• 한국약용작물학회지
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• 제13권4호
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• pp.182-185
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• 2005

사람들의 생명연장과 각종 만성질환, 악성종양 등의 증가에 따른 우수한 항생제의 계속적인 개발로 많은 생명을 구할 수 있게 되었지만 반면 항생제를 지나치게 사용하여 이에 많은 부작용이 생기고 내성균도 많아지면서 중증감염이 증가되어 여러 가지의 새로운 문제점에 직면하게 되었다. 안전성이 있는 새로운 항균물질의 개발 목적으로 예비 검색 결과 선택된 독활을 추출하여 컬럼 크로마토그래피를 반복 수행한 결과 2종의 항균 효과를 보여주는 화합물을 분리하였다 이들 화합물은 물리 화학적 성질 및 분광학적 분석을 통하여 화합물 1은 mp가 $166{\sim}167^{\circ}C$인 백색침상, $C_{20}H_{30}O_2$의 분자식을 갖는 (-)-pimara-8(14), 15-dien-19-oic acid 즉, continentalic acld으로 동정하였으며, 화합물 2는 mp가 $164{\sim}165^{\circ}C$인 백색침상, $C_{29}H_{48}O$의 분자식을 갖는 $(24E)-stigmasta-5,\;22-dien-3{\beta}-ol$, 즉 stigmasterol으로 동정하였으며 항균효과를 측정한 결과 두 화합물 모두 유의성 있는 결과를 나타내었으며, 이 중 화합물 1인 continentalic acid이 더욱 우수한 활성을 나타내었다. 특히 그람 양성균인 S. aureus에서 MIC가 $7.8\;{\mu}g/ml$, E. faecalis에서는 MIC가 $12.5\;{\mu}g/ml$에서 비교적 강한 억제 효과를 보였으며, 화합물 2에서는 S. aureus에서 MIC가 $7.8\;{\mu}g/ml$, S. epidemidis에서는 MIC가 $12.5\;{\mu}g/ml$에서 억제 효과를 보여 주었으나 그람 음성균에서 $100\;{\mu}g/ml$ 이상으로 항균활성이 측정되지 않았다. 따라서 화합물 1과 화합물 2는 그람 양성균에 대한 새로운 항균제로 개발에 유용한 화합물이 될 것으로 기대된다.

• 대한수의학회지
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• 제44권1호
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• pp.151-157
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• 2004

Samples of milk were collected from 425 halves of 216 dairy goats in Chonnam province over a period of January through August 2003. Bacterial isolation was carried out on those samples, and their antimicrobial susceptibility was tested. Bacteria were isolated from 166 milk samples (39.1%), either singly (74.7%) or in combination (25.3%). Of the 220 isolates, Staphylococcus spp. was the most prevalent (82.6%), followed by Streptococcus spp. (2.7%), Corynebacterium spp. (1.8%), Enterococcus spp. (1.8%), and Pasteurella spp. (1.8%). Of the 11 species identified from the 182 isolates of Staphylococcus spp., the most frequent species identified were S. epidermidis (28.6%) followed by S. chromogens (14.8%), S. haemolyticus (12.6%), S. aureus (12.1%), S. capitis (8.2%), S. lentus (8.2%), S. hyicus (4.4%), S. simulans (4.4%), S. caprae (2.8%), S. hominis (2.8%) and S. warneri (1.1%). Antimicrobial sensitivity test revealed that most isolates were highly susceptible to 11 antimicrobial agents (96.4 ~ 80.9%), while most isolates were resistant to penicillin.

• Environmental Engineering Research
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• 제25권4호
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• pp.614-621
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• 2020

Antibiotic pollution is one of the factors contributing to the spread of antibiotic-resistant bacteria in the environment. Advanced oxidation and irradiation processes have been introduced to eliminate antibiotics from water and wastewater. However, few studies have reported the toxic effects of residual antibiotics and their byproducts induced by a treatment system. In this study, we compared the efficacies of chemical (high-performance liquid chromatography (HPLC)) and biological (antimicrobial susceptibility test) assays for measuring the concentrations of residual antibiotics after gamma irradiation for degrading amoxicillin, cephradine, lincomycin, and tetracycline. The concentrations of residual antibiotics estimated using the two assay methods were almost identical, except cephradine. In the case of cephradine, inhibited bacterial growth was observed that was equivalent to twice the concentration measured by HPLC in the samples subjected to gamma irradiation. The observed inhibition of bacterial growth suggested the generation of potentially toxic intermediates following antibiotic degradation. These results indicate that biological and chemical assays should be used in concert for monitoring antibiotic contamination and the toxic derivatives of antibiotic degradation. The results demonstrate that these four antibiotics can be decomposed by 2.0 kGy gamma-irradiation without toxic effects of their byproducts.

