• Journal of Microbiology and Biotechnology
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• 제23권5호
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• pp.661-667
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• 2013

Lipase-producing bacterial strains were isolated from Antarctic soil samples using the tricaprylin agar plate method. Seven strains with relatively strong lipase activities were selected. All of them turned out to be Bacillus pumilus strains by the 16S rRNA gene sequence analysis. Their corresponding lipase genes were cloned, sequenced, and compared. Finally, three different Bacillus pumilus lipases (BPL1, BPL2, and BPL3) were chosen. Their amino acid sequence identities were in the range of 92-98% with the previous Bacillus pumilus lipases. Their optimum temperatures and pHs were measured to be $40^{\circ}C$ and pH 9. Lipase BPL1 and lipase BPL2 were stable up to $30^{\circ}C$, whereas lipase BPL3 was stable up to $20^{\circ}C$. Lipase BPL2 was stable within a pH range of 6-10, whereas lipase BPL1 and lipase BPL3 were stable within a pH range of 5-11, showing strong alkaline tolerance. All these lipases exhibited high hydrolytic activity toward p-nitrophenyl caprylate ($C_8$). In addition, lipase BPL1 showed high hydrolytic activity toward tributyrin, whereas lipase BPL2 and lipase BPL3 hydrolyzed tricaprylin and castor oil preferentially. These results demonstrated that the three Antarctic Bacillus lipases were alkaliphilic and had a substrate preference toward short- and medium-chain triglycerides. These Antarctic Bacillus lipases might be used in detergent and food industries.

• 생물환경조절학회지
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• 제16권3호
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• pp.252-257
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• 2007

전남 서남부지역의 참다래 과수원에서 발생하는 과숙썩음병원균(fruit rot, Botryosphaeria dothidea)에 대한 항균작용이 우수한 세균성 균주를 선발하기 위하여 참다래 과수원 토양으로부터 단일균주를 분리하였으며, 과숙썩음병원균(Botryosphaeria dothidea)에 대한 생물적 제어 능력을 검정하고 균주 동정을 실시하였다. 참다래 과수원에서 분리한 총 250여종의 단일균주 중에서 참다래에서 발생하는 과숙척음병원균에 대하여 길항작용이 우수한 균주를 1차적으로 6종 선발하였고, 이 중에서 참다래 과숙썩음병원균에 대하여 길항 작용이 96.0% 정도로 우수한 Strain #120을 최종적으로 선발하였다. 길항균 #120의 포자배열은 rectiflexibles 하였고, 포자표면은 smooth형이었으며, 분리균 세포벽내 LL-type이 DAP를 갖는 wall chemotype I 이었다. 길항균 #120의 균주 형태학적 특성, 생리 생화학적 그리고 화학 분류학적 특성 등을 종합하여 볼 때 길항균 #120은 Streptomyces sp. #120으로 동정되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1336-1342
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• 2005

The present research work was conducted to evaluate the beneficial effects as well as the safety aspects of lactobacilli as probiotic. Lactobacilli were isolated from poultry faecal samples, feed samples and from some known preparations procured from poultry feed manufacturers. L. acidophilus and L. sporogenes were tested for the antibacterial activity against four poultry pathogens viz. Escherichia coli, Salmonella spp., Proteus spp. and Pseudomonas aeruginosa. Cell free supernatant (CFS) of L. acidophilus exhibited significantly higher antibacterial activity against Salmonella spp. at original pH (4.50${\pm}$0.02). At the adjusted pH (6.50${\pm}$0.02) significantly higher antibacterial activity was recorded against indicator organism except for P. aeruginosa. Likewise, L. sporogenes exhibited similar antibacterial activity at original as well as adjusted pH except for E. coli. Antibacterial activity against E. coli was significantly higher at adjusted pH than at original pH of CFS. The competitive exclusion of E. coli by lactobacilli over the intestinal epithelial cells (IEC) was checked. L. acidophilus strain I, which was of poultry origin, exhibited maximum attachment over IEC as compared to other three strains of non-poultry origin viz. L. acidophilus strain II, L. sporogenes strain I and II. Overall, L. acidophilus exhibited higher competitive exclusion as compared to L. sporogenes. All the lactobacilli of poultry origin were most sensitive to penicillin G, amoxycillin, ampicillin and chloramphenicol, least sensitive to sulphamethizole, ciprofloxacin, neomycin, norfloxacin and pefloxacin and resistant to metronidazole and nalidixic acid. The isolates from probiotic preparations were most sensitive to ampicillin, amoxycillin and tetracycline, least sensitive to sulphamethizole, norfloxacin, neomycin and ceftriazone and resistant to nalidixic acid and metronidazole. Eight of the multiple drug resistant lactobacilli isolates were studied for the presence of plasmids. Plasmids could be extracted from six isolates of lactobacilli. These plasmids could be responsible for bacteriocin production or for antibiotic resistance of the strains. The lactobacilli need further studies regarding their safety for use in the probiotic preparations.

