• 미생물학회지
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• 제32권2호
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• pp.163-171
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• 1994

경유를 sandy loam 토양에서 농도별로 투여하여 토양미생물군집에 미치는 영향을 조사하였으며 또한 경우가 첨가된 토양에서 경유의 신속한 제거를 위해 실시한 bioremediation에 의한 영향을 측정하였다. 경유는 토양에서 16주 후 약 50% 내외의 잔류량을 나타내며 bioremediation 처리시 제거율은 60~95% 정도가 증가하여 16주 후 약 8~20 범위의 잔류량을 나타내었다. 토양에 경유가 첨가되었을 때에는 세균직접계수, 진균류의 균사 길이, 호기성 종속영양세균과 탄화수소 분해세균의 수가 최고 10 내지 100배 정도 증가하였다. Bioremediation 처리시에는 그 증가가 더욱 두드러져 각종 미생물 개체수 측정치가 최고 100배 내지 1000배까지 증가하였다. 경유가 fluorescein diacetate 가수분해 활성에 미치는 영향은 bioremediation 처리를 하지 않은 토양에서는 뚜렷한 증감의 경향이 없었으나 bioremediation 처리를 한 토양에서는 10배 내외의 활성의 증가를 보였으며 이러한 양상은 soil dehydrogenase 활성에서도 유사하게 나타났다.

• 한국유기농업학회지
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• 제8권1호
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• pp.131-137
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• 1999

This study was conducted to investigate the effects of microbial fertilizers on the yields of Leaf lettuce, chemical components of soil, and the microbial floras. Six micriobial fertilizers, MPK+Husk+Palma, Husk+Palma, MPK+Compost, Compost, Bio livestock cattle system(BLCS) cattle dropping, and Tomi, were used. All of the microbial fertilizers were tend to increase yields of Leaf lettuce, especially MPK+Husk+Palma treatment was most effective. In a chemical components of soil, concentrations of K, Mg were increased with Tomi treatment, however, the other concentrations of soil chemical components were not different. In a microbial floras of soil, Tomi, Husk+Palma, and MPK+Husk+Palma treated plots increased in numbers of total bacteria and bacillus. Tomi treated plot increased in numbers of actinomycetes and fungi, also. The other microbial floras of soil were not different, however. The microbial fertilizers may affect the useful microbial floras, therefore, it would be increase yield of Leaf lettuce treated with them.

• 지질공학
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• 제33권1호
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• pp.15-25
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• 2023

화성암과 퇴적암으로 이루어진 국내 산림토양 중 표토와 심토에서 채취된 시료의 미생물군집 활성도에 미치는 산불의 영향을 알아보았다. 베타글루코시다아제의 분석결과, 화성암보다 퇴적암의 미생물군집에서 높게 나타났다. 산불 발생 초기에 효소 활성이 관찰되지 않았으나, 시간이 경과됨에 따라 활성이 회복되었다. 또한, 토양의 훼손여부와 상관없이 심토는 표토에 비해 활성이 33~46% 저해되었다. EcoPlate를 이용하여 산불이 미생물 기질이용성에 미친 영향을 알아보았다. 정상토와 훼손토의 평균반응구발색도 값 백분율은 표토에서 각각 52.7~56.8% 및 62.3~83.6%로 나타났다. 산불 발생은 토양 유기물의 분해를 촉진함으로 심토미생물군집의 다양성 및 기질이용성에 영향을 준 것으로 보여진다. 미생물군집의 종다양성지수인 샤논 인덱스(Shanon index, H)는 모든 시료의 표토에서 높게 나타났다. 샤논 풍부도는 퇴적암 토양미생물이 화성암에 비하여 높게 나타났으며, 표토가 심토보다 높게 나타났다.

• 생명과학회지
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• 제19권2호
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• pp.206-212
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• 2009

가시상추(Prickly lettuce : Lactuca serriola)로부터 여러 가지 추출용매를 사용하여 생리활성물질을 분리하였다. 가시상추의 일반성분, vitamin, polyphenol성 물질 그리고 flavonoid 성분의 함량을 분석하였다. 또한, MeOH 조추출물에 의한 아질산염 제거 활성, 항산화 활성, 항균 활성을 측정하였다. MeOH 조추출물의 EtOAc 분획에서 가장 높은 아질산염 제거 활성, 항산화 활성 그리고 항균 활성을 보여주었다. 그리고 polyphenol성 물질과 flavonoid의 함량도 가장 높았다. EtOAc 분획 중 subfraction 2 (EtOAc:MeOH=3:1)에서 가장 높은 항산화 활성을 보여주었다. Subfraction 2는 GC-MS에 의해 ${\rho}$-coumaric acid와 caffeic acid로 동정되었다. 가시상추 추출물의 용매 분획별 항균 활성을 검색한 결과, EtOAc 분획에서 가장 높은 항균 활성을 보여주었다. 이러한 연구 결과는 가시상추 유래의 생리활성물질의 생물학적 활성을 이해하는데 필요한 기본 데이터를 제공해 줄 것이다.

