소택지 (沼澤地) 침전물에 의한 Atrazine 의 호기 및 혐기성 분해

정규혁,노경신 ( Kyu Hyuck Chung,Kyoung Sin Ro ) 한국물환경학회 1996 한국물환경학회지 Vol.12 No.2

We investigated the aerobic and anaerobic biotransformation of atrazine using laboratory -scale batch reactors containing wetland water and sediment. After 38 weeks of anaerobic incubation, atrazine in the water phase dropped from the initial 10 ㎎/L to 4.2㎎/L. In contrast to the aerobic biotransformation, a significant level of hydroxyatrazine was detected in the sample reactors during 38 weeks of anaerobic incubation. Furthermore, a trace amount of a possible deethylhydroxyatrazine was detected in the anaerobic BSM sample reactor. However, none of the dealkylated metabolites were observed. In contrast to the anaerobic condition, atrazine disappeared rather rapidly within 21 days of incubation after 42 days of stationary phase under aerobic conditions. BSM increased the atrazine biotransformation rate under anaerobic conditions, but decreased the rate under aerobic conditions.

영양원 변화가 Kerosene 분해율 및 분해균주 성장에 미치는 영향

정규혁,Chung, Kyu-Hyuck 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.3

Bioremediation is the technology to harness nature's biodegradative capabilities to remove or detoxify pollutions that threaten public health as environmental contaminants. Composting may become one of major bioremediation technologies for treating soils contaminated with petroleum if the fate of contaminants during composting is better understood Most composting research of petroleum was primarily focused on removing contaminant by optimizing composting conditions. Accordingly, laboratory feasibility studies may be useful to establish a realistic basis in co-composting complex substrate such as petroleum hydrocarbons. The purpose of this study was to assess the optimal conditions of kerosene biodegradation following supplementation with nutrient amendments under simulated composting conditions. Although it increased the growth of bacterial consortium, addition of co-substrates 0.5%(w/v) such as acetic acid, citric acid, glucose, and malic acid was not beneficial. Combination of nitrogen and phosphorous source enhanced kerosene biodegradation and reduced VOC evolution. These results showed that kerosene was able to utilize in bioremediation technology.

우리나라 여성의 임신 중 커피 음용 실태와 산모혈 및 제대혈 중 지질치 변화에 미치는 영향

오승민(Seung Min Oh),정규혁(Kyu Hyuck Chung) 대한약학회 1998 약학회지 Vol.42 No.4

To investigate the effect of coffee consumption during pregnancy on serum lipids in maternal and infants` umbilical cord blood, 76 cases of newborn infants and women delivered of a child who had delivered at hospital located in Chung-Ju city from Feb. 1, 1996 to Aug. 31, 1996 were studied. The gestational ages of cases were 37 to 42 weeks and the average maternal ages were 28.3 +/- 4.63 years old without any other medical or obstetric problems. Infants` Apgar scores and birth weights were decreased by above 3 cups per day of coffee consumption during pregnancy. No relationships between coffee consumption during pregnancy and maternal serum lipid levels were observed. However, serum total cholesterol and LDL-cholesterol levels in infants` umbilical cord were significantly increased with increasing coffee consumption during pregnancy. In contrary to coffee consumption, alcohol drinking habits affected maternal serum lipid levels but not serum lipid levels in infants` umbilical cord blood. Coffee consumption during pregnancy increased caffeine concentration in infants` umbilical cord blood. These results suggest that caffeine from maternal consumption of coffee can easily pass to the fetus and significantly affect serum lipids levels in infants` umbilical cord blood rather than those in maternal blood.