• 한국미생물·생명공학회지
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• 제37권3호
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• pp.219-225
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• 2009

본 연구는 해양유래의 특이색소미생물을 선발하여 미생물의 특성 및 이차대사산물의 생리활성 탐색을 통해 새로운 생물자원개발을 위해 수행되었다. 본 연구에 사용된 prodigiosin 유사 색소를 생산하는 균주 JE-34는 동중국해 퇴적층으로부터 분리되었으며 Zooshikella sp. JE-34으로 명명하였다. Zooshikella sp. JE-34는 적색색소를 다량 생산하였으며 대표적인 prodigiosin 생산균주인 Serratia marcscens의 색소추출액과 분광학적 특성 및 HPLC 분석을 통해 JE-34가 생산하는 색소가 prodigiosin 유사색소로 판단되었다. JE-34 균주의 배지조성에 따른 생육도 및 pigment 생합성의 변화를 알아보기 위해 탄소원, 질소원, 무기염류를 첨가하며 배양한 결과 탄소원으로는 soluble starch, 질 소원으로는 malt extract, 무기염류로는 $Na_2HPO_4$에서 최적의 pigment를 생산하였다. Zooshikella sp. JE-34는 prodigiosin의 생합성에 있어 대표적인 생산자인 Serratia marcscens와 마찬가지로 우수한 pigment 생합성량을 보여 prodigiosin의 생합성의 생물자원으로서 의의가 있다고 사료된다.

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.93-104
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• 2011

Two hepcidin paralogs (ojhamp1 and ojhamp2) were isolated and characterized from a euryhaline Javanese ricefish (Oryzias javanicus: Beloniformes). The ojhamp1 cDNA encoded 90 or 91 amino acids (aa) of a typical HAMP1 preproprotein. This preproprotein is believed to cleave and yield the 66 or 67 aa-proprotein, followed by the 26 aa-mature peptide, composed of 8 conserved cysteine residues and the QSHL amino terminal motif. The ojhamp2 cDNA encoded 89 aa of HAMP2 preproprotein, cleaved to yield a 65 aa proprotein, and subsequently the 25 aa-mature peptide. The mature OJHAMP1 possessed a cationic isoelectric point (pI), whereas OJHAMP2 had an anionic charge. At the genomic level, both ojhamp1 and ojhamp2 share a conserved tripartite structure (three exons interrupted by two introns) with other vertebrate hepcidin genes. However, the ojhamp1 was shown to exist as two distinct mRNA species, encoding 90 or 91 aa, due to alternative splicing at the junction site between intron I and exon II. Both ojhamp1 and ojhamp2 transcripts were detected in a wide range of tissue types with varying levels of basal expression, although the highest expression was observed in the liver for both isoforms. Transcriptional response to bacterial challenge using Edwardsiella tarda showed that ojhamp1 was moderately upregulated in the liver but remained unchanged in the kidney. However, the ojhamp2 was significantly suppressed in both the kidney and liver, suggesting a potential diversification between the two paralogs.

• 한국임상수의학회지
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• 제28권1호
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• pp.1-6
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• 2011

천연물 오배자 추출물은 in vitro 선행 연구를 통하여 병원성 세균과 바이러스에 대한 강력한 항균 항바이러스 효과를 확인하였다. 본 연구는 양돈 농장에서 130일간의 장기 임상시험을 통하여 효능평가를 통한 천연물 오배자 추출물의 항균 항바이러스 효과를 규명하고자 수행되었다. 200 마리의 돼지를 천연물 오배자 추출물 투여군과 비투여군으로 2 그룹으로 나누어 130일 동안 양돈농장에서 연구가 수행되었다. 천연물 오배자 추출물 투여군에는 항생제가 없는 사료에 천연물 오배자 추출물을 0.2% 배합하여 급여하였고 비투여군은 항생제가 포함된 일반 사료를 급여하였다. 연구기간 동안 사료섭취량, 체중, 임상증상을 분석하고 시험종료일에 부검하여 육안검사와 미생물학적 검사 및 병리조직학적 검사를 수행하였다. 연구결과 천연물 오배자 추출물은 양돈 산업에서 심각한 문제가 되고 있는 병원성 세균과 바이러스에 대한 강력한 항균 항바이러스 효과를 가지고 있는 것을 확인할 수 있었다.

