• Toxicological Research
• /
• v.14 no.4
• /
• pp.547-555
• /
• 1998

The subchronic toxicity of a combined preparation of ticlopidine and ginkgo biloba extract (EGb 761) mixed in a ratio of 10: 4 was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance at a dose of 52 mg/kg, 156 mg/kg, or 467 mg/kg intragastrically for 30 consecutive days. Control rats were treated with vehicle only. Each group consisted of 10 rats. No death or abnormal clinical signs were observed throughout the administration period. A transient decrease in body weight gain and food intake was observed in the rats treated with the high dose (467 mg/kg), which was recovered to normal in a week. There were no drug-related differences in urinalysis and hematological results. A significant increase in serum total cholesterol and total protein was observed in both sexes of the rats treated with a dose of 467 mg/kg daily, but all the other values obtained in serum chemistry appeared to be within normal range. A dose dependent increase in liver weight was observed in both male and female rats. Relative kidney weight was also increased in the high dose groups. There was no gross pathological finding at terminal sacrifice. Microscopic histopathological examination did not show any lesion in terms of correlation with administration of the test substance. The results suggest that under the conditions employed in this study no observable effect level (NOEL) of the test substance be 52 mg/kg/day.

• Toxicological Research
• /
• v.16 no.4
• /
• pp.293-301
• /
• 2000

Toxicity of a combined preparation of ticlopidine and ginkgo biloba extract (EGb 761) in a ratio of 10: 4 was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance intragastrically at a dose of 0 mg/kg, 17 mg/kg, 52 mg/kg or 156 mg/kg for 91 consecutive days. No death or abnormal clinical sign was observed throughout the administration period. There was no difference in body weight gain, food intake or water consumption among different dose groups. Test sub-stance-related differences were not observed in urinalysis. In hematological results mean corpuscular hemoglobin (MCH) of low and high dose male group was increased. Prothrombin time of medium and high dose female group was decreased. A significant increase in serum total cholesterol was observed in both sexes of rats treated with a daily dose of 156 mg/kg, but all the other values obtained in serum chemistry appeared to be within normal ranges. A dose dependent increase in the relative liver and kidney weights was observed in both male and female rats. There were no gross pathological findings at terminal sacrifice. Microscopic histopathological examination did not show any lesion associated with administration of the test substance. The results suggest that under the conditions employed in this study no observable effect level (NOEL) of the test substance be greater than 17 mg/kg/day, but less than 52 mg/kg/day.

• Clean Technology
• /
• v.12 no.4
• /
• pp.244-249
• /
• 2006

The photocatalytic degradation of trichloroethlylene (TCE), has been investigated over $TiO_2$ photocatalysts irradiated with solar light. The effect of operational parameters, i.e., initial TCE concentration, $TiO_2$ concentration, pH and additives ($H_2O_2$, persulphate($S_2O{_8}^-$)) on the degradation rate of aqueous solution of TCE has been examined. The results presented in this work demonstrated that degradation of the TCE with $TiO_2/solar$ light was enhanced by augumentation in $TiO_2$ loading, pH, and adding additives but was inhibited by increase in initial TCE concentration. Also individual use of $H_2O_2$ was far more effective than using persulphate in TCE removal efficiency. Furthermore, the relative toxicity with a $solar/TiO_2/H_2O_2$ system was about 15% lower than with a $solar/TiO_2/persulphate$ system and about 35% lower than with a $solar/TiO_2$ system within a reaction time of 150 min, respectively.

