• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.582-589
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• 1991

The effects of types of soybean sauceI(SS) and additives for soybean sauce(AS)on the antioxidative activity was studied. The values of peroxides(POV) and thiobarbituric acid (TBA) were monitored under the oxidation systems of linoleic acid or ground cooked meat. Among 10 types of SS including Korean treditional SS, Koran M company's raw SS, Korean koikuchi, Korean acid hydorlyzed SS, Korean mixed SS, Korean decolorized SS, Japanese tamari, koikuchi, usuguchi, and Japanese white SS, three SS types of Japaness tammari, koikuchi and Koran raw SS were found to have the most strong antioxiative activity. However, various as such as monosodium glutamate, caramel, fructose syrup, malt syrup and paraoxybenzoic acid (POBA) were appeared to accerlerate oxidation. Possibly an important antioxidative cahracteristics was due to its higher concentration of nitrogen and melanoidin.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.744-750
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• 2006

An experiment was carried out to evaluate the effects of substituted conjugated linoleic acid (CLA) for fat on qualities, lipid oxidation and residual nitrite contents in emulsion-type sausage (ETS) after different periods of storage. The control sausage contained 20% fat, however, the substituted CLA for fat sausages contained 17.5% fat+2.5% CLA, 15% fat+5% CLA, 12.5% fat+7.5% CLA and 10% fat+10% CLA, respectively. CLA concentration was significantly increased (p<0.05) by substitution of CLA sources for fat, and storage did not affect the CLA concentration. TBARS were significantly increased with the increasing of storage time in all treatments (p<0.05). Significantly higher $L^*$ values were observed in the 10% CLA treatment compared to other treatments during storage. Moreover, $a^*$ values in CLA treatments significantly (p<0.05) increased compared to the control. Again, $b^*$ values were significantly (p<0.05) higher in CLA treatments than those of the control during storage. The concentration of residual nitrite in ETS was significantly (p<0.05) different between the treatments during storage and the results were in the following order: control >2.5% CLA>5% CLA and 7.5% CLA>10% CLA. Overall acceptability of CLA treatments was significantly (p<0.05) lower than the control during storage, whereas no significant differences were found in overall acceptability between the treatments after 28 days of storage.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.185-192
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• 2007

The different parts of 8 edible and medicinal ferns were extracted with 80% ethanol and the bioactive substances and antioxidant activities were investigated. Total polyphenol content was highest in Cyrtomium fortunei rhizome ($57.32mg{\cdot}g^{-1}$) and followed by C. fortunei root, Pyrrosia lingua aerial part and Onoclea sensibilis var. interrupta aerial part. Total flavonoid contents ranged from 1.95 (Onoclea sensibilis var. interrupta rhizome) to $27.51mg{\cdot}g^{-1}$ (O. sensibilis var. interrupta aerial part). Among the samples tested, C. fortunei root and rhizome were found to be most effective in both DPPH and ABTS radical scavenging assay. Except in Selaginella tamariscina underground part and Osmunda japonica aerial part, most of the tested samples showed strong potential (above 87%) in inhibition rate on linoleic acid oxidation.

• Toxicological Research
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• v.27 no.1
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• pp.1-6
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• 2011

Lipid peroxidation is a free radical oxidation of polyunsaturated fatty acids such as linoleic acid or arachidonic acid. This process has been related with various pathologies and disease status mainly because of the oxidation products formed during the process. The oxidation products include reactive aldehydes such as malondialdehyde and 4-hydroxynonenal. These reactive aldehydes can form adducts with DNAs and proteins, leading to the alterations in their functions to cause various diseases. This review will provide a short summary on the implication of lipid peroxidation on cancer, atherosclerosis, and neurodegeneration as well as chemical and biochemical mechanisms by which these adducts affect the pathological conditions. In addition, select examples will be presented where antioxidants were used to counteract oxidative damage caused by lipid peroxidation. At the end, isoprostanes are discussed as a gold standard for the assessment of oxidative damages.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.151-156
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• 2002

