• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.133-149
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• 1997

4-week repeated dose toxicity of DA-5018, a new capsaicin analogue analgesic agent, was examined in 5D rats at dosage levels of 0,0.4,2, 10 and 50 mg/kg/day. DA-5018 was administered orally to 17 males and 17 females per group at doses of 0, 10 and 50 mg/kg and to 12 males and 12 females per group at doses of 0.4 and 2 mg/kg. After the administration period, 5 males and 5 females at the 0, 10 and 50 mg/kg were placed on withdrawal for 2 weeks. Treatment-related clinical signs were observed at 10 and 50 mg/kg. Clinical signs observed immediately after the administration of DA-5018 were grooming, sedation or depression, lacrimation, atacia, reddening of extremities and ears, ventral or lateral recumvincy, respiratory distress, cyanosis and convulsion. Delayed-type clinical signs including focal scabbing and depilation around nose were also observed 1 or 2 weeks after the start of administration of DA-5018. Only at the 50 mg/kg group, corneal opacities, reduced body weight gain (male) and death (male 6/17, female 3/17) were noted. In blood biochemical analysis, serum levels of glucose and triglyceride decreased at 10 and 50 mg/kg. In hematological examination, there were increases in the number of red blood cell, hemoglobin content and percent of hematocrit at 10 and 50 mg/kg. Pulmonary enlargement and hemorrhagic spot, focal scabbing and depilation around nose and corneal opacities were seen at the necropsy of the animals died during the dosing of DA-5018 50 mg/kg. Focal scabbing and depilation around nose were observed in the animals terminally necropsied at doses of 10 and 50 mg/kg. Histopathological examination revealed pulmonary hemorrhage, focal necrosis in the scabbed area, corneal necrosis, fibrosis and neovasculization in the stroma. At 0.4 and 2 mg/kg, there were no significant toxic changes attributable to the administration of DA-5018. In conclusion, target organs following to 4-week repeated dose of DA-5018 in the rat were determined to be lung, skin and eyes. Definite toxic dose and no-observed-adverse-effect-level (NOAEL) were estimated to be 50 and 2 mg/kg/day, respectively.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.149-152
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• 2012

The larvicidal activities of Piper nigrum fruit methanol extracts and its constituents against larvae of the diamondback moth, Plutella xylostella, were investigated using the leaf dipping method. Administering the P. nigrum methanol extract resulted in 100 and 97% mortality against diamondback moth larvae at 5.0 and 2.5 mg/mL concentrations, respectively. Larvicidal activities of the P. nigrum fruit-derived piperidine alkaloids, piperine, and N-isobutylamide, as well as pellitorine, guineensine, pipercide, and retrofractamide A against P. xylostella varied according to test compound. Based on the 48 h $LC_{50}$ values, the most toxic compound to diamondback moth larvae was guineensine (0.013 mg/mL) followed by retrofractamide A (0.020mg/mL), pipercide (0.033mg/mL), and pellitorine (0.046 mg/mL). The $LC_{50}$ value of piperine was >0.5 mg/mL.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.73-78
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• 2006

In this paper, creep tests of Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys, which were casted by mold with Mg-3%Zn-1%Mn and Mg-3%Zn-1%Mn-0.2%Ca, were done under the temperature range of 473-573K and the stress range of 23.42-78.00Mpa. The activation energies and the stress exponents were measured to investigate the creep plastic deformation of those alloys, and the rupture lifes of Mg-Zn-Mn alloy were also measured to investigate the fracture behavior. From the results, the activation energy of Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys under the temperature range of 473-493K were measured as 149.87, 145.98KJ/mol, respectively, and the stress exponent were measured as 5.13, 6.06 respectively. Also the activation energies Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys under the temperature range of 553-573K were obtained as 134.41, 129.22KJ/mol, respectively, and tress exponent were obtained as 3.48, 4.63, respectively. Finally stress dependence of rupture life and the activation energy of rupture life of Mg-Zn-Mn under the temperature range of 473-493K was measured as 8.05, 170.0(KJ/mol), respectively, which were a little higher than the results of steady state creep.

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.141-149
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• 2017

The influence of the co-additive concentration (0 - 45 wt% with an interval of 5 wt%) of MgO-$TiO_2$ on the phase formation, microstructure and fracture toughness of MgO-$TiO_2$-reinforced dental porcelain nanocomposites derived from a one-step sintering technique were examined using a combination of X-ray diffraction, scanning electron microscopy and Vickers indentation. It was found that MgO-$TiO_2$-reinforced dental porcelain nanocomposites exhibited significantly higher fracture toughness values than those observed in single-additive (MgO or $TiO_2$)-reinforced dental porcelain composites at any given sintering temperature. The amount of MgO-$TiO_2$ as a co-additive was found to be one of the key factors controlling the phase formation, microstructure and fracture toughness of these nanocomposites. It is likely that 30 wt% of MgO-$TiO_2$ as a co-additive is the optimal amount for $MgTi_2O_5$ and $Mg_2SiO_4$ crystalline phase formation to obtain the maximum relative density (96.80%) and fracture toughness ($2.60{\pm}0.07MPa{\cdot}m^{1/2}$) at a sintering temperature of $1000^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1346-1352
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• 2010