• Journal of Ginseng Research
• /
• v.41 no.1
• /
• pp.103-112
• /
• 2017

Background: 20(S)-Protopanaxadiol 20-O-D-glucopyranoside, also called compound K (CK), exerts antidiabetic effects that are mediated by insulin secretion through adenosine triphosphate (ATP)-sensitive potassium ($K_{ATP}$) channels in pancreatic ${\beta}$-cells. However, the antidiabetic effects of CK may be limited because of its low bioavailability. Methods: In this study, we aimed to enhance the antidiabetic activity and lower the toxicity of CK by including it with ${\beta}$-cyclodextrin (CD) (CD-CK), and to determine whether the CD-CK compound enhanced pancreatic islet recovery, compared to CK alone, in an alloxan-induced diabetic zebrafish model. Furthermore, we confirmed the toxicity of CD-CK relative to CK alone by morphological changes, mitochondrial damage, and TdT-UTP nick end labeling (TUNEL) assays, and determined the ratio between the toxic and therapeutic dose for both compounds to verify the relative safety of CK and CD-CK. Results: The CD-CK conjugate ($EC_{50}=2.158{\mu}M$) enhanced the recovery of pancreatic islets, compared to CK alone ($EC_{50}=7.221{\mu}M$), as assessed in alloxan-induced diabetic zebrafish larvae. In addition, CD-CK ($LC_{50} =20.68{\mu}M$) was less toxic than CK alone ($LC_{50}=14.24{\mu}M$). The therapeutic index of CK and CD-CK was 1.98 and 9.58, respectively. Conclusion: The CD-CK inclusion complex enhanced the recovery of damaged pancreatic islets in diabetic zebrafish. The CD-CK inclusion complex has potential as an effective antidiabetic efficacy with lower toxicity.

• The Journal of Internal Korean Medicine
• /
• v.27 no.1
• /
• pp.102-113
• /
• 2006

Objectives & Methods : To obtain the 50% lethal dose(LD50), approximated lethal dose(ALD) and approximated target organs of 'Mahwangyounpae-tang' for further study into such things as repeated dose toxicity, genotoxicity and reproductive toxicity, single dose toxicity was tested in male SD rats according to KFDA Guideline 1999-61[KFDA, 1999] at dosage levels of 2,000, 1,000, 500, 250 and 125 mg/kg/$10m{\ell}$. In this study, mortalities, clinical signs, body weight changes and body weight gains, gross findings and weight of principal organs were detected during and/or after 14 days of single dosing. Results & Conclusions : After 2 or 3 days of dosing, 1 or 2 animals in 2,000 mg/kg-dosing groups died. Excitation and leaping response were observed as test article-treatment related clinical signs. These abnormal signs were restricted to 2,000 and 1,000 mg/kg-dosing groups and survivors recovered to normal within 3 or 4 days after dosing. Significant decrease in body weight were observed in some periods of observation in 2,000 and 1,000 mg/kg-dosing group, from 1 days after dosing compared to those of vehicle control group. Significantly diminished body weight gains were observed in observation periods in 2,000 and 1,000 mg/kg-dosing group compared to those of vehicle control group. Hypertrophy and hemorrhage of heart and decoloration of kidney were observed as test article-treatment related gross findings. These abnormal findings were restricted to 2,000 and 1,000 mg/kg-dosing groups. A significant increase of absolute and relative heart and kidney weight were demonstrated in 2,000 mg/kg-dosing groups. The value for LD50 found in this study was 2,218.57 mg/kg. ALD in this study was 2,000 mg/kg, and the target organs are considered to be the heart and the kidney.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.2
• /
• pp.442-448
• /
• 2006

To obtain the 50% lethal dose (LD50), approximated lethal dose (ALD) and approximated target organs of 'Mahwangyounpae-tang' for further study like repeat dose toxicity, genotoxicity and reproductive toxicity, single dose toxicity was tested in male ICR mouse according to KFDA Guideline 1999-61 [KFDA, 1999] at a dosage level of 2,000, 1,000, 500, 250 and $125\;mg/kg/10m{\ell}$. In this study, mortalities, clinical signs, body weight changes and body weight gains, gross findings and weight of principal organs were detected during and/or after 14 days of single dosing. After 2 or 3 days of dosing, 1 or 2 animals in 2,000 and 1,000 mg/kg-dosing groups were died. Excitation and leaping response were observed as test article-treatment related clinical signs. These abnormal signs were restricted to 2,000 and 1,000 mg/kg-dosing groups and they were recovered to normal within 4 days after dosing in case of survivors. A significant decrease of body weight were observed in some periods of observation in 2,000 and 1,000 mg/kg-dosing group from 1 days after dosing compared to those of vehicle control group. A significant decrease of body weight gains were observed in observation periods in 2,000 and 1,000 mg/kg-dosing group compared to those of vehicle control group. Hypertrophy of heart and decoloration of kidney were observed as test article-treatment related gross findings. These abnormal findings were restricted to 2,000 and 1,000 mg/kg-dosing groups. A significant increase of absolute and relative heart and kidney weight were demonstrated in 2,000 mg/kg-dosing groups. LD50 in this study was detected as 2,242.42 mg/kg. ALD in this study was detected as 1,000 mg/kg and the target organ was considered as the heart and kidney.

