• Journal of Life Science
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• v.14 no.6 s.67
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• pp.925-930
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• 2004

Antioxidant activity and antimutagenic activities with and without simulated gastric digestion of hot water extracts from white and yellow onions were investigated as compared to BHT and ascorbic acid as control Contents of total phenol and flavonoid in hot water extract of yellow onion were higher than those of white one. The scavenging activity of hydrogen peroxide of both extracts were increased in direct proportion to added their concentration. Antioxidant activity and reducing power of the hot water extract were elevated through analysis of $\beta-carotene-linoleate$ system and were lower than those of BHT and ascorbic acid. Antimutagenic activity after simulated gastric digestion of hot water extract of white and yellow onions was observed against mutagen IG and MNNG on Salmonella typhimurium TA80 and TA100. Extract of yellow onion was higher in antimutagenic activity than that of white one. In conclusion, these results suggested that phenol and flavonoid in hot water extract from yellow and white onions may play an important role in the antioxidant and antimutagenic activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1538-1542
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• 2015

For development of premium sauce, fermented sauces containing ferment (with wheat flour and soybean) and extract(s) of Styela clava (Korean name: miduduk) tunic and/or mulberry leaves and/or onion were prepared, and their angiotensin converting enzyme (ACE) inhibitory and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities were evaluated. All sauces containing extract(s) showed increased ACE inhibitory and DPPH radical scavenging activities. Especially, sauces containing extracts of mulberry leaves and onion showed superior activities, with 26.92% and 40.66% relatively increased ACE inhibitory and DPPH radical scavenging activities, respectively, compared to control (no extract was added). These results suggest that extracts of mulberry leaves and onion could improve antihypertensive and antioxidant activities of fermented sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.565-569
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• 2011

Validation of quercetin as a marker compound in the standardization of Changnyeong onion extract developed for functional health food was attempted by analytical method. The specificity was satisfied with retention time and photo diode array (PDA) spectrum by analysis of quercetin using HPLC and comparison with standard compound. It showed a high linearity in the calibration curve as coefficient of correlation ($R^2$) of 0.9986, and the limit of detection (LOD) and limit of quantitation (LOQ) were 0.2 mg/L and 0.5 mg/L, respectively. Recovery rate test with quercetin concentration of 0.05, 0.075 and 0.1 mg/mL was revealed in the high range of 82.36~95.26%, 82.70~98.24% and 87.91~95.11%, respectively. The intra-day and inter-day precision in quercetin for Changnyeong onion extracts was 0.10~3.28% and 0.96~5.79%, respectively. Therefore, application of quercetin was validated in analytical method as a marker compound in Changnyeong onion extracts.

• Journal of Life Science
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• v.22 no.12
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• pp.1665-1671
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• 2012

This study was conducted to assess the removal of residual pesticides and to obtain high amounts of quercetin in onion peel extracts (OPEs) by 4 washing treatments. Washing is one of the standard processing steps in obtaining functional food ingredients from onion peel. After a first detergent wash (0.2% w/v) (DW) and hot air drying ($80^{\circ}C$, 24 hr) (B), 4 washing treatments were tested, including a second DW (C), ultrasonication ($50^{\circ}C$, 10 min) plus DW (D), 0.3% $H_2O_2$ (v/v) plus DW (E), and blanching ($95-97^{\circ}C$, 2 min) plus DW (F). This was followed by 60% (v/v) ethanol extraction and vacuum freeze drying of the OPE. The E treatment yielded 89.04% OPE and a quercetin content of 96.84% in the OPE compared with the B treatment, and had the highest efficiency of all treatments tested. The OPE was tested for the presence of 177 residual pesticides and three compounds were detected in all treatments: cyhalothirn, fluquinconazole and procymidone. Cyhalothirn and fluquinconazole levels were below the permitted levels for fresh onion, while procymidone was present in the high level range of 128.01~133.46 mg/kg in all samples. The E treatment was a better washing method than the others for removal of residual pesticides. It could reduce the level of residual pesticides without changing the functional properties of the OPE.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.23-27
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• 1999

