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Objective: We aimed to investigate the effect of Sicyos angulatus (SA) ethanolic extracts as antioxidants and potential treatments for liver disease., Methods: To establish a mouse model of liver injury, C57BL/6 male mice were injected via the caudal vein with a single dose of concanavalin A (Con A, 15 mg kg -1 ). SA extracts were administered once by oral gavage 30 min before Con A injection., Results: In vitro studies showed that SA decreased tert-butyl hydroperoxide (t-BHP)-induced reactive oxygen species (ROS) production. SA administration reduced plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as well as hepatic ROS levels, in a dose-dependent manner. Moreover, SA increased the activities of the hepatic antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner. Furthermore, SA treatment reduced pro-apoptotic protein levels. Con A-mediated cytosolic release of Smac/DIABLO and apoptosis-inducing factor (AIF), which are markers of necrosis, were dramatically decreased in HepG2 cells treated with SA., Conclusion: SA ameliorated liver injury and might be a good strategy for the treatment of liver injury.

Effects of low-dosage electron beam irradiation on antioxidant activities of Navel oranges during storage at a low temperature of 3°C were studied. Oranges were irradiated at dosages of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy and changes in antioxidant compounds and antioxidant activities were investigated. No changes in total phenolic contents or flavonoid contents were observed with an increase in radiation dosage. Also, no differences between non-irradiated and irradiated oranges in DPPH radical scavenging and ABTS radical scavenging activities, FRAP values, and reducing powers were observed. Electron beam irradiation at dosages less than 1 kGy does not affect levels of antioxidant compounds and antioxidant activities of Navel oranges.

Mangostenone F (MF) is a natural xanthone isolated from Garcinia mangostana. However, little is known about the biological activities of MF. This study was designed to investigate the anti-inflammatory effect and underlying molecular mechanisms of MF in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. MF dose-dependently inhibited the production of NO, iNOS, and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in LPS-stimulated RAW264.7 macrophages. Moreover, MF decreased the NF-κB luciferase activity and NF-κB DNA binding capacity in LPS-stimulated RAW264.7 macrophages. Furthermore, MF suppressed the NF-κB activation by inhibiting the degradation of IκBα and nuclear translocation of p65 subunit of NF-κB. In addition, MF attenuated the AP-1 luciferase activity and phosphorylation of ERK, JNK, and p38 MAP kinases. Taken together, these results suggest that the anti-inflammatory effect of MF is associated with the suppression of NO production and iNOS expression through the down-regulation of NF-κB activation and MAPK signaling pathway in LPS-stimulated RAW264.7 macrophages.

The phenolic compounds of many fruits have been known to be efficient cellular protective antioxidants. In this study, antioxidative and antiviral properties of flowering cherry cultivars (Prunus yedoensis, Prunus sargentii, Prunus lannesiana, and Prunus cerasus) in Korea were investigated. The antioxidant property was assayed for specific activities including 2,2-diphenyl-1-picrylhydrazyl (DPPH) hydroxy radical scavenging activity, reducing power capacity, and superoxide dismutase (SOD) like activity. In addition, antiviral activity was determined by inhibition studies on the infection cycle of porcine epidemic diarrhea virus (PEDV), measured as minimum concentration of cherry extracts that inhibited 50% of cytopathic effect (CPE) on PEDV. Our results show that the four varieties of cherries contain substantially high antioxidants and antiviral activities. In particular, P. cerasus contains higher antioxidants and antiviral activities as well as polyphenolic content than other varieties. Our data indicate that Korean native cherry cultivars could be beneficial supplements of dietary antioxidants and natural antiviral agents.

