• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.499-505
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• 2016

To improve the shelf-life of mushrooms, Lentinula edodes GNA01 mushrooms were treated with gel packs containing slow-released chlorine dioxide ($ClO_2$) gas at 5~10 ppm for 5 days at $20^{\circ}C$ and the weight loss rate as well as the changes in pH, color and texture properties of the treated samples were investigated. The weight of the control and $ClO_2$ gas treated samples were decreased slightly, and there were no differences during the storage period. However, the weight of the control changed faster than those of the $ClO_2$ gas treated samples during storage period. The pH in the control and in the $ClO_2$ gas treated samples were decreased during storage period, but the samples treated with 5 and 7 ppm $ClO_2$ gas were the least changed. On the other hand, the samples treated with 10 ppm $ClO_2$ gas showed no difference from the other treatments during 4 days, but the pH was lower than that of the control on the fifth day. The lightness of inside and outside in mushroom were decreased whereas redness and yellowness were increased during storage period. However, color changes in the $ClO_2$ gas treated samples were lower than those of the control. Especially, the samples treated with 5 and 7 ppm $ClO_2$ gas were the least changed. The texture of the mushroom were decreased consistently during storage period. The texture of the control changed faster than those of the $ClO_2$ gas treatments during 5 days. Especially, the samples treated 5 ppm $ClO_2$ gas were the least changed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.39-45
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• 1996

The study was performed to investigate the effects of administration of aluminum compound in Kidney metabolism and plasma hormone of rats. Seventy frve male Sprague-Dawley strains rats were divided into five groups consisting of the control, 250ppm AlCl$_3$group, 500ppm AlCl$_3$ group, 250ppm $Al_2$(SO$_4$)$_3$group, 500ppm $Al_2$(SO$_4$)$_3$group and kept on the diet for 2 weeks. The body weight gain was increased by the administration of AlCl$_3$ but decreased by the administration of $Al_2$(SO$_4$)$_3$as compared to the control. The urinary excretion of sodium and creatinine were increased and free water clearance and urine volume were decreased significantly after AlCl$_3$adminstration group as compared to the control. The water balance, free water clearance, excretion of sodium and creatinine were increased and the excretion of chlorine was decreased after $Al_2$(SO$_4$)$_3$ administration as compared to the control. Plasma renin activity was increased and plasma aldosterone content was compared to the control. Plasma renin activity was increased and plasma aldosterone content was significantly decreased after adminstration of aluminum compounds as compared to the control.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.241-245
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• 2002

최근 시설재배에서는 염류 집적 및 토양전염성 병해충 등으로 인한 연작장해를 회피하기 위하여 수경재배로 전환하는 농가가 급속히 증가하고 있다. 우리나라의 수경재배면적은 '98년 23 ha에서 2000년 1,000 ha로 급속히 증가하고 있는데, 이중 약 12％는 담액수경이나 박막수경의 순수 수경재배 방식이 차지하고 있으나 대부분이 고형배지를 이용한 비순환방식이다. 배양액의 비순환방식은 토양이나 지하수의 오염이 염려되지만, 순환방식의 경우에는 배양액 성분의 조정이나 배양액의 소독 등재처리가 필요하여 농가에서는 기피하고 있는 실정이다. (중략)

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.45-45
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• 2017

