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Graphene has generated tremendous interest over the past decade because of its extraordinary properties and potential applications. In this work, dispersible graphene flakes were successfully fabricated via a one-step process using a thermal plasma jet system. The graphene flakes fabricated by injection of ethylene gas as a carbon source (500 sccm) were very pure, contained no oxygen, and were few layered. Although their average size was larger than 100 nm, they were well-dispersed in organic solvents by sonication. The production rate based on the collected amount was approximately 1.5 g/h. As a representative application, thin films of the graphene flakes were fabricated on fluorine-doped tin oxide (FTO) glass using three deposition techniques. The resulting dye-sensitized solar cell with a graphene flake/FTO counter electrode exhibited a power conversion efficiency of 9.03%, which was similar to the efficiency of the solar cell with a conventional Pt/FTO counter electrode. Therefore, our graphene flake/FTO electrode could be used as a substitute for the conventional Pt/FTO counter electrode for DSSCs as graphene flakes are much less expensive than Pt. In addition to this specific application, dispersible graphene could be used in the fabrication of composites as well as various energy storage, sensor, and electronic devices. [ABSTRACT FROM AUTHOR]

Abstract: The radiation pasteurization process was performed to improve the microbiological quality of fresh vegetable juice. Carrot and kale juice were irradiated and their microbiological, nutritional, and sensory properties were evaluated. The contaminating bacteria in the juices before irradiation ranged from 106 to 107 CFU/ml. All the aerobic and coliform bacteria in the carrot juice were eliminated by irradiation at a dose of 3kGy, whereas about 102 CFU/ml of the bacteria survived in the kale juice irradiated at up to 5kGy. However, the cells that survived from irradiation in the kale juice did not grow, whereas those of the non-irradiated samples reached 109 CFU/ml after 3 days of storage at 10°C. Amino acids were stable at up to 5kGy of an irradiation. Radiation resulted in a dose-dependent reduction of the ascorbic acid content. However, the contents of the total ascorbic acid, including dehydroascorbic acid, were stable at up to 3kGy of an irradiation. The sensory evaluation results immediately after irradiation were not different in any of the samples. At a 3-day storage, the sensory quality of the irradiated juice was adequate, while the quality of the non-irradiated control was deteriorated. [Copyright &y& Elsevier]

Three prepared seafood products for manufacturing a laver (dried seaweed) roll, a traditional and rapidly growing ready-to-eat meal in Korea, were selected and the effects of irradiation treatment for eliminating pathogens of public health significance were investigated. The pathogens tested were Salmonella Typhimurium, Eseherichia coli, Staphylococcus aureus, and Listeria ivanovii. The radiation sensitivity (D10-Values or the dose required to inactivate 90% of a population) of these organisms ranged from 0.23 to 0.62 kGy in imitation crab leg, 0.31 to 0.44 kGy in surimi gel, and 0.27 to 0.44 kGy in dried seaweed. The growth of all four test organisms inoculated (108 CFU/g) into these foods was inhibited by irradiation during 24 h of postirradiation storage regardless of the temperature (10, 20, and 30°C). L. ivanovii was not detected after a 3-kGy treatment, but the other pathogens were not detected following irradiation at 2 kGy. These studies indicated that low-dose irradiation (2 kGy or less) of prepared seafood materials can keep them microbiologically safe before manufacturing a ready-to-eat prepared meal, a laver roll. [ABSTRACT FROM AUTHOR]

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 µg/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 µg/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. [ABSTRACT FROM AUTHOR]

We investigated the usefulness of hydrocarbons and 2-alkylcyclobutanones as markers for irradiated, dried shrimps. A method was developed to detect the irradiation of dried shrimps (Penaeus aztecus) by identifying radiation-induced hydrocarbons and 2-alkylcyclobutanones extracted from dried shrimps, which were separated by Florisil column chromatography and identified by a method using gas chromatography/mass spectrometry. Radiation-induced hydrocarbons and 2-alkylcyclobutanones are formed from the fatty acids of the irradiated fats. The quantity of the hydrocarbons and 2-alkylcyclobutanones formed from some fatty acids is related to the composition of fatty acids in a sample. The concentrations of hydrocarbons and 2-alkylcyclobutanones increased with radiation dose. The major hydrocarbons in the irradiated, dried shrimps were 1tetradecene and pentadecane from palmitic acid; small amounts of heptadecane and 1-hexadecene from stearic acid; and 8heptadecene and 1,7-hexadecadiene from oleic acid. 2-(5'-Tetradecenyl)cyclobutanone, one of the 2-alkylcyclobutanones, was present at the highest concentration. The radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at radiation doses of 0.5 kGy and greater. These compounds were not detected in nonirradiated, dried shrimps. [ABSTRACT FROM AUTHOR]

Effects of gamma irradiation on the physiological activity of Korean soybean fermented foods were investigated. Chungkookjang, the whole cooked soybean product and Doenjang, soybean paste were purchased and irradiated at 5, 10 and 20 kGy of absorbed doses. The physiological activity was evaluated by angiotensin converting enzyme inhibition, xanthine oxidase inhibition, tyrosinase inhibition and radical scavenging ability and results indicated that at 10 kGy or below did not show any significant change on physiological activities by irradiation. [Copyright &y& Elsevier]

