• Proceedings of the PSK Conference
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• 2002.10a
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• pp.419.2-420
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• 2002

Caco-2 is a cell line derived from the human colon adenocarcinoma and often used as a model for studying intestinal drug absorption. It has been well-known that a strong correlation holds between in vitro permeability across Caco-2 cell monolayers and in vivo bioavailability for various drugs. but the correlation curves varied depending on laboratories. The permeabilities of drugs across Caco-2 cell monolayers have been measured under different agitation conditions. (omitted)

• Mycobiology
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• v.38 no.4
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• pp.238-248
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• 2010

This review provides background information on the importance of bioremediation approaches. It describes the roles of fungi, specifically white rot fungi, and their extracellular enzymes, laccases, ligninases, and peroxidises, in the degradation of xenobiotic compounds such as single and mixtures of pesticides. We discuss the importance of abiotic factors such as water potential, temperature, and pH stress when considering an environmental screening approach, and examples are provided of the differential effect of white rot fungi on the degradation of single and mixtures of pesticides using fungi such as Trametes versicolor and Phanerochaete chrysosporium. We also explore the formulation and delivery of fungal bioremedial inoculants to terrestrial ecosystems as well as the use of spent mushroom compost as an approach. Future areas for research and potential exploitation of new techniques are also considered.

• Korean journal of applied entomology
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• v.26 no.4 s.73
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• pp.261-265
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• 1987

Three diffeerent types of symptoms were observed according to the pathogen associated with the rhizomes. The maximum rotting was observed in case when Pythium aphanidermatum was inoculated first followed by Fusarium solani. There was no interaction in case of root knot nematode Meloidogyne incognita and Pythium aphanidermatum. Average per cent germination of the rhizomes were increased significantly in each treatment and maximum in case of Alliette(.25%). The per cent pre & post drenching rotting was minimum in case of Alliette, Burgandy mixture, Dithane-M 45 and Difolatan. These fungicides also increase the yield of rhizome significantly.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.269-276
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• 2009

Black pepper (family Piperaceae), is called king of spices because it is one of the oldest spice and alone accounts for about 35% of the world's total spice trade. The pepper is used in Ayurvedic medicine for the treatment of various ailments particularly neurological, broncho-pulmonary and gastrointestinal disorders. Pepper has also been reported to have various pharmacological actions but recently, it is highlighted as a bioavailability enhancer. This results in higher plasma concentration of drugs, nutrients, ions and other xenobiotics, rendering them more bioavailable for physiological as well as pharmacological actions in the body. Numerous scientific studies reported that piperine; a main bioactive compound of pepper, is responsible for its bioavailability enhancing property. It's a well known fact that pepper enhances bioavailability by inhibition of microsomal enzyme system but other mechanisms are also responsible to acts as a bioavailability enhancer. The brief overview of the mechanism of action of pepper as well as its applications as bioavailability enhancer is given in the present article.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.78-78
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• 2002

Microsomal epoxide hydrolase (mEH), an epoxide detoxifying enzyme and putative cell surface autoantigen, is inducible by xenobiotics and by certain pathophysiological conditions. The present study was designed to determine mEH expression in H4IIE cells during cell death initiated by sulfur amino acid deprivation (SAAD) and to identify the signaling pathway for the enzyme induction.(omitted)

• Toxicological Research
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• v.22 no.1
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• pp.39-45
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• 2006

As the antioxidant and free radical scavenger, glutathione (GSH) participates in the preservation of cellular redox status and defense against reactive oxygen species and xenobiotics. Glutamate-cysteine ligase (GCL; also known as ${\gamma}$-glutamylcysteine synthetase, EC 6.3.2.2) is the rate limiting enzyme in GSH synthesis. In the present study, the accurate method for determination of GCL activity in crude liver extracts was developed by measuring both ${\gamma}$-glutamylcysteine and GSH from cysteine in the presence of glutamate, glycine and an ATP-generating system. We added glycine to promote the conversion of ${\gamma}$-glutamylcysteine to GSH, and to minimize the possibility of ${\gamma}$-glutamylcysteine metabolism to cysteine and oxoproline by ${\gamma}$-glutamylcyclotransferase. We established optimal conditions and substrate concentrations for the enzyme assay, and verified that inhibition of GCL by GSH did not interfere with this assay. Therefore, this assay of hepatic GCL under optimal conditions could provide a more accurate measurement of this enzyme activity in the crude liver extracts.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.44-64
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• 2002

Embryonic prostaglandin H synthases (PHSs) and lipoxygenases bioactivate xenobiotics (phenytoin, thalidomide, benzo[a]pyrene) to free radical intermediates that initiate reactive oxygen species (ROS) formation, which oxidatively damage cellular macromolecules and/or alter signal transduction.(omitted)

• Natural Product Sciences
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• v.12 no.2
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• pp.94-100
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• 2006

The essential oil (EC-oil) obtained from the buds of Eugenia caryophyllata (Myrtaceae) was examined for its free radical-scavenging activity, cytotoxicity, and in vivo toxicity. To find the xenobiotic properties of EC-oil, serum thiobarbituric acid reactive substances (TBARS) level and hepatic drug-metabolizing enzyme activities were measured. It was found that EC-oil displayed xenobiotic properties like bromobenzene. The cytotoxicities of eugenol and of the EC-oil were greatly attenuated by the sulfhydryl-containing N-acetyl-L-cysteine (NAC), suggesting that eugenol was susceptible to nucleophilic sulfhydryl. In addition, eugenol also showed potent free radical-scavenging activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Moreover, methyleugenol considerably exhibited less cytotoxicity and less potent free radical-scavenging activity than eugenol, and the cell viability of the methyleugenol was more increased with NAC treatment than the eugenol. These results indicate that the phenolic OH in eugenol may play a crucial role in both cytotoxicity and free radical-scavenging activity. The fashion on oxidative stress and hepatic drug-metabolizing enzyme activities of eugenol resembled those of bromobenznene.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.95-96
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• 2001

The mutagenic and antimutagenic activities of catechin, hamamelitannin and two proanthocyanidin fractions prepared from the bark of Hamamelis virginia L. - a commonly used medicinal herb - were investigated in a human derived hepatoma (Hep G2) cell line using the single cell gel electrophoresis (SCGE, syn. Comet assay) for the detection of DNA-migration. The cells possess different phase I and phase II enzymes involved in the biotransformation of xenobiotics.(omitted)

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.264-280
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• 1993

The environmental pollutions were a serious problem in Korea recently. So many researcher have studied the effect of environmental pollution on plants and agro-ecosystem, but the basic mechanisms of environmental stresses were various. One of the important mechanisms was oxidative stress caused by active toxic oxygen. The toxic oxygen was generated by several stresses, abnormal temperature, many xenobiotics, air pollutants, water stress, fugal toxin, etc. In the species of toxic oxygen which is primary inducer of oxidative stresses, superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen were representative species. The scavenging systems were divided into two groups. One was nonenzymatic system and the other enzymatic system. Antioxidants such as glutathione, ascorbic acid, and carotenoid, have the primary function in defense mechanisms. Enzymatic system divided into two groups; First, direct interaction with toxic oxygen(eg. superoxide dismutase). Second, participation in redox reaction to maintain the active antioxidant levels(eg. glutathione reductase, ascorbate peroxidase, etc.).