• 한국지하수토양환경학회지:지하수토양환경
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• 제22권5호
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• pp.82-88
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• 2017

Contaminated sediment can be treated in order to reuse the treated sediment. Even though the chemical criteria are satisfied, the treated sediment could still impose toxic effects. Therefore, this study investigated the changes in the ecological toxic effects of the contaminated sediment from the J region in Singapore after treatment. The contaminated sediment was subject to sequential soil washing and thermal treatment, followed by pH neutralization. Toxic effects of the contaminated and treated sediments were determined by using Vibrio fischeri ($Microtox^{(R)}$), Triticum aestivum (wheat), and Eisenia foetida (earthworm). After treatment, the concentrations of total petroleum hydrocarbons and heavy metals were decreased by 98% and 59-93%, respectively, and satisfied the Industrial Maximum Values of the Dutch Standard, which were used as the remedial goal. The bioluminescence reduction of V. fischeri decreased significantly, and the earthworm survival increased from 0% to 90% after treatment. The germination rate increased from $0{\pm}0%$ to $75{\pm}13%$ after treatment, but the treated sediment may need additional treatment such as nutrient addition for better plant growth. Overall, this study showed that the treatment of the contaminated sediment satisfactorily removed mixed contaminants, and this led to reduction in toxic effects, suggesting improved potentials for reuse of the treated sediment.

• The Plant Pathology Journal
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• 제34권1호
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• pp.78-84
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• 2018

Peroxyacetic acid mixture Perosan, composed of peroxyacetic acid, hydrogen peroxide and acetic acid, was evaluated for eco-friendly management of tomato bacterial wilt by Ralstonia pseudosolanacearum. Perosan drastically suppressed in vitro growth of R. pseudosolanacearum in liquid cultures in dose- and incubation time-dependent manners. Higher perosan doses (0.1 and 1%) caused lowered pH and phytotoxicity to detached leaves of two tomato cultivars Cupirang and Benekia 220 in aqueous solution. Treatment with 0.01% of Perosan delayed wilting symptom significantly in the detached leaves of two cultivars inoculated with R. pseudosolanacearum ($10^7cfu/ml$). Soil drenching of 5% Perosan solution in pots caused severe tissue collapse of tomato seedlings at the four-week-old stage of two tomato cultivars. Treatment with 1% Perosan by soil-drenching significantly reduced bacterial wilt in the tomato seedlings of two cultivars. These findings suggest that Perosan treatment can be applied to suppress bacterial wilt during tomato production.

• Journal of Animal Science and Technology
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• 제59권12호
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• pp.25.1-25.7
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• 2017

Background: Rabbit breeding with high performance imported ones would be of benefit for genetic diversity and improvement of performance in domestic rabbit breeds. The rearing of more productive rabbit breeds could be pathway to improve the productivity and reduce the production cost. Maternal nutritional status exert a great influence on reproductive functions of does, which may expand from conception, through gestation and parturition and development of kits to puberty. Methods: Four breeds of rabbit were evaluated for their parturition, weaning and pubertal differences among the rabbit population in Ibadan, Nigeria. The breed consist of Fauve De Bourgogne (FDB), Chinchilla (CHA), British Spot (BS) and New Zealand White (NZW) rabbits. A total of 60 bucks and 360 does consisting of 15 bucks and 90 does per breed were mated in 6 mating cycles, three each of natural mating and artificial insemination. All does were synchronized for estrus with 20 IU pregnant mare serum gonadotropin 48 h prior to mating. The does after parturition were assessed for milk yield (g) and kit survival rate (%) till weaning, weight changes of kits from birth to puberty. At puberty, the pubertal age (days) and weight (g) of the offspring were assessed. Result: Results obtained reveals that British Spot doe had highest milk yield among the breeds which significantly increased growth of kit and weight at weaning in British Spot rabbits. Survival rates of Chinchilla kits were significantly (p < 0.05) higher than Fauve de Bourgogne, British Spot and New Zealand White kits. Puberty attainment of the rabbits indicates that British spot does and Fauve de Bourgogne bucks are early maturing. Conclusion: Chinchilla shows high kit survivability and British spot has highest milk yield among the four breeds of rabbit.