To evaluate the effects of gamma irradiation on the processing properties of meat products, emulsion-type sausage, beef patties and pork loin ham were manufactured. Most contaminated bacteria were killed by 3 kGy-irradiation to raw ground beef, and sausage can be manufactured with desirable flavor, a reduction of NaCl and phosphate, and extension of shelf life using gamma irradiation on the raw meat. The beef patties were manufactured with the addition of antioxidants (200 ppm), BHA, ascorbyl palmitate, α-tocopherol, or β-carotene, and gamma-irradiation. Retardation of lipid oxidation appeared at the patties with an antioxidant. A dose of 5 kGy was observed to be as effective as the use of 200 ppm NaNO2 to provide and maintain the desired color of the product during storage. After curing, irradiation, heating and smoking could extensively prolong the shelf life of the hams. [Copyright &y& Elsevier]

Abstract: Total occlusion of the left main trunk (LMT) frequently results in sudden cardiac death. As a result, it is rarely observed on coronary arteriogram. There are only a few reports on chronic total occlusion of the LMT. Most patients present with recent, severe angina, but it is not easy to distinguish chronic total occlusion of the LMT from other types of severe coronary heart diseases. Here, we report a very rare case of chronic total occlusion of the LMT. The patient is a 38-year-old female with a history of three normal deliveries. Chronic total occlusion of the LMT was suspected on coronary arteriogram 2years previously in the other hospital; however, she continued working as a part-time employee at a supermarket. She was referred to our hospital because of slightly increased effort angina and shortness of breath. The final diagnosis and the site of occlusion were determined by three-dimensional computed tomography (3-D CT). The patient underwent coronary artery bypass graft (CABG) surgery, and ischemic symptoms completely disappeared. [Copyright &y& Elsevier]

Abstract: Since the first irradiated food was approved and commercialized in 1987, most of Koreans still do not accept the irradiated food until now. It is reasoned that there are the ambiguous fear of nuclear technology and the confusion between irradiated food and radioactive-contaminated food. This investigation was carried out to examine the acknowledgement of irradiated food in Korean housewives and to study how to enhance the intention of purchasing the irradiated food. About 600 Korean housewives participated in the survey on the irradiated food in 2007, more than two-thirds of them were not aware of irradiated food. One hundred and fifty-four women who had known of irradiated food were subjected to an experiment for the source of information about irradiated food (e.g., lecture by an expert, video-watching and book-reading) in order to explore which type of information channel is the most effective in eliciting purchase intention. The result showed that the women group who had heard the lecture by an expert indicated the highest intention to purchase irradiated food, followed by the video-watching and the book-reading groups. In addition, the acceptance of the irradiated food had shown to lead the support for nuclear industry. [Copyright &y& Elsevier]

The irradiation of natural resources such as green tea leaf, persimmon leaf, licorice root and stolon or Lonicera japonica improved the color of the extract, resulting in a higher applicability without any adverse change to the beneficial functions such as the inhibitory effects of oxidation, melanin hyperpigmentation on the skin, and others. To investigate the application of irradiated natural resources for a real cosmetic composition, the physiological activities of irradiated green tea leaf extract powder dissolved in butylene glycol and ethanol were compared to a commercial green tea extract product. Furthermore, a cream lotion was manufactured using the powder and the physiological activities were compared. Results showed that the irradiation of the green tea leaf extract and the freeze-dried powder from the extract had the same physiological activities as the commercial product in a cosmetic composition. [Copyright &y& Elsevier]

To observe the changes of immunogenicity and antigenicity of gamma-irradiated ovalbumin (OVA), an antigen (Ag) solution (2.0 mg/ml) was prepared and irradiated with the absorbed doses of 3 and 10 kGy. Immunoglobulin G (IgG) was produced for each Ag. 0, 3 and 10 kGy-IgG were individually reacted against 3 Ags in an ELISA cross reactivity test. Cross reactivity of each IgG was significantly different for each Ag. Especially the 10 kGy-irradiated OVA lost most antigenicity compared to the 0 kGy-IgG. [Copyright &y& Elsevier]

This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods. [Copyright &y& Elsevier]

In the electronic packaging technology, lead-free solders have been widely used to replace lead-based solders because of the toxicity of lead. Among the investigated lead-free solders, the Sn–58Bi solder has been considered as a highly promising candidate because of its low-melting temperature, high tensile strength and good creep resistance. However, the Sn–58Bi solder has poor ductility and shock absorbance. To enhance the mechanical properties of the Sn–58Bi solder, epoxy resin is mixed with the Sn–58Bi solder. The advantages of the Sn–58Bi solder with epoxy are good reliability and no need of a cleaning process. This study elucidated not only the mechanical properties of the Sn–58Bi epoxy solder but also the effects of the epoxy during the reflow process by conducting a shear test and a board-level drop test. The shear strength of the Sn–58Bi epoxy solder was about 2 times higher than that of the Sn–58Bi solder. In result of the drop test, the Sn–58Bi solder specimen failed under the 10th drop. However, the number of drops of the Sn–58Bi epoxy solder was over 100 drops without failure. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the effect of gamma irradiation on Burkholderia thailandensis (Burkholderia pseudomallei surrogate; potential bioterrorism agent) survival under different levels of NaCl and pH. B. thailandensis in Luria Bertani broth supplemented with NaCl (0–3%), and pH-adjusted to 4–7 was treated with gamma irradiation (0–0.5kGy). Surviving cell counts of bacteria were then enumerated on tryptic soy agar. Data for the cell counts were also used to calculate D 10 values (the dose required to reduce 1logCFU/mL of B. thailandensis). Cell counts of B. thailandensis were decreased (P<0.05) as irradiation dose increased, and no differences (P≥0.05) in cell counts of the bacteria were observed among different levels of NaCl and pH. D 10 values ranged from 0.04 to 0.07kGy, regardless of NaCl and pH level. These results indicate that low doses of gamma irradiation should be a useful treatment in decreasing the potential bioterrorism bacteria, which may possibly infect humans through foods. [Copyright &y& Elsevier]

