• The Korean Journal of Physiology and Pharmacology
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• 제16권1호
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• pp.37-42
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• 2012

The aim of the present study was to elucidate the direct effects of melatonin on bladder activity and to determine the mechanisms responsible for the detrusor activity of melatonin in the isolated rat bladder. We evaluated the effects of melatonin on the contractions induced by phenylephrine (PE), acetylcholine (ACh), bethanechol (BCh), KCl, and electrical field stimulation (EFS) in 20 detrusor smooth muscle samples from Sprague-Dawley rats. To determine the mechanisms underlying the inhibitory responses to melatonin, melatonin-pretreated muscle strips were exposed to a calcium channel antagonist (verapamil), three potassium channel blockers [tetraethyl ammonium (TEA), 4-aminopyridine (4-AP), and glibenclamide], a direct voltage-dependent calcium channel opener (Bay K 8644), and a specific calcium/calmodulin-dependent kinase II (CaMKII) inhibitor (KN-93). Melatonin pretreatment ($10^{-8}{\sim}10^{-6}M$) decreased the contractile responses induced by PE ($10^{-9}{\sim}10^{-4}M$) and Ach ($10^{-9}{\sim}10^{-4}M$) in a dose-dependent manner. Melatonin ($10^{-7}M$) also blocked contraction induced by high KCl ($[KCl]_{ECF}$; 35 mM, 70 mM, 105 mM, and 140 mM) and EFS. Melatonin ($10^{-7}M$) potentiated the relaxation response of the strips by verapamil, but other potassium channel blockers did not change melatonin activity. Melatonin pretreatment significantly decreased contractile responses induced by Bay K 8644 ($10^{-11}{\sim}10^{-7}M$). KN-93 enhanced melatonin-induced relaxation. The present results suggest that melatonin can inhibit bladder smooth muscle contraction through a voltage-dependent, calcium-antagonistic mechanism and through the inhibition of the calmodulin/CaMKII system.

• Journal of Microbiology and Biotechnology
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• 제30권7호
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• pp.1027-1036
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• 2020

Stipa purpurea is a unique and dominant herbaceous plant species in the alpine steppe and meadows on the Qinghai-Tibet Plateau (QTP). In this work, we analyzed the composition and diversity of the culturable endophytic fungi in S. purpurea according to morphological and molecular identification. Then, we investigated the bioactivities of these fungi against plant pathogenic fungi and 1-aminocyclopropane-1-carboxylate deaminase (ACCD) deaminase activities. A total of 323 fungal isolates were first isolated from S. purpurea, and 33 fungal taxa were identified by internal transcribed spacer primers and grouped into Ascomycota. The diversity of endophytic fungi in S. purpurea was significantly higher in roots as compared to leaves. In addition, more than 40% of the endophytic fungi carried the gene encoding for the ACCD gene. The antibiosis assay demonstrated that 29, 35, 28, 37 and 34 isolates (43.9, 53.1, 42.4, 56.1, and 51.5%) were antagonistic to five plant pathogenic fungi, respectively. Our study provided the first assessment of the diversity of culture-depending endophytic fungi of S. purpurea, demonstrated the potential application of ACCD activity and antifungal activities with potential benefits to the host plant, and contributed to high biomass production and adaptation of S. purpurea to an adverse environment.

• 농약과학회지
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• 제16권2호
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• pp.178-186
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• 2012

본 연구는 9종 식물병원균에 대한 항진균 활성을 나타내는 길항세균을 분리하여 동정한 결과 Bacillus subtilis KYS-10로 명명하였고, sucrose 4%, yeast extract 1.0%, $K_2HPO_4$ 0.2%, pH 7의 최적배지에서 150 rpm, $30^{\circ}C$, 8일간 배양 시 가장 좋은 생육을 나타냈다. B. subtilis KYS-10의 9종 식물병원균에 대한 항진균 활성을 확산법에 의해 생육저지환의 크기를 측정한 결과 G. zeae (맥류 붉은곰팡이병) 70 mm로 가장 높았고, 35~39 mm의 생육저해환을 나타낸 식물병원균은 P. KACC 40439(벼도열병), P. capsici KACC 40177(고추역병균), C. destructans KACC 41077(인삼뿌리썩음병) 40~43 mm, C. gloeosporioides KACC 43520(포도 탄저병균), C. gloesporioides KACC 40003(고추 탄저병균), S. shiraiana KACC 41065(상추 균핵병균), S. shiraiana(오디 균핵병균) 있었으며, F. Oxysporum KACC 44452(인삼 부패병균)은 28 mm로 다종의 식물병원균에 대해 높은 저해활성을 보였다. 이상의 결과들은 추후 포장실험을 통하여 친환경 미생물제제로의 개발 가능성을 시사해 주고 있다.