• 한국약용작물학회지
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• 제17권4호
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• pp.266-272
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• 2009

Cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.95), catalyzes the reduction of hydroxycinnamaldehydes to give hydroxycinnamyl alcohols, or "monolignols," the monomeric precursors of lignin. Lignins are important components of cell walls and lignified secondary cell walls play crucial roles in long distance transport of water and nutrients during plant growth and development and in plant defense against biotic and abiotic stresses. Here a cDNA clone containing a CAD gene, named as PgCAD, was isolated from a commercial medicinal plant Panax ginseng. PgCAD is predicted to encode a precursor protein of 177 amino acid residues, and its sequence shares high homology with a number of other plant CADS. The expression of PgCAD in adventitious roots and hairy roots of P. ginseng was analyzed using reverse transcriptase (RT)-PCR under various abiotic stresses such as salt, salicylic acid, wounding and chilling treatment that triggered a significant induction of PgCAD at different time points within 2-48 h post-treatment. This study revealed that PgCAD may help the plants to survive against various abiotic stresses.

• 생약학회지
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• 제24권2호
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• pp.116-123
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• 1993

The genus Ganoderma is typical wood-rotting fungi and its fruiting body has been used as an important herb in oriental medicine. Recent research discovered antitumor components from Ganoderma lncidum. Various Ganoderma species are being cultivated in Korea. However, taxonomic system of the genus Ganoderma has been based mainly on the macromorphology of fruiting bodies and the ultrastructural characteristics of basidiospores. Since there are similar characteristics in Ganoderma mycelia grown on the same artificial media, it is suggested that the compatibility of the fungi by di-mon mating be used as an aid to determine the identity of species in addition to the conventional characterization. In this study, we examined physiological and genetical properties such as growth temperature, pH, compatibility and enzyme or protein patterns of laccase, esterase and cellular proteins of G. lucidum RZ, G. tsugae and Ganoderma species cultivated in Korea by electrophoresis for characterization of the isolates. We found that compatibility test and isozyme patterns of laccase and esterase of the mycelia could be used for the differentiation of the isolates. These results showed that Ganoderma species cultivated in Korea is genetically similar to G. lucidum but physiologically closer to G. tsugae than to G. lucidum.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.758-761
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• 2001

In this study, the nar promoter of E. coli was characterized to see whether the nar promoter cloned onto pBBR122 can be used as an expression promoter of gram negative microbes. For this purpose, a plasmid with lacZ gene expressing ${\beta}-galactosidase$ instead of the structural genes of nar operon in a gram negative host strain(Agrobacterium.tumefaciens) was used to simplify an assay of induction of the nar promoter. The following effects were investigated to find optimal conditions: methods of inducing the nar promoter, optimal nitrate concentration, maximally inducing the nar promoter, the amount of expressed ${\beta}-galactosidase$ and induction ratio(specific ${\beta}-galactosidase$ activity after maximal induction/specific ${\beta}-galactosidase$ activity before induction). The following results were obtained from the experiments: the growth of Agrobacterium with E.coli nar promoter was not much affected by nitrate concentration in the shake-flask; induction of nar promoter was optimal when Agrobacterium was grown in the presence of 1% nitrate ion at the beginning of culture and when overnight culture was completely grown in the shake-flask before being transferred to other shake-flask; the amount of ${\beta}-galactosidase$ per cell and per medium volume was maximal when Agrobacterium was grown under aerobic condition to $OD_{600}$ of 1.7; then the nar promoter was induced under microaerobic and anaerobic condition made by lowering dissolved oxygen level(DO). After 2-3h of induction in the YEP medium selected as a main culture medium, the specific ${\beta}-galactosidase$ activity became about 17,000 Miller units in the fermentor cluture.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.100.1-100
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• 2003