• 한국작물학회지
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• 제55권4호
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• pp.306-311
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• 2010

저항성원이 다른 7개이 근동질 저항성 계통과 감수성 품종인 Toyonishiki에서 X. oryzae pv. oryzae의 증식과 이동에 관한 시험을 실시하였다. 접종 10일 후, NIL의 접종부위 잎의 세균밀도는 약 $10^5{\sim}10^6\;cfu/cm^2$이었으나 감수성 품종인 Toyonishiki에서는 약 $10^7\;cfu/cm^2$로 높게 나타났다. 이와 같이 감수성 품종에서의 세균 수는 급속히 증가하였으나 NIL에서는 점차적으로 증식하였다. IRBB 103과 Toyonishiki는 접종 25일 후에 접종부위로부터 20cm 위쪽에서 세균이 검출되었으나 다른 NIL에서는 검출되지 않았다. 이와같이 Xa1, Xa4, xa5, Xa7 저항성 유전자는 세균의 이동을 크게 억제하였다.

• Journal of Crop Science and Biotechnology
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• 제10권3호
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• pp.147-158
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• 2007

Xanthomonas axonopodis pv. glycines(Xag) is a pathogen that causes bacterial leaf pustule(BLP) disease in soybeans grown in Korea and the southern United States. Typical and early symptoms of the disease are small, yellow to brown lesions with raised pustules that develop into large necrotic lesions leading to a substantial loss in yield due to premature defoliation. After Xag infects PI 96188, only pustules without chlorotic haloes were observed, indicating the different response to Xag. To identify differentially expressed genes prior to and 24 hr after Xag inoculation to PI 96188 and BLP-resistant SS2-2, an oligonucleotide macroarray was constructed with 100 genes related to disease resistance and metabolism from soybean and Arabidopsis. After cDNAs from each genotype were applied on the oligonucleotide macroarrays with three replicates and dye swapping, 36 and 81 genes were expressed as significantly different between 0 hr and 24 hr in PI 96188 and SS2-2, respectively. Six UniGenes, such as the leucine-rich repeat protein precursor or 14-3-3-like protein, were selected because they down-regulated in PI 96188 and up-regulated in SS2-2 after Xag infection, simultaneously. Using tubulin and cDNA of Jangyeobkong(BLP-susceptible) as controls, the oligonucleotide macroarray data concurred with quantitative real-time RT-PCR(QRT RT-PCR) results in most cases, supporting the accuracy of the oligonucleotide macroarray experiments. Also, QRT RT-PCR data suggested six candidate genes that might be involved in a necrotic response to Xag in PI 96188.

• 대한수의학회지
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• 제56권2호
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• pp.103-108
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• 2016

Salmonellosis is a major bacterial zoonosis that causes self-limited enteritis in animals and foodborne disease and typhoid fever in humans. Recently, multi-drug-resistant strains of Salmonella spp. have increased and caused more serious problems in public health. The present study investigated the antibacterial effects of egg-white lysozyme (EWL) against Salmonella (S.) Typhimurium and the therapeutic effects of EWL for murine salmonellosis. Evaluation of the antibacterial effects of EWL against S. Typhimurium revealed a minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EWL of 6.25 and $300{\mu}g/mL$, respectively. In the bacterial growth inhibition test, EWL at 300 (p < 0.05) and $600{\mu}g/mL$ (p < 0.01) significantly inhibited the growth of S. Typhimurium at 4 h post-incubation. EWL administration at MIC (LYS-1), MBC (LYS-2) and $2{\times}MBC$ (LYS-3) for 14 days resulted in mortality of mice infected with S. Typhimurium of 70, 40 and 10%, respectively, while that of control mice (CON) was 90%. Counts of S. Typhimurium in murine spleens were significantly lower in LYS-2 and LYS-3 than CON (p < 0.05). The results of this study indicate that EWL has the potential for treatment of ICR mice infected with S. Typhimurium.

• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1724-1734
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• 2010

A phosphate-solubilizing bacterial strain isolated from Hippophae rhamnoides rhizosphere was identified as Rahnella sp. based on its phenotypic features and 16S rRNA gene sequence. The bacterial strain showed the growth characteristics of a cold-adapted psychrotroph, with the multiple plant growth-promoting traits of inorganic and organic phosphate solubilization, 1-aminocyclopropane-1-carboxylate-deaminase activity, ammonia generation, and siderophore production. The strain also produced indole-3-acetic acid, indole-3-acetaldehyde, indole-3-acetamide, indole-3-acetonitrile, indole-3-lactic acid, and indole-3-pyruvic acid in tryptophan-supplemented nutrient broth. Gluconic, citric and isocitric acids were the major organic acids detected during tricalcium phosphate solubilization. A rifampicin-resistant mutant of the strain exhibited high rhizosphere competence without disturbance to the resident microbial populations in pea rhizosphere. Seed bacterization with a charcoal-based inoculum significantly increased growth in barley, chickpea, pea, and maize under the controlled environment. Microplot testing of the inoculum at two different locations in pea also showed significant increase in growth and yield. The attributes of cold-tolerance, high rhizosphere competence, and broad-spectrum plant growth-promoting activity exhibited the potential of Rahnella sp. BIHB 783 for increasing agriculture productivity.