To evaluate the quality of fish extracts with spicy vegetables (garlic, onion and ginger) in suppressing fishy oder, fish extracts of crucian carp, loach, bastard halibut and jacopever were processed at 100 $^{\circ}C$ for 6 hours, and their in vitro and in vivo protein qualities were determined . Protein and total lipid contents were closely related to the degree of discarding floated lipid on fish extracts and the kinds of added apicy vegetables . Boiling (10$0^{\circ}C$) , appeared to improve in vitro protein qualities slightly more than hydrocooking (11$0^{\circ}C$), but those with mild processing tended to result in better protein qualities than high temperature cooking (136-14$0^{\circ}C$). Spicy vegetables did not have remarkable effects on improving in vitro protein quality parameters. Fish extracts with 10% ginger were generally higher in in vitro protein quality than with the other vegetables . In spite of higher in vivo protein digestibility of fish extracts containing spicy vegetables processed under mild conditions(10$0^{\circ}C$), PERs of those extracts were not higher htan those of extranct processed at high temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.577-583
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• 2012

This study investigated the antioxidant activities, and antimicrobial activity $in$ $vitro$ of an 80% ethanol extract from garlic, daikon, leek, ginger, onion, and green onion, which are widely-used ingredients in Korean food that contain sulfur. The total polyphenol content in ginger and leek extracts showed a high value ($233.63{\pm}4.59$ and $220.98{\pm}10.56$ mg/g GAE) and onions, leeks, garlic, and daikon followed by with $69.07{\pm}1.42$, $68.83{\pm}2.11$, $19.41{\pm}0.40$, $19.05{\pm}03.32$ mg/g GAE, respectively. DPPH radical scavenging activity was highest with ginger extracts ($1.57{\pm}0.15$ mg/mL as $IC_{50}$) followed in order of decreasing activity by leeks, onions, daikon, green onions, and garlic. The results of ABTS radical scavenging activity and FRAP value showed higher antioxidant activity in extracts from ginger and leek. The order of vegetables with most to least prevalent ABTS radical scavenging activity was green onions, onions, garlic, and finally daikon. From greatest to least FRAP value, the relevant vegetables were green onions, onions, daikon, and garlic (p<0.05). Ginger extracts showed promise against seven strains of microbes: $Bacillus$ $cereus$, $Bacillus$ $subtillis$, $Staphylococcus$ $aureus$, $Lactobacillus$ $plantarum$, $Escherichia$ $coli$, $Salmonella$ $enterica$, and $Pseudomonas$ $aeruginosa$. Garlic extracts (5 mg/disc) showed strong antimicrobial activity against $B.$ $cereus$ (22.3 mm) and $E.$ $coli$ (24.3 mm). Extracts of both onion and green onion showed antimicrobial activity against only $E.$ $coli$ (12.7 and 10.3 mm) and $B.$ $cereus$ (12.0 and 12.5 mm) at 10 mg/disc, and the inhibition zone diameter from extracts of garlic and leeks were 18.0 mm and 10.4 mm vs. $L.$ $plantarum$ at 10 mg/disc. This study showed positive antioxidant activities for ginger and leeks, and positive antimicrobial activities for leeks and garlic. These sulfur-containing vegetables are widely used in Korean food. Leeks especially could serve as a functional food preservative.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.207-213
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• 1997

The effect of various vegetables commonly consumed by Koreans on the induction of glutathione S-trasferase(GST) activity in mice was assessd. The extract of vegetable dissolved in propylene glycol (5ml/kg body wt.) was administered to ICR female mice 6 to 8 weeks old via gavage during 5 days. The changes of body weight and liver weight of all treated groups were not significantly different compared with control group. Hepatic protein contents of trated groups compared with control group were not significantly different except BHT treated group. The induction of GST activity in liver cytosol of mice was the greatest with broccoli, followed by radish, wild green onion, turnip, and green onion. The induction of GST activity in liver cytosol increased up to 1.5 to 1.8-folds at a dose of 24 g fresh vegetable/mouse. The induction of combination between vegetables was the highest with the combination of broccoli and radish (1.83-fold), followed by that of broccoli and green onion (1.72-fold), and that of broccoli and turnip (1.50-fold).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.453-458
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• 1986