Composting에 의한 Kerosene의 중온성 생분해에 관한 연구

정규혁(Kyu Hyuck Chung),권혁구(Hyuk Ku Kwon),이장훈(Jang Hoon Lee) 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.2

As an emerging remediation technology of petroleum-contaminated soil, composting is the biological conversion of organic-waste materials, under controlled conditions, into a hygienic and relatively biostable product that conditions soil and nourishes plants. Initial research on the composting of petroleum was simply focused on reducing contaminant by optimizing composting conditions. Accordingly, we has required criteria to assess scientifically the biodegradation of hazardous chemicals and data to prove the stability of degradative products. The purpose of this study was to assess the bioremediation feasibility of kerosene-contaminated soil and to provide the data to evaluate systemically composting process by laboratory measurement. A number of heterotrophic, gram-positive, non-spore-forming, and facultative anaerobic bacteria related to kerosene-degrading strains were isolated from composting sampling at various temperature. Isolates were identified as Aeromonas, Corynebacterium, Moraxella, Alcaligenes, and Pseudomonas spp. Under bench-scale composting system, kerosene was mostly removed in 64 days. However, studies with ¹⁴C-labelled hexadecane provided significant evidence that 22.4% of the initial 14C-hexadecane was converted to ¹⁴CO₂ in 64 days.

Composting 타당성 조사를 위한 Bench-Scale System

정규혁(Kyu Hyuck Chung),류지성(Ji Sung Ryu) 한국환경보건학회 1998 한국환경보건학회지 Vol.24 No.4

Composting is an emerging remediation technology for soils contaminated with hazardous chemicals. Bench-scale composting system is an essential tool for researchers and engineers to study biochemical pathways for target contaminants and for preliminary feasibility and optimization studies. Sucessiful design and operation of the remediation composting requires careful consideration of numerous factors affecting the process. The factors can be devided into four classes; physical, chemical, biological and thermodynamical factors. Physical factors define the structure of compost matrix. Chemical factors consider the adequacy of substrates and the toxic effects of contaminants on the compost biomass. Biological factors define biodegradability and the biodegradation rate. Careful choice of a composting system with proper thermodynamical properties ensures the optimal thermophilic conditions. Our bench-scale composting system is 10l acrylic composting reactor with 30cm styroform insulation. This system could be enough to raise and maintain the heat generated from degrading organic substrates. The compost temperature, CO₂ generation and VS/NVS were useful as a tool for determining and evaulating the process of composting. We evaluated and selected the best combination of locally available amendments, bulking agents, and soils to be utilized in the composting technology for remediating contaminated soils.

Vanadium yeast 결합체의 항당뇨 효과

박승희(Seung Hee Park),정규혁(Kyu Hyuck Chung) 한국응용약물학회 2001 Biomolecules & Therapeutics(구 응용약물학회지) Vol.9 No.4

N/A Vanadium yeast was prepared by uptaking vanadate in yeast cells. The growth rate of yeast cells was enhanced by 1∼5% glucose. While the growth rate of yeast cells was not significantly affected by YEPD containing less than 1mM vanadate, it was completely inhibited by 2.5 mM vanadate. Vanadium uptake in yeast cells was increased with increasing vanadate concentration in growth medium. Vanadate (Ⅴ) was reduced to vanadyl (Ⅳ) in yeast cells associating with macromolecular compounds in cells. Oral administration of vanadium yeast significantly reduced blood glucose levels of streptozotocin treated rats same as vanadate. Vanadate and vanadium yeast similarly increased glucose oxidation in isolated adipocytes. Therefore, it was suggested that vanadium yeast could have an antidiabetic activity potency similar to that of vanadate.

피레스로이드계 살충제의 MCF7-BUS세포에 대한 에스트로겐 및 항에스트로겐 효과

오승민(Seung Min Oh),정규혁(Kyu Hyuck Chung) 대한약학회 2001 약학회지 Vol.45 No.6

Synthetic pyrethroids are analogs of a natural chemical moiety pyrethrin, derived from the prethrum plant Chrysanthemum. The natural pyrethrin structure has been modified to be highly lipophilic and photostable, creating an effective pesticide and resulting in an increased presence in the environment. Worldwide, they are commonly used insecticides against ticks, mites, mosquitoes, and as treatment for human head lice and scabies. Therefore, human exposure to their compounds in extensive. Several studies on the effects of pyrethroids on thyroid hormone regulation, estrogen and androgen function have been reported and yet little has been done to assess their potential hormonal activities. Among humans, a pyrethroid compound was suggested to be the causal agent for gynecomastia in a group of Haitian men. The reports suggest that some prethroid compounds are capable of disrupting endocrine function. Therefore, we examined estrogenic/antiestrogenic potential of three pyrethroid insecticides, that is permethrin, allethrin and fenvalerate in human breast cancer cell and action mechanism mediated by the estrogen receptor. Fenvalerate skewed weak estrogenic activity but allethrin and permethrin showed no effect. In combination with high levels (10-10M, 10-11M) of 17β-estradiol and three synthetic pyrethroids inhibited cell proliferations in MCF7-BUS cell by 17β-estradiol. Whereas, fenvalerate increased cell proliferative activity at lower level of estradiol (10-l2M, 10-l3M). The relative affinities to the estrogen receptor were observed by allethrin and permethrin treatment, but not by fenvalerate. These results indicated that some of pyrethroid insecticides may modulate estrogen functions in human breast cancer cell. The action mechanisms of estrogen receptor mediated antiestrogenicity by allethrin and permethrin were postulated.

