• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1207-1213
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• 2020

Aflatoxin B1 (AFB1) is a mycotoxin produced by Aspergillus flavus (A. flavus). AFB1 is reported to have high thermal stability and is not decomposed by heat treatment during food processing. Therefore, in this study, knowing that AFB1 is metabolized by cytochrome P450 (CYP), our aim was to develop a method to detoxify A. flavus-contaminated maize, under normal temperature and pressure, using Escherichia coli expressing human CYP3A4. First, the metabolic activity of AFB1 by recombinant human CYP3A4 was evaluated. As a result, we confirmed that recombinant human CYP3A4 metabolizes 98% of AFB1. Next, we found that aflatoxin Q1, a metabolite of AFB1 was no longer mutagenic. Furthermore, we revealed that about 50% of the AFB1 metabolic activity can be maintained for 3 months when E. coli expressing human CYP3A4 is freeze-dried in the presence of trehalose. Finally, we found that 80% of AFB1 in A. flavus-contaminated maize was metabolized by E. coli expressing human CYP3A4 in the presence of surfactant triton X-405 at a final concentration of 10% (v/v). From these results, we conclude that AFB1 in A. flavus-contaminated maize can be detoxified under normal temperature and pressure by using E. coli expressing human CYP3A4.

• Toxicological Research
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• v.11 no.2
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• pp.241-246
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• 1995

This study was carried out to develop the antitoxic compound about cytotoxicity of cadmium on cultured rat neuroglial cells. These cells divided into 3 groups; control group (medium only) or $MTT_{50}$ group (neuroglial cell, $61{\mu}M$ cadmium) and experimental group ($61{\mu}M$ caffeic acid). Neutral red (NR) and tetrazolium MTT of the colorimetric assay were performed to evaluate the cytotoxicity of cell organelles. The light microscopic study was carried out to morphological changes of cultured rat neuroglical cells. The results indicated that caffeic acid showed detoxification effect on cytotoxicity of cadmium in $61{\mu}M$ concentration. According to the spectroscopic study of 1:1 complex of cadmium and caffeic acid, it showed that this formation of complex eliminated cadmium from cultured rat neurogllal cells.

• Journal of the Korean Wood Science and Technology
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• v.35 no.4
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• pp.52-60
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• 2007

Plant can detoxify the effect of the volatile organic compounds (VOC) such as formaldehyde and toluene, however, mechanisms of VOC detoxification are largely unknown in plant system. This study was performed to investigate phenotypic changes of Arabidopsis seedlings upon treatment of either formalin or toluene. Formalin treatment up to twenty four hours didn't cause any significant phenotypic damages on the leaf surface of 27 DAG Arabidopsis seedlings. However, the protein profile of formalin-treated seedlings was significantly different from that of mock control. Using automated electrophoresis system, the molecular weight of each formaldehyde-responsive protein (FRP) was predicted and its formaldehyde-dependent expression was confirmed at transcription level by quantitative real-time RT-PCR analysis. Four FRPs isolated in this study are the novel proteins with unknown functions but highly homologous to the stress-related proteins.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.893-899
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• 1996

The studies on the detoxification of paralytic shellfish poison (PSP)-infested blue mussels, Mytilus edulis and oyster, Crassostrea gigas were performed for using of available processing resource. Toxic blue mussel and oysters from Nampo in Masan Bay, Hachong in Koje Bay and Woepori in Koje were used for experimental samples. The toxicity of low toxic blue mussel $(A,\;84{\mu}g/100g;\;B,\;166{\mu}g/100g;\;C,\;295{\mu}g/l00g;\;D,\;557{\mu}g/100g)$ and oyster $(740{\mu}g/100g)$ were reduced below the regulation limit of PSP $(80{\mu}g/100g)$ or undetected level by mouse bioassay after boiling at $98^{\circ}C$ for 10 min and retorting at $115^{\circ}C$ for 70 min, while the toxicity of high toxic blue mussel $(E,\;8,760{\mu}g/100g)$ remained beyond the regulation limit after boiling and retorting at same condition. These results suggested that the regulation limit of PSP could be level up from $(80{\mu}g/100g)$ to about $160{\mu}g/100g$.

