• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.628-633
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• 2012

This study investigated the washing efficiency of electrolyzed water for the removal of microorganisms and pesticide residues from Chinese cabbage. Initial total bacteria and coliform counts were 6.64 and 3.56 log cfu/g respectively. After washing, total bacteria count of tap water (TW) were 5.97 log cfu/g and low alkaline electrolyzed water (LAlEW) and strong acidic electrolyzed water (SAcEW) were 1.63-4.67 log cfu/g. Especially SAcEW-100 was found to the most effective method of washing the cabbages. After washing, the coliform count was dramatically reduced. The removal rate of pesticide residues by NaClO treatment (36.93-50.13%) was greater than that of TW treatment (32.28-38.46%). The removal rate of LAlEW-100 and SAcEW-100 was 63.79 and 78.30% respectively, and was higher than those of TW and NaClO treatments. The vitamin C content of the Chinese cabbages after all treatments did not differ significantly. Consequentially, the electrolyzed water was found to be effective to remove bacteria and pesticide residues from Chinese cabbage without affecting quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.460-465
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• 2005

Water and ethanol extracts from Rue were prepared, and their growth inhibiting activity against Helicobacter pylori and other biological activities were examined. Total phenolic compounds in the water and ethanol extracts were present at the concentration of 16.39 mg/g, and 17.07 mg/g, respectively. At the concentration of $200\;{\mu}g/mL$ of phenolic compounds concentration, water extract produced 12 mm inhibition zone while ethanol extract produced 13 mm. The ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)] radical decolorization and antioxidant protection factor (PF) were determined for extracts from Rue. Water extracts showed $96\%$ inhibition rate on ABTS, but ethanol extracts showed higher PF (1.2) than water extracts (0.8). Water extracts had higher electron donation ability on DPPH than ethanol extracts. But ethanol extracts had higher ACE (angiotensin converting enzyme) and xanthine oxidase inhibitory activities than water extracts. Rosemarinic acid and quercetin were the most abundant phenolic compounds as analyzed by HPLC.

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.114-122
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• 2017

N-nitrosamines can be produced in the process of heating, processing, storage and packaging. Migration specifications for N-nitrosamines exist only for rubber baby bottle nipples, which are regulated by the Ministry of Food and Drug Safety (MFDS). There is no regulation for other food contact substances (FCS) and studies on N-nitrosamines migration from FCS are rather limited. A pilot study showed an increase in N-nitrosamines contents when cooking instant noodles. Thus, the migration from the packaging was suspected and it was necessary to monitor the migration of N-nitrosamines from food packaging materials and to examine the change in N-nitrosamines contents when cooking instant foods. Three N-nitrosamines, NDMA (N-nitrosodimethtlamine), NDEA (N-nitrosodiethylamine), NDBA (N-nitrosodibutylamine), were analyzed in migration test solutions from plastics such as polyethylene, polypropylene and polystyrene, papers and aluminium containers. In all test solutions, N-nitrosamines were detected less than method quantitation limits (MQLs). Food samples were also investigated to ensure that there is no effect from food contact substances when cooking instant foods. In retort sauces such as curry, black soybean sauce and tomato sauce, NDMA concentration was ranged from 0.54 to $3.81{\mu}g/kg$, but there were no significant differences between unheated and heated samples. However, the NDMA contents were significantly increased in most of the instant noodle samples tested when cooked (p < 0.05). No effects from the food contact substances or cooking water was observed. Only when the seasoning powder and noodles were cooked together was NDMA detected. Individual components (noodle, seasoning powder or dried vegetable) or other combinations such as noodles and dried vegetables did not generate N-nitrosamines. Therefore, it is speculated that NDMA may be formed from the precursors in noodles and seasoning powders when they are solubilized in a medium of water.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1415-1420
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• 2009

The aim of the present study was to examine the prevalence of thermophilic Campylobacter spp. (Campylobacter jejuni and Campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in Malaysia. C. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1 % and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm A and farm B, respectively, when using the MPN-PCR method. Campylobacter spp. was not found in any of the irrigation water samples tested. Therefore, the present results indicate that the aged manure used by farm A was more contaminated than the composted manure used by farm B. Mostly, the leafy and root vegetables were contaminated. C. coli was not detected in any of the samples tested in the current study. Both farms tested in this study were found to be contaminated by campylobacters, thereby posing a potential risk for raw vegetable consumption in Malaysia. The present results also provide baseline data on Campylobacter contamination at the farm level.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.265-270
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• 2008

This study examined the effects of treating green tea leaves with ozonated water by evaluating pesticide residue levels and catechin content. The pesticide residue levels of tea leaves treated with carbendazim, captain, diazinon, fenthim, dichlorvos, and chlorpyrifos ranged from 43.2 to 48.2 ppm. For leaves treated by soaking or watering with tap water, or with 0.25 ppm of ozone water for 30 min. Pesticide residue levels were reduced by 24.0-30.2%, 30.3-33.6%, 52.4-70.5%, and 65.5-80.2%, respectively. No major differences in catechin content were observed in the leaves according to the soaking and rinsing treatments using ozonated or tap water.

