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Chinju, South Korea

Kim H.J.,Kyungpook National University | Lim J.-S.,Kyungpook National University | Kim W.-K.,Korea Institute of Toxicology | Kim J.-S.,Kyungpook National University
Proceedings of the Nutrition Society | Year: 2012

Glyceollins, one family of phytoalexins, are de novo synthesised from daidzein in the soyabean upon exposure to some types of fungus. The efficiency of glyceollin production appears to be influenced by soyabean variety, fungal species, and the degree of physical damage to the soyabean. The compounds have been shown to have strong antioxidant and anti-inflammatory activities, and to inhibit the proliferation and migration of human aortic smooth muscle cells, suggesting their potential to prevent atherosclerosis. It has also been reported that glyceollins have inhibited the growth of prostate and breast cancer cells in xenograft animal models, which is probably due to their anti-oestrogenic activity. In essence, glyceollins deserve further animal and clinical studies to confirm their health benefits. © 2011 The Authors.

Jun S.Y.,INtRON Biotechnology Inc. | Jung G.M.,INtRON Biotechnology Inc. | Yoon S.J.,INtRON Biotechnology Inc. | Choi Y.-J.,Seoul National University | And 3 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2014

Phage endolysins have received increasing attention as potent antibacterial agents. However, although safety evaluation is a pre-requisite for the drug development process, a good laboratory practice (GLP)-compliant safety evaluation has not been reported for phage endolysins. A safety evaluation of intravenously administered SAL200 (containing phage endolysin SAL-1) was conducted according to GLP standards. No animals died in any of the safety evaluation studies. In general toxicity studies, intravenously administered SAL200 showed no sign of toxicity in rodent single- and repeated-dose toxicity studies. In the dog repeated-dose toxicity test, there were no abnormal findings, with the exception of transient abnormal clinical signs that were observed in some dogs when daily injection of SAL200 was continued for more than 1 week. In safety pharmacology studies, there were also no signs of toxicity in the central nervous and respiratory system function tests. In the cardiovascular function test, there were no abnormal findings in all tested dogs after the first and second administrations, but transient abnormalities were observed after the third and fourth administrations (2 or 3 weeks after the initial administration). All abnormal findings observed in these safety evaluation studies were slight to mild, were apparent only transiently after injection, and resolved quickly. The safety evaluation results for SAL200 support the implementation of an exploratory phase I clinical trial and underscore the potential of SAL200 as a new drug. We have designed an appropriate phase I clinical trial based on the results of this study. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Um M.Y.,Korea Food Research Institute | Hwang K.H.,Korea Institute of Toxicology | Ahn J.,Korea Food Research Institute | Ha T.Y.,Korea Food Research Institute
Basic and Clinical Pharmacology and Toxicology | Year: 2013

Curcumin is a well-known component of traditional turmeric (Curcuma longa), which has been reported to prevent obesity and diabetes. However, the effect of curcumin on hepatic lipid metabolism remains unclear. The aim of this study was to examine the effects of curcumin on hepatic steatosis in high-fat/cholesterol diet (HFD)-induced obese mice. Male C57BL/6J mice were fed a normal diet (ND), HFD or HFD with 0.15% curcumin (HFD+C) for 11 weeks. We found that curcumin significantly lowered the body-weight and adipose tissue weight of mice in the HFD+C group compared with the findings for the HFD group (p < 0.05). The levels of total cholesterol, fasting glucose and insulin in serum were decreased, and HFD-induced impairment of insulin sensitivity was improved by curcumin supplementation (p < 0.05). Curcumin protected against the development of hepatic steatosis by reducing hepatic fat accumulation. Moreover, curcumin activated AMP-activated protein kinase (AMPK) and elevated the gene expression of peroxisome proliferator-activated receptor alpha. By contrast, curcumin suppressed the HFD-mediated increases in sterol regulatory element-binding protein-1, acetyl-CoA carboxylase 1, fatty acid synthase and cluster of differentiation 36 expression. Taken together, these findings indicate that curcumin attenuates HFD-induced hepatic steatosis by regulating hepatic lipid metabolism via AMPK activation, suggesting its use as a therapeutic for hepatic steatosis. © 2013 Nordic Pharmacological Society.

Seo J.-S.,Korea Institute of Toxicology
Journal of the Korean Society for Applied Biological Chemistry | Year: 2012

Mycobacterium aromativorans JS19b1T, isolated from a polycyclic aromatic hydrocarbon (PAH)-contaminated site in Hilo, Hawaii, USA, was studied for its degradation of dibenzothiophene (DBT) as a sole carbon source. Strain JS19b1T degraded 100% of DBT (40 mg/L) within 11 days incubation through branched metabolic pathways, including dioxygenation on C-1,2 and C-3,4 positions and monooxygenation on sulfur atom. The metabolites were isolated and identified by gas chromatography-mass spectrometry. Dibenzothiophene-5,5′-dioxide was transformed from sulfur oxidation of DBT. Cis-dibenzothiophene dihydrodiols were detected as initial dioxygenation products. Two ring cleavage products of dibenzothiophene diols were detected as trans-4-(3-hydroxybenzo[b]thiophen-2-yl)-2-oxobut-3-enoic acid and trans-4-(2-hydroxy-benzo[b]thiophen-3-yl)-2-oxobut-3-enoic acid, which could be produced by meta-cleavage of dibenzothiophene-1,2-diol and dibenzothiophene-3,4-diol, respectively. The detection of benzothienopyranone strongly supported that M. aromativorans JS19b1T can degrade DBT through 1,2- and/or 3,4-dioxygenations followed by meta-cleavage. The ring cleavage products were further transformed into 2,2′-dithiosalicylic acid via 2-mercaptobenzoic acid. These results suggested that strain JS19b1T has diverse lateral dioxygenase and metabolic enzyme systems. The diverse DBT metabolic pathways in JS19b1T gave a new insight to the bacterial degradation of aromatic compounds. © 2012 The Korean Society for Applied Biological Chemistry.

Hwang Y.S.,Korea Institute of Toxicology | Qu X.,Rice University | Li Q.,Rice University
Carbon | Year: 2013

The photochemical transformation of carboxylated multiwall carbon nanotubes (COOH-MWCNTs) in water and the subsequent impact on their aggregation and deposition behaviors were examined. The photochemical transformation of COOH-MWCNTs was investigated under UVA (300-400 nm) irradiation, the main component of UV light in solar irradiation. Time-resolved dynamic light scattering measurement and quartz crystal microbalance with dissipation monitoring were used to study the initial aggregation and deposition kinetics. Characterization of the physicochemical properties of the COOH-MWCNTs before and after irradiation revealed a loss in surface oxygen after UV irradiation, most likely a result of decarboxylation of the nanotube surface. These changes in surface chemistry greatly reduced the colloidal stability of COOH-MWCNTs in NaCl solutions. No noticeable changes in particle surface zeta potential and stability were observed in CaCl2 solutions after irradiation. Consistent with the decreased colloidal stability in NaCl solutions, the irradiated COOH-MWCNTs had a notably higher deposition than the initial COOH-MWCNTs in NaCl solutions when aggregation did not occur. Our results suggest that the photochemical transformation plays an important role in the transport of carbon nanotubes in natural aquatic systems. © 2012 Elsevier Ltd. All rights reserved.

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