• 미생물학회지
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• 제31권4호
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• pp.306-311
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• 1993

소수성 기질인 progesterone 을 수용성 반응액 속에 용해하기 위하여 사용되는 methanol 이 Rhizopus nigricans 의 성장과 progesterone 의 11.alpha.-hydroxylation 반응에 미치는 영향을 조사하고, 세포막 인지질의 불포화 지방산 함량을 증가시켜 유기용매에 대한 내성을 유도하였다. R. nigricans 의 균사체는 methanol 존재하에서 형태적인 변화를 일으켰으며, 세포막 인지질의 지방산 조성에 변화를 가져와 불포화 지방산, 특히 oleic acid 의 함량이 증가되었다. 세포의 고정화는 유기용매로부터 세포를 보호하여 progesterone 의 11-.alpha.-hydroxylation 율을 증가시켰다. 성장배지에 500.$\mu$g/l의 biotin 을 첨가하였을 때 세포막 인지질의 oleic acid 함랴이 증가되었으며 methanol 에 대한 내성이 증진되어 높은 progesterone 의 11 $\alpha$-hydroxylation 율을 얻을 수 있었다.

• 한국동물위생학회지
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• 제32권1호
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• pp.33-41
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• 2009

In order to develop probiotic strain for pigs, Lactobacillus spp. (527 isolates), Streptococcus spp. (95 isolates) and Bifidobacterium spp. (25 isolates) were isolated from the feces of 35 pigs. These isolates were tested through in vitro experiment such as acid tolerance at pH 2.0 (Lactobacillus spp. and Streptococcus spp.) or pH 3.0 (Bifidobacterium spp.), bile tolerance in MRS broth containing 0.3% (w/v) Oxgall, heat resistance at $70^{\circ}C$ and $80^{\circ}C$ for 5 min, antibiotic resistance, antimicrobial activity against pathogenic bacteria and Caco-2 cell adherence assay. Finally ten most superior strain (5 Lactobacillus spp. strain, 3 Bifidobacterium spp. strain and 2 Streptococcus spp. strain) were selected as potential candidate for probiotic use in pig industry. It could be used as an alternative to antibiotics in feed additives.

• KSBB Journal
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• 제7권1호
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• pp.33-37
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• 1992

Saccharomyces cerevosiae STV89와 Kluyveromyces fragilis CBS 397을 이용한 알콜발효에서 발효온도에 따른 세포내 에탄올 농도와 지방산 함량비율을 분석하여 효모의 에탄올 내성에 영향을 이치는 요인을 밝히고져 하였다. 실험결과 두 균주 모두 발효온도가 낮을수록 최대 세포내 에탄올 농도는 감소한 반면, 불포화지방산 중에서 oleic acid와 linoleic acid의 함량은 증가하였다. 따라서 세포내 에탄올 축적이 감소하면 세포막의 불포화지방산 함량이 증가하여 세포로 부터의 에탄올 확산이 촉진되기 때문에 효모의 에탄올에 대한 내성이 증가되는 것으로 추정된다.

• Journal of Dairy Science and Biotechnology
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• 제37권1호
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• pp.40-48
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• 2019

Bifidobacteria are a prototype probiotic, which normally inhabit the intestinal tract of humans. In the present study, four species of Bifidobacterium isolated from the feces of infants were characterized. The tolerance for acid or bile salt, autoaggregation, and antibiotic resistance of the bacteria were examined. The four species were resistant to low pH, bile salts, and up to 3% bile acid. Autoaggregation rates were as high as 90%. The bacteria were consistently resistant to gentamicin, kanamycin, streptomycin, ciprofloxacin, and nalidixic acid. Due to their tolerance to environmental factors like acid and bile salts, B. longum MG723, B. breve MG729, B. bifidum MG731, and B. animalis subsp. lactis MG741 are potentially valuable as probiotics and may be useful for industrial application.

