• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.901-908
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• 2014

Blueberries and strawberries are highly perishable and easily contaminated with microorganisms. To maintain the quality of these commodities during refrigerated storage, the effects of two packaging materials as well as passive modified atmosphere packaging on the quality of blueberries and strawberries were investigated. The harvested blueberries and strawberries were first treated with combined non-thermal treatment of aqueous chlorine dioxide and fumaric acid, followed by packaging with polyolefin film (6,000 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$) and polyamide/polyamide/polyethylene film (PA/PA/PE, 60 mL $O_2/m^2{\cdot}24hr{\cdot}atm$ at $24^{\circ}C$), respectively. After combined sanitizer treatment, the populations of total aerobic bacteria in blueberries and strawberries were reduced by 2.50 and 1.97 log CFU/g while those of yeast and molds were reduced by 1.95 and 2.18 log CFU/g, respectively, compared with the control. In particular, microbial growth in these samples packed with PA/PA/PE film was reduced during refrigerated storage. In addition, the blueberries and strawberries packed with PA/PA/PE film underwent lower weight loss than those packed with polyolefin film during storage. These results suggest that appropriate packaging with proper gas permeability is necessary to maintain the quality of blueberries and strawberries during refrigerated storage.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.27-31
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• 2007

Trifloxystrobin standard was analyzed by high performance liquid chromatography (HPLC). The recovery of the trifloxystrobin and it's metabolite CGA321113 were $84.6{\sim}95.3%$ and $86.4{\sim}87.3%$ and their detection limits for both of them were 0.04 mg $kg^{-1}$. In case of foliar application in the chinese cabbage (Brassica campestris L. ssp pekinnensis (Lour.) Rupr.), the amount of the residue of trifloxystrobin was above the maximum residue level (temporary MRL, 0.5 mg $kg^{-1}$) when it was treated either two times three to five days before harvest or three times three to seven days before harvest. Whereas in case of drenching the mount of the residue was below the temporary MRL, the residues in the cabbage in both the cases where the recommended amount (150 mL of the solution diluted 1500 times) and double of the amount were treated were 0.16 and 0.31 mg $kg^{-1}$, respectively. In conclusion, it should be safe to apply the trifloxystrobin (22% WP) in the soil of cabbage field abiding by the tentative recommendation level, but for the foliar application it appeared inappropriate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.4
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• pp.316-320
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• 2015

In order to improve the transformation efficiency of zoysiagrass by increasing the frequency of callus formation from mature seeds and plant regeneration, the effect of pre-treatment with sea sand was examined. Mature zoysiagrass seeds were given 10 min of swelling time before sea sand treatment using a sea sand and seed ratio of 1 : 1 and a vortex shaking speed of 6 (1,000 rpm) for 10 min. The seeds showed increased callus formation that was more than 2 times the rate in the control. In addition, plant regeneration efficiency was also increased when embryogenic callus induced from sea sand-treated mature seeds was cultured in regeneration medium. These results will be very helpful for improving the genetic transformation frequency of zoysiagrass, a recalcitrant monocot grass.

• Analytical Science and Technology
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• v.25 no.5
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• pp.307-312
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• 2012

To perform inhalation toxicity test by using experiment animals, we set up an analytical method to monitor didecyldimethylammonium chloride (DDAC) in aerosol nebulized into inhalation chambers by ion chromatography. DDAC was adsorbed by XAD-2 resin and analyzed with conductivity detector. Recovery of DDAC desorbed by acetonitrile from XAD adsorbent was 87.8%. The method detection limit (MDL) and the limit of quantitation (LOQ) were 2.97 ${\mu}g/m^3$ and 8.92 ${\mu}g/m^3$, respectively. Repeatability was calculated as RSD 7.8% in the range of 0~20 ${\mu}g/mL$. Time needed to analyze a sample was less than 5 minutes. Therefore, the analysis of DDAC by ion chromatography was practically useful in monitoring DDAC in inhalation chambers with rapidity and sensitivity manner to perform inhalation toxicity test using experimental animals.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.149-155
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• 2002

Two pesticides commonly used for lettuce cultivation including chlorpyrifos and procymidone were subjected to a field residue trial to ensure safety of terminal residues in the harvest. After pesticides were applied at standard and double rates in a foliar spray, leaf persistence of their residues was investigated far 10 days prior to harvest. Even though far exceeded the tolerances, initial leaf residues were rapidly dissipated with time and remained only 0.4$\sim$7.2% of the residues in the harvest. As well fitted by the first-order kinetics, biological half-lives of the pesticide residues in lettuce leaves ranged 1.2$\sim$2.6 days. Slow dissipation of the residues in the harvest was observed during storage at room temperature and 4$^{\circ}C$ for 7 days. Portions of dislodgeable residues which resided in detergent washings decreased as time elapsed. Patterns in dissipation and distribution of dislodgeable residues were not largely affected by the application rate of pesticides. It is concluded that timing of pesticide application, that is, pre-harvest interval would be the first factor to determine the terminal residue level in edible portions of lettuce.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.63-75
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• 2007