• 한국응용곤충학회지
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• 제24권4호
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• pp.219-222
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• 1986

우리나라의 주요(主要) 벼흰잎마름병 저항성(抵抗性) 품종(品種)의 저항성(抵抗性) 유전양식(遺傳樣式)과 저항성(抵抗性) 품종간(品種間)의 대립관계(對立關係)를 분석(分析)하기 위하여 연구(硏究)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. JB8206균주(菌株)에 대(對)한 청청(靑靑)벼, 영풍(永豊)벼, 남풍(南豊)벼, 삼강(三剛)벼, 한강(漢江)찰벼의 흰 잎마름병 저항성(抵抗性)은 1개(個)의 우성유전자(優性遺傳子)에 의(依)해 지배(支配)되었다. 2. JB8206, KN8298균주(菌株)에 대(對)한 백양(白羊)벼와 풍산(豊産)벼의 저항성(抵抗性)은 1개(個)의 우성유전자(優性遺傳子)에 의(依)해 지배(支配) 되었다. 3. JB8206균주(菌株)에 대(對)한 풍산(豊産)벼와 청청(靑靑)벼, 밀양(密陽) 30호(號), 백운(白雲)찰벼의 저항성(抵抗性) 및 수원(水原)312호(號)와 백양(白羊)벼, 백운(白雲)찰벼의 저항성(抵抗性)은 대립관계(對立關係)이었으며 동일유전자(同一遺傳子)로 추정(推定)되었다.

• 한국버섯학회지
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• 제9권3호
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• pp.91-95
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• 2011

느타리버섯은 가장 중요한 식용버섯 중 하나이다. 느타리버섯은 Pseudomonas tolaasii에 의한 세균성 갈변병에 매우 감수성이므로, 저항성 품종을 만들기 위한 노력의 하나로 누에에서 분리된 항 세균성 단백질인 누에신을 느타리버섯에서 과발현시키고자 하였다. 누에신 cDNA는 여름 느타리버섯의 ${\beta}$-tubulin 프로모터에 결합되어 pTRura3-2 vector와 함께 우라실 영양요구성 돌연변이 균주에 형질전환되었다. 누에신 cDNA가 형질전환된 느타리버섯을 genomic PCR과 Southern blot을 통하여 분리할 수가 있었으며, 이들 중 3개의 형질전환체가 누에신 유전자를 발현시킴을 확인하였다. 그러나 이들 형질전환체들에서 누에신 단백질을 검출할 수 없었으며, 또한 항 세균 효과도 확인할 수 없었다. 이들 결과는 형질전환기술을 이용한 병 저항성 개발 가능성을 보여주고 있다.

• International Journal of Oral Biology
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• 제39권2호
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• pp.87-95
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• 2014

The purpose of this study was to isolate and identify bacteria from the 4 patients with non-odontogenic infectious lesions (mucormycosis, chronic inflammation from wound infection, and two actinomycosis) and determine their antimicrobial susceptibility against eight antibiotics. Bacterial culture was performed under three culture conditions (anaerobic, $CO_2$, and aerobic incubator). The bacterial strains were identified by 16S rRNA gene (16S rDNA) sequence comparison analysis method. For investigating the antimicrobial susceptibility of the bacteria against eight antibiotics, penicillin G, amoxicillin, tetracycline, cefuroxime, erythromycin, clindamycin, vancomycin, and Augmentin$^{(R)}$ (amoxicillin + clavulanic acid), minimum inhibitory concentration (MIC) measurement was performed using broth microdilution assay. Nosocomial pathogens such as Enterococcus faecalis, Klebsiella pneumoniae, Bacillus subtilis, and Neisseria flavescens were isolated from mucormycosis. Veillonella parvula, Enterobacter hormaechei, and Acinetobacter calcoaceticus were isolated from chronic inflammatory lesion. Actinomyces massiliensis was isolated from actinomycosis in parotid gland. Capnocytophaga ochracea was isolated from actinomycosis in buccal region in anaerobic condition. There was no susceptible antibiotic to all bacteria in mucormycosis. Tetracycline was susceptible to all bacteria in chronic inflammation. C. ochracea was resistant to vancomycin and penicillin G; and other antibiotics showed susceptibility to all bacteria in actinomycosis. The results indicated that the combined treatment of two or more antibiotics is better than single antibiotic treatment in mucormycosis, and penicillin is the first recommended antibiotic to treat actinomycosis.