The Indian meal moth, Plodia interpunctella, is one of the most important pests of stored food in the food processing industry worldwide. To control the Indian meal moth, methyl bromide, phosphine, high carbon dioxide, sulfuryl fluoride and plant essential oil fumigation have been considered. However, these treatments have disadvantages. For example, depleting the ozone layer, showing resistance in insect, low control efficacy or need high cost for treatment. Chlorine dioxide ($ClO_2$) is strong disinfectant and insecticide. The gas caused a malfunction in enzymes. The oxidative stress induced by $ClO_2$ gas treatment damaged to a physiological system and all life stages of P. interpunctella. The gaseous $ClO_2$ is a convincing alternative to methyl bromide for controlling P. interpunctella. The gaseous $ClO_2$ was generated by a chlorine dioxide generator (PurgoFarm Co., Ltd., Hwasung, Korea). It generated highly pure $ClO_2$ gas and the gas blown out through a vent into a test chamber. Gas entry to the chamber was automatically controlled and monitored by a PortaSene II gas leak detector (Analytical Technology, Collegeville, PA, USA). The properly prepared eggs, larvae, pupae, and adults of P. interpunctella were used in this experiment. Data were analyzed using SAS 9.4. Percentage data were statistically analyzed after arcsine-root transformation. Analysis of variance was performed using general linear model, and means were separated by the least significant difference test at P < 0.05. Fumigation is an effective management technique for controlling all stages of P. interpunctella. We found that $ClO_2$ gas treatment directly effects on egg, larvae, pupae and adults of P. interpunctella. The gas treatment with proper concentration for over a day achieved 100 % mortality in all stages of P. interpunctella and short time treatment or low concentration gas treatment results showed that the egg hatchability, pupation rate, and adult emergency rate were lowered compare with untreated control. Also, abnormal pupae or adult rate were increased. Gaseous $ClO_2$ treatment induced insecticidal reactive oxygen species (ROS), and it resulted in fatal oxidative stress in P. interpunctella. Taken together, these results showed that exposure proper concentration and time of the gas control all stages of P. interpunctella by inducing fatal oxidative stress. Further studies will be required to apply the gas treatment under real-world condition and to understanding physiological reaction in P. interpunctella caused by oxidative stress.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.317-321
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• 2013

This study was conducted to investigate the antimicrobial effect of freely available chlorine (FAC) on the vase life of cut rose 'Brut' (Rosa hybrida L.). Postharvest treatments to extend the vase life of cut roses were divided into holding solution treatment and pulsing solution treatment. In holding solution treatment, the cut roses were treated with the preservative solutions containing FAC (0, 10, 20, and $40mg{\cdot}L^{-1}$) and sucrose (0 and 2%, w/v). In pulsing solution treatment, cut roses were dipped into the FAC solutions of 100, 200, and $400mg{\cdot}L^{-1}$ for 10 seconds. The longest vase life of cut roses was observed in the holding solution with FAC $20mg{\cdot}L^{-1}$ as 12 days, followed by pulsing with $400mg{\cdot}L^{-1}$ as 11 days, which were four or five days longer than the control. In addition, relative fresh weight and water uptake were the highest in the holding solutions with FAC 20 and $40mg{\cdot}L^{-1}$. The antimicrobial effect of FAC in vase solution was lasted for eight days after treatment, which was offset by sucrose addition. FAC contents in the FAC holding solution mixed with sucrose were exhausted by 88% two days after treatment, whereas only 15% of FAC was reduced in the holding solution without sucrose. This study indicated that FAC can be applied to extension of the postharvest life of cut roses by antimicrobial activity.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.2059-2065
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• 2000

The purpose of this study is to improve coagulation efficiency by pre-treatment of high pH water using sulfuric acid. The common reason of pH increasing at down stream of Nakdong river is water blooming. The pH go above 9.0 during water blooming periods. The higher pH water demands more coagulant and pre-chlorine dosage than lower pH water for better coagulation condition. The DOC, THMFP, UV-254 after coagulation with the same coagulant dosage by pre-treatment from pH 9.2 down to 8.1 with sulfuric acid are 1.84mg/L, $51{\mu}g/L$ and $0.032cm^{-1}$, by pretreatment of chlorine are 2.09mg/L, $78{\mu}g/L$ and $0.030cm^{-1}$, by pre-treatment of sulfuric acid and chlorine are 2.14mg/L, $72{\mu}g/L$ and $0.031cm^{-1}$ respectively. Pretreatment with sulfuric acid can improve water quality and reduce coagulant demand.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.83-87
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• 2014