Comparative effects of gamma irradiation and methyl bromide (MeBr) fumigation were determined for fresh chestnut on mortality of pests and quality stability. Chestnut was exposed to both irradiation at 0–10 kGy and MeBr fumigation in commercial conditions, and then subjected to the corresponding study during storage at 5°C for 6 months. Pests with quarantine importance for chestnut were found Curculio sikkimensis Heller and Dichocrocis punctiferalis Guenee, which showed 100% mortality by MeBr at the 3rd day after fumigation and by irradiation at 0.5 kGy in about 4 weeks. Sprouting was controlled for 6 months with treatments of 0.25 kGy or more and of MeBr, but rotting rate dramatically increased from 2 months after fumigation. Irradiation over 1 kGy as well as fumigation significantly caused changes in the color of stored chestnut. Considering the cumulative mortality of chestnut pests, irradiation at the range of 0.5 kGy is recommendable as one of alternatives to MeBr fumigation for both quarantine and sprout control purposes. [Copyright &y& Elsevier]

We have investigated ESR spectra of fermented soybean paste irradiated at 77 K and compared with those of soybean protein isolate and soybean oil. The influences of irradiation dose, moisture content and heating after irradiation on the free radical concentration and species were examined. Four different carbon type free radicals, FR1–FR4, were identified as the product of amino acid decomposition. In the case of FR1, the doublet line arises from the hydrogen atom on the β-carbon adjacent to the carbonyl free radical. It disappeared at 150 K. FR2 was most abundant and disappeared at 190 K in wet soybean paste (WSP) and at 210 K in dry soybean paste (DSP), respectively. The radical FR4 originated from decarboxylation and deamination of amino acids, which disappeared at 210 K in both WSP and DSP. FR3 was assumed to be formed by the damage of amino acid side chains. The radical ·OH was originated from water molecules, and was not observed in dry system. Sulfur radical was stable even at room temperature observed in both wet and dry systems. Aldehyde radical must be originated from the chemical reactions of enzymatic hydrolysates of soybean [Copyright &y& Elsevier]

Abstract: Numerous studies have shown various relationships between foods with a high nutritional value and a robust immune response, particularly studies that have focused on host protection and cytokine networks. This study aimed to clarify the role played by the procyanidin trimer C1 in innate and adaptive immunity. Procyanidin C1 did not exert cytotoxicity at concentrations ranging from 7.8 to 62.5μg/ml in macrophage cells; therefore, concentration of 62.5μg/ml was used as the maximum dose of procyanidin C1 throughout subsequent experiments. Procyanidin C1 enhanced inducible nitric oxide synthase-mediated nitric oxide production in a concentration-dependent manner. In addition, procyanidin C1 functionally induced macrophage activation by augmenting the expression of cell surface molecules (CD80, CD86, and MHC II) and proinflammatory cytokine production (tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6) via activation of mitogen-activated protein kinase (MAPK), e.g., p38, ERK, and JNK and nuclear factor (NF)-κB signaling pathways. Interestingly, procyanidin C1 effectively polarized T helper type 1 (Th1) by secreting Th1-mediated cytokines (interferon-γ, IL-12p70, and IL-2) and inducing splenocyte proliferation, indicating that procyanidin C1 contributes to Th1 polarization of the immune response. Accordingly, these findings confirms that the procyanidin C1 induces macrophage activation via NF-κB and MAPK pathways, leading to Th1 polarization in murine splenocytes, which suggests that procyanidin C1 regulates innate and adaptive immunity by macrophage activation and Th1 polarization. [Copyright &y& Elsevier]

Abstract: Natural products and dietary components rich in polyphenols have been shown to reduce inflammation; however, the molecular mechanisms underlying this anti-inflammatory activity are not completely characterized, and many features remain to be elucidated. This research was carried out to clarify the potential role of procyanidin trimer C1 in the anti-inflammatory effect of polyphenols. Procyanidin C1 inhibited inducible nitric oxide synthase-mediated nitric oxide production and the release of pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor-α) in lipopolysaccharide (LPS)-induced macrophages. Treatment with procyanidin C1 resulted in a significant decrease in prostaglandin E2 and cyclooxygenase-2 levels, as well as the expression of cell surface molecules (CD80, CD86, and MHC class II), which was induced by LPS. Furthermore, our data demonstrated that the anti-inflammatory effect of procyanidin C1 occurs through inhibition of mitogen-activated protein kinase (p38 and c-Jun N-terminal kinase) and nuclear factor-κB signaling pathways. These 2 factors play a major role in controlling inflammation, through toll-like receptor 4, suggesting that procyanidin C1 plays a potent role in promoting anti-inflammatory activity in macrophages. These results represent a novel and effective therapeutic intervention for the treatment of inflammatory disease. [Copyright &y& Elsevier]