Daily consumption of an antioxidant-rich leafy vegetable mix (LVM) was assessed for beneficial effects on plasma lipid profiles, tissue lipid peroxidation, and oxidative DNA damage in C57BL/6J mice fed a high fat and high cholesterol diet (20% fat and 1% cholesterol, wt/wt) for 4 weeks. The LVM contained beet leaf, angelica, red leaf lettuce, dandelion, green cos lettuce, lollo rosso, romaine lettuce (12.5%, respectively), scotch kale, and red kale (6.25%, respectively). The mice (n = 16) were randomly divided into either the control (high fat and cholesterol diet without LVM) or the LVM (high fat and cholesterol diet with 8% LVM supplement) groups after a 1-week acclimation. Lipid peroxidation as measured by thiobarbituric acid-reactive substances in the plasma, liver, heart, and kidney was significantly lower. Antioxidants (glutathione and beta-carotene) and antioxidant enzyme activities (glutathione peroxidase, glutathione reductase, and superoxide dismutase) were improved in mice fed LVM diet. In the comet assay, tail extent moment, olive tail moment, and tail length were significantly less in the hepatocyte and lymphocyte DNA of the LVM group, indicating the beneficial effect of LVM on the resistance of hepatocytes and lymphocytes DNA to oxidative damage. Findings from the present study suggest that dietary supplementation with LVM may be useful for protecting cells from lipid peroxidation and oxidative DNA damage.

The structural importance of the acyl group in lysophosphatidylcholine (LPC) as substrate of purified bovine lysophospholipase D (lysoPLD) was investigated. Among LPCs with saturated acyl chains, the K(m) value decreased according to the length of the acyl chain (C12-C16) up to the palmitoyl group, while the V(m) value showed no remarkable change. But, the extension of the acyl size to C18, as observed with 1-stearoyl LPC (K(m), 8.5 mM), rather resulted in a remarkable increase in the K(m) value. Meanwhile, the introduction of one double bond in the C18 saturated acyl chain led to a remarkable reduction in the K(m) value, as observed with 1-oleoyl LPC (K(m), 0.48 mM). Furthermore, 1-linoleoyl LPC (K(m), 56 microM) with two double bonds exhibited a smaller K(m) value than 1-oleoyl LPC, suggesting that the unsaturation degree might be important in augmenting the binding affinity of LPCs. A similar phenomenon was also observed with 1-arachidonoly LPC (K(m), 79 microM) or 1-docosahexaenoyl LPC (K(m), 36 microM). Overall, the order of catalytic efficiency (V(m)/K(m) value) of those LPCs seemed to be affected by the K(m) value rather than the V(m) value, which differed by at most threefold among LPC derivatives. Next, the introduction of a hydroperoxide group into 1-linoleoyl-LPC or 1-arachidonoyl LPC led to a further reduction in K(m) values (1-hydroperoxylinoleoyl LPC, 26 microM; 1-hydroperoxyarachidonoyl LPC, 33 microM), accompanied by a further increase in the V(m)/K(m) values. Additionally, phosphatidylcholines (PCs) with an oxidized acyl chain at sn-2 position were found to be efficient as 1-palmitoyl LPC as substrates of lysoPLD. Taken together, the catalytic efficiency of LPCs or oxidized PCs as substrates of lysoPLD seems to be determined by the property of the acyl chain, length of the acyl chain, unsaturation degree and oxidation status.

Lysophospholipase D (lysoPLD), generating lipid mediator lysophosphatidic acid (LPA) from lysophosphatidyclcholine (LPC), is known to be inhibited by lysophosphatidic acids. Meanwhile, some plant lipids are known to contain lysophospholipids as minor components. Therefore, it is interesting to test whether edible seed samples, rich in phospholipids, may contain lysophospholipids, which express a strong inhibition of lysoPLD activity. First, the structural importance of fatty acyl group in LPAs was examined by determining the inhibitory effect of various LPAs on bovine lysoPLD activity. The most potent in the inhibition of lysoPLD activity was linoleoyl-LPA ( K i, 0.21 microM), followed by arachidonoyl-LPA ( K i, 0.55 microM), oleoyl-LPA ( K i, 1.2 microM), and palmitoyl-LPA ( K i, 1.4 microM), based on the fluoresecent assay. The same order of inhibitory potency among LPA analogs with different acyl chains was also found in the spectrophotometric assay. Subsequently, the extracts of 12 edible seeds were screened for the inhibition of lysoPLD activity using both spectrophotometric and fluorescent assays. Among seed extracts tested, the extract from soybean seed, sesame seed, or sunflower seed (30 mg seed weight/mL) was found to exhibit a potent inhibition (>80%) of lysoPLD activity. In further study employing ESI-MS/MS analysis, major LPA components in seed extracts were identified to be 1-linoleoyl LPA, 1-oleoyl LPA, and 1-palmitoyl LPA with 1-linoleoyl LPA being more predominant. Thus, the potent inhibition of lysoPLD activity by seed extracts might be ascribed to the presence of LPA with linoleoyl group rather than other acyl chains.