• Food Science and Preservation
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• v.6 no.1
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• pp.104-109
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• 1999

Ethyl acetate, methanol, water extract and their fractions from chestnut flower(Castancea crenata) were tested for antimicrobial activities. Yields of prebloomed chestnut flower extracts were 13.84, 12.90 and 1.82% in methanol, water and ethyl acetate, and those of the postbloomed were 13.12, 11.75 and 1.18%, respectively. Methanol extract from the chestnut flower was fractionated by solvents using hexane, chloroform, ethyl acetate, n-butanol and water, yields of those fractions were 0.16, 0.08, 1.94, 4.75 and 6.91% in the prebloomed, and were 0.90, 0.13, 1.40, 3.42 and 7.18% in the postbloomed. In the solvent extracts of water, ethyl acetate and methanol, methanol extract showed the most effective antimicrobial activity, antimicrobial activity of ethyl acetate fraction of methanol extract was stronger than others. Minimum inhibitory concentration of ethyl acetate fractions from the prebloomed showed 100, 140, 100 and 90ppm against Staphylococcus aureus, Streptococcus mutans, Echerichia coli and Salmonella typhimurium, in fractions from the postbloomed were 140, 140, 100 and 150ppm, respectively. Growth of all the strains was completely inhibited to 30 hours in a 150ppm concentration. E. coli sells treated with ethyl acetate fraction was collapsed severely.

• Korean journal of food and cookery science
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• v.16 no.5
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• pp.390-393
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• 2000

Desmutagenic effects of water-soluble and ethanol-soluble extracts of dried green tea toward the mutagenicity of 4-nitroquinoline-N-oxide(4-NQO) and 3-Amino-1,4-dimethyl-5H-pyrido［4,3-b］indole(Trp-P-1) in streptomycin-dependent SD510 strains of Salmonella typhimurium TA98 were investigated. Inhibition effects toward the mutagenicity of 4-NQO and Trp-P-1 of water-soluble and ethanol-soluble extracts from green tea were high as increase of concentration of extracts. Desmutagenic effects toward 4-NQO of water-soluble and ethanol-soluble extracts from green tea harvested in May and August were up to 93% in 1,000 $\mu\textrm{g}$ of extract/plate. Desmutagenic effects toward Trp-P-1 of ethanol-soluble extracts from green tea were 53.3∼92.1%, but the effects of water-soluble extracts decreased as increase of concentration of extracts.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.236-241
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• 2011

Allium victorialis L. (A. victorialis) is a very popular vegetable in Korea. The most commonly used parts of this vegetable are the bulbs and young leaves. To determine if the mature leaves have any beneficial properties, we investigated antioxidant, anti-${\alpha}$-glucosidase, anti-inflammatory, and anticancer activities of water and ethanol extracts from A. victorialis. Antioxidant activity was evaluated by measuring total phenolic content, DPPH and superoxide radicals scavenging activities. The water extract from A. victorialis ($W{\cdot}A$. victorialis) exhibited higher antioxidant ability than the ethanol extract ($E{\cdot}A$. victorialis). Moreover, the water extract showed strong inhibitory effect on ${\alpha}$-glucosidase. On the other hand, the ethanol extract had greater anti-inflammatory activity on murine macrophage cells (RAW 264.7) and greater anticancer activities against human colon cancer cells (HT-29). These results suggest that mature leaves from E·A. victorialis may have health-enhancing effects.

• The Korea Journal of Herbology
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• v.23 no.3
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• pp.41-51
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• 2008

Objectives : This study was conducted to evaluate the antioxidative and anticancer activity of extracts from Scutellaria baicalensis, Zizyphus jujuba and Atractylodes macrocephala. Methods : Three kinds of medicinal herbs were extracted with distilled water and 70% ethanol, and the extracts were tested for their antioxidant activity and growth inhibition activity against cancer cells. Results : Electron donating abilities (EDA) of the water and ethanol extract from Zizyphus jujuba and Atractylodes macrocephala were over than 87% at 1,000 ${\mu}g/mL$, respectively. The highest nitrite scavenging abilities (NSA) of the water and ethanol extracts from Scutellaria baicalensis were 68.9 and 79.2% at 1,000 ${\mu}g/mL$, respectively. Atractylodes macrocephala extracts had shown the highest growth inhibition activity against both of MDA and A549 cells and the water extract had higher activity than ethanol extract. Conclusions : These results suggest that the extracts of medicinal herbs used for this experiment had specific biological activity and they can be used as natural antioxidant to prevent oxidative damage in normal cells.

• Journal of Environmental Health Sciences
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• v.32 no.6
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• pp.556-559
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• 2006

This study was performed to investigate the levels of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in water and rice samples taken from five sites on a stream used for agricultural water in the Jeon-buk area, Korea. The water samples were randomly collected by the recommendations of the World Health Organization, and rice samples were randomly collected from rice paddy. The water and rice samples were analyzed by the recommendations of Food Code of Korea and using inductively coupled plasma spectrometer. Although there was variation between sampling sites, the levels of the metals in rice were on average much higher than those in water. The ratios of metal levels of rice to water were: $8.0{\sim}35.4\;for\;Cd;\;2.2{\sim}7.2\;for\;Cu;\;5.9{\sim}18.3\;for\;Pb;\;and\;10.6{\sim}75.7$ for Zn. These results suggest that there were transfer and bioaccumulation of the metals from the water to the rice taken place.