Abstract: Pork is known as an allergenic food with porcine serum albumin (PSA, 66kDa) representing the major allergen. This study was conducted to investigate the change in antigenicity of PSA in gamma-irradiated sausage extract treated with pepsin and trypsin. Sausage products (A and B) were irradiated at 1, 3, 10, and 20kGy. After irradiation, sausage proteins were extracted and digested with pepsin (1:200, 30min) and trypsin (1:300, 5, 30, 60, 90, and 120min). The binding ability of PSA in extracts of the irradiated sausages (A and B) decreased by over 3kGy relative to the binding ability of PSA in extracts of intact sausages and showed no notable differences when the dose of radiation ranged from 3 to 20kGy. After treatment with pepsin and trypsin, the binding ability of PSA in extracts of the irradiated sausages was decreased more relative to that of intact sausages and showed no significant differences when the period of trypsin treatment is increased or when the dose of irradiation is increased. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) results indicated that there was no visible change in the intensity of the PSA band in extracts of the irradiated sausages. After pepsin and trypsin treatment, the intensity of PSA band faded with increasing doses of irradiation. In conclusion, antigenicity of PSA in pork sausages could be reduced by gamma irradiation. [Copyright &y& Elsevier]

Abstract: Silk fibers have proven to be effective in many clinical applications as well as for clothing. In addition to the substantial effect of silk fibers, the present study was conducted to explore its importance in a new dimension to reinforce the effects of its physiological function regarding anti-tumor activity and immune response with gamma-irradiated silk fibroin (GISF). The cytotoxicity results showed that pre-treatment of GISF in the mouse peritoneal macrophages (MPM) indicated a higher proliferative effect than that of non-irradiated silk fibroin (NISF) in a concentration-dependent manner. Based on the cytotoxicity result of MPM, GISF (50 and 150kGy) was selected for an ex vivo study in an animal (C57BL6) system and evaluated about whether the non-specific immune response was also related to GISF. GISF (50 and 150kGy) augmented immune responsiveness via activation of NK cells, T lymphocytes proliferation, NO production, and cytokine level, such as IL-6, IL-2, IL-12, IFN-γ, TNF-α, as compared with NISF, which strongly suggested that GISF significantly augmented an important element of all aspects of the innate and adaptive immune system. Therefore, from these results, it seems likely that the GISF will play a potent role in eliciting the effect of the non-specific immune response and anti-tumor activity as a value-added product in the medical industry. [Copyright &y& Elsevier]

Abstract: This study was performed to elucidate the anti-proliferative effects and the apoptotic mechanisms of extracts from Lethariella zahlbruckneri in HT-29 human colon cancer cells. Both the acetone extract (AEL) and methanolic extract (MEL) of L. zahlbruckneri decreased viable cell numbers in a dose- and time-dependent manner in HT-29 cells. The AEL showed stronger cytotoxicity than MEL. Cell death induced by AEL increased cell populations in the sub-G1 phase, as well as the formation of apoptotic bodies and nuclear condensation, whereas MEL did not. Therefore, the potential of AEL to induce apoptosis was examined. Apoptosis induced by AEL was associated with the activation of initiator caspases-8 and -9, as well as the effector caspase-3. AEL stimulated Bid cleavage. This indicated that the apoptotic action of caspase-8-mediated Bid cleavage leads to the activation of caspase-9. AEL increased the expression of the pro-apoptotic protein, Bax, and decreased the expression of the anti-apoptotic protein, Bcl-2. AEL also increased the expression of the caspase-independent mitochondrial apoptosis factor, AIF, in HT-29 cells. These results indicate that AEL inhibited HT-29 cell proliferation by inducing apoptosis, which might be mediated via both caspase-dependent and -independent pathways. [Copyright &y& Elsevier]

Abstract: Addition of calcium lactate and vitamin C, a mild heating, deep-freezing, and gamma irradiation at 25kGy were conducted to prepare Kimchi as a ready-to-eat space food. It was confirmed that the space food was sterilized by an irradiation at 25kGy through incubation at 37°C for 30days. The hardness of the Space Kimchi (SK) was lower than the untreated Kimchi (CON), but higher than the irradiated Kimchi (IR). Also, this result was supported by the scanning electron microscopic observation. Sensory attributes of the SK were similar to CON, and maintained during preservation at 35°C for 30days. According to the Ames test, Kimchi sterilized with a high-dose irradiation exerted no mutagenic activity in the bacterial strains of Salmonella typhimurium. And, the SK was certificated for use in space flight conditions during 30days by the Russian Institute of Biomedical Problems. [Copyright &y& Elsevier]

Abstract: Nutrition bar, Ramen (ready-to-cook noodle), and two Korean traditional foods (Kimchi, fermented vegetable; Sujeonggwa, cinnamon beverage) have been developed as space foods using high-dose gamma irradiation. Addition of calcium lactate and vitamin C, a mild heating, deep-freezing, and gamma irradiation at 25kGy were conducted to prepare Kimchi as a ready-to-eat space food. Sterilization of Space Kimchi (SK) was confirmed by a microbiological test. The hardness of the Space Kimchi was lower than the untreated Kimchi (CON), but higher than the irradiated only Kimchi. Sensory attributes of the SK were similar to CON, and maintained during preservation at 35°C for 30 days. The optimal doses for eliminating the contaminated microbes and maintaining the qualities of the Nutrition bars, Ramen, and Sujeonggwa were determined at 15, 10 and 6kGy, respectively. All the Korean space food were certificated for use in space flight conditions of 30 days by the Russian Institute for Biomedical Problems. [Copyright &y& Elsevier]

