carboxyethyl)thio]-1-propanol, 3-[(2-amino-2-carboxyethyl)thio]-2-propenoic acid, and 3-[(2-formylamino-2-carboxyethyl)thio]-2-propenoic acid. A small portion of 2-propynal is also oxidized to result in the excretion of 2-propynoic acid. On the basis of urinary metabolite data, qualitative and quantitative differences are noted between rats and mice in the formation of the glucuronide conjugate of PA and in the formation of 2-propynoic acid and metabolites derived from glutathione. These metabolites represent further variation on glutathione metabolism following its addition to the carbon-carbon triple bond compared to those described for the rat.     

Effect of bioactive dietary polyphenols on zinc transport across the intestinal Caco-2 cell monolayers

Polyphenolic compounds are known to possess many beneficial health effects, including the antioxidative activities of scavenging reactive oxygen species and chelating metals, such as iron and zinc. Tea and red wine are thought to be important sources of these compounds. However, some polyphenolic compounds can also reduce the absorption of iron, and possibly other trace metals, when included in a diet. There is very little information on the effect of dietary polyphenolic compounds on the status of trace elements other than iron. The effects of epigallocatechin-3-gallate (EGCG), green tea extract (GT), and grape seed extract (GSE) on the absorption of (65)Zn were examined and compared with their effects on (55)Fe absorption in human intestinal Caco-2 cells grown on microporous membrane inserts. The levels of EGCG, GT, and GSE used in this study were within physiological ranges and did not affect the integrity of the Caco-2 cell monolayers. GSE significantly (P < 0.05) reduced zinc transport across the cell monolayer, and the decreased zinc transport was associated with a reduction in apical zinc uptake. However, EGCG and GT did not alter zinc absorption. In contrast, the polyphenolic compounds in EGCG, GT, and GSE almost completely blocked transepithelial iron transport across the cell monolayer. The effect of GSE on zinc absorption was very different from that on iron absorption. Whereas GSE decreased zinc absorption by reducing apical zinc uptake, the polyphenolic compounds inhibited iron absorption by enhancing apical iron uptake. GSE inhibited zinc absorption similarly to that observed for phytate. Phytate significantly (P < 0.05) decreased transepithelial zinc transport by reducing apical zinc uptake. The inhibition of zinc absorption may be due to the presence of procyanidins in GSE, which bind zinc with high affinity and block the transport of zinc across the apical membrane of enterocytes. Further research on the absorption of zinc as zinc-polyphenol complexes and free zinc should provide further insight into the process of dietary zinc absorption in the presence of GSE and other bioactive dietary polyphenols. The present study suggests that some individuals should consider their zinc status if they regularly consume procyanidin-containing foods in their diet. However, further studies, especially in vivo studies, are needed to confirm these results.     

An assay to estimate tannins added to postmortem Turkey meat

A method for quantification of tannins in wine was adapted to determine tannins added to turkey meat. Standard curves containing varying amounts of GSE [0, 0.5, 1.0, 1.5, 2.0, 2.5, and 5.0%, (w/w)] as a source of tannins were developed. The R(2) value of the mean standard curve was 0.9992. The overall percent recovery of GSE in meat was determined to be 54.78%. Results showed that estimation of GSE in four out of five of the spiked samples was less than or equal to 10%. It is unclear as to why spiked samples at 0.048 mg of GSE were always underestimated (25.0%). Overall, the method seems applicable for estimation of tannins in poultry meat and is probably applicable to estimation of tannins in other meat products.     