• 한국작물학회지
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• 제44권2호
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• pp.176-179
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• 1999

Trinexapac-ethyl[ 4-(cyclopropyl- $\alpha$ -hydroxy-methylene)-3,5-dioxocyclohexane carboxylic acid ethylester] is a growth-retardant for plants by inhibiting a key step in biosynthesis of GA. A treatment of trinexapacethyl generally induces a reduction in vegetative growth and also inhibits heading. In addition, the trinexapacethyl was known to enhance the freeze-tolerance in annual bluegrass, however, the mechanism is not known yet. One possible reason for the enhanced freeze-tolerance may be the antifreeze protein known to be accumulated in intercellular space of the leaf during cold acclimation. In order to see the possible in-duction of the synthesis of antifreeze proteins by trinexacpacethyl, the apoplastic proteins extracted from Kentucky bluegrass treated with trinexapacethyl were analyzed by SDS-PAGE and the presence of the antifreeze protein was observed. In addition, western analysis showed the identity of the protein induced by both a cold acclimation and a trinexapacethyl treatment. It appears that an enhanced freeze-tolerance of the turf grass by trinexapacethyl is due to the synthesis and/or accumulation of the antifreeze protein similar to the enhanced freeze tolerance induced by cold acclimation.

• Animal Bioscience
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• 제36권8호
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• pp.1209-1220
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• 2023

Objective: The use of probiotics as an alternative to antibiotics in animal feed has received considerable attention in recent decades. Lactic acid bacteria (LAB) have remarkable functional properties promoting host health and are major microorganisms for probiotic purposes. The aim of this study was to characterize LAB strains of the chicken digestive tract and to determine their functional properties for further use as potential probiotics in poultry. Methods: A total of 2,000 colonies were isolated from the ileum and cecal contents of the chickens based on their phenotypic profiles and followed by a preliminary detection for acid and bile tolerance. The selected 200 LAB isolates with exhibited well-tolerance in acid and bile conditions were then identified by sequencing the 16S rDNA gene, followed by acid and bile tolerance, antimicrobial activity, adhesion to epithelial cells and additional characteristics on the removal of cholesterol. Then, the two probiotic strains (L. ingluviei and L. salivarious) which showed the greatest advantage in vitro testing were selected to assess their efficacy in broiler chickens. Results: It was found that 200 LAB isolates that complied with all measurement criteria belonged to five strains, including L. acidophilus (63 colonies), L. ingluviei (2 colonies), L. reuteri (58 colonies), L. salivarius (72 colonies), and L. saerimneri (5 colonies). We found that the L. ingluviei and L. salivarius can increase the population of LAB and Bifidobacterium spp. while reducing Enterobacteria spp. and Escherichia coli in the cecal content of chickens. Additionally, increased concentrations of valeric acid and short chain fatty acids were also observed. Conclusion: This study indicates that all five Lactobacillus strains isolated from gut contents of chickens are safe and possess probiotic properties, especially L. ingluviei and L. salivarius. Future studies should evaluate the potential for growth improvement in broilers.

• 생명과학회지
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• 제24권2호
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• pp.161-166
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• 2014

신규 프로바이오틱스 균주로서 사용하기 위하여 한국의 염장 발효 생선가공품인 젖갈로부터 Paenibacillus sp. 균주들을 탐색하였다. 이들 균주들 중에서 BCNU 5016은 그람양성균으로 gelatinase와 urease를 생산하지 않는 전형적인 Paenibacillus sp. 균주로 확인되었다. 이 균주는 16S rDNA 염기서열 분석을 바탕으로 계통적으로 Paenibacillus polymyxa의 근연종임이 확인되었다. Paenibacillus sp. BCNU 5016은 내산성 실험을 통해 pH 2.5에서 3h 배양 후에도 91.89%까지 생존함이 확인되었고, 담즙산에도 뛰어난 내성이 있음이 확인되었다. 또한 BCNU 5016은 자가응집능, 공동응집능 및 소수성 능력으로 볼 때 우수한 장점막 부착능력을 가지고 있는 것으로 판단된다. 그러므로 Paenibacillus sp. BCNU 5016은 프로바이오틱스 균주로서 우수한 잠재력을 가지고 있음을 확인할 수 있었다.

• The Plant Pathology Journal
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• 제29권2호
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• pp.209-220
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• 2013

