• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.781-785
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• 1999

Ferrisilicates with MFI type structure were hydrothermally synthesized. The structural environments of iron in the ferrisilicates were characterized by XRD, SEM, IR, EPR, and ammonia-TPD. It has been shown that pH of the final gel mixture during the synthesis affects the crystal size, morphology, chemical composition and catalyticactivity. The results of the lattice parameters, IR, and EPR indicate the existence of a framework iron and the content of framework iron depends on pH of the synthesis gel. Finally, the catalytic activity of these zeolites was examined for the cyclohexane oxidation to cyclohexanol and cyclohexanone in the liquid phase. The conversion of this reaction was increased with increasing iron content of the framework lattice positions.

• Journal of the Korean Applied Science and Technology
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• v.40 no.4
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• pp.699-709
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• 2023

This study is to establish optimizing condition of alcohol fermentation in vinegar production with aronia, to confirm whether this can be industrially used, and to compare and analyze a change in anti-oxidative activity and quality characteristic according to alcohol fermentation of aronia. The optimized conditions for alcohol fermentation were as follows: Saccharomyces cerevisiae 5645 of yeast strain, a 5% inoculum size, aronia juice with a brix value of 14, and a glucose content of 7%. As a result to conduct scale up with optimizing conditions of alcohol fermentation of aronia, 8 days (192 hrs) of total alcohol fermentation time and 7.4% of the final alcohol content. The harvest volume accounted for approximately 90.2% with a loss of about 2.8%. As a result of antioxidant test, anti-oxidative activity of alcohol fermented liquor is lower than anti-oxidative activity of aronia extract, because of the decrease of antioxidant by oxidation of the fermentation process. However, the decrease of tannin by the fermentation process reduces acerbity of aronia, so increases overall preference

• Food Science of Animal Resources
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• v.36 no.3
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• pp.359-368
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• 2016

The brown soybean extract (BE, extracted by distilled water, 50%, 75%, and 95% ethanol) were analyzed for their total phenol, flavonoid, anthocyanin content, and DPPH radical-scavenging activity to determine antioxidant activities. Brown soybean extract with 75% ethanol showed significantly higher DPPH radical scavenging activity, total phenol and anthocyanin content compared to the other treatments (p<0.05). Then, brown soybean extract with 75% ethanol was applied to pork patties at different concentration (0.05%, 0.1%, and 0.2%) and lipid oxidation was evaluated during 15 d of refrigerated storage. Addition of BE significantly increased redness and pH values, respectively (p<0.05). Moreover, TBARS value of pork patties decreased significantly (p<0.05) as BE concentration increased. In sensory evaluation, pork patties with 0.1% BE had significantly higher score than other treatments in flavor and overall acceptability (p<0.05). Consequently, these results indicate that 0.1% BE could be an effective natural antioxidant to inhibit lipid oxidation in pork patties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.155-159
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• 2002

Effect of the egg yolky from laying hens intubated, p.o., astaxanthin (designated AEY) on the oxidation of mouse liver microtome was investigated using female ICR mouse (6~7 weeks of age). Mice were adapted in a temperature- and humidity-controlled house for one week and randomly divided into 7 treatment groups (10 mice/cage/treatment). Mice were intubated p.o., AEY (50, 100 and 150 mg) or control egg yolk (CEY, 150 mg) every week for 3 weeks. BHT (5 mg) and e -tocopherol (50 mg) were fed to mice as positive control. At week 4, the liver microsome was prepared from sacrificed mice. Protein content of mouse liver microsome with AEY treatment was relatively higher than that with CEY treatment. AEY treatment remarkably lowered the content of unsaturated fatty acids including oleic acid and linoleic acid, but raised that of the saturated fatty acids including stearic acid. AEY group showed relatively higher antioxidative activity than CEY, when used Asc/F $e^{+2}$ or NADPH/F $e^{+2}$ as oxidant. Antioxidative activity of AEY was more effective than $\alpha$-tocopherol, but less effective than BHT.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.628-635
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• 2009

Autoxidative stability of wheat bran and germ oil extracted from Keumkang wheat (WBG-K) or Dark Northern Spring wheat (WBG-DNS) at $50^{\circ}C$ in the dark was compared by peroxide values (POV) and fatty acid composition by gas chromatography. Changes of minor compounds were monitored by HPLC. WBG-K showed significantly higher linoleic but lower oleic acid content than WBG-DNS. WBG-DNS contained more phospholipids but less tocopherols and carotenoids than WBG-K. POV of oils was increased during storage, with no significant difference in the oxidation rates between two oils. Tocopherols, carotenoids, and phospholipids in both oils were degraded during the autoxidation. Total phospholipids content showed the highest correlation with the degree of oxidation in WBG oils. The results clearly showed that both fatty acid composition and contents of tocopherols, carotenoids, and phospholipids co-affected the autoxidation of WBG oil.

