Effects of grape cell culture extracts on human topoisomerase II catalytic activity and characterization of active fractions

Grape and its cell culture extracts are rich in flavonoids and stilbenes that are biologically active. The objective of this study was to evaluate possible inhibitory effects of grape (a Vitis hybrid Bailey Alicant A) cell culture extract and subfractions on human DNA topoisomerase II catalytic activity and to characterize constituents in the most potent fractions. At 5 microg/mL, grape cell crude extract and Toyopearl (TP) fractions 2-6 provided significantly greater inhibition of topoisomerase II catalytic activity than quercetin, a chemopreventive agent previously known as a topoisomerase catalytic inhibitor. The most potent topoisomerase II catalytic inhibitors from grape cell culture extracts in descending order of potency were TP fractions 4 and 6 (IC(50) = 0.28-0.29 microg/mL), TP-3 (IC(50) = 0.74 microg/mL), and crude extract (IC(50) = 1.02 microg/mL); each was significantly more potent than resveratrol (IC(50) = 18.0 microg/mL), another well-known chemopreventive topoisomerase II catalytic inhibitor. Using both high-performance liquid chromatography and liquid chromatography electrospray ionization mass spectrometry, constituents in TP-4 and TP-6 were characterized. These constituents included cyanidin-3,5-diglucoside, malvidin-3-acetylglucoside, peonidin-3-coumaryl-5-diglucoside, procyanidin B(1), procyanidin B(2), procyanidin B(5), procyanidin dimer digallate, procyanidin C(1), myricetin, and rutin, none of which have been previously characterized from grape cell cultures. The significant potency especially of TP-4 and TP-6 from grape cell cultures suggests that these fractions may have potential as chemopreventive agents.     

Grape seed proanthocyanidins prevent plasma postprandial oxidative stress in humans

Postprandial hyperlipemia is a well-defined risk factor for atherosclerosis. A reasonable contributing mechanism could involve the postprandial increase of plasma lipid hydroperoxides (LPO) affecting the oxidant/antioxidant balance and increasing the susceptibility of LDL to oxidation. Wine has been shown to prevent both these events. The present study was designed to investigate the effect of supplementing a meal with grape seed proanthocyanidins (the main phenolic antioxidant of red wine) on plasma postprandial oxidative stress. In two different sessions, 8 healthy volunteers consumed the same test meal rich in oxidized and oxidizable lipids without (control) or with 300 mg of a proanthocyanidin-rich grape seeds extract (GSE). Lipid hydroperoxide concentration, antioxidant status, and LDL resistance to oxidative modification were measured in postprandial plasma. The content of LPO in chylomicrons was 1.5-fold higher after the control meal than after the GSE-supplemented meal. Plasma LPO increased only after consumption of the control meal. The plasma antioxidant capacity increased in the postprandial phase only following the GSE supplemented meal. LDL isolated 3 h after the control meal tended to be more susceptible to oxidative modification (but the difference did not reach statistical significance). An opposite trend was observed following the GSE supplemented meal. In conclusion, the supplementation of a meal with GSE minimizes the postprandial oxidative stress by decreasing the oxidants and increasing the antioxidant levels in plasma, and, as a consequence, enhancing the resistance to oxidative modification of LDL.     

Chemical characterization of red wine grape (Vitis vinifera and Vitis interspecific hybrids) and pomace phenolic extracts and their biological activity against Streptococcus mutans

Grapes are rich sources of potentially bioactive polyphenols. However, the phenolic content is variable depending on grape variety, and may be modified during vinification. In this study, we examined the chemical composition and biological activity of phenolic extracts prepared from several red wine grape varieties and their fermented byproduct of winemaking (pomace) on some of the virulence properties of Streptococcus mutans a well-known dental pathogen. Grape phenolic extracts were obtained from Vitis vinifera varieties Cabernet Franc and Pinot Noir and Vitis interspecific hybrid varieties Baco Noir and Noiret. The anthocyanins and flavan-3-ols content were highly variable depending on grape variety and type of extract (whole fruit vs fermented pomace). Nevertheless, all grape phenolic extracts remarkably inhibited glucosyltransferases B and C (70-85% inhibition) at concentrations as low as 62.5 microg/mL (P < 0.01). Furthermore, the glycolytic pH-drop by S. mutans cells was inhibited by the grape extracts without affecting the bacterial viability; an effect that can be attributed to partial inhibition of F-ATPase activity (30-65% inhibition at 125 microg/mL; P < 0.01). The biological activity of fermented pomace was either as effective as or significantly better than whole fruit grape extracts. The results showed that grape phenolic extracts, especially from pomace, are highly effective against specific virulence traits of S. mutans despite major differences in their phenolic content.     