• Korean Journal of Pharmacognosy
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• v.20 no.1
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• pp.25-31
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• 1989

In order to establish the standard method for the preparation of processed Aconiti Tuber, Aconiti Tubers were processed under various conditions and the amount and the composition of alkaloids were determined by HPLC. The ratio of sum of benzoylhypaconine and benzoylmesaconine over the sum of acinitine, mesaconitine, benzoylmesaconine and benzoylhypaconine was used as a detoxification index ((BM+BH)${\times}$100/MA+AC+BM+BH). The adequate value of index was obtained from Japanese 'ka-gong bu-ja' which has been used in Japan. The processing procedure was largely devided into two categories. First is heat treating at $120^{\circ}$ and 1. 2 lbs for 60 min. Second is treatment with various kinds of alkaline solutions followed by heat treatment at $120^{\circ}$ and 1. 2 lbs for 60 min. Among the source of processed Aconiti Tubers, dried bu-ja and yom bu-ja, dried bu-ja was more adequate than yom bu-ja because yom bu-ja has the lower value of index than dried bu-ja and lost active components through the desalting periods. Dried bu-ja whish was treated with alkaline solutions followed by heat treatment has the detoxification index, 50% and dried bu-ja which was treated only with hear has 71. 8%. Compared to the value of index of Japanese 'ka-gong bu-ja', 72%, the dried bu-ja treated with heat at $120^{\circ}$ and 1, 2 lbs for 60min was the most adequate. The $LD_{50}$ value of the processed bu-ja was higher than 15 g crude drugs/kg, p.o. in mice.

• Analytical Science and Technology
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• v.23 no.2
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• pp.172-178
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• 2010

Glutathione S-transferase is known to play a crucial role in detoxification in many cases. To develop a herbicide detection biosensor, we in this study attempted to immobilize glutathione S-transferase enzyme on solid supports, polystyrene and agarose, and Na-alginate. These matrixes were attractive materials for the construction of biosensors and might also have utility for the production of immobilized enzyme bioreactors. We also compared the activities of glutathione-S-transferase immobilized OsGSTF3 and free OsGSTF3. The specific activity of the free enzyme in solution was 3.3 higher than the immobilized enzyme. These results suggest that 50% of the enzyme was bound with the catalytic site in polystyrene-alkylamine bead and immobilized enzymes showed 80% remaining activity until 3 times reuse.

• Korean Journal of Veterinary Service
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• v.35 no.3
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• pp.197-205
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• 2012

Despite of a long history of the sulfur on the disease healing effect, there were limited ways of applying sulfur to animal and human. We have developed the detoxified sulfur (non toxic sulfur) method to make it practical and mass production possible through laboring for many years. This study practiced scanning electron microscope (SEM), Energy dispersive X-ray spectrometer (EDS) and secondary ion mass spectrometry (SIMS) analysis to investigate the physicochemical aspect of detoxified sulfur. We also performed the oral toxicity experiment to mice, and anti-bacterial test of the detoxified sulfur. Based on the SEM, EDS and SIMS results, the united particles in the mass form with the similar component intensity with the raw sulfur were observed, and hydrogen sulfide ion (HS-) component which is regarded as a toxic matter, was decreased after detoxification. Indeed, toxicity test on the mice (10 males, 10 females) showed no clinical, histopathological changes with the 5 times amount (2,500 mg/kg) of the actual doses. However, the male-mice showed decreased in body weight by 23.6%, 24.3% in the 7th, 14th day, respectively, after detoxified sulfur. Moreover, the female-mice administered the detoxified sulfur showed decreased in body weight by 28.7% (P<0.05) than that in the control group on the 14th day. The result of antibacterial test on the detoxified sulfur showed antibacterial effect (27%) to inhibit the growth of Staphylococcus aureus. It is shown that detoxified sulfur can be used as feed additive and has an affect on the farm perfomance.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.1943-1950
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• 2016