• 한국동물위생학회지
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• 제29권3호
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• pp.277-285
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• 2006

Plasmids are covalently closed circular molecules of DNA that are stably inherited and replicate somewhat independently of the bacterial chromosome. Genes carried on plasmids can mediate a wide variety of important functions, including antibiotics (R plasmids) and heavy metals resistance, toxins production, cell penetration, iron chelation, complement resistance, and metabolic characteristics such as sucrose and lactose fermentation. Fifty strains of lactobacilli were isolated from 26 staters and 29 fermented milk products. They were classified 27 strains as Lactobacillus paracasei subsp paracasei, 11 stains as Lactococcus lactis subsp cremoris, 6 strains as L delbrueckii subsp lactis, 4 strains as L acidophius, and 2 strains as L delbrueckii subsp bulgaricus. All of these strains were examined for drug resistance and transferability of R plasmids. All of the isolates were sensitive to Am, C, CF, E, NB, P, T, and Te. But resistant to SXT 94% (47 strains), K 66% (33 strains), S 56% (28 strains), ENR 50% (25 strains), NOR 38% (19 strains) CIP 38% (19 strains), GM 16% (8 strains), and N 14% (7 strains), in order. And 32 different resistant patterns were found. The most frequently encountered patterns were CIP-ENR-K-NOR-S-SXT (5 strains). In vitro R plasmids transfer experiment, 57 antibiotic resistant strains which were not transfer to the recipient 2 Escherichia coli strains by conjugation, These results indicate that Lactobacillus in internal trade market' stater recognize R factor but transmissible R plasmid is not existed.

• 대한수의학회지
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• 제51권1호
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• pp.29-35
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• 2011

Lack of hygiene and puerperal mastitis are common causes of bacterial diseases in nursing neonates. The aim of this study was to isolate microorganisms from milk samples of healthy female Jindo dogs with suckling puppies and to investigate antimicrobial susceptibility against the isolated bacteria. Milk samples were collected from 120 udders of 12 lactating Jindo dogs that were 2~4 years old without any clinical diseases including mastitis. Bacteria were isolated from 64 milk samples (53.3%), either singly (76.6%) or in combination (23.4%). Staphylococcus (S.) spp. was the most common microorganisms (74.7%) isolated from canine milk, followed by Haemophillus spp. (10.9%), Streptococcus spp. (9.6%), Gardnerella spp. (2.4%) and Moraxella spp. (2.4%). The most frequently isolated organism was S. warneri (31.3%). Antimicrobial susceptibility of these bacteria was tested with 17 antimicrobial agents by Kirbyand Bauer standardized disc diffusion method. Results indicated that bacteria isolated from healthy canine milk were mostly susceptible to amoxicillin-clavulanic acid, cephalothin and ceftiofur, but were resistant to erythromycin, neomycin and tetracycline.

• 한국식품저장유통학회지
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• 제13권3호
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• pp.357-362
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• 2006

유자즙액을 이용한 식초생산을 위하여 초산생성능이 우수한 초산균을 재래초로부터 분리, 동정하고 유자식초 제조를 위한 최적 발효조건을 검토하였다. 재래초로부터 분리한 25균주 중 초산 생산균 분리용 배지에서 초산 생성능이 가장 우수한 균주로 최종 선정된 균주는 Acetobacter sp. V-16으로 동정되었다. 이 균주의 유자식초 생산용 액체 배지에서 배양조건을 살펴본 결과, 최적온도는 $30^{\circ}\C$이었으며, 초산생성에 적합한 배지의 조성은 초기산도2%, 알코올 농도 5% 및 유자즙액 30%가 함유된 배지였다. 유자식초 생산 최적조건은 5% 알코올과 유자즙액 30%가 첨가된 배지를 이용하여 $30^{\circ}\C$에서 진탕배양 시 10일 만에 최고 산도인 6.8%에 도달하였다.

• 한국자원식물학회지
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• 제20권2호
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• pp.216-219
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• 2007

Root colonization by a rhizobacterium, Pseudomonas chlororaphis O6, elicited induced systemic resistance (ISR) in the leaves of cucumber plants against fungal and bacterial pathogens. To understand the role of unique genes during strain O6-mediated ISR, a suppressive subtractive hybridization method was undertaken and led to isolation of twenty-five distinct genes. The transcriptional levels of all the genes showed an increase much earlier under O6 treatment than in water control plants only after challenge with pathogen, while no difference detected on the plants without pathogen challenge. This suggests that O6-mediated ISR is associated with the priming phenomenon, an enhanced capacity for the rapid and effective activation of cellular defense responses after challenge inoculation.