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.8
• /
• pp.822-828
• /
• 2005

The photocatalytic degradation of methyl parathion was carried out using a circulating $TiO_2$/solar system. Under the photocatalytic condition, parathion was more effectively degraded than by the photolysis or $TiO_2$ only condition. The parathion degradation followed pseudo first-order kinetics. With photocatalysis, 10 mg/L parathion was completely degraded within 90 min with a TOC decrease exceeding 63% after 150 min. The nitrogen from parathion was recovered mainly as ${NO_2}^-$, ${NO_3}^-$, and ${NH_4}^+$, 80% of sulfur as ${SO_4}^{2-}$, and less than 5% of phosphorus as ${PO_4}^{3-}$ during photocatalysis. The organic intermediates 4-nitrophenol and paraoxon were also identified, and these were further degraded. Two different bioassays using V. fischeri and D. magna were employed to measure the toxicity reduction in the solutions treated by both photocatalysis and photolysis. Relative toxicity was reduced almost completely after 150 min in both organisms under the photocatalysis, whereas in photolysis, 76 and 57% reduction was achieved for V. fischeri and D. magna, respectively. The acute toxicity reduction pattern corresponded with the decrease in parathion and TOC concentrations.

• Clean Technology
• /
• v.17 no.3
• /
• pp.273-279
• /
• 2011

The physicochemical properties of manufactured nanomaterials can vary depending upon the methods of manufacture, although the utilized raw materials are same. Hence, the toxicity can also vary based on the methods of nanomaterials manufacture. In this study, we compared the toxicity effect of two types of CNTs (MWCNT, multi-walled carbon nanotube; SWCNT, single-walled carbon nanotube) that differ in length and wall number. In case of MWCNTs, inflammatory responses were more strongly induced in longer groups, whereas body weights more clearly decreased in shorter groups. SWCNT significantly decreased the relative weights of brain and kidney, and the inflow of immune cells and the hematological changes were observed significantly on day 1 and day 7 after exposure, respectively. Our results showed that the length and wall number of CNTs can serve as critical factors in the exhibited inflammation and toxicity.

• Korean Journal of Food Science and Technology
• /
• v.50 no.6
• /
• pp.629-635
• /
• 2018

In this study, the safety aspect of Maesil-cheongs with reduced amygdalin levels was investigated in terms of toxicokinetics and repeated oral toxicity. Plasma or UVC treatment was utilized to obtain Maesil-cheongs with reduced amygdalin levels. The toxicokinetic study demonstrated that the oral absorption of amygdalin decreased remarkably after a single-dose oral administration of both plasma- and UVC-treated Maesil-cheongs. The fourteen-day repeated oral toxicity study revealed that plasma- or UVC-treated Maesil-cheongs did not cause changes in body weight, food intake, water consumption, and absolute and relative organ weights. No significant effects on hematological and serum biochemical parameters were found. Histopathological examination showed no abnormality or toxicological change. These findings suggest that plasma- and UVC-treated Maesil-cheongs have no toxicity potential, and these processes will be useful to obtain products with safe, reduced amygdalin levels.

• Korean Journal of Environmental Biology
• /
• v.41 no.4
• /
• pp.427-438
• /
• 2023

Biocide dichlofluanid breaks down quickly and accumulates easily in sediment, potentially causing a persistent impact on various marine organisms. We analyzed the potential toxicity of dichlofluanid on major aquaculture species in Korea, Undaria pinnatifida. Female gametophytes of U. pinnatifida were exposed to dichlofluanid at concentrations of 0, 1, 2, 4, 8, 16, and 32 mg L^-1, and their survival and relative growth rate were analyzed. The no observed effect concentration(NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC₅₀) for female gametophyte survival were determined as 1, 2, and 10.82 (95% CI: 8.87-13.23) mg L^-1, respectively. The NOEC, LOEC, and median effective concentration (EC₅₀) for relative growth rate were 1, 2, and 6.58 (95% CI: 6.03-7.17) mg L^-1, respectively. Female gametophytes of U. pinnatifida were expected to experience toxic effects at concentrations above 2 mg L^-1 of dichlofluanid. These research findings are expected to serve as important reference data for evaluating the toxicity effects of U. pinnatifida in its early life stages when exposed to dichlofluanid.