Insulin secretion and cyclooxygenase enzyme inhibition by cabernet sauvignon grape skin compounds

Bioassay-guided isolation and purification of hexane and ethyl acetate extracts of Cabernet Sauvignon grape skin yielded nine compounds (1-9), which were identified as beta-sitosterol-6'-linolenoyl-3-O-beta-D-glucopyranoside (1), beta-sitosterol (2), beta-sitosterol-3-O-beta-D-glucoside (3), oleanolic acid (4), oleanolic aldehyde (5), resveratrol (6), (+)-epsilon-viniferin (7), (-)-catechin (8), and 1-triacontanol (9). The structures of these compounds were established by spectroscopic methods. The compounds were assayed for insulin production using an INS-1 cell assay. In a dose-response study, compound 4 stimulated insulin production of INS-1 cells by 20.23, 87.97, 1.13, and 6.38 ng of insulin/mg of protein at 6.25, 12.5, 25, and 50 microg/mL, respectively. This trend was similar to the dose-dependent insulin production of INS-1 cells by glucose. Compound 5 also showed a dose-dependent insulin production in this assay. The isolated compounds were also assayed for cyclooxygenase-1 and -2 (COX) enzyme inhibitory activities. At 100 microg/mL, compounds 2, 3, and 4 inhibited the COX-2 enzyme by 11, 12, and 10%, respectively, but did not show activities on the COX-1 enzyme. Compounds 6, 7, and 8 at 100 microg/mL inhibited the COX-1 enzyme by 98, 99, and 98%, respectively, and the COX-2 enzyme by 0, 47, and 72%, respectively. This is the first report of beta-sitosterol-6'-linolenoyl-3-O-beta-D-glucopyranoside (1) from grape skin and insulin secretion activities of compounds 4 and 5.     

3-(4'-hydroxyl-3',5'-dimethoxyphenyl)propionic acid, an active principle of kimchi, inhibits development of atherosclerosis in rabbits

The effects of 3-(4'-hydroxyl-3',5'-dimethoxyphenyl)propionic acid (HDMPPA) originating from Korean cabbage kimchi were investigated, showing an antioxidant effect on the prevention of atherosclerosis in hypercholesterolemic rabbits. Twenty-one 3-month-old rabbits were fed an atherogenic diet containing 0.5% (w/w) cholesterol and 10% (w/w) coconut oil, whereas another two groups were given an atherogenic diet with intravenous injection of either HDMPPA or simvastatin (0.33 mg/kg/day) for 4 weeks. HDMPPA inhibited the oxidative modification of low-density lipoprotein (IC 50 = 1.4 microg/mL) and increased 2,2'-diphenyl-1-picrylhydrazyl radical scavenging activity (IC 50 = 0.78 microg/mL) in a dose-dependent manner. In hypercholesterolemic rabbits, the thickness of intima of aorta of the HDMPPA group was significantly reduced (control versus HDMPPA, 42%; simvastatin, 38%) without a plasma cholesterol-lowering effect. Thiobarbituric acid reactive substance formation in the plasma of the HDMPPA group was significantly decreased compared to that of the control group. Furthermore, the generation of vascular reactive oxygen species in HDMPPA group was suppressed as the cyclooxygenase-2 protein level decreased. These findings suggest that HDMPPA prevents the development of aortic atherosclerosis in high-cholesterol-fed rabbits. The antiatherosclerotic effect of HDMPPA may be due to an antioxidative effect at a low dose without cholesterol-lowering effects.     