• Journal of Animal Science and Technology
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• 제53권4호
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• pp.341-348
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• 2011

이 연구는 천연소재 probiotics 발효물을 대상으로 가축의 장내 유해세균으로 알려진 S. typhimurium KCTC 2054와 E. coli O157:H7의 생장을 억제시키는 유효 발효물을 선발하여 특성을 연구하는 데 있다. 실험 샘플 444개 중 유해 세균에 대한 항균력이 가장 우수한 것으로 C. butyricum IDCC 9207 백미 발효물(FWR)을 최종 선발하였다. C. butyricum IDCC 9207이 함유된 백미 발효물 (FWRCb9207)을 S. typhimurium KCTC 2054로 감염시킨 ICR-mice에 일정기간 투여하였을 때, salmonella의 생육이 억제됨을 확인하였으며, 장관에서 분비되는 secretory immunoglobulin A (sIgA)의 양이 증가됨을 확인하였다. FWRCb9207은 기존의 생균제 보다 빠른 정장효과를 나타낼 수 있으며, 발효물보다 생균보강을 통해 정장작용의 기간을 늘릴 수 있는 것이 장점이다. 또한 FWRCb9207의 급여를 통해 사료로부터 쉽게 감염되는 S. typhimurium, S. gallinarum, S. pullorum, S. choleraesuis ssp. choleraesuis 등의 유해세균 증식을 효과적으로 억제시키고 면역력을 증진시킴으로써 가축의 증체율을 높였다. 이러한 FWRCb9207의 synbiotic effects는 궁극적으로 기존 항생제를 대체함으로써 항생제 오남용으로 발생되는 문제점을 해소할 수 있을 것으로 기대된다.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1303-1310
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• 2008

Inhibitors of farnesyltransferase (FT), a key enzyme in the post-translational modifications of Ras proteins, have been extensively studied as novel anticancer agents in the preclinical stages, some of which are currently in clinical development. Previously, it has been reported that a novel FT inhibitor LB42907 inhibits Ras farnesylation in the nanomolar range in vitro. The aim of this study was to assess the antitumor efficacy of LB42907 in vitro and in vivo. Anchorage-independent growth of various human tumor cell lines was potently inhibited by treatment with LB42907, comparable to other FT inhibitors in clinical development. In the nude mouse, oral administration of LB42907 demonstrated potent antitumor activity in several human tumor xenograft models including bladder, lung and pancreas origin. Interestingly, significant tumor regression in EJ (bladder) and A549 (lung) xenografts was induced by LB42907 treatment. The effectiveness of LB42907 was also investigated in simultaneous combination with paclitaxel, vincristine, cisplatin or gemcitabine against NCI-H460, A549, and HCT116 cells in vitro using median-effect analysis. LB42907 markedly synergized with most anticancer drugs tested in this study in NCI-H460 cell. In contrast, LB42907 displayed antagonism or partial synergism with these drugs in A549 and HCT116 cells, depending on the class of combined drugs and/ or the level of cytotoxicity. Our results demonstrate that LB42907 is an effective antitumor agent in vitro and in vivo and combination of LB42907 with other chemotherapeutic drugs results in synergistic or antagonistic effects mainly in a cell line-dependent manner. Further preclinical study is warranted.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.13-13
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• 2016

Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

• 생명과학회지
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• 제17권12호
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• pp.1682-1688
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• 2007

다기능성 농업용 미생물 제제를 개발하기 위하여 생물방제 및 생물비료 활성을 가지는 미생물을 탐색하였다. 본 연구실에서 분리 및 동정된 균주가운데 Pantoea agglomerans 및 Bacillus megaterium을 실험군주로 선정하였으며, 경남 밀양에 위치하는 양계장 부근 부엽토로부터 새로운 다목적 세균 MF12를 분리하였다. 형태학적, 배양적, 생화학적 특성 및 16S rDNA 염기서열을 분석한 결과, MF12는 Bacillus pumilis로 동정되었다. 이 균주들의 불용성 인산 가용능, IAA 및 siderophore 생성능, ammonification ability, 식물병원성 진균 세포성분 분해효소 생성능 및 항진균능을 조사하였다. P. agglomerans는 고체배지에서 불용성 인산을 가용화할 수 없었으나 액체배지에서는 가용성 인산을 생성하였다. 상기 모든 균주들은 배양시간에 따라 $3{\sim}639{\mu}g/ml$의 IAA를 생성하였으며, P. agglomerans만이 siderophore를 생성하였다. 이 균주는 pectinase와 lipase를 생성하였다. B. megaterium은 amylase, pretense 및 lipase를 생성한 반면 B. pumilisr는 protease와 lipase를 생성하였다. P. agglomerans는 Fusarium oxysporum과 Colletotrichum gloeosporioides의 생육을 억제하였으며, B. pumilis는 Botrytis cinerea, Sclerotinia sclerotiorum 및 Phythium ultimum의 생육을 억제하였다.