A dctA gene encoding a protein with identity to a C4-dicarboxylate/H+ was cloned from a beneficial biocontrol bacterium, P. chororaphis O6. Expression of the dctA was induced in minimal medium by several organic acids and was repressed by glucose. Highest expression was observed in early-log cells grown on fumarate and succinate with decline as cells approached late-log phase. The dctA transcript accumulated weakly when cells were grown on malate but strong expression was observed with benzoate. Expression of the dctA transcript was repressed in early-log cells upon addition of glucose to fumarate, but was detected as the cell culture aged. A dctA-deficient mutant of O6, constructed by marker exchange mutagenesis, did not grow on minimal medium containing succinate, benzoate, or fumarate, and growth on malate was delayed. The dctA mutant and wild type grew equally on glucose. The dctA mutant on cucumber roots in sterilized potting soil was colonized at levels comparable to those of the wild type, but induction level of disease resistance by the mutant against target leaf spot disease was decreased. These results may indicate that the dctA is essential for utilization of certain organic acids and its expression is controlled by the availability of sugars. In addition, the dctA is not essenitial for cucumber root colonization, but important for induction of disease resistance.

• 한국식물병리학회지
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• 제1권1호
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• pp.17-21
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• 1985

비병원성 Pseudomonas solanacearum을 이용한 담배세균성마름병의 방제가능성이 검토되었다. Nutrient 액체배지 및 토양에서 비병원성균주는 병원성균주보다 생육속도가 빨랐으나 두 균주를 혼합하여 배양할 때 병원성균주에 대한 생육억제효과는 크지 않았다. 비병원성균주의 현탁액에 감수성 담배품종인 BY4의 뿌리를 6시간동안 침지시킨 후 병원성균주에 오염된 토양으로 이식한 결과, 높은 세균성마름병 방제효과를 얻었다. 비병원성균주의 현탁액을 가식상태의 담배에 토양관주하고 24시간 후에 포장으로 이식한 결과 7월 상순까지는 $30\%$이상의 세균성마름병방제효과가 인정되었으나 그 후 방제효과가 급속히 감소되었다.

• 생명과학회지
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• 제14권3호
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• pp.490-495
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• 2004

인산가용화능이 우수한 균주인 Burkholderia sp. DA23과 Klebsiella sp. DA7l-1 두 균주를 사용하여 농도별 아미노산 첨가에 따른 성장 양상과 유리인산 방출량을 조사한 결과, 두 균주의 생육과 인산가용화에 있어 아미노산이 도움이 되는 것으로 나타났다. DA23과 DA7l-1 모두 0.05%와 0.1%의 아미노산을 SM배지에 첨가하여 성장 양상을 확인한 결과 아미노산을 첨가한 배지의 균주가 아미노산을 처리하지 않은 배지의 균주에 비해 높은 세포 밀도 성장을 보여주었다. 인산가용화 균주의 아미노산 첨가의 경우 무처리보다 높은 pH 저하를 보였으며, 또한 아미노산 첨가가 아미노산 무처리구에 비해 2배이상 높은 인산가용화 효과를 보였다. DA7l-1의 아미노산 첨가의 경우는 DA23의 아미노산 첨가보다 아미노산 첨가에 의한 인산가용화 효과가 더 있는 것으로 나타났다. hydroxyapatite와 tri-calcium phosphate 의 인산염 차이에 따른 아미노산 처리 효과는 없었으며, 0.05%의 미량의 농도에서도 인산가용화로의 세포밀도 성장 및 가용화능에 효과를 나타내었다.

• 한국환경과학회지
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• 제6권2호
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• pp.173-182
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• 1997

The bacterial strains, which utilizes 2,4,4'-trichloro-2'-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highestt biodegradation activity was designated as EL-O47R The isolated strain EL-O47R was Identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH4)2SO4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the regradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-O47R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-O47R was moderately grown to Cd(NO3)2, ZnCl2, AgSO4, CuSO4 and HgCl2. This strain was sensitive to rifampicin and kanamycln but resistant to ampicillin, penicillin, tetracyclin and chloramphenlcol. Pseudomonas sp. EL-O47R was grown structurally related com- pounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.