• Journal of Industrial Technology
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• v.28 no.B
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• pp.65-69
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• 2008

The tailings piled in abandoned mines are well-known potential sources of soil contamination. Hydrated limes were applied as cementing materials to solidify heavy metal contaminated tailings for the purpose of reducing their toxicity and migration rates. The optimum mixing ratio of tailings, hydrated lime, and water was determined through a preliminary test. The mixtures of mine tailings and hydrated lime solidified through pozzolanic reaction were tested for their durability against repeated freezing and thawing processes. After repeated freezing and thawing, the uniaxial compressive strengths of all the solidified mixture specimens decreased in comparison with those before test but still higher than $3.5kgf/cm^2$, the standard recommended for land reclamation solids by EPA(Environmental Protection Agency), which suggested that hydrated lime be a potential material to treat the abandoned mine tailings for the environmental purpose.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.63-67
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• 2007

Laccase catalyzes the oxidation and polymerization of aromatic compounds in the presence of molecular oxygen. The oxidative transformation of chlorophene with laccase was conducted in a closed, temperature controlled system. The optimal pH for transformation of chlorophene was proven to be about 5-6. As the temperature rose up to $55^{\circ}C$, the transformation of chlorophene increased. The chlorophene transformation was not enhanced in the presence of soluble polymers. The toxicity of the reaction mixture was increased two times than that of initial reaction mixture after the enzymatic treatment. ABTS has enhanced chlorophene transformation at 0.1 mM and showed negative linear relationship with residual chlorophene by the reaction.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.106-113
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• 2020

BACKGROUND: Bumblebees have been shown to be very effective pollinators for most greenhouse tomatoes. Neonicotinoid insecticides are one of the most widely used pesticides in tomato crops in Korea. METHODS AND RESULTS: This study was carried out to investigate the toxicity of four neonicotinoid insecticides (clothianidin, dinotefuran, imidacloprid and thiamethoxam) to bumblebees based on the OECD guidelines (No.246, 247). The 48 hr LD₅₀ (㎍ a.i. /bumblebee) values in the acute contact toxicity tests were determined as follows: clothianidin, 0.467; dinotefuran, 3.741; imidacloprid, 3.967; and thiamethoxam, 0.747. The 48 hr LD₅₀ values in the acute oral toxicity tests were determined as follows: clothianidin, 0.005; dinotefuran, 0.056; imidacloprid, 0.325; and thiamethoxam, 0.018. The acute contact and oral toxicity of the test insecticides to bumblebees from most to least toxic was clothianidin > thiamethoxam > dinotefuran > imidacloprid. CONCLUSION: This study provided the basic toxicological data of neonicotinoid insecticides for bumblebees. In the near future, acute toxicity and mixture toxicity of other pesticides to bumblebees could be determined using this method.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.77-81
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• 2001

Kamijadowhan (KMD), an oriental herbal medicine used for anti-angiogenic effect, was extracted with 80% ethanol from mixture of source materials and lyophilized. KMD was orally administered to plugpositive pregnant rats from gestational days 12 to 20, dividing into three groups including vehicle-treated control, 0.5 g/kg or 3 g/kg KMD-treated groups. Dam weight during gestation and post-gestation, weight of pre- and post-weaning offsprings in male and female, and reproductive and developmental endpoints including incisor eruption, eye opening and testes descent were measured. No significant alterations in development of physical landmarks in offspring, maternal weight gain during gestation and post-gestation, and offspring weight were observed in KMD-treated group. The measurement of organ weight at post-gestational days 21 was not changed in dams. In 0.5 g/kg KMD-treated rats, kidney weights in male and female offsprings were significantly increased, and the body weight in male offspring was also increased. Liver and brain weights were not changed. Taken together, these data suggest that KMD may not significantly cross the placenta and produce no reproductive and developmental toxicity at maternally non-toxic dosages.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.136-142
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• 2012