Abstract: A study was carried out to find the effect of γ-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix (Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, (E)-carveol, (E,E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of γ-irradiation on medicinal herb. [Copyright &y& Elsevier]

Abstract: Tamarind (Tamarindus indica L) seed polysaccharide (TSP) is of great important due to its various biological activities. The present investigation was carried out to compare extraction yield, morphological characteristics, average molecular weights and antioxidant activities of TSP from gamma- and electron beam (EB)-irradiated tamarind kernel powder. The tamarind kernel powder was irradiated with 0, 5 and 10kGy by gamma ray (GR) and electron beam, respectively. The extraction yield of TSP was increased significantly by EB and GR irradiation, but there was no significant difference between irradiation types. Morphological studies by scanning electron microscope showed that TSP from GR-irradiated tamarind seed had a fibrous structure, different from that of EB irradiated with a particle structures. The average molecular weight of TSP was decreased by the irradiation, and EB treatment degraded more severely than GR. Superoxide radical scavenging ability and total antioxidant capacity of EB-treated TSP showed higher than those of GR-treated TSP. [Copyright &y& Elsevier]

Abstract: β-glucans are structural cell wall polymers of many microorganisms and cereals which possess immunomodulatory properties and have been used in the food, cosmetic and medical industry. In our previous study, β-glucan was depolymerized by gamma irradiation and leads to improve the solubility and viscosity. This study was carried out to evaluate the functional properties, mainly immune-enhancing activities of low molecular weight β-glucan fragmented by gamma irradiation. The results showed that RAW 264.7 macrophage cell stimulation activities of irradiated β-glucan were higher than that of non-irradiated β-glucan. In addition, the oral administration of gamma-irradiated β-glucan significantly increased the proliferation and cytokine (IFN-γ and IL-2) release of spleen and Peyer''s patch cells compared with non-irradiated β-glucan. In conclusion, gamma irradiation could be used as an effective method for the production of depolymerized β-glucan improved functional property such as immunomodulatory activity. [Copyright &y& Elsevier]

Abstract: Doxorubicin (DOX) is a widely used anticancer agent, but exhibits some immunological toxicity to patients during chemotherapy. The present study was conducted to evaluate the effect of gamma irradiation on the immunological response and the inhibition activity on in vivo tumor mass of DOX. The results showed that DOX irradiated at 10 and 20kGy reduce the inhibition of mouse peritoneal macrophage proliferation and induce the release of cytokines (TNF-α and IL-6) when compared with non-irradiated DOX. The cytotoxicity against human breast (MCF-7), murine colon adenocarcinoma (Colon 26) and human monocytic (THP-1) tumor cell were not significantly different between non-irradiated and irradiated DOX (P<0.05). In vivo study on the tumor mass inhibition, gamma-irradiated DOX showed a considerable inhibition of tumor mass and this effect was statistically non-significant as compared with non-irradiated DOX. In conclusion, gamma irradiation could be regarded as a potential method for reducing the immunological toxicity of DOX. Further researches is needed to reveal the formation and activity of radiolysis products by gamma irradiation. [Copyright &y& Elsevier]

Abstract: Although the byproduct from Hizikia fusiformis industry had many nutrients, it is being wasted. In this study, the physiological activities of cooking drip extracts from H. fusiformis (CDHF) were determined to investigate the effect of a gamma and an electron beam irradiations. DPPH radical scavenging activity and tyrosinase and ACE inhibition effects of the gamma and electron beam irradiated CDHF extracts were increased with increasing irradiation dose. These were reasoned by the increase in the content of the total polyphenolic compound of CDHF by the gamma and electron beam irradiation. There were no differences for the radiation types. These results show that ionizing radiation could be used for enhancing the functional activity of CDHF which is a major by-product in Hizikia fusiformis processing, in various applications. [Copyright &y& Elsevier]

Abstract: Polysaccharides from seaweeds, fucoidan and laminarin, were irradiated with gamma rays, and their structural changes and anti-oxidative activities were investigated. The gamma irradiation decreased the average molecular weights of polysaccharides, and UV spectra of irradiated polysaccharides showed increases in the numbers of carboxyl and carbonyl groups and double bonds. DPPH radical scavenging ability and reducing power of the gamma irradiated polysaccharides were significantly higher than those non-irradiated. [Copyright &y& Elsevier]