The effects of combined treatment of aqueous chlorine dioxide ($ClO_2$) and fumaric acid on the microbial growth in fresh-cut paprika were investigated. After the combined treatment, the populations of total aerobic bacteria and inoculated Listeria monocytogenes in the paprika sample were reduced by 0.82 and 1.21 log CFU/g, respectively, compared to those of the control. In addition, after 10 d of storage at $10^{\circ}C$, the populations were decreased by 1.21 and 2.10 log CFU/g, respectively. The predictive model for the populations of total aerobic bacteria and L. monocytogenes in the paprika was applied during storage. The prediction equation using Gompertz model was appropriate, based on the statistical analysis such as accuracy factor and bias factor. These results suggest that the combined treatment of aqueous $ClO_2$ and fumaric acid can be an effective technology for microbial decontamination and it can improve microbial safety by decreasing maximum growth rate and increasing lag time of bacteria in the fresh-cut paprika.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1233-1238
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• 2016

Combined treatment of chlorine dioxide ($ClO_2$) gas, mild heat, and fumaric acid was performed to reduce microbial growth and maintain quality of Citrus unshiu during storage at $4^{\circ}C$. Citrus unshiu fruits were treated with $ClO_2$ gas (15 or 30 ppmv), mild heat (40, 50, or $60^{\circ}C$), and fumaric acid (0.1, 0.3, or 0.5%). Combined treatment of 15 or 30 ppmv $ClO_2$ gas, $50^{\circ}C$ mild heat, and 0.5% fumaric acid reduced populations of inoculated Listeria monocytogenes by 3.5~3.7 log CFU/g. In addition, combined treatment decreased populations of yeast and molds in Citrus unshiu by 2.54 log CFU/g after 30-day storage at $4^{\circ}C$. Combined treatment also reduced the decay rate by 48% after 30 days of storage compared with the control. Total solid content, titratable acidity, and color values were not significantly affected by the combined treatment. Therefore, combined treatment of $ClO_2$ gas, mild heat, and fumaric acid can be a useful hurdle technology to improve microbial safety and quality of Citrus unshiu during storage.

• Journal of Aquaculture
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• v.16 no.3
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• pp.151-158
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• 2003

This study was conducted to estimate the effects of residual chlorine dioxide ($CIO_2$) in chlorinated seawater on survival and physiological responses (hematocrit: Ht, hemoglobin: Hb, serum electrolyte and glucose levels, and osmolality) of olive flounder, Paralichthys olivaceus. All the flounders were exposed for 10 min to different concentrations of residual $CIO_2$ just after chlorination for 1 min in each experimental aquarium (EA). ClO$_2$-free seawater was continuously supplied to each EA after 10 min exposure to $CIO_2$. By means of probit analysis, the median lethal times (LT$_{50}$, min) of flounder exposed to 0.43 and 0.51 ppm $CIO_2$, were at 103 and 32 min, respectively. In the range from 0.34 to 0.51 ppm $CIO_2$, the values of Ht, Hb, electrolytes and osmolality of fish exposed to $CIO_2$ were significantly elevated as elapsed time and residual concentrations of $CIO_2$ increased after chlorination. The levels of Ht, Hb, electrolytes and osmolality in flounder exposed to 0.27 ppm $CIO_2$ were not significantly different compared to control fish, which were maintained in $CIO_2$-free seawater; however, the levels of serum glucose were significantly increased with elapse times.

• Journal of Life Science
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• v.16 no.4
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• pp.579-583
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• 2006

The influence of disinfectant on bacterial concentration and carbon usage patterns by Biolog GN plates were investigated for biofilm on carbon steel pipe. Heterotrophic bacterial concentrations were not different among non-, monochloramine- (1.0, 1.5 mg/l) and free chlorine- (0.5, 1.0 mg/l) treated samples (P = 0.56, ANOVA). However treatment of 1.5 mg/l free chlorine and 2.0 mg/l monochloraime showed significantly lower densities than control (P < 0.01, ANOVA). By the stepwise increasement of disinfectant concentration, the carbon usage activities of biofilm microflora were decreased after increase without the decrease of bacterial concentration, following reduction of cell density. Carbon usage patterns were qualitatively and quantitatively different with similar bacterial concentrations. Principal component analysis suggested that type and concentration of disinfectant were main factors on the usage of carbons. Our result suggest that the differences of bacterial communities were different among the samples and the need of monochloramine for the reduction of biofilm in drinking water.