Estrogenic effects of extracts from cabbage, fermented cabbage, and acidified brussels sprouts on growth and gene expression of estrogen-dependent human breast cancer (MCF-7) cells

Cruciferous vegetable extracts from freeze-dried cabbage (FDC), freeze-dried fermented cabbage (FDS), and acidified Brussels sprouts (ABS) were prepared by exhaustive extraction with ethyl acetate. Estrogenic and antiestrogenic effects of these extracts were analyzed. To identify whether the extracts are potential estrogen receptor (ER) ligands that can act as agonists or antagonists, the binding affinity of extracts for the ER was measured using a competitive radiometric binding assay. The extracts bound with low affinity to the ER, and the relative binding affinity is estradiol > FDS > FDC > ABS. These extracts were evaluated for their estrogenic and antiestrogenic activities in estrogen-dependent human breast cancer (MCF-7) cells using as endpoints proliferation and induction of estrogen-responsive pS2 gene expression, which was analyzed using Northern blot assay. At low concentrations (5-25 ng/mL) all of the extracts reduced 1 nM estradiol-induced MCF-7 cell proliferation. Extracts at 25 ng/mL also inhibited estradiol-induced pS2 mRNA expression. At higher extract concentrations (50 ng/mL-25 microg/mL), however, increased proliferation in MCF-7 cells was observed. Similarly, expression of the pS2 gene was induced by higher extract concentrations (0.25-25 microg/mL). The pure estrogen antagonist, ICI 182,780, suppressed the cell proliferation induced by the extracts as well as by estradiol and also the induction of pS2 expression by the extracts. The ER subtype-selective activities of FDC and FDS were analyzed using a transfection assay in human endometrial adenocarcinoma (HEC-1) cells. FDS acted as an ERalpha-selective agonist while FDC fully activated both ER-alpha and ER-beta. Growth of the ER-negative MDA-231 cells was not affected by the extracts or by estradiol. This study demonstrates that cruciferous vegetable extracts act bifunctionally, like an antiestrogen at low concentrations and an estrogen agonist at high concentrations.     

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.     

Phycobiliprotein C-phycocyanin from Spirulina platensis is powerfully responsible for reducing oxidative stress and NADPH oxidase expression induced by an atherogenic diet in hamsters

The effects of spirulina and its chromophore phycocyanin, both without bound Se or selenium-enriched, were studied on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anions, and NAD(P)H oxidase expression in hamsters. Forty hamsters were divided into 5 groups of 8 and fed an atherogenic diet for 12 weeks. They received by gavage either 7.14 mL/(kg day) phycocyanin (PC), Se-rich phycocyanin (SePC), spirulina (SP) or Se-rich spirulina (SeSP) in water, or water as control. SeSP and SePC supplied 0.4 microg of Se per 100 g body weight. Plasma cholesterol and non-HDL cholesterol concentrations were lower in group consuming SePC. HDL-cholesterol was never affected. SePC significantly increased plasma antioxidant capacity by 42% compared with controls. A sparing effect in liver glutathione peroxidase (87% on average) and superoxide dismutase (56% on average) activity was observed for all the groups compared to controls. Aortic fatty streak area was significantly reduced in the experimental groups, especially by PC (82%) and SePC (85%). Cardiac production of superoxide anion significantly decreased by approximately 46-76% in the four experimental groups and especially in SePC group (76%). The expression of p22phox subunit of NAD(P)H oxidase decreased by 34% after consumption of SePC. The results indicate that chronic consumption of Se-rich spirulina phycocyanin powerfully prevents the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and at a lesser extent improving the serum lipid profile.     

Cytogenetic effects of grape extracts (Vitis vinifera) and polyphenols on mitomycin C-induced sister chromatid exchanges (SCEs) in human blood lymphocytes

In the present study, the effects of extracts and polyphenol-rich fractions as well as monomer polyphenols identified in them, from both red and white grapes, on mitomycin C (MMC) induced sister chromatid exchanges (SCEs) in human peripheral blood lymphocytes were investigated. The grape extracts and two of the three polyphenol-rich fractions promoted MMC-induced SCEs at concentrations from 75 to 300 microg/mL. However, none of the extracts or fractions alone induced SCEs. Thus, these results suggest caution especially with regard to the use of grape extracts as dietary supplements. On the other hand, the fact that these extracts were not genotoxic alone may indicate a selective activity against genetically damaged cells. This is the first study regarding the clastogenic effects of grape extracts in human cells. Moreover, from the tested polyphenols, caffeic acid, gallic acid, and rutin hydrate enhanced MMC-induced clastogenicity, whereas ferulic acid, protocatechuic acid, (+)-catechin, (-)-epicatechin, and trans-resveratrol had no effect at concentrations between 5 and 100 microM. The differences in the chemical structures of the tested polyphenols may account for their differential effects on MMC clastogenicity.     