Abstract: The present study was conducted to compare the efficacy of unirradiated β-glucan (UBG) and gamma irradiated β-glucan (GIBG) against acetaminophen (APAP) induced hepatotoxicity in mice. Mice of BALB/c strain were pretreated with UBG and GIBG (50mg/kg, p.o.) for 7 days and on the 8th day they received an overdose of APAP (500mg/kg, i.p.). Eight hours after the APAP injection, the levels of serum aminotransferase (AST) and alanine aminotransferase (ALT) were measured and liver, kidney and lung tissue were examined for morphological changes. A significant elevation (p <0.001) of the levels of AST and ALT was observed in mice toxicated with APAP. Histology data revealed severe liver centrilobular necrosis, portal vein damage with apparent toxicity in renal glomerulus and lung inflammation associated with edema. However, a significant inhibition (p <0.05) in the elevation of AST and ALT was observed in mice that received UBG and GIBG compared with APAP-treated mice. Histology examination revealed the non-statistical difference between the protective effects of GIBG and UBG against acetaminophen challenge. In conclusion, it was demonstrated that gamma irradiation induced no severe alteration in the protective activity of β-glucan against APAP-induced hepatotoxicity. [Copyright &y& Elsevier]

Abstract: Antioxidants quench oxidation by transferring hydrogen atoms to free radicals. In the present investigation, the effect of gamma irradiation on the natural antioxidants of irradiated cumin was studied. Cumin samples were purchased from retailers and then irradiated in a cobalt-60 irradiator to 0, 1, 3, 5 and 10kGy at ambient temperature. The effect of irradiation on the antioxidant properties of the cumin seed were investigated by evaluating the radical-scavenging effect on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, determination of ferric reducing antioxidant power (FRAP), total polyphenol content (TPC) and the antioxidant index by β-carotene/linoleic acid co-oxidation. Electron spin resonance (ESR) was performed to assess ionization of cumin seeds by gamma irradiation. Irradiation was found to nonsignificantly increase and/or maintain all antioxidant parameters, TPC and the ESR signal intensity was found to be increased in cumin seeds. [Copyright &y& Elsevier]

Abstract: In this study, the effects of an electron beam irradiation on the viscosity of a carboxymethylcellulose (CMC) solution were investigated. The viscosity of the CMC solution was decreased with an increase in the irradiation dose. Interestingly, the extent of the degradation of the CMC was found to decrease with an increase of the CMC concentration in the solution. The change of the average molar mass confirmed the decrease in the viscosity due to the degradation of the polymer. The energy of the electron beam also affected the degradation of the CMC. Lower degradation of the CMC was obtained with a decreasing electron beam energy due to its lower penetration. Addition of vitamin C as a radical scavenger to the solution and an irradiation at −70°C were shown to be moderately effective in preventing a decrease in the viscosity of the solution by irradiation. [Copyright &y& Elsevier]

Abstract: Hyaluronic acid (Hyaluronan, HA) was depolymerised by gamma irradiation and its structural changes and antioxidant activities were investigated. The structural changes of gamma irradiated HA were studied by gel-permeation chromatography (GPC), viscosity, pH, Hunter colour measurement, UV spectrophotometry, and FT-IR spectroscopy. The results demonstrated that gamma irradiation decreased molecular weight size, viscosity and pH of the hyaluronic acid and its colour turned to intense yellow. UV spectra of the irradiated HA showed a change at 265nm, which indicates the formation of double bonds. Differences in the height and shape of certain absorption bonds of FT-IR spectra in the range 1700–1750cm−1 were also observed, which is associated with the formation of carboxylic acid. From these structural changes of the HA, gamma irradiation may have a role in the formation of pyrancarboxylic acid rings. DPPH radical scavenging ability and the reducing power of gamma irradiated HA were significantly higher than that of non-irradiated HA. However, non-irradiated and irradiated HA did not show significant differences in the Rancimat test. [Copyright &y& Elsevier]

Abstract: The present study was attempted to evaluate the effects of gamma-irradiated doxorubicin (IRD) on spleen cell proliferation, cytokines release (IFN-γ and IL-2) and lung metastasis in mice. Gamma irradiation induced degradation of doxorubicin molecule and cytotoxicity on melanoma (B16BL6) and myoblast (H9c2) cell lines were determined by high performance liquid chromatography (HPLC) and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazole) assay, respectively. Non-irradiated doxorubicin (NIRD) was used as a control. The mice injected with NIRD (2mg/kg body weight for 5 days, 24h interval) showed a considerable decrease (P <0.05) in the body, spleen weight, proliferation and cytokine release (IL-2 and IFN-γ) as compared to control. However, a non-significant variation was observed in IRD treated mice compared with normal. Tumor bearing mice treated with NIRD and IRD (2mg/kg body weight, five doses at 48h interval) showed diverse results on spleen cell cytokine release, proliferation and metastasis. HPLC results revealed the formation of several trace level degradation (P <0.05) products of IRD. IRD displayed a non-significant variation of cytotoxicity on B16BL6 cells, and low percentage (P < 0.01) of cardiotoxicity on H9c2 cells as compared to NIRD. Altogether, this present study emphasis that gamma irradiation altered the property of doxorubicin. [Copyright &y& Elsevier]

Abstract: This study was carried out to evaluate the effect of gamma irradiation on the physical and structural properties of β-glucan. β-Glucan solution (10%, w/v) was exposed to a cobalt-60 source (10, 30, and 50kGy). Gel permeation chromatography data showed that the average molecular weight of irradiated β-glucan significantly decreased as the irradiation dose increased. In addition, gamma irradiation improved the solubility and decreased the viscosity of β-glucan by the radiolysis of the glycosidic bonds, and this effect was dependent upon the absorbed dose. Fourier transform infrared spectroscopy results showed that the functional groups of β-glucan were not significantly affected by gamma irradiation. Scanning electron microscopy results showed that the irradiated β-glucan was deformed into smaller granules. Therefore, gamma irradiation could be used in commercial processes as an effective method to resolve the physical problems involved in the use of β-glucan with high viscosity and low solubility. [Copyright &y& Elsevier]

