• Journal of the Korean Dietetic Association
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• v.4 no.1
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• pp.14-19
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• 1998

This study was designed to investigate the role of onion as a natural antioxidant. Onion was distinguished as yellow onion peel and onion flesh. Onion samples were extracted with 5 different kinds of solvents such as water, 70% ethanol, 99.9%ethanol, 99.9% methanol, and 96% butanol in order to select optimal extraction solvents, In this part of study linoleic acid was used s an model system for the purpose of determining the antioxidant activities. The optimal extraction rate of various solvents containing onion samples was determined by measuring extraction yield, electron donating ability(EDA), thiobarbituric acid(TBA), and thiocyanate, which are common methods for measuring activity. As a result 70% ethanol was shown as the most effective solvent.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.364-368
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• 2014

This study investigated the antioxidant activity of onion peels extracted from onion byproducts by hot water treatment. Hot water extraction of freeze dried onion peel powder was analyzed for total polyphenol content, 2,2'-diphenyl-1-picryllhydrazyl (DPPH), and 2,2'-azino-bis(3-ehtylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, reducing power, oxygen radical absorbance capacity (ORAC). Total polyphenol content was the highest (233.90 mg/g) in onion peel extract mix with ethanol (OPME-1). The DPPH radical scavenging activity ($IC_{50}$), reducing power, and ORAC obtainbed from onion peel extract mix with ethanol precipitation (OPMPE-1) were the highest at 1.15 mg/mL, 1.69 $A_{700}$, and $318,509{\mu}M\;TE/mL$, respectively. The ABTS radical scavenging activity was the highest at 432.78 mg amino acids (AA) eq/g in the OPM. The results of this study suggest that onion peel extracts have marked antioxidant activity, which can have significant health benefits.

• Korean Journal of Pharmacognosy
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• v.18 no.1
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• pp.34-40
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• 1987

Onion extracts were tested for effects on the growth and lactic acid production of Lactobacillus bulgaricus in the medium containing mercury. The media containing mercury were added with onion extracts and inoculated with the bacterium and then incubated at $39^{\circ}$ for four days. All of the onion extracts examined increased the growth and lactic acid production of the bacterium in the medium containing mercury. At the addition of the edible portion extract of onion to the medium containing 5 ppm, 10 ppm and 20 ppm mercury, the higher the concentration of the onion extract was added, the greater the increasing effect on the growth and lactic acid production. The brown peel extract of onion increased the growth and lactic acid production of the bacterium in the medium containing mercury at all concentrations. The higher the concentration of the extract added, the more effective the increasing effect. The onion solutions of edible portion and brown peel extracted at $90^{\circ}\;to\;100^{\circ}$ showed more desirable effects than those extracted at the room temperature. Among four kinds of the onion extracts, the brown peel solution extracted at $90^{\circ}\;to\;100^{\circ}$ was the most effective in increase of the growth and lactic acid production in the medium containing mercury.

• Journal of Life Science
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• v.22 no.11
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• pp.1477-1486
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• 2012

This study was performed to determine the effect of onion peel extract using 70% ethanol and 95% ethanol on its anti-oxidation activity, small intestine length, and intestinal villi of high-fat fed mice. Five percent of each onion peel extract using 70% and 95% ethanol showed significant decrease of E. coli and Listeria monocytogenes. Total phenolic contents of onion peel extracts using 70% and 95% ethanol were $166.89{\pm}0.03$ mg/g and $160.89{\pm}0.13$ mg/g, respectively. In anti-oxidation activity, DPPH radical scavenging activity and SOD-like activity of onion peel extracts were higher at 100 ug/ml concentration. The obese mice were fed high-fat diets supplemented by 1, 3, and 5% of the onion peel extracts using 70% and 95% ethanol for 4 weeks. Body weight, feed intake, feed efficiency, small intestine weight, length, villi's length, and number of bacteria in intestine were determined. Body weight of mice fed 5% of onion extracts using both 70% and 95% ethanol was significantly lower than that of control (p<0.05). However, feed intake was increased in mice fed 5% of onion extracts at both fermented ethanol levels. Small intestine weight and length of mice showed no significant change with supplementation of the onion peel extracts. However, length of small intestine villi was significantly longer than that of control. Total bacteria counts of Cl. Perfringenes and E. coli in small intestine of the mice were significantly reduced by supplementation of 5% of onion extract using ethanol, while lactic acid bacteria were increased. These results suggest that 5% of onion peel extracts using ethanol at either 70% or 95% concentration have potential to be used as an additive for body weight control and enhanced gut health; however, more research on its effectiveness is needed.