Polycyclic aromatic hydrocarbons (PAHs) are commonly present xenobiotics in natural and contaminated soils. We studied three (phenanthrene, naphthalene, and biphenyl) xenobiotics, catabolism, and associated proteins in Sphingobium chungbukense DJ77 by two-dimensional gel electrophoresis (2-DE) analysis. Comparative analysis of the growth-dependent 2-DE results revealed that the intensity of 10 protein spots changed identically upon exposure to the three xenobiotics. Among the upregulated proteins, five protein spots, which were putative dehydrogenase, dioxygenase, and hydrolase and involved in the catabolic pathway of xenobiotic degradation, were induced. Identification of these major multifunctional proteins allowed us to map the multiple catabolic pathway for phenanthrene, naphthalene, and biphenyl degradation. A part of the initial diverse catabolism was converged into the catechol degradation branch. Detection of intermediates from 2,3-dihydroxy-biphenyl degradation to pyruvate and acetyl-CoA production by LC/MS analysis showed that ring-cleavage products of PAHs entered the tricarboxylic acid cycle, and were mineralized in S. chungbukense DJ77. These results suggest that S. chungbukense DJ77 completely degrades a broad range of PAHs via a multiple catabolic pathway.

• Journal of Periodontal and Implant Science
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• v.37 no.2
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• pp.251-263
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• 2007

The present study was performed to evaluate the effects of Tetracycline-HCI on the microstructure change of SLA implant surface according to application time. In the Tetracycline-HCI group, 6 implants were rubbed with sponges soaked $50mg/m{\ell}$ Tetracycline-HCI solution for O.5min., lmin., 1. 5min., 2min., 2.5min. and 3min. In the saline group. another 6 implants conditioned with sponges soaked saline using same methods. One implant wasn't conditioned anything. Then, the changes of surface roughness values were evaluated by optical interferometer & specimens were processed for scanning electron microscopic observation. The results of this study were as follows: 1. In both Tetracycline-HCI group & saline group, there are no significant differences between surface roughness values before & after surface detoxification. And in scanning electron microscopic observation. there are slightly changes of implant surface structures but this changes were not significant by comparison with no treatment implant surface. 2. In the changes of surface roughness values & the scanning electron microscopic observation, there were no significant differences between saline & Tetracycline-HCI groups. In conclusion, the detoxification with $50mg/m{\ell}$ Tetracycline-HCI within 3 minutes can be applied for treatment of peri-implantitis in SLA surface implants. without surface microstructure changes.

• Journal of Periodontal and Implant Science
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• v.37 no.2
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• pp.265-275
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• 2007

The present study was performed to evaluate the effect of Tetracycline-HCI on the change of implant surface microstructure according to application time. Implants with thermal dual acid etched surface were utilized. Implant surface was rubbed with $50mg/m{\ell}$ Tetracycline-HCI solution and sterilized saline for O.5min, 1min, 1.5min, 2min, 2.5min and 3min. respectively in the test group. Then, specimens were processed for scanning electron microscopic observation and measured surface roughness by optical interferometer. The results of this study were as follows. 1. The thermal dual acid etched surfaces showed many small peaks and valleys distributed overall surface. 2. The surface conditioning with Tetracycline-HCI and saline didn't influence on its micromorphology. In conclusion, the implant with thermal dual acid etched surface has a protective micromorphology from the detoxification with $50mg/m{\ell}$ Tetracycline-HCI and a scrubbing with cotton pellet. Therefore, the detoxification with $50mg/m{\ell}$ Tetracycline-HCI is an effective method for peri-implantitis in case implants with thermal dual acid etched surface.