Stability and emulsifying capacity of biosurfactants obtained from lignocellulosic sources using Lactobacillus pentosus

Lactobacillus pentosus grown on sugars from agricultural residues produces biosurfactants with emulsifying properties that could facilitate the bioremediation of hydrocarbon contaminated sites. The biosurfactans obtained after growing L. pentosus cells on distilled grape marc hydrolyzates gave values of relative emulsion volume (EV) close to 50%, being stable after 72 h when gasoline or kerosene were employed. These EV values were higher than those achieved using commercial surfactin (14.1% for gasoline and 27.2% for kerosene). Moreover, assays carried out with kerosene showed that L. pentosus produced biosurfactants from distilled grape marc hydrolyzates with the highest stabilizing capacity value (ES) to maintain the emulsion (99%) followed by biosurfactants produced from hazelnut shell hydrolyzates (97%). These data are comparable with those obtained using sodium dodecyl sulfate, SDS (87.7%), whereas surfactin only gave an ES value of 65.4%. Consequently, this work shows that utilization of low-cost feedstock agricultural residues as substrates for producing biosurfactants/bioemulsifiers is possible thus removing obstacles for the wide-scale industrial application of biosurfactants/bioemulsifiers.     

Grape-seed procyanidins act as antiinflammatory agents in endotoxin-stimulated RAW 264.7 macrophages by inhibiting NFkB signaling pathway

Procyanindin extract (PE) is a mixture of polyphenols, mainly procyanidins, obtained from grape seed with putative antiinflammatory activity. We evaluated the PE effect on RAW 264.7 macrophages stimulated with lipopolysaccharide plus interferon-gamma that show a rapid enhanced production of prostaglandin E2 (PGE2) and nitric oxide (NO). Our results demonstrated that PE significantly inhibited the overproduction of NO, dose and time dependently. PE caused a marked inhibition of PGE2 synthesis when administered during activation. Moreover, PE pretreatment diminished iNOS mRNA and protein amount dose dependently (10-65 microg/mL). PE (65 microg/mL) pretreatment inhibited NFkappaB (p65) translocation to nucleus by nearly 40%. Trimeric and longer oligomeric-rich procyanidin fractions from PE (5-30 microg/mL) inhibited iNOS expression but not the monomeric forms catechin and epicatechin. Thus, we show that the degree of polymerization is important in determining procyanidin effects. PE was considerably a more effective inhibitor of NO biosynthesis (IC50 = 50 microg/mL) in comparison to other antiinflammatories, such as aspirin (3 mM), indomethacin (20 microM), and dexamethasone (9 nM). In conclusion, PE modulates inflammatory response in activated macrophages by the inhibition of NO and PGE2 production, suppression of iNOS expression, and NFkB translocation. These results demonstrate an immunomodulatory role of grape seed procyanidins and thus a potential health-benefit in inflammatory conditions that exert an overproduction of NO and PGE2.     

Novel biological properties of Oenothera paradoxa defatted seed extracts: effects on metallopeptidase activity

In this study, for the first time, we used the in vitro metallopeptidase model for the identification of a potential novel activity of defatted evening primrose seed extracts. Prepared extracts of different polarity (aqueous, 60% ethanolic, isopropanolic, and 30% isopropanolic) at concentrations of 1.5-100 microg/mL exhibited a significant and dose dependent inhibition of three tested enzymes. The 50% inhibition of enzymes activity showed that aminopeptidase N (APN) was the enzyme affected to the greatest extent with IC50 at the level of 2.8 microg/mL and 2.9 microg/mL for aqueous and 30% isopropanolic extracts, respectively. The activity of neutral endopeptidase (NEP) was quite strongly inhibited by the extracts as well. The HPLC-DAD analysis and bioguided fractionation led to the identification of four active compounds: (-)-epicatechin gallate, proanthocyanidin B3, oenothein B, and penta-O-galloyl-beta-D-glucose (PGG). Oenothein B has been shown previously to inhibit metallopeptidases. The three other compounds are known to inhibit angiotensin-converting enzyme (ACE), but they have not been previously reported to inhibit the NEP and APN activity. PGG and procyanidins with different degrees of polymerization, as the dominating compounds in O. paradoxa seeds, seemed to play a role in the crude extract activity.     

