• Proceedings of the Korean Society of Toxicology Conference
• /
• 2002.05a
• /
• pp.127-127
• /
• 2002

Methallothioneins(MTs) are low-molecular-mass cysteine-rich metal-binding proteins with high affinity for heavy metal ions, found in a large variety of organisms. Although the biological functions of MTS have not been fully elucidated, they are thought to play an important role in detoxification of toxic elements such as cadmium and mercury.(omitted)

• Bulletin of Food Technology
• /
• v.17 no.4
• /
• pp.117-128
• /
• 2004

Sulforaphane은 브로컬리나 십자화과 채소중의 glucoraphanin의 가수분해 산물인 isothiocyanate로서 이는 detoxification 효소의 phase II를 일으키는 것으로 나타났고 설치류에서 화학적으로 발생된 유선 종양을 억제하고 최근에는 대장암 세포에서 cell cycle arrest와 apoptosis를 일으킨다고 알려져 왔다. 여기서는 SUL이 Human MammaryMCF-7 adenocarcinoma 세포의 증폭을 억제하는 역할을 제시하였다. MCF-7 cell에 15umol/L SUL을 처리하였을 때 G2/M cell cycle이 arrest를 보였고 cyclin B1 protein이 24시간 이내에 증가하였다. 15umol/L의 SUL은 in vivo 상에서 histon Hl의 인산화를 유도하고, 초기 mitosis에서 cell을block하며 mitotic microtuble의 중합화를 방해하였다. In vitro 상에서 정제된 bovine braintubulin에 대한 SUL을 고농도로 투여했을 때, tubulin의 중합율과 총 tubulin 중합도의 억제를 보였다. 덧붙여서, isothiocyanate를 함유하는 SULanalog로 처리된 정제 tubulin도 비슷하게 저해를 받았다. 본 연구는 SUL이 mitotic cell cyclearrest를 포함한 mammary cancer 억제력을 가진 것과, 이러한 기작으로 정상적인 tubulin 중합화및 microtubule dynamic에 한층 효과적인 영향을 준다는 것을 제시하였다.

• International Journal of Oral Biology
• /
• v.40 no.4
• /
• pp.217-221
• /
• 2015

Cariogenic Streptococcus mutans encounters a variety of host defense factors produced in oral cavity. Nitric oxide (NO) and NO-mediated reactive nitrogen species are potential antimicrobials of innate immunity that can threaten the fitness of S. mutans in their ecological niches. Streptococcal strategies to detoxify cytotoxic NO, which allow S. mutans to persist in caries or other environments of the oral cavity, remain unknown. In this study, we directly measured NO consumption rates of S. mutans isolated in Korea. Surprisingly, all S. mutans strains were unable to consume exogenous NO efficiently, while an intracellular parasite Salmonella enterica serovar Typhimurium expressing the NO-metabolizing enzyme flavohemoglobin consumed most of the NO. This result suggested that S. mutans has alternative detoxification systems for tolerating NO-induced nitrosative stresses.

• Toxicological Research
• /
• v.17 no.4
• /
• pp.303-308
• /
• 2001

The potential for a given anticholinesterase pesticide to exhibit age-related toxicity is essential information for an accurate and proper risk assessment of that compound. This investigation was designed to study the age-related toxicity of active metabolites of four organophosphates using in vitro detoxification measurement. The blood samples were collected from 1 month and 18 months old rats. The $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrifos-oxon, diazoxon, malaoxon and paraoxon were 10.35, 112.84, 151.28 and 18.43 nM, respectively. When the plasma of young rats, and $CaCI_2$were added, the $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrfos-oxon, diazoxon, malaoxon and paraoxon were 31.89, 164.25, 139.94 and 16.36 nM, respectively. The $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrifos-oxon, diazoxon, malaoxon and paraoxon were changed to 136.840, 1244.45, 654.54 and 52.66 nM by A-esterases In adult rats. These results suggest that four organophosphates have a potential toxicity to exhibit age-related sensitivity.

• Biomolecules & Therapeutics
• /
• v.12 no.3
• /
• pp.185-188
• /
• 2004

The purpose of this study is to evaluate the effect of cigarette smoke condensate (CSC) on toxification/detoxification metabolic pathway in primary cultured rat hepatocytes. We measured the activities of cytochrome P450 monooxygenases (CYP450s) and UDP-glucuronyltransferase, sulfotransferase and glutathione-S-transferase in CSC-treated rat hepatocytes. CSC significantly increased the activities of hepatic CYP4501A1 and CYP4501A2 to 7.5 fold and 1.6 fold respectively, compared with control level. However, CSC did not affect the activities of conjugation enzymes. We a1so examined if treatment of CSC could change thc cytotoxicity of acetaminophen (AA) through modulation of metabolizing enzymes. In rat hepatocytes, pretreatment with CSC potentiated the cytotoxicity of AA. This result indicates that potentiation of AA toxicity by CSC pretreatment may be related to induction of CYP4501A1 and CYP4501A2.

