• Journal of Life Science
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• v.14 no.1
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• pp.193-197
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• 2004

A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing large patch disease of turfgrass. Six isolates consistently suppressed large patch in turfgrass, and ranged in the spectrum of extracellular enzymes that they expressed. The best disease- suppressing isolate, TBM912, expressed protease, CMCase, and pectinase activity and inhibited the growth of Rhizectonin solani and Betrytis cinerea in vitro. Here we show that this strain also produces an antibiotic that was identified by TLC, SDS-PACE and HPLC analysis as lipopeptide.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.102-103
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• 2002

옥시테트라싸이클린(OTC)은 테트라사이클린계 항균물질로 비브리오병, 지느러미 붉음병, 인린 병, 아가미 썩음병 등과 같은 수산동물 질병 치료에 많이 사용되고 있는 항균제이다. 어류의 질병을 치료하기 위해 투여된 항생제에 대하여 어체내의 잔류농도에 대한 과학적 규명없이 관습적이고 반복적으로 사용되고 있어 과잉투여에 의한 경제적 손실, 과소투여에 의한 내성균의 발현, 양식 어류 체내의 항생물질 잔류 농도등 항생제 사용 문제는 양식산업뿐 아니라 수산가공 입장에서도 매우 중요한 현안으로 대두되고 있다. (중략)

• YAKHAK HOEJI
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• v.45 no.6
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• pp.588-590
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• 2001

Two flavanones, (2S) -2'-methoxykurarinones (1) and kurarinones (2) , were isolated from the ethyl acetate extract of the roots of Sophora flavescense Ait. Their structrures were elucidated using NMR, UV and IR spectral analysis. These compounds exhibited a moderate antimicrobial activities against Staphylococcus aureus, Staphylococcus epidermidis Pseudomonas Putida and a weak anti-fungal activity against Candida albicans.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.240-241
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• 2001

자연계로부터 Vibrio sp.에 항균활성을 갖는 균을 검색하여 분리하고 분리균의 동정결과 Pseudomonas aeruginoso로 동정되었으며, 분리한 균의 항균성 물질의 최적 생산조건을 검토하며, 항균성 물질을 정제하여 그 안정성과 항균작용기작에 대해 조사한 결과 pH와 열에 대한 광범위한 안정성을 보였으며, 항균물질이 V. cholerae non-O1 ATCC 25872 세포에 대해 뚜렷한 용균작용을 하는 것을 관찰하였다.

• Journal of Life Science
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• v.21 no.10
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• pp.1481-1486
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• 2011

Spent mushroom substrate (SMS) is a by-product remained after a crop of mushrooms. About seven thermophilic strains were isolated from SMS (Flammulina velvtipes). Among them, one isolate, designated UJ03, showed the antifungal activity against Aspergillus flavus and Aspergillus ochraceous producing mycotoxin on PDA medium, potentially. The strain UJ03 produced cellulase and xylanase as extracellular hydrolases. The strain UJ03 was identified as a member of the genus Bacillus by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain UJ03 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus amyloliquefaciens with sequence similarity of 98.9%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain UJ03 was classified within the genus Bacillus, for which the name Bacillus sp. UJ03 is proposed. The antifungal compound from Bacillus sp. UJ03 was similar to lipopeptide iturin A of Bacillus sp.

• Journal of Veterinary Clinics
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• v.8 no.1
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• pp.59-63
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• 1991

For the purpose of effective therapy and prevention of post weaning E. coli diarrhea, Enrofloxacin-(Baytril premix) was administered in the feed and a series of investigations were made the occurence of diarrhea, weight gain, feed conversion rate, changes In the counts of faecal E. coli and susceptibility of the isolated E. coli strains to antimicrobials. The results obtained were as follows 1. The weaned piglets which were treated with Baytril premix gained the average body weight of 3.2kg over the control group at the age of 62 days. The result indicates a marked weight gain effect which, by statiscal analysis, showed a significant difference(P<0.01). Administration of Baytril premix also resulted in the improvement of feed conversion rate and provention of post weaning diarrhea. 2. The counts of faecal E. coli in Baytri premx treated piglets showed a marked decrease from 3.14${\times}$10$\^$8/cells/g to 2${\times}$10$\^$7/cells/g at 5days post treatment and 1${\times}$10$\^$5/cells/g at 10 days post treatment. 3. 10 strains of E. coli isolated fred the experimental pig farm were highly susceptible to Bayoil, gentamicin and trimethoprim plus sulfamethoxazole.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.1017-1020
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• 2010