Globulin Expression in Grain of Australian Hard Wheat Cultivars Is Affected by Growth Environment

Our aim was to study changes in wheat proteomes across different growth locations as the first step in linking protein composition with functional changes in grains produced with commercial production systems. Soluble and insoluble proteins were extracted sequentially from grain of three commercial wheat cultivars grown at four locations in New South Wales, Australia, during a single season. Bands were separated with SDS‐PAGE and identified by peptide mass fingerprinting. Quantitative changes in the electrophoretic patterns were observed mainly in the insoluble polypeptides of molecular mass 40,000–70,000 for all three cultivars grown at two of the four locations. These proteins were identified as mainly globulin and serpin isoforms, as well as triticin. Other proteins with changed expression included disease‐resistance proteins, class III peroxidase, starch branching enzyme I, β‐amylase, and storage proteins. Two‐dimensional electrophoretic analysis was performed on two of the same wheat cultivars grown at one of the locations during two consecutive seasons. Protein spots that varied between seasons consisted of globulin and serpin isoforms, triticin, HMW glutenin, γ‐gliadin, starch branching enzyme IIb, and α‐amylase. The implications of the upregulation of globulin and triticin on whole meal flour quality, through their participation in polymerization of the gluten network, are considered.     

Kinetics of thermal modifications in a grape seed extract

The thermal modification kinetics of a commercial grape seed extract (GSE) was investigated. A GSE was exposed to 60, 90, and 120 °C for 5, 10, 15, 30, 45, and 60 min. The antioxidant activity (AA) and the absorbance at 420 nm (A(420)) were measured. (+)-Catechin, (-)-epicatechin, procyanidins B1 and B2, and gallic acid were identified and measured. After the thermal treatments, the AA did not show a significant difference (p > 0.05) and both procyanidins and gallic acid increased as well as A(420). (+)-Catechin and (-)-epicatechin decreased. To obtain the activation energy (E(a)) of the changes, a modified Weibull and a combined zero- and first-order model were compared, both followed by the Arrhenius equation. The Weibull model was more accurate. The E(a) values for browning and (+)-catechin, (-)-epicatechin, gallic acid, and procyanidins B1 and B2 were 170, 286, 42, 102, 249, and 95 kJ/mol, respectively. The results were valid at a confident level of 95%.     

Grape seed polyphenols protect cardiac cells from apoptosis via induction of endogenous antioxidant enzymes

Grape seed extract (GSE) has been reported to exert protective effects on various forms of cardiac disorders. The cardiovascular protective effects of GSE are believed to be ascribed to its antioxidative properties. A series of studies have demonstrated that polyphenols are instrumental for the antioxidative properties of GSE. This study was undertaken to investigate whether two major polyphenols isolated from GSE (catechin and proanthocyanidin B4) could increase the endogenous antioxidant enzymes in cardiomyocytes, and whether such increased cellular defenses could provide protection against oxidative cardiac cell injury. Incubation of cardiac H9C2 cells with micromolar concentrations of catechin or proanthocyanidin B4 resulted in a significant induction of cellular antioxidant enzymes in a concentration-dependent fashion. Furthermore, catechine or proanthocyanidin B4 pretreatment led to a marked reduction in xanthine oxidase (XO)/xanthine-induced intracellular reactive oxygen species (ROS) accumulation and cardiac cell apoptosis. These results indicated that grape seed polyphenols (GSP) could protect against cardiac cell apoptosis via the induction of endogenous antioxidant enzymes. This may be an important mechanism underlying the protective effects of GSE observed with various forms of cardiovascular disorders.     

Quantification of phosphatidic acid in foodstuffs using a thin-layer-chromatography-imaging technique

Apical application of lysophosphatidic acid (LPA), a growth-factor-like phospholipid, was shown to prevent or restore gastrointestinal (GI) disorders, such as diarrhea and stomach ulcer, in experimental animals. Because LPA is formed from phosphatidic acid (PA) by the activity of digestive phospholipase A(2), PA is a potential component for dietary treatment of such GI disorders. Here, we quantified PA contained in 38 foodstuffs and 3 herbs by a thin-layer-chromatography-imaging technique. Vegetables belonging to Brassicaceae, such as cabbage leaves (700 nmol/g of wet weight) and Japanese radish leaves (570 nmol/g), contained higher amounts of PA than other foodstuffs. Amounts of PA in fruits, cereals, and starchy root vegetables were below 300 nmol/g. Animal foodstuffs contained low amounts of PA (<60 nmol/g). Interestingly, leaves of Mallotus japonicas, a Japanese edible herb used for treatment of stomach ulcer, had the highest PA (1410 nmol/g) among those examined. The data shown here will be useful for the development of dietary treatment for a damaged GI tract.     