The observed Enterobacter sakazakii D10-values for tryptic soy broth and dehydrated powdered infant formula were 0.27 +/- 0.05 and 0.76 +/- 0.08 kGy, respectively. A decrease of approximately 3 log in the dehydrated powdered infant formula was obtained by irradiation with 3.0 kGy or rehydration with hot water at 80 degrees C. No recoverable bacteria were found in the powdered infant formula irradiated at 5.0 kGy and stored, either before or after rehydration. A radiation dose of up to 5.0 kGy had no marked effect on the sensory properties of the dehydrated powdered infant formula after rehydration and heating. Gamma radiation could potentially be used to inactivate E. sakazakii in dehydrated powdered infant formula; however, nutritional studies need to be conducted before the use of radiation can be recommended.

Volatile N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) in irradiated pepperoni and salami sausages were determined using a gas chromatography coupled to a thermal energy analyzer (GC-TEA). These fermented sausages with aerobic or vacuum packaging were irradiated at 0, 5, 10, and 20 kGy, and then stored for 4 weeks at 4 degrees C. Both NDMA and NPYR in the fermented sausage were significantly reduced by irradiation. The vacuum packaging showed significantly lower (P < 0.05) N-nitrosamine levels than that of the aerobic ones. After storage, the contents of NDMA and NPYR in the irradiated sausage were lower than those of the non-irradiated control. Results indicated that a high dose of irradiation (>10 kGy) was needed to reduce the carcinogenic N-nitrosamines in the fermented sausage during storage and the GC-TEA analysis was effective in determining the N-nitrosamines in irradiated meats even at low trace levels.

This study was conducted to evaluate the reduction of an egg allergen in a cake containing gamma-irradiated egg white. A white layer cake was manufactured by a commercial formula with 10- or 20-kGy-irradiated egg white. Enzyme-linked immunosorbent assays (ELISAs) with immunoglobulin (Ig) E from egg-allergic patients and with rabbit anti-ovalbumin IgG were used to identify and quantify ovalbumin (OVA) in the samples. Concentrations of native OVA detected by IgE and IgG in the control were 432.88 and 375.46 microg/g sample, respectively. However, native OVA in samples with 10- and 20-kGy-irradiated egg white was detected at low concentrations (14.27 and 8.78 microg/g, respectively) by IgE (P < 0.05); IgG recognized OVA more often in 10- and 20-kGy samples than in controls. Conformational cleavage of OVA by irradiation could explain the IgG result. The results appear to suggest that irradiating egg white might reduce its allergenicity, which could be used in the production of baked goods of reduced allergenicity.

Lipid oxidation and color stability of meats treated with irradiated phytic acid were investigated during storage for 2 weeks at 4 degrees C. The phytic acid in deionized distilled water (DDW) was degraded by irradiation at 10 and 20 kGy, and the irradiated phytic acid showed a strong antiradical activity. For measuring the antioxidant effects of irradiated phytic acid in food models, beef and pork were prepared with DDW (control), irradiated (10 and 20 kGy) or non-irradiated phytic acid, and ascorbic acid as a model system. Irradiated phytic acid significantly inhibited the lipid oxidation in meats compared to the control and ascorbic acid treated samples during storage (P < 0.05). The redness of the meats treated with phytic acid had a higher value than did the control and ascorbic acid treated samples, but a significant difference was not observed in the samples treated with phytic acid regardless of irradiation treatment. Irradiated phytic acid was also effective in inhibiting the loss of heme iron and metmyoglobin formation during storage. Results indicated that irradiation might be helpful for improving the antioxidant activity of phytic acid in meats.

Gossypol dissolved in methanol (0.25 and 0.5 mg/ml) was gamma-irradiated at 0, 5, 10, and 20 kGy. The gossypol content was significantly reduced by irradiation in a dose-dependent manner. Ames test performed with nonirradiated and irradiated gossypol solutions was negative at the level of 0.1, 0.5, 1, 10, 50, and 100 microg gossypol/plate. At the gossypol concentration of 2.5 microg/ml, the blastocysts formation rate of mice embryo were decreased by a factor of two as compared with the control, but irradiation at 20 kGy increased the blastocysts formation, resulting in no difference from the control. Addition of gossypol to oil emulsion system or oil showed a prooxidative effect of lipids at the beginning stage by increasing 2-thiobarbituric acid reactive substances (TBARS) and peroxide value but irradiation of the gossypol solution decreased the oxidative changes significantly as compared with the nonirradiated one. Results indicated that irradiation decreased the gossypol concentration dissolved in methanol, resulting in a reduction of embryotoxicity in mice.