Antioxidant activity or green tea extracts (GTE) was evaluated in soybean oil (SBO), rice bran oil (RBO) and winterized rice bran oil (WRBO) stored at 63$^{\circ}C$ for 36 days. Lipid oxidation of the oils was determined using the active oxygen method (AOM), peroxide value (POV), change in unsaturated free fatty acid concentrations and by sensory evaluation. SBO had a higher concentration of the polyunsaturated fatty acids, linoleic and linolenic acid than RBO and WRBO. WRBO and RBO were more stable against lipid oxidation than SBO. Addition of GTE (200 ppm) to the stored oils, increased the induction period (IP) in AOM, reduced the increase in POV, and lessened the change in unsaturated fatty acids. Furthermore, GTE prevented the development of rancid flavors resulting from storage, all of which demonstrate the protective antioxidative activity of GTE. However, oil color became darker in the GTE treated oils. The antioxidant protection of GTE was most effective in RBO.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.62-68
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• 2000

Effects of conjugated linoleic acid (CLA) on physico-chemical properties of cooked ground pork patty were investigated for 11 days at $4^{\circ}C$. Pork patties containing 0, 1, 2, and 3% CLA were cooked at $90^{\circ}C$ for 30 min. The contents of crude protein and fat did not change whereas the content of ash and water decreased as the level of CLA enhanced. Lipid oxidation as measured by thiobarbituric reactive substances of patty was inhibited by addition of CLA. CLA treatment also reduced nitrite and cholesterol content and changed fatty acid composition. Consequently, given these positive effects of CLA, it may be assumed that CLA could be used as a fat additive for value-added pork patty.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.899-903
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• 2005

One of the most important volatile aroma compounds responsible for mushroom flavor is 1-octen-3-ol. To meet the demand for natural mushroom flavor, a study was needed for the production of natural chiral specific (-)-1-octen-3-ol that has higher flavor intensity than synthetic chiral mixtures of (+), and (-)-1-octen-3-ol. The biosynthesis of (-)-1-octen-3-ol was achieved by an aerobic oxidation using lipoxygenase (LOX) and hydroperoxide lyase (HPOL) isolated from commercially available mushrooms in Korean market. Safflower oil from Uiseong, Gyeongsangbuk-do, that contains $\geq75\%$ of linoleic acid, was hydrolyzed using lipase. The recovered linoleic acid was biotransformed to stereo-specific 10-hydroperoxy linoleic acid by LOX. 10- hydroperoxy linoleic acid was further cleaved to (-)-1-octen-3-ol by HPOL. A commercial bioprocess for the production of (-)-1-octen-3-ol was developed using a 5-liter jar fermenter with fruiting bodies of Agaricus bisporus harvested from Buyeo, Chungcheongnam-do. The maximum production of (-)-1-octen-3-o1 was achieved at $4^{\circ}C$, pH 6.5 and 800 rpm yielding 748 mg/kg of mushroom.

• Journal of the Korean Society of Food Science and Nutrition
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• v.10 no.1
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• pp.17-25
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• 1981

The purpose of this study was to determine effects of thermal oxidation according to heating time and temperature, using sunflower oil from seed grown in Korea. To investigate these effects, the lipid components, fatty acid compositions, and chemical characteristics of crude oil from sunflower seed were determined. The content of nonpolar and polar in total lipids was 94.1% and 5.9%, respectively. The fatty acid compositions in the total lipids showed 6.21% palmitic, 4.50% stearic, 59.84% oleci and 29.48% linoleic acid. The concent of linoleic acid decreased during heating. However, the concent of oleic, palmitic and stearic acid increased during heating. The components of neutral lipid were found 6 fractions, including triglyceride, diglyceride and free fatty acid. The content of triglyceride decreased but diglyceride and monoglyceride increased during heating. The content of free fatty acid increased during the continuous heating period for 32 hours at $100^{\circ}C$, whereas decreased in 16 hours at $180^{\circ}C$. Iodine value decreased during heating, and peroxide value increased during the continuous heating period for 32 hours at $100^{\circ}C$, whereas decreased in 16 hours at $180^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.732-736
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• 2000

The purpose of this study was to investigate the extraction method of phenolic compounds and antioxidant activities of the aerial part of Epimedium koreanum NAKAI (EKN). The antioxidant activities of EKN were tested with by hydrogen donating ability, inhibition of lipid peroxidation, and inhibition of LDL oxidation. The most suitable conditions for the extraction of phenolic compounds from EKN were to use 60% ethanol by 3 times, and the yield of extract (dry basis) was 22%. In the extraction efficiency of phenolic compounds, 60% ethanol as extracting solvent was superior to water. Sixty% ethanol extract of EKN was found to have an ability of hydrogen donating to DPPH. MDA determination showed the 95% inhibitory effect against linoleic acid oxidation by the addition of 700 ppm EKN extract. Also, about 70% of LDL oxidation was inhibited by the addition of 500 ppm.

• 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.