Effect of addition of commercial grape seed tannins on phenolic composition, chromatic characteristics, and antioxidant activity of red wine

The effect of addition of grape seed tannins on the phenolic composition, chromatic characteristics, and antioxidant activity of red wine was studied. Two highly pure commercial grape seed tannins (GSE100 and GSE300) were selected, and their phenolic compositions were determined. Two types of red wines were made with Castela?o/Tinta Miu?da (3/2, w/w) grapevine varieties by fermentation on skin using two different maceration times, which correspond to the wines rich and poor in polyphenols, respectively. Each of these wines was used for experimentation with the addition of GSE100 and GSE300 before and immediately after alcoholic fermentation. Phenolic composition, chromatic characteristics, and antioxidant activity of the finished red wines were analyzed by HPLC-DAD, CIElab 76 convention, and DPPH radical test, respectively. The results showed that the addition of grape seed tannins had obvious effects of increasing color intensity and antioxidant activity only in the wines poor in polyphenols. Although GSE300 contained much higher amounts of di- and trimer procyanidins and a lower amount of polymeric proanthocyanidins, it provided effects of increasing the color intensity and antioxidant activity of the wines poor in polyphenols similar to those of GSE100. Furthermore, GSE100 released more gallic acid to wines than GSE300, although no gallic acid was detected in GSE100. Tannins added after alcoholic fermentation had a better effect on phenolic composition of red wine than tannins added before alcoholic fermentation.     

Bioavailability and tissue distribution of sesamol in rat

Sesamol, generally regarded as the main antioxidative component in sesame oil, can be generated from sesamolin by roasting sesame seed or bleaching sesame oil. This paper reports the bioavailability of sesamol in Sprague-Dawley (SD) rats. Biological fluid was sampled following a dose of sesamol of 50 mg/kg by gastric gavage (p.o.) or by intravenous injection. The pharmacokinetic data of sesamol were calculated by noncompartmental model. The tissue distribution of sesamol (p.o., 100 mg/kg) in SD rats was also investigated. The concentration changes of sesamol were determined in various tissues and plasma within a 24 h period after oral administration of sesamol. The results showed that the oral bioavailability of sesamol was 35.5 +/- 8.5%. Sesamol was found to be able to penetrate the blood-brain barrier and go through hepatobiliary excretion. Sesamol conjugated metabolites were widely distributed in SD rat tissues, with the highest concentrations in the liver and kidneys and the lowest in the brain. It is postulated that sesamol is incorporated into the liver first and then transported to the other tissues (lung, kidneys, and brain). The major metabolites of sesamol distributed in the lung and kidney were glucuronide and sulfate.     

Protection by petaslignolide A, a major neuroprotective compound in the butanol extract of Petasites japonicus leaves, against oxidative damage in the brains of mice challenged with kainic acid

The neuroprotective effect of petaslignolide A (PA), a furfuran lignan isolated from butanol fraction of Petasites japonicus (Sieb. et Zucc.) Maxim. (Compositae) leaves, on the oxidative damage in the brain of mice challenged with kainic acid was examined using behavioral signs and biochemical parameters of oxidative stress. PA (40 mg/kg) was administered to ICR male mice through a gavage for 4 days consecutively, and on the final day, kainic acid (50 mg/kg) was administered intraperitoneally. During the 4-day treatment with PA, the body weight gain was not significantly different from that of vehicle-treated control animals. PA (40 mg/kg) alleviated the behavioral signs of kainic acid neurotoxicity and reduced the mortality (50%) by kainic acid to 12.5%. Moreover, the administration of PA restored the levels of glutathione and thiobarbituric acid-reactive substances as well as GSH-peroxidase activity in the brains of mice administered kainic acid to control levels (P < 0.05). In comparison, PA (40 mg/kg) was approximately comparable to the butanol fraction (200 mg/kg) of P. japonicus extract in reducing kainic acid neurotoxicity. On the basis of these results, PA is suggested to be a major neuroprotective agent primarily responsible for the protective action of the butanol fraction of P. japonicus extract against kainic acid-induced neurotoxicity in the brains of mice.     