Antioxidative activity of volatile extracts isolated from Angelica tenuissimae roots, peppermint leaves, pine needles, and sweet flag leaves

Volatile extracts were isolated from dried medicinal plants [Angelica tenuissimae roots (AT, Angelica tenuissima Nakai), peppermint leaves (PL, Mentha arvensis L.), pine needles (PN, Pinus sylvestris L.), and sweet flag leaves (SF, Acorus gramineus Rhizoma)] using steam distillation under reduced pressure, followed by continuous liquid-liquid extraction (DRP-LLE). The extracts were then analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major volatile constituents of AT, PL, PN, and SF were 3-butylidene-4,5-dihydrophthalide (32 mg/g), menthol (18 mg/g), thunbergol (2.1 mg/g), and cis-asarone (37 mg/g), respectively. The inhibitory activity (%) of the extracts against hexanal oxidation ranged from 33 to 98% at a level of 50 microg/mL. Among the volatile extracts, PL and PN increased cell viabilities by 10 and 24%, respectively, at a dose of 1 microg/mL, compared to that of H2O2-treated brain neuroblastoma cells, SK-N-SH. However, a 20% reduction in the malonaldehyde level, an index for lipid peroxidation, was observed at only 1 microg/mL concentration of PN.     

Suppression of lipopolysaccharide and galactosamine-induced hepatic inflammation by red grape pomace

Grape pomace is generated in the production process of wine and grape juices and is an industrial waste. This study investigated whether an intake of grape pomace was able to suppress chronic inflammation induced by lipopolysaccharide (LPS) and galactosamine (GalN) in vivo. When Sprague-Dawley rats were orally given methanolic extracts from red and white grape pomace, the extracts inhibited the LPS/GalN-evoked activation of nuclear factor-κB (NF-κB) dose-dependently, and red grape pomace exerted a stronger effect than white grape one. Next, rats were fed an AIN93 M-based diet containing 5% red grape pomace for 7 days, followed by the intraperitoneal injection of LPS and GalN. The intake of the red grape pomace-supplemented diet was found to suppress the LPS/GalN-induced activation of NF-κB and expression of inducible nitric oxide synthase and cyclooxygenase-2 proteins. These results suggest that red grape pomace may contain an abundance of effective compound(s) for anti-inflammatory action.     

Study of anticancer activities of muscadine grape phenolics in vitro

Muscadine grapes have unique aroma and flavor characteristics. Although a few studies reported high polyphenols content of muscadine grapes, little research has been conducted to evaluate the phenolic compounds bioactivities in any muscadine grape cultivar. The objective of this study was to evaluate the effect of phenolic compounds in muscadine grapes on cancer cell viability and apoptosis. Four cultivars of muscadine (Carlos, Ison, Noble, and Supreme) were assessed in this study. Phenolic compounds were extracted from muscadine skins and further separated into phenolic acids, tannins, flavonols, and anthocyanins using HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC. Anthocyanin fractions were more than 90% pure. The effect of different fractions on the viability and apoptosis of two colon cancer cell lines (HT-29 and Caco-2) was evaluated. A 50% inhibition of cancer cell population growth for the two cell lines was observed at concentrations of 1-7 mg/mL for crude extracts. The phenolic acid fractions showed a 50% inhibition at the level of 0.5-3 mg/mL. The greatest inhibitory activity was found in the anthocyanin fraction, with a 50% inhibition at concentrations of approximately 200 microg/mL in HT-29 and 100-300 microg/mL in Caco-2. Anthocyanin fractions also resulted in 2-4 times increase in DNA fragmentation, indicating the induction of apoptosis. These findings suggest that polyphenols from muscadine grapes may have anticancer properties.     