• Toxicological Research
• /
• v.1 no.1
• /
• pp.17-30
• /
• 1985

Mycotoxins are a group of toxicants giving a risk potential to human health in connection with the daily food intake. Food commodities once contaminated with mycotoxins can not be detoxified by any economic means and prevention was suggested as the only measure. In order to minimize the economic loss and health hazard posed by mycotoxins and toxicoses, systematic and toxicological studies on the subject should be undertaken. Most reports in Korea were concentrated on the mycological studies of relatively easy techniques and the confirmation or quantitation of mycotoxins was rarely done. Research topics to be undertaken in future may be exemplifid below: (1) Establishing assay methods for individual or multi-residue of mycotoxins (2) Monitoring of mycotoxins for suspicious food or feed samples in Korea (3) Epidemiological survey of mycotoxicoses (4) Etiological survey of disease outbreaks associated with mycotoxins (5) Accumulation of testing method and data on the toxicity of mycotoxins (6) Legal regulation to control mycotoxins and development of their detoxification / elimination methods

• Mycobiology
• /
• v.44 no.2
• /
• pp.67-78
• /
• 2016

Rice contaminated with fungal species during storage is not only of poor quality and low economic value, but may also have harmful effects on human and animal health. The predominant fungal species isolated from rice grains during storage belong to the genera Aspergillus and Penicillium. Some of these fungal species produce mycotoxins; they are responsible for adverse health effects in humans and animals, particularly Aspergillus flavus, which produces the extremely carcinogenic aflatoxins. Not surprisingly, there have been numerous attempts to devise safety procedure for the control of such harmful fungi and production of mycotoxins, including aflatoxins. This review provides information about fungal and mycotoxin contamination of stored rice grains, and microbe-based (biological) strategies to control grain fungi and mycotoxins. The latter will include information regarding attempts undertaken for mycotoxin (especially aflatoxin) bio-detoxification and microbial interference with the aflatoxin-biosynthetic pathway in the toxin-producing fungi.

• Journal of Ginseng Research
• /
• v.16 no.2
• /
• pp.99-104
• /
• 1992

Korean red ginseng and water extract residue of red ginseng roots were treated with dry heat and incorporated in PDA medium to examine the effect of the materials on induced tolerance against mercury chloride and mycelial growth of Fusarium oxysporum. Ginseng residue was not effective in the inducement of tolerance to mercury chloride regardless of dry heat treatment. However, the heat treatment of ginseng and ginseng residues stimulated the mycelial growth of the fungus. The materials responsible for the detoxification appeared to be water-soluble. The stimulation of the fungal mycelial growth on the media by the heat treatment was highest in the water extract of ginseng. Due to the heat treatment, the mycelial growth was also slightly increased in n-hexane and methanol extracts of ginseng, compared with the ginseng fractions without dry heat treatment.

• The Korean Journal of Zoology
• /
• v.30 no.3
• /
• pp.231-238
• /
• 1987

생쥐의 체장, 신장 및 혈청내 LDH 활성에 있어서 간장과 신장에서는 염화메틸수은 투여군과 염화 메틸수진-홍삼추출물 투여군의 총 LDH 활성치가 대조군에 비하여 감소되었으나 염화 메틸수은-홍삼추출물 투여군의 활성치는 염화메틸수기 투여군 보다 약간 감소되었다. 혈청에서는 염화 메틸수은 투여군의 LDH 활성치가 대조군에 비하여 2배로 크게 증가되었으며 염화 메틸수은홍삼추출물 투여군의 활성치는 대조군과 유사하였다. LDH isosyme의 전기영동상에 있어서 간장의 대조군과 염화 메틸수은-홍삼적출물 투여군에서는 5가지 LDH isoBym삐 모두 나타났으나 염화 메틸수진투여군에서는 LDH1 제외한 4가지 LDH isosyme 나타났다. 신장과 혈청에서는 3군 모두에서 5가지 LDH isozyme 나타났다.

• YAKHAK HOEJI
• /
• v.59 no.5
• /
• pp.222-229
• /
• 2015

Lithospermi radix, the dried roots of Litospermum erythrorhizon Sieboid et Zuccarini (Boraginaceae), has long been used to treat detoxification and inflammation. In this study, we isolated two main quinoid compounds, ${\beta}$-hydroxyisovalerylshikonin (1) and acetylshikonin (2) from L. erythrorhizon. As acetylshikonin is considered as a marker compound of L. erythrorhizon, a rapid analysis method for the simultaneous determination of quinoid compounds including 2 was also developed by HPLC (High Performance Liquid Chromatography) and validation of this analytical method. By the developed method, two quinoid marker compounds (${\beta}$-hydroxyisovalerylshikonin and acetylshikonin) were successfully quantified in 31 commercial samples which were collected from different regions. The contents were 0.20% (${\beta}$-hydroxyisovalerylshikonin) and 0.22% (acetylshikonin), respectively.