This study was conducted to investigate the antioxidant activities of the cultured ginseng with mushroom mycelia (Phellinus linteus (PL), Ganoderma lucidum (GL), and Hericium erinaceum (HE)) during cultivation periods of 10, 20, 30, 40, and 50 days. The lyophilized powder from the cultured ginseng with mycelia was extracted with 80% ethanol, and then evaluated for antioxidant activities. Total phenolic contents ranged from 149.63 to 205.91 mg/g, and the highest value was 80% EtOH extract from the cultured ginseng with GL at 30 days. The highest antioxidant activity ($IC_{50}$) for DPPH was 1.16 mg/mL in the cultured ginseng with HE at 40 days, and total antioxidant activity for ABTS was the highest value of 4.03 mg AA eq/g in PL cultivation at 30 days. $\alpha$-Glucosidase inhibitory activity was the highest value of 92.51% in EtOH extract from the cultured ginseng with PL at 50 days, and tyrosinase inhibitory activity was highest value of 13.21% in GL cultivation at 40 days. These results suggest that mushroom mycelium cultivation period for enhancement of antioxidant activity might be 40 days.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.88-93
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• 2005

The objective of this study was to investigate an influence of the degree of hotness of powdered red pepper on quality attributes of Kimchi. The extent of hotness was analysed by content of capsaicin and dihydrocapsaicin and ASTA color value, and the change of quality attributes of samples were evaluated by pH, acidity, total microbes, lactic acid bacteria cell count and sensory. Content of capsaicin and dihydrocapsaicin in mild red pepper powder was 11.4mg%, 5.4mg% respectively. And content of capsaicin and dihydrocapsaicin in hot red pepper powder was 149.1mg%, 66.0mg% respectively. Kimchi was made with mild and hot red pepper and stored for 24 days at 5±1℃. The pH of Kimchi made with mild red pepper powder during storage of 12 days was slightly lower than that of Kimchi with hot red pepper powder. The pattern of change in pH of samples showed a reducing trend during storage, and the acidity was vice-versa. At day 0, numbers of total bacteria in mild and hot Kimchi were 5.7, 6.7 log cfu/g, respectively. And at day 3, number of total bacteria in mild and hot Kimchi was same. The change in number of lactic acid bacteria was similar to that of total bacteria. In case of sensory evaluation, Kimchi made with hot red pepper powder showed better sensory scores in overall acceptability.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.143-149
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• 2015

This experiment was conducted to evaluate the synergistic effects of vitamin C and E on methylmercury (MeHg) toxicity in juvenile olive flounder Paralichthys olivaceus. In a $3{\times}3$ factorial design, 9 experimental diets containing three different vitamin C (0, 200 or 400 mg/kg diet in the form of l-ascorbyl-2-monophosphate) and vitamin E (0, 100 or 200 mg/kg diet in the form of dl-${\alpha}$-tocopheryl acetate) levels with the Hg toxicity level (20 mg/kg diet in the form of MeHg) were formulated. Triplicate groups of fish averaging $2.3{\pm}0.05g(mean{\pm}SD)$ were fed one of the 9 diets in a flow through system for 8 weeks. Fish fed 400 mg vitamin C/kg diet with 100 or 200 mg vitamin E/kg diet showed significantly (P < 0.05) higher weight gain (WG) than did fish fed the other diets. Fish fed 400 mg vitamin C/kg diet at all vitamin E levels and those which fed vitamin C and E equally at a rate of 200 mg/kg diet showed significantly (P < 0.05) higher feed efficiency (FE), specific growth rate (SGR) and protein efficiency ratio (PER) than did fish fed the other diets. Fish fed 200 and 400 mg vitamin C/kg diet exhibited significantly (P < 0.05) lower Hg concentration in their muscle as well as kidney than did fish fed the other diets. Therefore, these results clearly indicated that the synergistic effects of these two vitamins on MeHg toxicity by supplementing dietary vitamin C (200 and 400 mg/kg diet) with vitamin E (100 and 200 mg/kg diet) in juvenile olive flounder.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.23-30
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• 2016