A commercial extract of fruits and vegetables, Oxxynea, acts as a powerful antiatherosclerotic supplement in an animal model by reducing cholesterolemia, oxidative stress, and NADPH oxidase expression

The effects of fruit and vegetable extract (Oxxynea) on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anion, and NAD(P)H oxidase expression were studied in an animal model of atherosclerosis. Thirty six hamsters were divided into two groups of 18 and fed an atherogenic diet for 12 weeks. They received by gavage either water or Oxxynea in water at a human dose equivalent of 10 fruits and vegetables per day. Oxxynea lowered plasma cholesterol and non-HDL cholesterol, but not HDL-cholesterol, and increased plasma antioxidant capacity. It also strongly reduced the area of aortic fatty streak deposition by 77%, cardiac production of superoxide anion by 45%, and p22phox subunit of NAD(P)H oxidase expression by 59%. These findings support the view that chronic consumption of antioxidants supplied by fruits and vegetables has potential beneficial effects with respect to the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and improving the serum lipid profile.     

Contamination of grape seed oil with mineral oil paraffins

The contamination of 11 commercial grape seed oils with paraffins of mineral oil origin was analyzed by online-coupled HPLC-HPLC-GC-FID and ranged from 43 to 247 mg kg(-1). The analysis of the marc and seeds indicated that the contamination is primarily from the peels. Since superficial extraction of the seeds with hexane removed most of the mineral paraffins, the contamination of the seeds is largely on the surface, perhaps transferred from the peels during storage of the marc. Mechanical purification of the seeds combined with washing with hexane reduced the contamination of the oil by a factor of about 10. The refining process removed 30% of the mineral paraffins, primarily the more volatile components. Oil obtained from the seeds of fresh grapes, including grapes not having undergone any phytochemical treatment, contained clearly less mineral paraffins (up to 14 mg kg(-1)), and the peels were less contaminated, suggesting an environmental background contamination. To this an additional contamination might be added by a treatment of the grapes used for wine making.     

Cocomposting of Beet Vinasse and Grape Marc In Windrows and Static Pile Systems

Two composts were obtained by cocomposting a concentrated depotassified beet vinasse and grape marc using an aerated static pile and a windrow system. The composting mixtures comprised grape marc (83%) and vinasse (17%) for the aerated static pile system and grape marc (77%), vinasse (20%) and phosphate rock (3%) for the windrow. Changes in temperature followed a similar path for both mixtures, however the thermophilic phase was longer in the aerated static pile (25 days) than in the windrow (10 days). This fact caused differences in both organic matter degradation, weight losses (21% for static pile and 10% for windrow) and gas losses during the process. Nevertheless, the composts obtained by the two systems had a high fertilizer nutrient value (18.2 g kg^?1 N; 3.1 g kg^?1 P; 13.6 g kg^?1 K, C/N 16.1 for compost obtained in static pile and 20.6 g kg^?1 N; 13.7 g kg^?1 P; 13.1 g kg^?1 K; C/N 18 for compost obtained in windrow). A high degree of stability was reached in both composting systems (124 cmol_c kg^?1 CEC for static pile and 153 cmolc kg^?1 CEC for windrow at 80 days of composting). The chemical and physical properties of both vinasse composts suggest their possible use as soil conditioner.     

Radical scavenging and anti-lipoperoxidative activities of Smallanthus sonchifolius leaf extracts

Radical scavenging and anti-lipoperoxidative effects of two organic fractions and two aqueous extracts from the leaves of a neglected Andean crop-yacon (Smallanthus sonchifolius Poepp. & Endl., Asteraceae) were determined using various in vitro models. The extracts' total phenolic content was 10.7-24.6%. They exhibited DPPH (IC50 16.14-33.39 microg/mL) and HO* scavenging activities (4.49-6.51 mg/mL). The extracts did not scavenge phenylglyoxylic ketyl radicals, but they retarded their formation. In the xanthine/xanthine oxidase superoxide radical generating system, the extracts' activities were 26.10-37.67 superoxide dismutase equivalents/mg. As one of the extracts displayed xanthine oxidase inhibitory activity, the effect of the extracts on a nonenzymatically generated superoxide was determined (IC50 7.36-21.01 microg/mL). The extracts inhibited t-butyl hydroperoxide-induced lipoperoxidation of microsomal and mitochondrial membranes (IC50 22.15-465.3 microg/mL). These results make yacon leaves a good candidate for use as a food supplement in the prevention of chronic diseases involving oxidative stress.     

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.