The present study was directed to investigate the antioxidative effects of onion and mustard powder extracts on fish oil. The oxidative changes of sardine oil with and without onion and mustard powder extract were estimated by measuring peroxide value (POV), thiobarbituric acid (TBA) value, weighing method, acid value (AV) and fatty acid composition, periodically. The results obtained are summarized as follows ; From view point of POV, fat soluble fraction of onion and mustard powder showed much inhibitory effect on the oxidation of sardine oil, marked induction period to be prolonged about 18 and 20 days, respectively. But the POV in fat soluble fraction of mustard powder increased remarkably in the early stage of storage, so it did not show inhibitory effect on the oxidation of sardine oil. In the TBA value of sardine oil during storage, the water soluble fraction of onion and mustard powder were more slowly increased than other fractions. The weighing change of sardine oil, contained in the water soluble fraction of mustard powder, was slower than other fractions, marking $0.5\%$ of weight gain during 30 day storage. On the other hand water and $80\%$ ethanol soluble fractions of onion were marked $2.3\%\;and\;5.8\%$ of weight gain during 30 day storage. In the oxidative degradation of docosahexaenoic acid, water soluble fractions of mustard powder and onion extracts showed the strongest inhiditory effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.298-305
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• 2016

Prior research has attempted to develop a method for fermentation of onion vinegar to satisfy customer quality standard. Onion wine (OW) and onion vinegar (OV) were produced by alcoholic and acetic fermentation of onion extracts (OE) using Saccharomyces cerevisiae and Acetobacter pasteurianus, and their taste compounds (non-volatile organic acids, non-protein N compounds, and free sugars) were determined. Main components of non-volatile organic acids were malic acid (50.1%) and citric acid (26.9%) in OE, whereas malic acid (28.1%), acetic acid (20.8%), lactic acid (20.1%), citric acid (13.3%), and succinic acid (12.0%) were detected in OW. Total concentrations of non-volatile organic acids in OV were 4,612.0 mg/100 g, which was 3.9 and 2.3 times higher than those of OE and OW, respectively. Non-volatile organic acids except malonic acid and acetic acid were reduced during acetic fermentation. Non-protein N compounds increased 4.23-fold ($41,526.8{\mu}g/100g$) during alcohol fermentation, and urea content was the highest of non-protein N compounds at $33,816{\mu}g/100g$. The reduced values in OV might be used as a nutritious element of Acetobacter pasteurianus. Free sugars (glucose, fructose, and sucrose) were detected in OE, whereas only fructose was absent in OW and OV.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.463-468
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• 1987

The present paper was investigated to elucidate the nitrite-scavenging ability of vegetable extracts. Vegetable extracts possessed the scavenging ability of nitrite. By fractionatioh of vegetable extracts,nitrite-scavenging ability of garlic (Allitum sativum for. Pekinense), chinese pepper (Zanthexylum schinifolium), onion (Allium cepa), welsh onion (Allium fistulosum) and ginger (Zingiber officinale) extracts were effective in the water-soluble fraction, but carrot (Daucus carota uar. sativa) in the methanol-soluble fraction. Nitrite-scavenging ability of vegetable extracts was also pH-dependent, highest at pH 1.2 and lowest at pH 6.0. Particularly, nitrite-scavenging abilities of water-soluble fractions obtained from garlic and chinese pepper were similar to that of L-ascorbic acid at pH 1.2. After vegetable extracts were treated with sodium borohydride, nitrite-scavenging ability was remarkably decreased at pH 1.2. It is assumed that reducing powers of vegetable extracts participated in their nitritescavenging abilities.