Various factors affecting on the bioassay were investigated. Experiments with a low mixture ratio (cell to toxicant solution) of 0.5 : 9.5 (v/v) produced observable bioluminescence intensity for assay. Both sodium lactate and potassium nitrate stimulate bioluminescence activity; 2.6~4.0 times of control. Distilled water and MSM, which gave non significant effects on the bioluminescence activity, were determined as proper diluent or extract solutions. A wide range of toxic responses of metals and organics were observed. In general, organics were much less sensitive than metals. Samples collected from eleven sites showed the bioluminescence activity ranging from 29 to 111% of the control. Significant correlation between toxicity and total metal contents was not observed, but the toxicity of two groups, sorted based on the contaminated arsenic concentration in soils, was 44% and 20%, showing considerable differences.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.219-219
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• 2002

The SPP003 is a mixture of water extract from Schizandrae Fructus, Poligoni multiflori Radix, Ginseng Radix Akba and Hoelen. The aim of this study was to investigate the anti-hyperglycemic effect of SPP003 in normal and streptozotocin (STZ)-induced diabetic rats, and to monitor the toxicity of SPP003. Oral glucose tolerance test (OGTT) was performed after oral administration of SPP003 100, 300, 600 and 900 mg/kg in normal rats. Blood glucese concentration was measured at -30 min (vehicle, SPP003 or tolbutamide 60 mg/kg, 0 min (glucose treatment), 60, 120 and 180 min. Rats were administerd STZ 65mg/kg (0.1M citrate buffer, pH 4.5) intraperitoneally to induce diabetes and administered vehicle, Spp003 (100, 300 and 600 mg/kg) or tolbutamide (60 mg/kg) orally once a day for 4 weeks. Blood glucose level was measured a 0, 4, 7, 14, 21 and 29 day after initial drug administration. A single oral toxicity of SPP003 was studied in Sprague-Dawley rats of both sexes. In this study, rats were administered with doses of 1, 2 and 5 g/kg of SPP003. In glucose tolerance test, SPP003 900 mg/kg markedly decreased glucose concentration at 1 hr after glucose treatment. Blood glucose levels were much higher in STZ-diabetic rats. These increases were significantly attenuated by SPP003 600 mg/kg. SPP003 did not show any signigicant toxicity. These findings suggest that SPP003 has hypoglycemic properties in STZ-diabetic rats.

• Korean Journal of Animal Reproduction
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• v.16 no.3
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• pp.269-276
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• 1992

Studies were carried out to find the freezing media which gives no ice crystals in single(glycerol, ethylene glycol, dimethyl sulfoxide(DMSO)) and mixture solutions(glycerol＋propylene glycol, glycerol＋ethylene glycol) of permeable cryoprotectants in vitrification solution and to study effects of VS on the survival of vitrified mouse morulae. The results are summarized as follows: 1. In toxicity test of permeable cryoprotectants, 30% glycerol of single solution showed the highest FDA-score(4.1) in mouse morulae frozen compared among other single solutions. The FDA-score(4.1) of 30% glycerol was higher than 30% ethylene glycol(3.6) and DMSO(1.4( (P<0.05). 2. 20, 30 or 40% single solution of permeable cryoprotectants containing m-PBS with 10% sucrose and 20% BSA was not crystallized during cooling, but crystallized during warming. However, the 30% mixture solution of the two permeable cryoprotectants was not crystallized both during cooling and warming.3. When mouse morulae were frozen in 30% mixture solutions of two permeable cryoprotectants(glycerol and propylene glycol, glycerol and ethylene glycol), highest FDA-score(4.5) was obtained in a mixture solution of 20% glycerol and 10% ethylene glycol(20G10E) than other 30% mixture solutions(10G20E, 15G15E, 20G10P, 15G15P, 10G20P) and there was significant difference between 20G10E and 10G20E(P<0.05).

• Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.11.1-11.8
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• 2019

