• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1321-1326
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• 2006

Total ginsenosides were purified and their antioxidant, antibacterial and anticancer activities were measured. The crude extracts of ginseng, which were extracted with 75% ethanol by ultrasonification method, were firstly purified on AB-8 macroporous adsorption column to remove water soluble impurities, and decolored on Amberlite IRA 900 Cl anion-exchange column. Then, they were purified on Amberlite XAD16 adsorption column to delete the non-polar impurities. Total ginsenosides contents of the purified extracts were 79.4%, 71.7% and 72.5% in cultured wild ginseng, red ginseng and white ginseng, which were significantly increased than those of crude extracts. All of the three extracts showed concentration-dependant scavenging activities against DPPH radicals, among which white ginseng showed the most powerful activity. Cultured wild ginseng roots showed strongest effect against both B. subtilis PM 125(Gram-positive) and E. coli D31 (Gram-negative) bacteria, while red ginseng and white ginseng only showed the activity against B. subtilis. According to the result of the MTT assay, ail of the three extracts inhibited the growth of U-937 human hohistiocytic lympma cell, which were significantly different (p < 0.05) when compared to the control.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.3
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• pp.249-253
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• 2001

The purpose of this study is the development of the simple and precise sampling and analysis method of methyl isocyanate(MIC) in the work place as their secondary aliphatic amine derivatives by gas chromatography with flame ionization detector. The urea derivatives are quantitatively and simultaneously derived from MIC with secondary aliphatic amines such as dipropylamine(DPA), dibutylamine(DBA), and dipentylamine (DAA) in methylene chloride. The method is based on sampling glass tube in XAD-2 resin which is coated with secondary aliphatic amines. The samples are desorbed by $2m{\ell}$ methylene chloride and analysed using gas chromatography with flame ionization detector(GC/FID). In the results, the detection limit of the overall procedure and reliable quantity are $0.020-0.027{\mu}g$($1.347-1.740{\mu}g/m^3$(0.529-0.684 ppb) based on a 15 L air volume) MIC per sample. The average desorption efficiencies are 97.96 - 101.23 %. The results of versus storage time are high and stable recovery rates.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.286-293
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• 2016

BACKGROUND: 18% of difenoconazole+iminoctadin triacetate microemulsion (3%+15%) formulation were mixed and sprayed as closely as possible to normal practice on the ten of farms located in the Youngju of South Korea. Patches, cotton gloves, socks, masks and XAD-2 resin were used to measure the potential exposure for applicators wearing standardized whole-body outer and inner dosimeter (WBD). This study has been carried out to determine the dermal and inhalation exposure to difenoconazole during preparation of spray suspension and application with a power sprayer on a grape orchard. METHODS AND RESULTS: A personal air monitor equipped with an air pump IOM sampler and cassette and glass fiber filter were used for inhalation exposure. The field studies were carried out in a grape orchard. The temperature and relative humidity were monitored with a thermometer and a hygrometer. Wind speed was measured using a pocket weather meter. All mean field fortification recoveries were between 97.3% and 119.6% in the level of 100 LOQ (limit of quantification) while the LOQ for difenoconazole was $0.025{\mu}g/mL$ using HPLC-UVD. The arms exposure to difenoconazole for the mixer/loader (0.0794 mg) was higher than other body parts (head, hands, upper body, legs). The exposure to difenoconazole in the legs for applicator (3.78 mg) was highest in the parts of body. The dermal exposure for mixer/loader and applicator were 0.02 and 2.28 mg on a grape orchard, respectively. The inhalation exposure during application was estimated as 0.02 mg. The ratio of inhalation exposure to dermal exposure was equivalent to 0.9% of the dermal exposure. CONCLUSION: The inhalation exposure for applicator indicated $18.8{\times}10^{-3}mg$, which was level of 0.9% of the dermal exposure (2.28 mg). Operator exposure (0.004 mg/kg bw/day) to difenoconazole during treatment for grape is calculated as 2.5% of the established AOEL (0.16 mg/kg bw/day).

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.342-347
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• 2004

A bacterial strain YC4963 with antifungal activity against Colletotrichum orbiculare, a causal organism of cucumber anthracnose was isolated from the rhizosphere soil of Siegesbeckia pubescens Makino in Korea. Based on physiological and biochemical characteristics and 16S ribosomal DNA sequence analysis, the bac­terial strain was identified as Pseudomonas aurantiaca. The bacteria also inhibited mycelial growth of several plant fungal pathogens such as Botrytis cinerea, Fusarium oxysporum and Rhizoctonia solani on PDA and 0.1 TSA media. The antifungal activity was found from the culture filtrate of this isolate and the active compound was quantitatively bound to XAD adsorption resin. The antibiotic compound was purified and identified as phenazine-l-carboxylic acid on the basis of combined spectral and chemical analyses data. This is the first report on the production of phenazine-l-carboxylic acid by Pseudomonas aurantiaca.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.302-311
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• 2018

BACKGROUND: Dithianon (75%) formulation were mixed and sprayed as closely as possible by normal practice on the ten farms located in the Mungeong of South Korea. Patches, cotton gloves, socks, masks, and XAD-2 resin were used for measurement of the potential exposure of dithianon on the applicators wearing standardized whole-body outer and inner dosimeter (WBD). This study has been carried out to determine the dermal and inhalation exposure to dithianon during preparation of spray suspension and application with a power sprayer on a apple orchard. METHODS AND RESULTS: A personal air monitor equipped with an air pump, IOM sampler and cassette, and glass fiber filter was used for inhalation exposure. The field studies were carried out in a apple orchard. The temperature and relative humidity were monitored with a thermometer and a hygrometer. Wind speed was measured using a pocket weather meter. All mean field fortification recoveries were between 85.1% and 99.1% in the level of 100 LOQ (limit of quantification), while the LOQ for dithianon was $0.05{\mu}g/mL$ using HPLC-DAD. The exposure to dithianon on arms of the mixer/loader (0.0794 mg) was higher than other body parts (head, hands, upper body, or legs). The exposure to dithianon on the applicator's legs (3.78 mg) was highest in the body parts. The dermal exposures for mixer/loader and applicator were 10 and 8.10 mg, respectively, from a grape orchard. The inhalation exposure during application was estimated as 0.151 mg, and the ratio of inhalation exposure was 11.2% of the dermal exposure (inner clothes). CONCLUSION: The dermal and inhalation exposure on the applicator appeared to be 4.203 mg - 25.064 mg and $0.529{\mu}g-116.241{\mu}g$, respectively. The total exposures on the agricultural applicators were at the level of 2.596 mg - 25.069 mg to dithianon during treatment for apple orchard. The TER showed 3.421 (>1) when AOEL of dithianon was used as a reference dose for the purpose of risk assessment of the mixing/loading and application.