Root colonization by Pseudomonas chlororaphis O6 induces systemic drought tolerance in Arabidopsis thaliana. Microarray analysis was performed using the 22,800-gene Affymetrix GeneChips to identify differentially-expressed genes from plants colonized with or without P. chlororaphis O6 under drought stressed conditions or normal growth conditions. Root colonization in plants grown under regular irrigation condition increased transcript accumulation from genes associated with defense, response to reactive oxygen species, and auxin- and jasmonic acid-responsive genes, but decreased transcription factors associated with ethylene and abscisic acid signaling. The cluster of genes involved in plant disease resistance were up-regulated, but the set of drought signaling response genes were down-regulated in the P. chlororaphis O6-colonized under drought stress plants compared to those of the drought stressed plants without bacterial treatment. Transcripts of the jasmonic acid-marker genes, VSP1 and pdf-1.2, the salicylic acid regulated gene, PR-1, and the ethylene-response gene, HEL, also were up-regulated in plants colonized by P. chlororaphis O6, but differed in their responsiveness to drought stress. These data show how gene expression in plants lacking adequate water can be remarkably influenced by microbial colonization leading to plant protection, and the activation of the plant defense signal pathway induced by root colonization of P. chlororaphis O6 might be a key element for induced systemic tolerance by microbes.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.38-38
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• 2017

Water stress obstructs rice growth mainly by oxidative damage in biological cells to cause a reduction of leaf photosynthesis and evapotranspiration processes. In this study, exogenous application of vanillic acid (VA) and p-hydroxybenzoic acid (PHBA) to improve drought tolerance of two Oryza sativa cultivars, Q2 and Q8 was tested. The drought evaluation based on leaf phenotypes to show that both Q2 and Q8 resulted in remarkable water-stress tolerance induced by leaf spraying pretreatment of mixed solution of $50{\mu}M\;VA+50{\mu}M\;PHBA$. The mixtures of $25{\mu}M\;VA+25{\mu}M\;PHBA$ and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treated on Q2 and Q8 in water deficit condition also indicated that total phenols, total flavonoids, and DPPH radical scavenging activity were significantly greater their controls. In general, the accumulation of individual phenolic acids was increased in exogenous phenolic treatments, as compared with controls. Particularly, Q2 obtained a considerable amount of endogenous PHBA after application of $50{\mu}M\;VA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ (0.18 mg/g DW, 0.71 mg/g DW, and 1.41 mg/g DW, respectively); and a negligible content of VA (0.003 mg/g DW) appeared uniquely in the treatment of $50{\mu}M\;VA$. Similarly, Q8 also absorbed a significant quantity of PHBA in $50{\mu}M\;PHBA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treatments (0.15 mg/g DW, 0.15 mg/g DW, and 0.22 mg/g DW, respectively). In addition, the spraying $50{\mu}M\;PHBA$ and $25{\mu}M\;VA+25{\mu}M\;PHBA$ on Q8 leaves induced similar amount of drought tolerance of Q2 and Q8 were improved, paralleled with the increased amounts of endogenous phenolics revealed that VA and PHBA played an important role to enhance drought tolerance in rice.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.33-33
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• 2017

Water stress obstructs rice growth mainly by oxidative damage in biological cells to cause a reduction of leaf photosynthesis and evapotranspiration processes. In this study, exogenous application of vanillic acid (VA) and p-hydroxybenzoic acid (PHBA) to improve drought tolerance of two Oryza sativa cultivars, Q2 and Q8 was tested. The drought evaluation based on leaf phenotypes to show that both Q2 and Q8 resulted in remarkable water-stress tolerance induced by leaf spraying pretreatment of mixed solution of $50{\mu}M\;VA+50{\mu}M\;PHBA$. The mixtures of $25{\mu}M\;VA+25{\mu}M\;PHBA$ and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treated on Q2 and Q8 in water deficit condition also indicated that total phenols, total flavonoids, and DPPH radical scavenging activity were significantly greater their controls. In general, the accumulation of individual phenolic acids was increased in exogenous phenolic treatments, as compared with controls. Particularly, Q2 obtained a considerable amount of endogenous PHBA after application of $50{\mu}M\;VA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ (0.18 mg/g DW, 0.71 mg/g DW, and 1.41 mg/g DW, respectively); and a negligible content of VA (0.003 mg/g DW) appeared uniquely in the treatment of $50{\mu}M\;VA$. Similarly, Q8 also absorbed a significant quantity of PHBA in $50{\mu}M\;PHBA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treatments (0.15 mg/g DW, 0.15 mg/g DW, and 0.22 mg/g DW, respectively). In addition, the spraying $50{\mu}M\;PHBA$ and $25{\mu}M\;VA+25{\mu}M\;PHBA$ on Q8 leaves induced similar amount of VA (0.04 mg/g DW). Meanwhile, there were no trace of VA and PHBA found in controls. The levels of drought tolerance of Q2 and Q8 were improved, paralleled with the increased amounts of endogenous phenolics revealed that VA and PHBA played an important role to enhance drought tolerance in rice.