최근 국산 농산물의 수요급증과 더불어 소비자들은 안전한 제품의 요구가 높아지고 있다. 이러한 요구에 맞는 제품 개발의 일환으로 미생물 제어가 된 고춧가루 포장제품의 품질향상을 위한 천연항균 물질 소재를 탐색하여 제품개발에 응용하였다. 천연물과 한방재료 중 고춧가루 제품에 적합한 소재를 스크리닝하여 항균물질을 탐색하였으며 고춧가루 제품 패킹에 응용하였다. 천연물 항균제의 개발 원칙은 산취 등 이취가 없어야 하며, 제품에 응용할 수 있는 용해성이나 믹싱의 효과를 높이도록 공정을 최적화 하였다. 또한 최종 천연물 항균제의 형태는 분말 형태로 개발하였다. 천연물에 대한 항균활성은 paper disk test를 통하여 비교하였으며, 항균력이 가장 우수한 소재는 황금추출물이었다. 또한 이들 추출물과 비타민 $B_1$ 인산염의 영향을 함께 비교하였다. 이 천연물 소재 추출물로 개발한 항균물질에 대한 효과는 일반세균, 대장균 검사를 실시하였다. 제품의 안정성 확보 및 유통기한 연장 가능성을 실험한 결과, 일반세균은 $1.0{\times}10^5$cfu/g, 대장균군은 $1.0{\times}10^2$cfu/g, 대장균은 불검출 되었다. 이들 추출물의 항균제 개발과 더불어 다양한 식품에 천연물 항균제로서의 적용 가능성을 모색하고자 하며, 안전한 천연 항균제 개발에 대한 기초 자료를 제공하는 기초 연구를 하고자 하였다.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.133-142
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• 2017

Two hundred bacilli were isolated from rice straw, and 3 strains showing strong inhibitory activities against Bacillus cereus ATCC14579 were selected for further analyses. RSC15 was identified as B. licheniforms, and RSC26 and RSC42 were identified as B. amyloliquefaciens by molecular identification methods. The inhibitory activities were heat stable, and half of the activity was retained for 20 min at $100^{\circ}C$. SDS-PAGE analyses of the culture supernatant indicated that 2 different kinds of antibacterial substances were present with sizes below 3.5 kDa. Antibacterial substances produced by B. licheniformis RSC15 were partially purified by column chromatography, and the specific activity increased from 955.0 AU/mg to 6,400 AU/mg.

• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.182-185
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• 2005

Bioassay-guided isolation of the dried roots of Aralia continentalis led to the isolation of (-)-pimara-8(14), 15dien-19-oic acid (continentalic acid) and $(24E)-Stigmasta-5,22-dien-3{\beta}-ol$ (stagmasterol). Their structures were elucidated using $^1H-NMR$, $^{13}C-NMR$, UV and mass spectra analyses. The gram-positive bacterial, including methicilline-resistant (MRSA), were more sensitive to the continentalic acid and stagmasterol than gram-negative bacterial.

• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.176-189
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• 1995

For the development of antibiotics from Korean mushrooms, the biological activities of extracts from 98 species of mushrooms and from 25 mushrooms were tested against 9 different Gram-negative bacteria and 8 fungi, respectively. Fruiting bodies of each mushrooms were extracted with petroleum ether (P), 80% ethanol (E), and distilled water (H) in that order. P, E, or H extracts from 20 mushroom samples exhibited the antibacterial activity against 8 different Gram-negative bacteria containing Klebsiella pneumoniae, selectively. Among the mushroom extracts with antibiotic activity, E extracts of Boletus umbriniporus, Armillariella tabescens, Rhodophyllus sinuatus, and Suillus luteus showed various antibiotic activities against several bacteria. E extracts of Abortiporus biennis, Phellinus gilvus, and Polyporus dispansus are highly active against Salmonella typhi and their minimum inhibitory concentration (MIC) was all $10\;{\mu}g/ml$. E extract of Armillariella tabescens showed the antifungal activity against Trichopyton mentagrophytes, and its MIC was $300\;{\mu}g/ml$.