Background: In the present study, the skin-whitening effects of a marine-sourced mixture that includes a fucoidanrich extract of Undaria pinnatifida (UPEF), a phlorotannin-rich extract of Ecklonia cava (ECE), and glycosaminoglycans (GAGs) from sea squirt skin were investigated. Methods: The whitening effects of the mixture and its components were evaluated by measuring the inhibition of mushroom tyrosinase and melanin synthesis in alpha-melanocyte-stimulating hormone (${\alpha}$-MSH)-stimulated B16F10 melanoma cells. Results: Each component alone markedly inhibited mushroom tyrosinase in a dose-dependent manner, and in ${\alpha}$-MSH-stimulated B16F10 cells, they inhibited melanin synthesis and were cytotoxic. However, the whitening effects of UPEF, ECE, and GAGs in combination were greater than those of each component alone. A mixture in the ratio of 4:5:1 (UEG-451) showed the strongest activity without cytotoxicity. Further study suggested that UEG-451 inhibits ${\alpha}$-MSH-stimulated melanogenesis in B16F10 cells by downregulating tyrosinase and tyrosinase-related proteins, such as TRP-1 and TRP-2, via the inhibition of MITF expression. Conclusions: These results suggest that mixing the different components at optimum ratios might be an effective way to improve their bioactivities and reduce toxicity and that UEG-451 possesses strong whitening effects that could be used in the cosmetic industry.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.2
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• pp.189-198
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• 2012

Our former study indicated efficacy of apoptotic cell death on animal study by using Egg white combined Chalcanthite (EC). Clinically, bamboo salt is using because of safety. Hence we investigated a toxicity study for determining safety by adding bamboo salt in former materiel. We had two studies: toxicity of EC and of Bamboo salt with egg white combined Chalcanthite (BC). Both were studied in 1-week single and 5-week repeated oral dose toxicity tests on male Imprinting Control Region mice. In EC, doses used in 1 week single oral dose toxicity tests were 0, 0.05, 0.5, 5 and 50 mg/kg/day and 0, 0.01, 0.05, 0.25 and 0.5 mg/kg/day. In BC, doses used by 0, 0.08, 8.3, 83.3 and 166.6 mg/kg/day in single oral dose toxicity and 0, 4.2, 8.3, 41.7 and 83.3 mg/kg/day in repeated oral dose toxicity tests. Their blood and urine were assayed and organ morphology were examined. Mann-Whitney U test and ANOVA tests were used by analysing methods. First, significant increased left renal weight in all groups of EC and BC. Second, increased ALT score was found in EC-S2 and increased relative liver weight was found in EC-S3. In addition, increased relative weight and urine bilirubin and urobilinogen were found in EC-R2 and EC-R3. There was no significant toxic change in BC. The Mixture of EC had a possibility of hepatotoxicity in the short and long term. Processed BC appears to be safe and non-toxic in these studies and a no-observed adverse effect level (NOAEL) was established at 83.3 mg/kg/day in mice. Relatively, The BC were safer than The EC.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.547-555
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• 2009

This study was performed to determine the minimum dose of Poloxamer/Sodium alginate (PX/SA) mixture on preventing intraperitoneal adhesions to evaluate organ toxicity. Twenty five healthy adult mongrel dogs (weighing 4.68${\pm}$1.67 kg) were divided into five experimental groups composed of five dogs respectively; negative control group (NC, non-treated), positive control group (PC, 2% carboxymethyl chitosan solution treated), and experiment 1 group (E1, 0.25 ml PX/SA mixture of abraded area), experiment 2 group (E2, 0.5 ml PX/SA mixture of abraded area), experiment 3 group (E3, 1.0 ml PX/SA mixture of abraded area). Venous blood specimens were collected from all experimental animals for hematologic and biochemical analysis: WBC, fibrinogen, AST, ALT, ALP, BUN and creatinine. The anti-adhesion effect was evaluated using a serosa abrasion model. The denuded ileum was coated with PX/SA mixture, carboxymethyl chitosan solution or neither. The tensile strength of the adhesion site was evaluated with a tensiometer. For histopathological examination, tissue samples of the liver and kidney were collected from all dogs. According to the results, the frequency and tensile strength values for adhesion separation in PX/SA group were significantly lower than those in negative control group (p < 0.05). In E2 group, the tensile strength was significantly decreased in consideration of PX/SA dose. The values of AST, ALT, ALP, BUN and creatinine of the control and the experimental groups showed no statistical differences. No obvious microscopic differences were noted among tissue sections obtained from all groups. The results suggest that PX/SA mixture may be effective on reducing peritoneal adhesion formation in dog and that 0.5 ml PX/SA mixture of abraded area is most effective dose. Moreover, PX/SA mixture was considered not to have toxicity for the liver and the kidney.