• Archives of Pharmacal Research
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• 제15권1호
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• pp.41-47
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• 1992

In order to obtain acetaminophen, a popular analgesic-antipyretic, though microbial p-hydroxylation and N-acetylation of aniline, various Streptomyces strains were screened. Aniline N-acetylation activity was rather ubiquitous but-hydroxylation activity was selective. Microbial conversion pathway of aniline to acetaminophen was considered to be through N-acetylation and p-hydroxylation or vice versa. However, depending on species used, o-hydroxylation and its degradation activity (S. fradiae) and acetaminophen degradation activity (S. coelicolar) were also detected. Among the screened Streptomyces strains, S fradiae NRRL 2702 showed the highest acetanilide p-hydroxylation activity (203% conversion rate). Furthermore, in S. fradiae carbon source and its concentration, phosphate ion concentration and pH of growth medium were found to play the crucial roles in p-hydroxylation activity. Through the proper combination of factors mentioned above, the ten times more activity (26-30% conversion rate) was attained.

• 한국포장학회지
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• 제16권1호
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• pp.5-7
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• 2010

Two kinds of polymer coating (acrylic polymer and vinyl acetate ethylene copolymer) added with 5% nisin were fabricated on the paperboards and tested in their antimicrobial activity against Micrococcus flavus ATCC 10240 inoculated into water contacting the coating at $10^{\circ}C$. Vinyl acetate ethylene copolymer giving faster and higher nisin migration presented the greater reduction in the microbial count than the other coating, which endorsed that the migrated nisin is mainly responsible for the microbial inhibition or destruction. There was also a slight effect of the coating polymer itself in the microbial inhibition.

• The Plant Pathology Journal
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• 제33권5호
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• pp.499-507
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• 2017

In an attempt to develop a biological control agent against mycotoxigenic Fusarium species, we isolated Bacillus amyloliquefaciens strain DA12 from soil and explored its antimicrobial activities. DA12 was active against the growth of mycotoxigenic F. asiaticum, F. graminearum, F. proliferatum, and F. verticillioides both in vitro and in planta (maize). Further screening using dual culture extended the activity range of strain DA12 against other fungal pathogens including Botrytis cinerea, Colletotrichum coccodes, Endothia parasitica, Fusarium oxysporum, Raffaelea quercus-mongolicae, and Rhizoctonia solani. The butanol extract of the culture filtrate of B. amyloliquefaciens DA12 highly inhibited the germination of F. graminearum macroconidia with inhibition rate 83% at a concentration of $31.3{\mu}g/ml$ and 100% at a concentration of $250{\mu}g/ml$. The antifungal metabolite from the butanol extract was identified as iturin A by thin layer chromatography-bioautography. In addition, volatile organic compounds produced by DA12 were able to inhibit mycelial growth of various phytopathogenic fungi. The volatile compounds were identified as 2-heptanone, 5-methyl heptanone and 6-methyl heptanone by gas chromatography-mass spectrometry (GC-MS) analysis. These results indicate that the antagonistic activity of Bacillus amyloliquefaciens DA12 was attributable to iturin A and volatile heptanones, and the strain could be used as a biocontrol agent to reduce the development of Fusarium diseases and mycotoxin contamination of crops.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.265-269
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• 1996

An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

• Journal of Ginseng Research
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• 제3권2호
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• pp.144-155
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• 1979

In order to investigate biochemical effects of ginseng saponin on microbial enzyme activity, Aspergillus oryxae-143 and Aspergillus niger-40, which were selected from various sources of samples and were the highest enzyme producing mold strains, were grown in the medium containing various saponin concentration (0mg%, l0mg%, 50mg%, l00mg%, 150mg% and 300mg%). The enzyme activity (amylase, protease) was found most active when the saponin was added in the culture media with the concentration of l0mg%∼l00mg%. But it seemed that the action of microbial enzyme was inhibited by adding more than 300mg% of saponin.

• 한국가금학회지
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• 제22권2호
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• pp.105-115
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• 1995

The balance of microbial populations in the gastrointestinal (GI) tract of all warm-blooded animals is critical to the maintenance of health and resistance to disease. The composition of the populations can be altered by diet and environment, making the host animal susceptible to disease, and reducing growth rate and feed efficiency. Some feed additives including antimicrobial agents, prohiotics or yucca extract have been used to promote growth and feed utilization. There is evidence that part of growth-promoting effect of those feed additives results from the suppression of microbial urease activity or ammonia production in the GI contents of animals. Over 200 microbial species have been known to produce urease and the product of urea hydrolysis, ammonia, is toxic to animals. Carefully tested probiotics or other urease-suppressing agents can be a possible alternative to antimicrobial agents including antibiotics as growth promotants used for animals feeds.