A survey on sanitary management at 98 food service institutions located in Jeollabuk-Do were conducted. Food service institutions included 13 hospitals, 38 schools, 40 enterprises, and 7 others. The sterilization in boiling water was used for disinfection of tableware, spoon and chopsticks, and dish towel. Cooking kit, refrigerator, chopping board, and knife were sterilized with disinfectant. Frequency of sanitary training program on employees was 56.1% for 1 time/month, 12.2% for 2-3 times/month, and 11.3% for 1 time/week. Preparing ratio of defrosting, warehouse and rest room, and washing and sterilization diary were 73.8, 60.5, and 54.5%, respectively. However, checking ratio of environments (9.5%), personal sanitation (10.8%), and sanitary training program diary(8.4%) were low. Major obstacle factors on the introduction of Hazard analysis critical control point (HACCP) system into food service institutions were lack of equipment and facilities (54.1%) and lack of understanding and data on HACCP system (17.3%). Therefore, in order to reduce the outbreak of food-borne diseases increasing frequency, we estimated that the introduction of sanitary management system and the conversion of dietician' perception on sanitary managements in food service institutions were needed.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.204-211
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• 2012

Although Arcobacter butzleri is a foodborne emerging pathogen causing gastroenteritis in human and animals, there are a few researches on the physical and chemical control methods. The aim of this study was to investigate the effect of ultraviolet radiation or ethanol treatment on A. butzleri. To demonstrate the UV effect, 8 ${\log}_{10}CFU$/mL of A. butzleri were spiked on stainless steel and the pork was then exposed to 250 nm of ultraviolet light for 108-648 mWs/$cm^2$. To ascertain the effect of ethanol, A. butzleri and A. butzleri spiked pork were soaked or sprayed 10, 35 and 70% of ethanol for 10 to 30 min. A. butzleri significantly decreased all of the UV doses in stainless steel, whereas, the reduction was just $0.92{\pm}0.62-1.29{\pm}0.34\;{\log}_{10}CFU$/mL in pork spiked with A. butzleri. In the ethanol groups, A. butzleri decreased significantly in 35% or 70% of ethanol in contrast, the bacterial counts were dropped slightly in A. butzleri spiked pork groups. Therefore, it is necessary to develop various kinds of control methods or hurdle technology for A. butzleri.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.441-452
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• 2011

This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.481-495
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• 2015

The study researched germination of the plants and growth of Fungus according to concentration of aqueous extracts in order to provide basic data for developing natural agricultural resources by using Persicaria longiseta. The seed germination of Amaranthus spinosus was inhibited at 25% P. longiseta extract, while Agrostis stolonifera ssp. palustris was not affected at all concentrations tested. Especially, the seed germination rate and fresh weight of Trifolium incarnatum at 20% P. blumei extract were higher than those of control plot. The early growth of most receptor plant seedlings was promoted at 25% and 50% of P. blumei extracts, but the radicle growth of all receptor plants was significantly inhibited at > 25% of P. longiseta extract. The response of receptor plants to P. longiseta extract was different according to the plant species and the plant parts. The growth of plant pathogenic fungus in PDA medium showed an increasing inhibition tendency with increasing concentrations of P. longiseta extract. Especially, P. longiseta extract showed the greatest antimicrobial activity against Phytophthora infestans, Phythium graminicola, and Pythium venterpoolii. The content of total phenolic compound in P. longiseta was higher in leaves (1082.3 mg/L) but lower in roots (228.6 mg/L) and stems (207.8 mg/L), which is an allelopathic chemical. As these results are summarized, P. longiseta have competitive advantage because they release phenolic compounds with allelopathic effect and affect on germination, growth and fungi growth on underground flora compared to native plants and they have eligibility for natural herbicide and germicide.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.959-963
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• 2001

To investigate the antimicrobial effects of Scutellariae Radix extract against L.monocytogenes from foods, L. monocytogenes strains isolated from livestock, processed food from meat and milk, and frozen foods, were examined for their sensitivity to Scutellariae Radix extract. 30 L. monocytogenes strains were isolated from total 178 samples(16.9%); 13(14.0%) strains from beef 6(20.7%) strains from pork, 9(39.2%) strains from chicken and 2 (16.7%) strains from frozen foods but was not found from processed products, The serotypes of isolated L.monocytogenes were serotype O-1 strains (23, 76.7%) and serotype O-4 strains(7, 23.3%) on antisera agglutination test. The growth curves of isolates were shown lag phase, logarithmic phase, stationary phase and death phase as typical sigmoid curve on the preservative-free hams. After 6 hours. Scutellariae Radix extract contain group differ from control group on preservative-free ham samples, and the isolates were inhibited in more than 1000 ppm Scutellariae Radix extract on the inhibitory growth curve of L.monocytogenes. The mor-phological changes were observed by transmission electron microscope and the microbial cells membrane was destroyed by Scutellariae Radix extract.