• 치위생과학회지
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• 제15권2호
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• pp.209-219
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• 2015

치주질환과 관련된 세균인 S. gordonii, F. nucleatum 및 P. gingivalis의 상호작용이 군집 형성에 미치는 영향을 알아보고자 trypticase soy hemin menadione broth에 단독 및 열처리한 사균과 혼합 분주하여 혐기성 균배양조를 통해 $37^{\circ}C$ $CO_2$ 배양기에서 anearobic gas pack 하에 7일간 배양하였다. 군집 형성 정도를 확인하기 위해 흡광도를 측정하였으며, 군집 구조 및 형태를 확인하기 위해 주사전자현미경으로 관찰하였다. P. gingivalis의 병원성에 미치는 영향을 확인하기 위해 real-time RT-PCR를 통해 gingipain인 HRgpA를 생성하는 rgpA 유전자에 대한 발현 분석을 시행하여 다음과 같은 결론을 얻었다. S. gordonii와 P. gingivalis의 군집 형성은 다른 사균들에 의해 증가하였다. F. nucleatum의 경우 P. gingivalis 사균에 의해 증가하는 양상을 보였으나 S. gordonii 사균에 의해서는 군집 형성이 감소되었다. 따라서 본 실험에 사용된 균주는 군집 형성 시 상호작용 인자뿐 아니라 세균 입자 그 자체 등을 통해서도 서로 영향을 주는 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제28권10호
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• pp.1706-1715
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• 2018

Several non-methylotrophic bacteria have been reported to improve the growth and activity of methanotrophs; however, their interactions remain to be elucidated. We investigated the interaction between Methylocystis sp. M6 and Microbacterium sp. NM2. A batch co-culture experiment showed that NM2 markedly increased the biomass and methane removal of M6. qPCR analysis revealed that NM2 enhanced both the growth and methane-monooxygenase gene expression of M6. A fed-batch experiment showed that co-culture was more efficient in removing methane than M6 alone (28.4 vs. $18.8{\mu}mol{\cdot}l^{-1}{\cdot}d^{-1}$), although the biomass levels were similar. A starvation experiment for 21 days showed that M6 population remained stable while NM2 population decreased by 66% in co-culture, but the results were opposite in pure cultures, indicating that M6 may cross-feed growth substrates from NM2. These results indicate that M6 apparently had no negative effect on NM2 when M6 actively proliferated with methane. Interestingly, a batch experiment involving a dialysis membrane indicates that physical proximity between NM2 and M6 is required for such biomass and methane removal enhancement. Collectively, the observed interaction is beneficial to the methanotroph but adversely affects the non-methylotroph; moreover, it requires physical proximity, suggesting a tight association between methanotrophs and non-methylotrophs in natural environments.

• Advances in nano research
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• 제3권2호
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• pp.97-109
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• 2015

Citrate ion is a commonly used reductant in metal colloid synthesis, undergoes strong surface interaction with silver nanocrystallites. The slow crystal growth observed as a result of the interaction between the silver surface and the citrate ion makes this reduction process unique compared to other chemical and radiolytic synthetic methods. The antimicrobial effects of silver (Ag) ion or salts are well known, but the effects of citrate coated Ag nanoparticles (CAgNPs) are scant. Herein, we have isolated biofilm causative bacteria and fungi from drinking water PVC pipe lines. Stable CAgNPs were prepared and the formation of CAgNPs was confirmed by UV-visible spectroscopic analysis and recorded the localized surface plasmon resonance of CAgNPs at 430 nm. Fourier transform infrared spectroscopic analysis revealed C=O and O-H bending vibrations due to organic capping of silver responsible for the reduction and stabilization of the CAgNPs. X-ray diffraction micrograph indicated the face centered cubic structure of the formed CAgNPs, and morphological studies including size (average size 50 nm) were carried out using transmission electron microscopy. The hydrodynamic diameter (60.7 nm) and zeta potential (-27.6 mV) were measured using the dynamic light scattering technique. The antimicrobial activity of CAgNPs was evaluated (in vitro) against the isolated fungi, Gram-negative and Gram-positive bacteria using disc diffusion method and results revealed that CAgNPs with 170ppm concentration are having significant antimicrobial effects against an array of microbes tested.

