• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.174-177
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• 1993

Ultara violet ray air cleaner to use as the sterilization and deodorization device in refrigerator was designed and made of UV lamp and carbon block as the main components. The intensity of the lamp was $2.38\;mW/cm^2$ and reflector was installed to increase the radation. After running the device for 12 hours, 80% of the population of airborn bacteria was sterilized both at 48 and 480 liter refrigerator chambers. Ozone production caused by UV-ray reached 0.082 ppm at holding section within a few second when the device was operated at $25^{\circ}C$ and it showed 0.06 pm at $3^{\circ}C$. Deodorization effect was 2.5 times greater than that of a device made of electrical are principle at $25^{\circ}C$. New device 2 times more effectivly decreased trimethylamine and methyl mercaptan content applied as odor indicator substance in chamber at $3^{\circ}C$ than electrical arc type.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.61-67
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• 2001

Five hundred sixteen isolates of Botrytis elliptica were isolated from infected leaves of Lilium longiflorum from Kangwon alpine areas in Korea during tile seasons from 1998 to 2000 and resistance of these isolates against some fungicides were examined. The isolation frequency of phenotypes resistant to benomyl, procymidone, and diethofencarb were 90.1, 32.4, and 40.9%, respectively. The isolates were divided into six phenotypic groups; RSS, RRS, SSR, SRR, RSR and RRR, representing sensitive (S) or resistant (R) to benzimidazole, dicarboximide, and N-phenylcarbamate fungicides in order. The percentage of six phenotypes were 40.7, 8.5, 7.2, 2.7, 19.8, and 21.1%, respectively. The RSS phenotype was the most frequently isolated, and tile SRR consisted of the extremely minor populations. In comparison studies on tile overwintering ability of each phenotype in relation to the others, the most frequently isolated RSS and SSR had the higher fitness ability than the less frequently isolated RSR, SRR, and RRR. Recently, population increase of tile RSR and RRR phenotypes may have resulted from the increased applications of the mixture of carbendazim and diethofencarb to control benzimidazole-resistant B. elliptica since 1998. The results of this study indicate that careful application of the fungicides is necessary to achieve effective control of leaf blight on lily in Korea.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1029-1034
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• 1999

To enhance the cleaning and sterilization effect of cooled electrolyzed acid water on lettuce, several kinds of polysorbates were used at various concentrations in immersion washing process. In case of the treatment containing polysorbate 20, coliform count of lettuce was reduced to about 1/40 level of that in non-treated lettuce. The treatment containing polysorbate 60 did not show a significant sterilization effect. Otherwise, the total and coliform counts of lettuce during immersion in electrolyzed acid water containing 1 ppm of polysorbate 80 was reduced to about 1/300 and 1/1,700 level of those in non-treated one. And, the changes of ORP(oxidation-reduction potential), pH and color value of lettuce in electrolyzed acid water containing 1 ppm of polysorbate 80 were not quite different during 60 min. immersion, but HCIO content decreased from 10.28 ppm to 8.51 ppm after 20 min. immersion. Also, total and coliform count of lettuce immersed in electrolyzed acid water containing 1 ppm of polysorbate 80 was lower to about 1/1,800 after 20 min. and 1/5,550 after 30 min, compared with non-treated lettuce.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.232-237
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• 1996

Toxicity of 5 acaricides, 4 insecticides. and 6 fungicides to the twospotted spider mite, Tetranychus urticae Koch, and its predator Amblyseius womersleyi Schicha was assessed in a laboratory using a leaf disk bioassay. Dicofol was equally very toxic to aduly females of T. urticae and A. womersleyi, and caused 46% and 40% mortality of eggs of those two species, respectively. Adult females of A. womersleyi dipped in Abamectin solution showed low mortality(16.6%), while all T. urticae females died within 24 hours after dipping. Three ovicidal acaricides (Tetradifon, Clofentezine, and Hexythiazox) showed no mortality of predator eggs, but more than 90% mortality of T. urticae eggs. Four insecticides (Teflubenzuron, Triflumuron, Diflubenzuron, and Imidacloprid) and three fungicides (Propineb, Fenarimol, and Polyoxin-B captan) were non toxic to the A. womersleyi adult females. The other fungicides (Chlorothalonil, Nuarimol.Mancozeb, and Folpet) were a little toxic to adult females of the predator, showing$\leq$23.3% mortality, It may be suggested from these results that 4 insecticides, 4 acaricides, and 6 fungicides described could be incorporated into the integrated pest management system with A. womersleyi in apple orchard.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.1-9
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• 2010