This study was conducted for comparison of ingredients, phytochemical compounds and antioxidant activity of Wofiporia extensa cultured in Gangwon-do, Gyeongsang-do, and Jeolla-do. Three contents of Wofiporia extensa were analyzed as oxygen (46~48%), carbon (38~39%), hydrogen (6.05~6.1%) and nitrogen (0.17~0.21%). The mineral contents of 50% ethanol Wofiporia extensa extracts were measured as sulfur (S) 145~149 ppm, Magnesium (Mg) 69~72 ppm, phosphorus (P) 122~154 ppm and calcium (Ca) 210.61~509.98 ppm. Wofiporia extensa from Gyeongsang-do (509.98 ppm) contained a significantly higher quantity of Ca than that from Gangwon-do (210.62 ppm) and Jeolla-do (223.88 ppm). In the gas chromatograph-mass spectrometry (GC-MS) analysis, oleic acid was identified in three 50% ethanol Wofiporia extensa extracts. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay for antioxidant activity, the $IC_{50}$ values of Wofiporia extensa cultured in Gangwon-do, Gyeongsang-do and Jeolla-do were calculated as 2.966 mg/mL, 23.03 mg/mL, and 4.16 mg/mL and 3.521 mg/mL, 12.17 mg/mL, and 7.40 mg/mL. In the ferric reducing antioxidant power (FRAP) assay, the $IC_{50}$ values of Wofiporia extensa cultured in Gangwon-do, Gyeongsang-do, Jeolla-do were 6.585 mg/mL, 19.06 mg/mL, and 18.97 mg/mL, respectively. In summary, Wofiporia extensa cultured in Gangwon-do had stronger antioxidant activity and higher concentration of oleic acid than that of Geyongsang-do and Jeolla-do. However, Wofiporia extensa cultured in Geyongsang-do contained a much higher concentration of Ca than that of Gangwon-do and Jeolla-do.

• Parasites, Hosts and Diseases
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• v.26 no.3
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• pp.175-178
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• 1988

In an attempt to analyze the clonorchicidal activity of linoleic acid and ethyl linoleate in vitro, the wormicidal effects on Clonorchis sinensis were chronologically monitored in dose titration experiments. Encysted metacercariae were killed within a period of 31, $0{\pm}4.0$ min, 149.3k4. 1 min and $207.0{\pm}13.5$ min with 100.0 mg, 0.1 mg and 0.001 mg linoleic acid, respectively. The time required for the linoleic acid to kill adult worms was 167, $0{\pm}0.8$ min with 100.0mg, $253.0{\pm}0.8$ min with 0.1mg, and $277.0{\pm}0.8$ min at 0.001mg titration. Clonorchicidal activity of ethyl linoleate was relatively delayed as death was observed within $263.3{\pm}2.9$ min, $286.0{\pm}0.5$ min, and $318.0{\pm}0.8$ min for 100.0 mg/ml, 0.1 mg/ml and 0.001 mg/ml concentrations, respectively. The wormicidal effects observed with these pure anti-clonorchal substances were found to be similar to the biological activity of native products derived from the mucus of the fresh water fish.

• Journal of Ginseng Research
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• v.25 no.4
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• pp.141-149
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• 2001

The effect of ginseng on gastric ulcer and gastric acid secretion was investigated in pylorus-ligated rats. Methods: Sprague-Dawley strain rats were used after 24 hours fast. Pylorus-ligation was performed under light ether anaesthesia, then gastric mucosal damage was evoked in conscious pylorus-ligated rats by the administration of subcutaneous (s.c.) indomethancin (20mg/kg), s.c. histamine (150mg/kg) or by pylorus-ligation (Shay ulcer). Ginseng was given by intragastric (i.g.) or intraperitoneal (i.p.) route simultaneously with the ulcerogens. Rats were killed after 3h (indomethacin) and histamine models) or after 18h (Shay ulcer), when the gastric secretory responses, the number and severity of gastric mucosal lesions and mucosal mucus content deetermined. the effect of i.p. ginseng on basal gastric acid secretion and on gastric acide secretion in indomethacin (20mg/kg, s.c.)-treated rats was also investigated in urethane anesthetized rats. Gastric acid secretion was measured by flushing of the gastric lumen with saline every 15min through an oesophageal cannula. Results: In conscious pylorus-ligated rats, i.g. ginseng(12.5-50mg/$m\ell$; 50-200mg/kg) protected against gastric mucosal lesions evoked by s.c. indomethacin or s.c. histanmine in the d3-h pylorus-lighted rat, withoutmodifying gastric acid secretory responses. Ginseng given i.p. (150 or 200mg/kg) did not reduce the gastric lesions produced by histamine or by ligating the pylorus (Shay ulcer) Ginseng given orally in 50mg/$m\ell$ (200mg/kg) increased gastric mucus secretion in saline- and indomethacin-treated conscious pylorus-ligated rats. In anaesthetized rats ginseng (50 or 200mg/kg) did not modify basal gastric acid secretion or gastric acid secretion in the indomethacin-treated rats. Conclusions: ginseng given orally exerts gastroprotective effects in the rat stomach. Such anti-ulcer effect does not involve changes in gastric acid secretory responses. In addition, ginseng possesses stimulatory effect on gastric mucus secretion, which could be one mechanism by which the compound exerts its antiulcer effect. Our data are in favor for a beneficial effect for topically applied ginseng on the gastric mucosa.