• Animal Bioscience
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• 제36권5호
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• pp.720-730
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• 2023

Objective: This study investigated the effects of corn silage as a source of microbial inoculant containing antifungal and carboxylesterase-producing bacteria on fermentation, aerobic stability, and nutrient digestibility of fermented total mixed ration (FTMR) with different energy levels. Methods: Corn silage was used as a bacterial source by ensiling for 72 d with an inoculant mixture of Lactobacillus brevis 5M2 and L. buchneri 6M1 at a 1:1 ratio. The corn silage without or with inoculant (CON vs MIX) was mixed with the other ingredients to formulate for low and high energy diets (LOW vs HIGH) for Hanwoo steers. All diets were ensiled into 20 L mini silo (5 kg) for 40 d in quadruplicate. Results: The MIX diets had lower (p<0.05) acid detergent fiber with higher (p<0.05) in vitro digestibilities of dry matter and neutral detergent fiber compared to the CON diets. In terms of fermentation characteristics, the MIX diets had higher (p<0.05) acetate than the CON diets. The MIX diets had extended (p<0.05) lactic acid bacteria growth at 4 to 7 d of aerobic exposure and showed lower (p<0.05) yeast growth at 7 d of aerobic exposure than the CON diets. In terms of rumen fermentation, the MIX diets had higher (p<0.05) total fermentable fraction and total volatile fatty acid, with lower (p<0.05) pH than those of CON diets. The interaction (p = 0.036) between inoculant and diet level was only found in the immediately fermentable fraction, which inoculant was only effective on LOW diets. Conclusion: Application of corn silage with inoculant on FTMR presented an antifungal effect by inhibiting yeast at aerobic exposure and a carboxylesterase effect by improving nutrient digestibility. It also indicated that fermented feedstuffs could be used as microbial source for FTMR. Generally, the interaction between inoculant and diet level had less effect on this FTMR study.

• Journal of Dairy Science and Biotechnology
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• 제18권1호
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• pp.47-60
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• 2000

Over decades of work, the probiotic research has grown rapidly with a number of new cultures, which is claimed a variety of benefit. However, many of the specific effects attributed to the ingestion of probiotics remain convoluted and scientifically unsubstantiated. Accordingly, the scientific community faces a greater challenge and must objectively seek cause and effect relationships for many potential and currently investigated probiotic species. Rational selection and design of probiotics remains an important challenge and will require a solid information about the physiology and genetics of candidate strains relevant to their intestinal roles, functional activities, and interaction of with other resident micro flora. As far as beneficial culture of lactic acid bacteria (LAB) is concerned, simple, cost-effective, and exact identification of candidate strains is of foremost importance among others. Until recently, the relatedness of bacterial isolates has been determined sorely by testing for one or several phenotyphic markers, using methods such as serotyping, phage-typing, biotyping, and so forth. However, there are problems in the use of many of these phenotype-based methods. In contrast, some of newer molecular typing methods involving the analysis of DNA offer many advantages over traditional techniques. These DNA-based methods have the greater discriminatory power than that of phenotypic procedures. This review focuses on the importance and the basis of molecular typing methods along with some considerations on de-sign and selection of probiotic culture for human consumption.

• Journal of Microbiology
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• 제45권5호
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• pp.388-393
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• 2007

Citrus variegated chlorosis (CVC) is a disease of the sweet orange [Citrus sinensis (L.)], which is caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. Sweet orange trees have been occasionally observed to be infected by Xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. The principal endophytic bacterial species isolated from such CVC-asymptomatic citrus plants is Curtobacterium flaccumfaciens. The Madagascar periwinkle [Citrus sinensis (L.)] is a model plant which has been used to study X. fastidiosa in greenhouse environments. In order to characterize the interactions of X. fastidiosa and C. flaccumfaciens, periwinkle plants were inoculated separately with C. flaccumfaciens, X. fastidiosa, and both bacteria together. The number of flowers produced by the plants, the heights of the plants, and the exhibited disease symptoms were evaluated. PCR-primers for C. flaccumfaciens were designed in order to verify the presence of this endophytic bacterium in plant tissue, and to complement an existing assay for X. fastidiosa. These primers were capable of detecting C. flaccumfaciens in the periwinkle in the presence of X. fastidiosa. X. fastidiosa induced stunting and reduced the number of flowers produced by the periwinkle. When C. flaccumfaciens was inoculated together with X. fastidiosa, no stunting was observed. The number of flowers produced by our doubly- inoculated plants was an intermediate between the number produced by the plants inoculated with either of the bacteria separately. Our data indicate that C. flaccumfaciens interacted with X. fastidiosa in C. roseus, and reduced the severity of the disease symptoms induced by X. fastidiosa. Periwinkle is considered to be an excellent experimental system by which the interaction of C. flaccumfaciens and other endophytic bacteria with X. fastidiosa can be studied.