Abstract: The present study was conducted to evaluate the effect of irradiation temperature on the shelf stability and quality of Kimchi during storage at 35°C for 30 days. Kimchi samples were N2-packaged and heated at 60°C and then gamma irradiated at 20kGy under various temperatures (room temperature, ice, dry ice, and liquid nitrogen). In the results of microbial, pH, and acidity analysis, combination treatment of heating and irradiation was able to sterilize microbes in Kimchi regardless of irradiation temperature. When Kimchi was irradiated under frozen temperatures, especially dry ice, the softening of texture and the deterioration of sensory quality of Kimchi were reduced. Also, ESR signal intensities were weakened due to the decrease of irradiation dose and temperature. [Copyright &y& Elsevier]

Abstract: The hepatoprotective efficacy of irradiated hyaluronic acid (HA) on acetaminophen (APAP) induced acute hepatotoxicity was investigated. BALB/c mice (4–6 weeks of age) were pretreated with unirradiated HA (UIHA), 5 and 50kGy gamma irradiated HA (GIHA) for 14 days and were dosed APAP (500mg/kgb.wt). After 9h of APAP dosing animals were euthanized. The degree of acute hepatotoxicity was measured by aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The expression of interferon-γ (IFN-γ) in serum and alpha-and mu-class of gluthathione-S-transferase (GSTs), CYP 2E1 class of cytochrome monooxygenase and glutathione (GSH) in liver were quantified. Histological evaluation was done by Hematoxiylin and Eiosin staining, Periodic acid schiffs staining, Manson trichrome staining and histological scorings were done. The degree of acute hepatotoxicity was markedly lower in UIHA and 5kGy than in 50kGy GIHA pretreated group and there was negligible difference between 5 and 50kGy GIHA pretreated group. The expression of interferon-γ (IFN-γ) was significantly (P <0.05) suppressed in 5 and 50kGy GIHA pretreated group. Histological scorings showed a significant protection of liver in UIHA and 5kGy GIHA pretreated mice. Expression of alpha class GSTs was significantly increased in 5 and 50kGy GIHA pretreated group. To conclude suppression of IFN-γ and increase in alpha-class GSTs expression may exert a protective role in acute hepatotoxicity of APAP and 5kGy GIHA showed comparable protective effect to that of UIHA. [Copyright &y& Elsevier]

Abstract: Cereal porridges have low energy and nutrient density because of its viscosity. The objective of the present study was to evaluate the effect of irradiation on the reduction of viscosity and on the increasing solid content of cereal porridge. Four cereals, wheat, rice, maize (the normal starchy type) and waxy rice, were used in this study. The porridge with 3000cP was individually prepared from cereal flour, gamma-irradiated at 20kGy and tested. Gamma irradiation of 20kGy was allowed that the high viscous and rigid cereal porridges turned into semi-liquid consistencies. The solid contents of all porridges could increase by irradiation, compared with non-irradiated ones. No significant differences of starch digestibility were observed in all cereal porridge samples. The results indicated that gamma irradiation might be helpful for improving energy density of cereal porridge with acceptable consistency. [Copyright &y& Elsevier]

Abstract: This study was aimed to evaluate the apoptotic effects of thiosulfinates purified from Allium tuberosum L. on PC-3 human prostate cancer cells, and to elucidate detailed apoptosis mechanisms. Thiosulfinates significantly decrease viable cell numbers in dose- and time-dependent manners by apoptotic cell death via DNA fragmentation, chromatin condensation, and an increased sub-G1 phase. Apoptosis induced by thiosulfinates is associated with the activation of initiator caspase-8 and -9, and the effector caspase-3. In this study, thiosulfinates stimulated Bid cleavage, indicating that the apoptotic action of caspase-8-mediated Bid cleavage leads to the activation of caspase-9. Thiosulfinates decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. Thiosulfinates also increased the expression of AIF, a caspase-independent mitochondrial apoptosis factor, in PC-3 cells. These results indicate that thiosulfinates from A. tuberosum L. inhibit cell proliferation and induce apoptosis in PC-3 cells, which may be mediated via both caspase-dependent and -independent pathways. [Copyright &y& Elsevier]

Abstract: This study was conducted to evaluate the combined effects of N2-packaging (N2), mild heating at 60°C (HT) and gamma irradiation of 20kGy (IR) on the shelf-stability and quality of Kimchi during storage at 35°C for 30 days. Total microbes including lactic acid bacteria were sterilized perfectly by the combination treatment of HT–IR or N2–HT–IR, and the acidity of Kimchi was not changed during storage. Irradiation softened textural property of Kimchi. However, combination of N2-packaging with heating and irradiation retarded this softening of Kimchi by high dose irradiation. Organoleptic qualities were improved by the combination treatment during the storage period. [Copyright &y& Elsevier]