Cytotoxicity evaluation of titanium dioxide nanoparticles at aerosol exposure

Jung Jin Kim(김정진),Kyu-Hyuck Chung(정규혁) 환경독성보건학회 2015 한국독성학회 심포지움 및 학술발표회 Vol.2015 No.10

Vanadium Yeast의 독성저감 효과

박승희(Seung-Hee Park),정규혁(Kyu-Hyuck Chung) 한국환경성돌연변이발암원학회 2001 한국환경성돌연변이·발암원학회지 Vol.21 No.2

Vanadium has been known as environmental polluants resulted from the burning of fossil fuels in nature. It led to toxic responses by prooxidant activitiy, inducing free radicals and the accumulation in the tissues. Recently, there has been growing interest in an essential nutritional requirement of vandium and especially the treatment of diabetes. But because of its strong toxicity, thease chemicals have narrow safety margin. In order to reduce metal toxicity, and increase absorption and biological activities, metal ions such as selenium and chromium were uptaken in yeast cells. In this study, Vanadium yeast was prepared by uptaking vanadate in yeast cells. Vanadate induced hematological and biochmical changes in the experimental rat blood were inhibited by the treatments of vanadium yeast. Lipid peroxidation and catalase activity were significantly increased in kidney and liver after a single intraperitoneal injection of vanadate to rats. However, these observations were apparently reduced in the vanadium yeast treated group. Vanadium amount in blood, kidney and liver after a single intraperitoneal injection of vanadium yeast was significantly reduced than that of vanadate treated group. In conclusion, vanadium yeast uptaken vanadate in yeast cells could reduce toxic<br/> effects of vanadate.

인터넷을 이용한 국내외 생태위해성평가 교육 현황 파악

김용화(Yong-Hwa Kim),정규혁(Kyu-Hyuck Chung),최진희(Jinhee Choi),안광국(Kwang-Guk An),강소영(So-Young Kang),박연정(Yun-Jung Park),김현맥(Hyun-Mac Kim),류지성(Jisung Ryu),윤준헌(Junheon Yoon),최경희(Kyunghee Choi) 환경독성보건학회 2009 환경독성보건학회지 Vol.24 No.4

This internet search was made to collect background information for a short-term training proposal for securing a national critical mass in ecological risk assessment the need of which is drastically increasing in every sector of Korean society due to the advent of new environmental regulations in industrialized countries, such as EU REACH. This study depended mainly on internet search engines and individual home pages of concerned universities, colleges, and organizations involved in short-term training. Out of lecture titles and syllabus of 200 Korean universities, 86 Japanese national universities, and numerous English speaking educational and training institutions in the world, 60 syllabi were selected and analysed for comparison purpose. Conclusion from the analysis is as follows: Firstly, individual component lectures for ecological risk assessment is provided at different departments in Korea, but no lecture is at present given under the sole title of ecological risk assessment. Secondly, several lectures under the title of ecological risk assessment are open in English-speaking industrialized countries. Lectures as well as technical training and field studies are emphasized in those courses. Lecturers from the regulatory authorities are also involved in those courses. Several short-term training courses are also under operation. Thirdly, it was concluded that the difference in the level of education/training in ecological risk assessment is originated from the substantive requirement of ecological risk in the concerned laws and regulations. Therefore, it is suggested that training of domestic man power in this area is urgent to cope with the industrial pressure imposed by the environmental regulations concerned with chemicals/articles import and export from/to industrialized countries and also to upgrade the domestic laws and regulations.