• 미생물학회지
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• 제53권4호
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• pp.242-250
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• 2017

본 연구에서는 경상북도 울릉군에서 분리한 토양 방선균에 대해 생리학적 특징과 다양성에 대해 연구하였다. ULS1 및 ULS2로 명명한 2개의 토양 시료를 채취하여 다양한 배지에 배양하여 분리하였으며, 평균 생균수는 ULS1 토양은 $1.28{\times}10^7CFU/g$, ULS2 토양은 $2.05{\times}10^7CFU/g$였다. 16S rRNA 유전자에 기반한 염기서열 분석 결과, 총 9개의 속에서 34개의 균주가 분리되었으며 해당 속은 Streptomyces (16 균주), Isoptericola (5 균주), Rhodococcus (4 균주), Agromyces (3 균주), Micrococcus (2 균주), Arthrobacter (1 균주), Williamsia (1 균주), Microbacterium (1 균주) 및 Oerskovia (1 균주)에 속하는 것을 알 수 있었다. 다양한 효소활성과 식물 생장 촉진 활성 측정 결과, 전체의 58.8%가 단백질 분해 활성을, 79.4%가 Tween 80 분해 활성을, 그리고 61.8%가 DNA 분해 활성을 각각 가지는 것으로 나타났다. Oerskovia, Williamsia, Isoptericola 및 Streptomyces 속에 속하는 분리주들로부터 인을 가용화시키는 능력을 확인할 수 있었으며, Agromyces, Oerskovia, Micrococcus, Rhodococcus, Streptomyces 및 Isoptericola 속에 속하는 분리주들은 식물호르몬인 3-indole-acetic acid (IAA)를 생산하는 것을 확인할 수 있었다. Streptomyces 속에 속하는 분리주들은 Candida albicans 뿐만 아니라 Staphylococcus aureus와 Bacillus subtilis에 항생활성을 나타내었다. 본 연구는 독특한 생태계를 구성하는 울릉도 지역의 토양 방선균 다양성 및 생리 활성에 대한 최초의 연구로서 의미를 가지며, 새로운 유용 생리 활성 물질의 좋은 원천이 될 것이라 사료된다.

• The Plant Pathology Journal
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• 제33권1호
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• pp.1-8
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• 2017

Seed dehiscence of ginseng (Panax ginseng C. A. Mayer) is affected by moisture, temperature, storage conditions and microbes. Several microbes were isolated from completely dehisced seed coat of ginseng cultivars, Chunpoong and Younpoong at Gumsan, Korea. We investigated the potential of five Talaromyces flavus isolates from the dehiscence of ginseng seed in four traditional stratification facilities. The isolates showed antagonistic activities against fungal plant pathogens, such as Cylindrocarpon destructans, Fusarium oxysporum, Rhizoctonia solani, Sclerotinia nivalis, Botrytis cinerea, and Phytophthora capsici. The dehiscence ratios of ginseng seed increased more than 33% by treatment of T. flavus GG01, GG02, GG04, GG12, and GG23 in comparison to control (28%). Among the treatments, the reformulating treatment of T. flavus isolates GG01 and GG04 showed the highest of stratification ratio of ginseng seed. After 16 weeks, the reformulating treatment of T. flavus isolates GG01 and GG04 significantly enhanced dehiscence of ginseng seed by about 81% compared to the untreated control. The candidate's treatment of T. flavus GG01 and GG04 showed the highest decreasing rate of 93% in seed coat hardness for 112 days in dehiscence period. The results suggested that the pre-inoculation of T. flavus GG01 and GG04 found to be very effective applications in improving dehiscence and germination of ginseng seed.

• 한국작물학회지
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• 제48권
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• pp.58-64
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• 2003

To enjoy a healthy life, it is important to have a well-balanced diet. However, in today's society, there is an increase in the consumption of preprocessed foods and frequency of eating out. Also the western diet, which is becoming move popular worldwide, contains relatively high levels of protein and fat, and a low amount of fiber, Furthermore, the increased availability of favorite foods has created a condition were the individual diet is less variable. With these conditions, it is difficult to maintain a diet that is nutritionally balanced. With these unbalanced diets, which are difficult to change, there has been an increase in adult disease and health problems, such as colon and breast cancer, It is speculated that metabolites for carcinogens are produced from diet components and that intestinal bacteria contribute to the production of these metabolites. Therefore, it is necessary to evaluate the relationships between health, diet, and intestinal microflora. Soybean oligosaccharide is composed of water-soluble saccharides that have been extracted from soybean whey, a by-product from the production of soy protein. This is mainly a mixture of mono-, di-, tri-, and tetrasac-charides, with the principle components being the oligosaccharide raffinose and stachyose. When consumed by humans, the oligosaccharides cannot be digested in the human duodenal and small intestinal mucosa, and these are selectively utilized by beneficial bifidobacteria in intestines. The results of acute and subacute toxicity tests, soy-bean oligosaccharides were nonpoisonous. Soybean oligosaccharides promote the growth of indigenous bifido-bacteria in the colon which by their antagonistic effects, suppress the activity of putrefactive bacteria. Also, they reduce toxic metabolites, detrimental enzymes and plasma lipid, and increase in the frequency of bowel evacuation and fecal quantities. Consequently, soybean oligosaccharides as functional foods components have potential roles in the prevention and medical treatment of chronic adult diseases. The study of processing property and physiological function of soybean oligosacchavides and development of high oligosaccharide variety allow the creation of new and exciting foodstuffs that aye functional healthy.