• Journal of the Korean Society of Costume
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• v.52 no.2
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• pp.91-101
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• 2002

In order to development of culture goods I made works with various color's silk fabrics dyed with water extract or methanol extract of plants. The Plants used for dyeing as dyeing material were indigo, safflower, amur cock tree, onion's Peel, citrus peel, mugwort, gromwell, sappan wood. Each of Plants were extracted by each of temperature and time. The mordants used for various color chanties are aluminium sulfate, cupric acetate mono hydrate, ferrous chloride. With fabrics of various color dyed like this I made works which give expression to an easy and natural image of the Korean nation of fabrics.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.406-413
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• 2011

This study was carried out to investigate antioxidative properties of various extracts and antibrowning effects of extracts in apple slices were investigated by ${\Delta}E$ value and PPO relative activity. Apples were cut into 1.5 cm thickness and they were dipped in 1% extract solutions(OW: water extracts of onion, OE: 80% EtOH extracts of onion, AW: water extracts of apple, AE: 80% EtOH extracts of apple, MW: water extracts of mandarin orange peel, ME: 80% EtOH extracts of mandarin orange peel) for 1 min. OW showed higher than the other treatments for total phenolic contents(94.35 mg/g), PPO inhibition(74.00%). And the highest DPPH free radical scavenging activity(40.27%) measured in ME. ${\Delta}E$ value of apple slices dipped in MW was 2.37 whereas ${\Delta}E$ value of apple slices dipped in AW was 12.12. These results suggest that onion and mandarin orange peel extracts should be a potential source for controlling browning during storage of apple slices.

• Journal of the Korean Society of Food Culture
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• v.30 no.1
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• pp.86-96
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• 2015

Onions contain antioxidant flavonoids and bioactive sulfur compounds. These substances are more abundant in the peel than in onion flesh. For this reason, whole onions including peels were added to soy milk to produce soy milk with whole onions (SWO), whereas peeled onions were added to soy milk to produce soy milk with peeled onions (SPO). The functional and antioxidant properties of these two kinds of soy milk were then analyzed and compared. Compared to control soy milk (CS) without onion powder, treated samples (to which freeze dried onion powder was added at 1.4, 1.6, 1.8, and 2.0%, respectively) showed significantly increased amounts of quercetin, isoflavone, and total phenol (p=0.05). The magnitude of the increase rose as the amount of added onion powder increased and when onion powder contained onion peels. With regards to antioxidant activity (DPPH and ABTS), SWO showed a greater value than SPO. The sensory evaluation scores of SWO and SPO were lower than CS for roughness and swallowing, as adding onion powder increased solid contents and viscosities. However, higher overall acceptability were obtained 1.8SPO and 1.8SWO.

• Journal of Biosystems Engineering
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• v.27 no.4
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• pp.311-316
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• 2002

This study was carried out to investigate the optimum operating conditions of the air injection type onion peeling device which could be attached to a prototype onion peeler. An onion, stem and root was cut and some vertical line was dug in 1 mm depth on the skin, was put on the two parallel rollers. The diameters of the rollers were 105 mm and the ratio of peripheral velocity was 3:2, and moved by a geared motor. Air from the nozzle with high pressure and velocity was jetted to the rotating onion on the revolving rollers, and then the skin of the onion was stripped. On the test, the rolling characteristics of the experimental materials were measured. The effective peeling conditions were, the number of digging line on the skin of the onion was 4, and the air jet pressure was above 392.3 kPa(4.0 kg/$\textrm{cm}^2$) when the peripheral velocity was at 2.4 m/s. On these conditions, time requirement to peel an onion was less than 2 sec.

• Nutrition Research and Practice
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• v.5 no.1
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• pp.28-33
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• 2011

Limited information from human studies indicates that dietary quercetin supplementation influences blood lipid profiles, glycemic response, and inflammatory status, collectively termed cardiometabolic risks. We tested the hypothesis that quercetin-rich supplementation, derived from onion peel extract, improves cardiometabolic risk components in healthy male smokers in a randomized, double blinded, placebo-controlled parallel design. Randomly assigned subjects were instructed to take either the placebo (n=43) or 100 mg quercetin capsules each day (n=49) for 10 weeks. Anthropometric parameters and blood pressure were measured, and blood lipids, glucose, interleukin-6, and soluble vascular cell adhesion molecule-1 (sVCAM-1) were determined at baseline and after 10 weeks of quercetin supplementation. Quercetin-rich supplementation significantly reduced serum concentrations of total cholesterol (P<0.05) and LDL-cholesterol (P<0.01), whereas these effects were not shown in the placebo group. Furthermore, significant increases were observed in serum concentrations of HDL-cholesterol both in the placebo (P<0.005) and quercetin-rich supplementation group (P<0.001); however, changes in HDL-cholesterol were significantly greater in subjects receiving quercetin-rich supplementation than the placebo. Both systolic (P<0.05) and diastolic blood pressure (P<0.01) decreased significantly in the quercetin-rich supplementation group. Glucose concentrations decreased significantly after 10 weeks of quercetin-rich supplementation (P<0.05). In contrast, no effects of quercetin-rich supplementation were observed for the inflammatory markers-IL-6 and sVCAM-1. Daily quercetin-rich supplementation from onion peel extract improved blood lipid profiles, glucose, and blood pressure, suggesting a beneficial role for quercetin as a preventive measure against cardiovascular risk.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.59-63
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• 2003

This study aims at developing of textile design expressed not only Korean natural image but also modern sensibility using fabrics dyed by tie dyeing with various natural dyes. And it attempts to practicality of high value-added goods revived traditional beauty. With the aqueous extract of various natural dyes, i.e., indigo, amur cock tree, onion's peel, citrus peel, mugwort, gromwell, sappan wood silk fabrics dyed by tie dyeing. Also various color changes were examined by mordants, i.e., aluminium sulfate, cupric acetate mono hydrate, ferrous chloride. With these fabrics, I made works using the techniques of applique, mola, fabric's connection and weaving. I think the developed textile design gave expression to natural image of Korean nation.