Endogenous formation of N'-nitrosonornicotine in F344 rats in the presence of some antioxidants and grape seed extract

N'-Nitrosonornicotine (NNN) is one of the most abundant strong carcinogens in unburned tobacco and cigarette smoke and is classified by the International Agency for Research on Cancer as carcinogenic to humans. Human exposure to NNN mainly occurs upon use of tobacco products. It is also possible that additional amounts of NNN are formed endogenously. The goal of this study was to evaluate the inhibitory effect of some antioxidants, including ascorbic acid and grape seed extract (GSE), on endogenous NNN formation in rats treated with nornicotine and sodium nitrite by gavage twice daily for 3 days. The study included four groups of rats: (1) negative control group A, to which no chemical was administered; (2) negative control group B, treated with nornicotine alone (2.5 micromol per gavage); (3) positive control group, to which both nornicotine (2.5 micromol per gavage) and sodium nitrite (7.5 micromol per gavage) were administered; and (4) rats treated with nornicotine (2.5 micromol per gavage), inhibitor (7.5 or 37.5 micromol per gavage), and sodium nitrite (7.5 micromol per gavage). The mean (+/-SD) total amount of NNN in the 3-day urine of rats treated with both nornicotine and sodium nitrite was 4.78 +/- 2.88 nmol. The order of inhibition of endogenous NNN formation in rats at the molar ratio [nitrite]:[inhibitor] 1:5 was as follows: ascorbic acid (91%) > dihydroxyfumaric acid (86%) approximately catechin (85%) > resveratrol (no inhibition). Treatment of rats with grape seed extract did not produce statistically significant inhibition of endogenous nornicotine nitrosation. This is the first study that demonstrates endogenous NNN formation in rats treated with nornicotine and sodium nitrite and effective inhibition of this process by ascorbic acid, dixydroxyfumaric acid, and catechin.     

Evaluation of the NO scavenging activity of procyanidin in grape seed by use of the TMA-PTIO/NOC 7 ESR system

The nitrogen monoxide (NO) scavenging activity of grape seed extract (GSE) was studied in the TMA-PTIO/NOC 7 system. The procyanidin-rich (>95%) GSE showed strong NO scavenging activity in the system. The activity was found to depend on the condensation rate of cyanidin when synthetic oligomers were tested. Investigation of the NO scavenging activities of other polyphenols (catechin, epicatechin, epigallocatechin, and epigallocatechin gallate) in the TMA-PTIO/NOC 7 system revealed that gallocatechin, epigallocatechin, and epigallocatechin gallate exhibited strong activities. From the results, it was suggested that the high condensation rate of and the gallate ester moiety in procyanidin in GSE may play an important role in the NO scavenging activity. The mechanism of the NO scavenging activity of phenolic compounds such as GSE is speculated to be as follows: NO reacts with phenolic compounds directly to generate phenoxy radicals.     

Identification of protein degradation during post-mortem storage of pig meat

Eighteen proteins and peptides that were found to change post-mortem in Longissimus dorsi from pig muscle were identified by the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The 18 peptides originate from 9 different proteins including the 3 structural proteins (actin, myosin heavy chain, and troponin T) and the 6 metabolic proteins glycogen phosphorylase, creatine kinase, phosphopyruvate hydratase, myokinase, pyruvate kinase, and dihydrolipoamide succinyltransferase. The molecular weight and estimated sequence length of the identified spots show that these fragments result from proteolytic activity in meat. Identification of the parent proteins and the enhanced post-mortem appearance of the degradation products make these specific peptides good candidates for meat quality markers, and further studies of these specific fragments will lead to a better understanding of the proteolytic activities involved in the post-mortem conversion of muscle to meat.