Abstract: In this study, the effects of an irradiation on the viscosity of the carboxymethylcellulose (CMC) solution were investigated, and the methods to control the degradation of the CMC caused by an irradiation were developed. The viscosity of the CMC solution was decreased with an increase in the irradiation dose, but the extent of the degradation by an irradiation was found to decrease with an increase in the CMC concentration in the solution. The dependency of the irradiation sources showed that an electron beam radiation had degraded the CMC less severely than a gamma ray radiation. An addition of vitamin C as a radical scavenger to the solution was shown to be effective in preventing the decrease of the viscosity of the solution. Also, in the case of an irradiation at −70°C, the decrease of its viscosity was efficiently inhibited. The degradation of CMC in the solution was confirmed by the molecular weight distribution. [Copyright &y& Elsevier]

Abstract: House dust mites, Dermatophagoides farinae (DF) and Dermatophagoides pteronyssinus, are major allergens in the most common indoor allergen and are important risk factor for asthma. The modified antigen has been studied to treat allergic disorder. This study was carried out to measure possibility of modified allergen using gamma irradiation to treat allergy such as asthma. DF solutions (2mg/ml) as target allergen were irradiated with Co-60 at 50 and 100kGy. Conformational alternation of irradiated DF was observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Levels of anti-irradiated DF mouse IgGs (sub-isotypes) against intact DF were measured similar to that of anti-intact DF IgGs. The binding abilities of house dust mite-allergic patients’ IgE were reduced depending on radiation dose, and irradiation could inhibit the binding ability of patients’ IgE more than 40%. This study has shown that the binding ability of IgE was reduced by conformational alteration by irradiation and the irradiated DF had epitopes capable to induce immunogeniciy. [Copyright &y& Elsevier]

Abstract: The study was carried out to determine the effects of gamma irradiation on the volatile flavor components including essential oils, of Angelica gigas Nakai. The volatile organic compounds from non- and irradiated A. gigas Nakai at doses of 1, 3, 5, 10 and 20kGy were extracted by a simultaneous steam distillation and extraction (SDE) method and identified by GC/MS analysis. A total of 116 compounds were identified and quantified from non- and irradiated A. gigas Nakai. The major volatile compounds were identified 2,4,6-trimethyl heptane, α-pinene, camphene, α-limonene, β-eudesmol, α-murrolene and sphatulenol. Among these compounds, the amount of essential oils in non-irradiated sample were 77.13%, and the irradiated samples at doses of 1, 3, 5, 10 and 20kGy were 84.98%, 83.70%, 83.94%, 82.84% and 82.58%, respectively. Oxygenated terpenes such as β-eudesmol, α-eudesmol, and verbenone were increased after irradiation but did not correlate with the irradiation dose. The yields of active substances such as essential oil were increased after irradiation; however, the yields of essential oils and the irradiation dose were not correlated. Thus, the profile of composition volatiles of A. gigas Nakai did not change with irradiation. [Copyright &y& Elsevier]

Abstract: Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D 10-values were 0.22–0.27 and 0.76kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0logCFUg−1 onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10°C for 6h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula. [Copyright &y& Elsevier]

Abstract: Dried seasoned filefish (Thamnaconus modestus) was irradiated at 0–10kGy and the identification of irradiation treatment was investigated by analyzing the characteristics of thermoluminescence (TL), hydrocarbon (HC), and 2-alkylacyclobutanone (2-ACB). The TL (TL1), glow curve of the irradiated samples peaked at approximately 150°C with high intensity, but that of the non-irradiated samples peaked at about 300°C with little intensity, thus making it possible to discriminate between irradiated and non-irradiated samples. Moreover, TL ratio (TL1/TL2), through normalization steps, enhanced the reliability of the TL1 results. Six kinds of HCs and three kinds of 2-ACBs quantitatively determined for the samples linearly increased in proportion to irradiation doses. In particular, two HCs like 1-hexadecane and 1,7-hexadecadine, and three ACBs, such as 2-dodecylcyclobutanone, 2-(5′-tetradeceyl)cyclobutanone, and 2-tetradecylcyclobutanone, were identified only in the irradiated samples as radiation-induced markers. [Copyright &y& Elsevier]

Abstract: Microbial contamination was investigated using ice creams with a vanilla, chocolate, and strawberry flavor commercially available in Korea. Radiation sensitivity of the food-borne pathogens was also determined by an inoculation test. Food-borne pathogens used were Listeria ivanovii, Escherichia coli, and Salmonella typhimurium. Total aerobic bacteria, moulds and yeasts, and coliforms in the ice creams ranged from 2 to 3logCFU/g. Irradiation of 3kGy was enough to inactivate the total aerobic bacteria for the vanilla ice cream but that of 5kGy was needed for the chocolate or strawberry ice creams at a frozen condition (−20°C). To inactivate (>log6.5) the inoculated L. ivanovii, E. coli, and S. typhimurium into ice cream irradiation of 3, 1, and 0.1kGy was needed, respectively. The D 10 value of L. ivanovii and E. coli was calculated as 0.71–0.77 and 0.28–0.38kGy range for the ice cream with different flavors at −72°C, respectively. The D 10 value of S. typhimurium could not be calculated in this study because even 0.1kGy of irradiation reduced the number of S. typhimurium to undetected level. Results suggest that a low dose irradiation can improve the microbial quality and reduce the risk by the food-borne pathogens of ice cream, which has limited alternative sterilization methods due to the temperature characteristics of the products. [Copyright &y& Elsevier]