• BMB Reports
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• v.28 no.5
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• pp.420-426
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• 1995

This study was conducted to compare the effects of n-6 linoleic acid and n-3 linolenic acid on lipid peroxidation and the activities of enzymes defending against oxidation, which are involved in the tumor promotion, and histolOgical changes of hepatocarcinogen treated rat liver. In this study, weanling male Sprague-Dawley rats were fed one of three diets, containing 15% (w/w) of beef fat (BF), com oil (CO) or perilla oil (PO), for 11 weeks. During the 3rd week, experimental groups were injected with 2-AAF (50 mg/kg of BW) intraperitoneally 3 times. Findings show that the com oil diet group has greater liver MDA content than the beef fat and perilla oil diet groups. Also, it is observed that the perilla oil diet group has lower MDA content than beef fat and com oil diet groups, even though perilla oil is more desaturated than beef fat and com oil. In terms of activity, mixed-function oxidase activity is not Significantly affected by the different dietary fats and 2-AAF treatment. GSH-peroxidase, GSH-reductase and GSH-Stransferase activities are significantly higher in the CO+AAF group than those of the other groups. GST and GSH-Px are activated by 2-AAF treatment in the com oil diet group only. The hepatocytes of the BF+AAF group were the most severely degenerated, the second was the CO+AAF group and the least was the PO+AAF group. It was also found that dietary com oil increased lipid peroxidation and activated defense enzymes against oxidation in liver, but dietary perilla oil did not, or supressed defense enzymes. Therefore it is concluded that dietary n-3 linolenic acid in perilla oil inhibits lipid peroxidation and carcinoenesis in rat liver following 2-AAF treatment.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.704-710
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• 1988

This study was, firstly, to investigate water holding capacity in terms of variation of moisture sorption isotherms of seasoned squid treated with sodium lactate, glycerol, propylene glycol, sorbitol, mannitol, sodium benzoate, potassium sorbate and calcium propionate, and secondly, the effect of humectant treatments on storage stability was studied. The criteria for storage stability was based on three quality factors, namely, lipid oxiations, color development by non-enzymatic browning reactions and lipid oxidation, and mold growth. The effect of humectants on equilibrium moisture content was in the following increasing order; mannitol < sorbitol < sodium lactate < propylene glycol < glycerol. The experimental data indicated that sodium lactate has, in practice, potentially positive effect on processing of seasoned squid. During the storage period of 60 days, TBA values increased in all samples tested as humectants concentrations increased up to 10%. However, in the range of 1-7% sodium lactate treatment, the degree of lipid oxidation, browning reactions and mild growth were not high enough to affect the quality of seasoned squid, when compared with conventionally manufactured ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.96-100
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• 1993

The changes in the concentration of toropherol and carotenoid in pinenut oil at various stage of refining are studied during autoxidation. The oxidative stability of pinenut oil decreased with the refining degree increased. The tocopheol content of total crude oil was 55.51mg/100g oil and $\alpha$, ${\gamma}$and $\beta$-tocopherol in the crude oil were 25.48mg, 23.94mg and 6.99mg in order, respectively. The amount of $\delta$-tocopherol was trace. The concentrations of $\alpha$, ${\gamma}$ and $\beta$-tocopherol in pinenut oil after degumming or alkaline refining were 23. 85mg, 19.79mg and 6.12mg or 24.08mg, 24.04mg and 5.33mg, respectively. The content of f-carotene was 0.63% of total unsaponifiable materials and that of lycopene was trace. The concentrations of carotenoids and toropherols in pinenut oil decreased while autoxidation progressed. Degrees of destruction of carotenoids and toropherols. were significant at first stage of oxidation. Decrease in $\alpha$-toropherol was found to be faster than that in $\alpha$, ${\gamma}$-tocopherol during oxidation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.3
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• pp.224-231
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• 2012

We investigated the effects of various washing methods on the quality of semi-dried Pacific saury Cololabis saira, known in Korea as Guamegi. We immersed samples for 5 min in seawater, tap water, chlorinated water (100 mg/kg), ammonia water (100 mg/kg), citric acid (0.1 M), butylated hydroxyanisole (BHA, 0.2 g/kg), or sesame oil (5 g/100 g), and then dried them in the sun for 3 days. The moisture and crude lipid contents after drying were 26.62-32.49 g/100 g and 26.40-33.01 g/100 g, respectively. The moisture content significantly decreased while the crude lipid content increased during drying. The different washing methods did not have a significant effect on the acidity, peroxide values, or levels of thiobarbituric acid or biogenic amine in Guamegi. The lightness of Guamegi during drying significantly decreased, but this decrease was not significantly different among washing methods. The degree of acceptance in a sensory evaluation was higher for Guamegi treated with sesame oil. Our results suggest that these washing methods should not be used to inhibit lipid oxidation, biogenic amine formation, or color changes in semi-dried Pacific saury, because effective components are extracted by the lipids during drying.

• Food Science of Animal Resources
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• v.35 no.3
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• pp.330-338
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• 2015

The effects of dietary supplementation of processed sulfur in pigs according to the level provided during the fattening phase were examined. The pigs were divided into three groups: control (CON), non-sulfur fed pigs; T1, 0.1% processed sulfur fed pigs; T2, 0.3% processed sulfur fed pigs. Physicochemical and sensory properties, as well as meat quality and oxidative stability of the Longissimus dorsi muscle were investigated. The feeding of processed sulfur did not affect moisture and protein contents (p>0.05). However, the crude fat content of T2 was significantly decreased compared to CON (p<0.05), while the pH value of T2 was significantly higher than those of both CON and T1 (p<0.05). Cooking loss and expressible drip of T2 were also significantly lower than that of CON (p<0.05). The redness of meat from T1 was significantly higher than both CON and T2 (p<0.01). During storage, lipid oxidation of the meat from sulfur fed pigs (T1 and T2) was inhibited compared to CON. Examination of omega-3 polyunsaturated fatty acids revealed T2 to have significantly higher content than CON (p<0.05). In the sensory test, the juiciness and overall acceptability of T2 recorded higher scores than CON. This study demonstrated that meat from 0.3% processed sulfur fed pigs had improved nutrition and quality, with extended shelf-life.