This study was carried out to evaluate the changes in the allergenic and antigenic properties of hen's egg albumin (ovalbumin [OVA]) with the combination of heat and gamma irradiation treatment. OVA solution samples were treated by (i) heating (sample 1), (ii) irradiation after heating (sample 2), and (iii) heating after irradiation (sample 3). Samples were isothermally heated and irradiated at the absorption dose of 10 kGy. Competitive indirect enzyme-linked immunosorbent assays (ELISAs) were performed with blood serum to test the ability of treated OVA to bind to immunoglobulin E (IgE) and mouse murine monoclonal antibody (IgG). OVA's ability to bind to mouse IgG changed upon heating at 75 degrees C, and its ability to bind to egg-allergic IgE changed upon heating at 80 degrees C. The ELISAs showed that egg-allergic IgE did not recognize OVA very well when heated at > or = 80 degrees C, while mouse IgG retained better activity under these conditions. Egg-allergic IgE binding was low both for OVA samples treated by heating and for samples treated by irradiation followed by heating. These results show that allergies induced by OVA could be effectively reduced by the combination of heat and gamma irradiation treatment.

This study was conducted to evaluate the effect of a treatment combining gamma radiation and heating on the allergenic properties of hen's egg ovomucoid (OM) under basic pH conditions. OM solutions of 2.0 mg/ml with pHs of 7.0, 9.0, and 10.0 were gamma irradiated at 10 kGy, heated at 100 degrees C for 15 min, or both. Half of the treated pH 10.0 sample solution was restored to pH 7.4 by dialysis. OM solutions were tested by a competitive direct enzyme-linked immunosorbent assay formatted with immunoglobulin E from egg-hypersensitive patients. An equation was obtained for quantifying intact OM from the standard curve, and the detected concentration of intact OM was calculated. The concentration of intact OM decreased with irradiation or heating, and the rate of the decrease was higher for a basic pH condition than for the physiological condition. The combination of irradiation and heating was very effective in reducing the amount of intact OM regardless of the pH condition. After treatment, the restoration of the pH to 7.4 did not affect the concentration of OM. The results of this study indicate that a combination of irradiation and heating might be an effective method for reducing egg hypersensitivity resulting from OM.

Quality properties in emulsion-type sausage stuffed into irradiated natural casing were studied. Fresh salted and semidried natural pork and lamb casing was washed and irradiated at 0, 3, and 5 kGy by gamma-ray and emulsion-type pork sausage (Brattella Weiss Wurst) was manufactured. The sausage was stored in a 4°C refrigerator. The numbers of total aerobic bacteria, Enterococcus and coliform bacteria in the irradiated natural casing or sausage prepared from irradiated casing were significantly decreased or eliminated compared to those of the nonirradiated control. The D(10) values of total aerobic bacteria of the pork and lamb casing were 0.87 and 0.92 kGy, respectively. The vacuum-packaged sausages made with irradiated casings had a higher 2-thiobarbituric acid reactive substances value than that of the nonirradiated controls only at 5-day with pork casing and at 10-day with lamb casing. The total working force for shear of the sausages was decreased in both irradiated casings but the sensory evaluation showed no difference. Therefore, the gamma irradiation was a useful technique to sanitize the natural pork and lamb casings and to extend shelf-life, primarily microbial quality, of the sausage made with natural casings.

This study was carried out to evaluate the application of food irradiation technology as a method for reducing milk allergies. Bovine alpha-casein (ACA) and beta-lactoglobulin (BLG) were used as milk proteins. Using milk-hypersensitive patients' immunoglobulin E (IgE) and rabbit IgGs individually produced to ACA and BLG, the changes of allergenicity and antigenicity of irradiated proteins were observed by competitive indirect enzyme-linked immunosorbent assay. Allergenicity and antigenicity of the irradiated proteins were changed with different slopes of the inhibition curves. The disappearance of the band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and increase of the turbidity showed that solubility of the proteins decreased by radiation, and this decrease might be caused by agglomeration of the proteins. These results indicated that epitopes on milk allergens were structurally altered by gamma irradiation.