In order to survey residual characteristics of pesticides in the agricultural products selling at markets and to assess their safety, a total of 120 agricultural products were collected from the wholesale and traditional markets in Cheongju and analyzed the pesticide residues in them by multiresidue analysis method using GLC, HPLC and GC-MSD. Three pesticides, procymidone, penconazole, and tetraconazole, were detected from 4 samples such as onion, leek, tomato, and green pepper. Fungicide penconazole was detected from the onion collected from wholesale market. Fungicide procymidone was detected from leek and tomato and fungicide tetraconazole was detected from green pepper. Pesticide residues were detected from 3.3% of the total samples. The estimated daily intakes (EDIs) of the pesticides detected were less than 0.1% of their acceptable daily intakes (ADIs), representing that residue levels of the pesticides detected were evaluated as safe.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.128-133
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• 1997

This study was conducted to evaluate the adsorption, desorption, leaching and degradation pattern of fungicide fluazinam in the soil environment under the laboratory conditions. The mode of isothermal adsorption of fluazinam in soil was coincident with the Freundlich equation. The adsorption amount of fluazinam was much higher on soils containing organic matter than on soils oxidized with hydrogen peroxide. The presence of organic matter, humic acid or fulvic acid, increased the adsorption amount of fluazinam on soils. The Freundlich constant K was much higher in soil added with humic acid than in soil added with fulvic acid. The desorption ratio of fluazinam adsorbed to soil was increased by removal of organic matter. In leaching experiment using soil column, the fluazinam applied on the soil surface was not moved down to the bottom of soil and was not detected in leachate water. The degradation of fluazinam was faster in Soil I with rich organic matter than Soil II with poor organic matter, in non-sterilized soil than sterilized soil, and in flooded soil than unflooded soil.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.197-203
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• 2019

This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

• The Korean Journal of Mycology
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• v.27 no.1 s.88
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• pp.10-14
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• 1999

A single phase composter was constructed by modifying the conventional mixer of sawdust for the cultivation of oyster mushroom Pleurotus ostreatus. The machine was designed on the basis of 3-phase-1 system which was controlled in prewetting, pasteurization and fermentation processes. In composting 200 kg of straw and cotton waste in the machine, it took 20 minutes in prewetting step and also to hours at $65^{\circ}C$ in pasteurization process. Postfermentation by aerothermophiles was completed by treating the compost at $45^{\circ}C-50^{\circ}C$ for 48 hours which was shorten 24 hours from the conventional method. In the postfermentation at high temperature, forced aeration and/or vigorous mixing process(es) played a great role in the improvement of spawn quality. The growth of mycelium of oyster mushroom was excellent in the culture combinated with 3 parts of surface inoculation and 7 parts of mechanical mixing.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.371-380
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• 2010

This study was performed to develop a precise single residue analytical method of fungicide cyprodinil in representative crops for using as general residue analytical methods which could be applied to most of crops. Apple, mandarin, Korean cabbage and green pepper were selected as representative crops, and they were macerated, extracted with acetonitrile, concentrated and partitioned with n-hexane. Then the extracts were concentrated and cleaned-up through silica gel column with ethyl acetate:n-hexane (15:85, v/v) before concentration and analysis with HPLC. LOQ (limit of quantitation) of cyprodinil was 5 ng (S/N>10) and MQL (method qnantitation limit) was 0.05 mg/kg. Recoveries were measured at three fortification levels (MQL, 10MQL and 100MQL) on crop samples and ranged from 82.0 to 108.2% and coefficients of variation were less than 10% regardless of sample type.

• Applied Biological Chemistry
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• v.26 no.4
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• pp.239-247
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• 1983

The effects of some soil conditions on the degradation rate and decomposing pattern of parathion were investigated and the obtained results are summarized as follows: Parathion degraded more rapidly in flooded soils than in non-flooded, in wet soils than in dry soils under non-flooded soils. The degradation rates in paddy and upland soils increased at high temperature than low temperature, higher pesticide concentration than low concentration and higher soil pH level. Parathion in paddy and upland soils was more persistent under soil sterilization than under non-sterilization and degraded rapidly in glucose application. Parathion was more persistent in upland soils than paddy soils under several factors described above. The metabolites identified from the paddy and upland soils by TLC include para-oxon (Rf 0.5), aminoparathion(Rf 0.27), p-nitrophenol(Rf 0.2), p-aminophenol(Rf 0.15). Soil enzyme, acid phosphatase activities decreased more at flooded soils than non-flooded, higher pesticide concentration than low concentration and higher soil pH level and the activity in glucose application was increased. Soil enzymes, urease and dehydrogenase activity decreased more at higher pesticide concentration than low concentration. Comparing with soil enzyme activity in paddy and upland soil, the former was higher than the latter.