The effects of gamma radiation on sensory quality, microbial population, and chemical properties of salted and fermented squid were investigated. Squid (Todarodes pacificus) was sliced, washed, and then salted with 5, 10, and 20% (wt/wt) sodium chloride. Salted squid was irradiated with dosages of 0, 2.5, 5.0, and 10 kGy of gamma radiation and fermented at 15 degrees C for 50 days. Proximate composition, salinity, water activity, sensory evaluation, and total microbiological populations were examined. Chemical analyses providing information on degree of fermentation, such as amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA), and hypoxanthine (Hx) were also conducted. Irradiated squid was not different in proximate composition, salinity, and water activity from nonirradiated squid. Sensory evaluation scores, total bacteria populations, and pH values were variable depending on salt concentration and irradiation dose. During fermentation, AN, VBN, TMA, and Hx contents increased rapidly as the salt concentration and irradiation dose decreased. Specifically, these chemical compounds of salted and fermented squid prepared with 10% salt and 10 kGy of gamma radiation maintained the appropriate level of fermentation. The present results showed that the combination of low salt concentration (10%) and gamma radiation was effective in processing salted and fermented squid and extending its shelf life compared to control (20% of salt) without adding any food additives.

This study was undertaken to determine if gamma irradiation can circumvent the need for sodium nitrite to obtain and maintain the desired color of pork loin ham. A dose of 5 kGy was observed to be as effective as the use of 200 ppm of sodium nitrite to provide and maintain the desired color of the product for 30 days. Peroxidation of the product was reduced with addition of sodium nitrite but increased with irradiation. However, organoleptic quality of the irradiated ham without added sodium nitrite was acceptable.

To improve the storage safety of two types of ground beef patty popular in Korea (general beef patties and bulgogi patties), we added various antioxidants (200 ppm; including butylated hydroxyanisole, ascorbyl palmitate, alpha-tocopherol, and beta-carotene) to typical formulations of patties, cooked the patties to 70 degrees C, and irradiated them at a dose of 1.5 or 3 kGy. During 30 d of storage at 5 degrees C, the number of aerobic bacteria and lactic acid bacteria were determined using total aerobic plate count and phenyl ethyl alcohol-sucrose agar, respectively. The concentration of thiobarbituric acid was also determined in each type of patty. No colonies were observed in patties irradiated at 3 kGy regardless of which antioxidant was added. In control patties and patties with butylated hydroxyanisole that were irradiated at a dose of 1.5 kGy, growth of microorganisms appeared to be more rapid than in patties with natural antioxidants. The microbiological safety of nonirradiated patties could not be ensured for a period of 20 d. Lipid oxidation was retarded in both types of patty when an antioxidant was added. Ascorbyl palmitate had the strongest antioxidant effect among the natural antioxidants. However, butylated hydroxyanisole was more effective than ascorbyl palmitate when used in an equal amount.

A study was conducted to investigate the reduction and elimination of Escherichia coli O157:H7 by the effects of gamma irradiation and ozone treatment. Log phase cells were found to be more sensitive to gamma irradiation than stationary phase cells. E. coli O157:H7 was found to be considerably more resistant to irradiation at -18 degrees C than at 20 degrees C. The D values for this organism for treatment with ozone in tryptic soy agar were higher than those for treatment with ozone in phosphate buffer. Gamma irradiation at a dose of 1.5 kGy or ozone treatment at a concentration of 3 to 18 ppm for 20 to 50 min was required to assure the elimination of E. coli O157:H7.

The effects of gamma irradiation and ozone treatment on microbiological and physicochemical properties of bee pollen were investigated. Gamma irradiation at 7.5 kGy reduced the total microbial loads below detection levels (>10(2) CFU g(-1)), but after ozone treatment of up to 18 ppm for 8 h the total aerobic bacteria were found in concentrations of more than 10(3) CFU g(-1). Physicochemical properties such as amino acid and fatty acid composition, thiobarbituric acid value, mineral content, and pigment were not significantly changed by gamma irradiation, whereas ozone treatment caused significant changes in fatty acid composition, thiobarbituric acid value, and pigment by lipid oxidation and decoloration (P < 0.05).