• 한국어병학회지
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• 제13권1호
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• pp.45-51
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• 2000

최근 육상의 넙치 양식장에서는 두 가지의 서로 다른 특성을 가지는 세균성질병이 같이 감염되는 혼합감염증이 빈번하게 발생하고 있는데, 혼합감염증은 서로 다른 원인균의 특성 때문에 단일 종류의 약제만으로는 치료효과를 거두기가 어려운 실정이다. 그러므로 본 연구는 약제의 병용 투여에 의해 이들의 상승작용을 이용함으로써 합병증에 대한 치료효과를 높이기 위한 기초자료를 얻고자 실시하였다. 어류 세균성질병의 원인세균인 Vibrio anguillarum, Edwardsiella tarda, Streptococcus sp., Staphylococcus epidermidis을 선정하여 병용 항균제의 시험관내 활성을 평가하는 대표적 방법인 Checkerboard법을 적용하여 fractional inhibitory concentration (FIC)지수를 구하여 상승효과를 나타내는 병용 항균제를 찾아내었다. (OTC+LM), (TC+FF), (OTC+FF)의 병용 항균제는 V. anguillarum에 대하여, (SNF+FF), (TC+FF), (SNF+OXA), (OTC+FF)의 병용 항균제는 E. tarda에 대하여, (CFX+OL), (OTC+OL), (TC+OL), (OTC+LM), (OTC+SPM), (OTC+EM), (DOXY+OL), (TC+SPM)의 병용 항균제는 Streptococcus sp.에 대하여, (CFX+EM), (FF+EM), (DOXY+OL), (CFX+OL)의 병용 항균제는 S. epidermidis에 대하여 시험관내 상승적 상호작용을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.115-122
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• 2012

Apidaecin Ib had strong antimicrobial activity against several tested Gram-negative bacteria including Escherichia coli, Enterobacter cloacae, and Shigella flexneri (MECs; $0.3-1.5{\mu}g/mL$), but showed no activity against all the tested Gram-positive bacteria including Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus and one yeast, Candida albicans (MECs; > $125{\mu}g/mL$). Interestingly, this peptide showed potent antibacterial activity only against Edwardsiella species (MECs; $0.6-3.6{\mu}g/mL$) among the tested fish pathogenic bacteria through a bacteriostatic process and showed no significant hemolytic activity. Apidaecin Ib took an unordered structure in all environments and also had very weak membrane perturbation activity even at $25{\mu}M$. Anti-Edwardsiella activity of apidaecin Ib is stronger than those of other antimicrobial polypeptides or antibiotics, but its activity is salt-sensitive. These results suggest that apidaecin Ib has Edwardsiella speciesspecific antibacterial activity and could be applied as new preventive or control additives for Edwardsiella species infection in freshwater fish aquaculture.

• 패션비즈니스
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• 제17권6호
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• pp.60-75
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• 2013

This study examined the categories and contents of technology that is recently influencing the fashion design. For this, the cases of global companies integrating fashion design and technology were examined, and the types of technology integration studies within the field of fashion design were analyzed through the trend of fashion-technology integration in domestic academic circles released since 2000. According to the case of global companies integrating fashion design and technology, various companies and fashion brands have released fashion products that are integrated with technology, and such integrations are developing up to the field of fashion shows and displays in addition to fashion products. The analysis of studies related with fashion and technology in the design field showed that domestic studies on fashion-technology integration were manifested as the types that applied various technologies to the fashion design. Such types were categorized into the studies that applied light-emitting technology, studies that focused on the integration of interaction and textile design, studies that applied response-perception, studies that used attached electronic devices, and studies that used autogenic bacteria. The fashion has less negative impact on body and environment compared with other areas, and therefore, is the best area for the experiments in IT, bio, and electronics areas and for the integration of fashion and technology. Moreover, studies on fashion that suggest the capability in developing and industrializing cases through the collaboration with other fields such as IT, bio, and electronics shall continue.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.165-168
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• 2016

Surface protein internalin (InlA) is a major virulence factor of the food-borne pathogen L. monocytogenes. It plays an important role in bacteria crossing the host's barrier by specific interaction with the cell adhesion molecule E-cadherin. Study of this protein will help to find better ways to prevent listeriosis. In this study, a monoclonal antibody against InlA was used to detect InlA. The reaction was label-free and monitored in real time with an oblique-incidence reflectivity-difference (OI-RD) technique. The kinetic constants k_on and k_off and the equilibrium dissociation constant K_d for this reaction were also obtained. These parameters indicate that the antibody is capable of detecting InlA. Additionally, the results also demonstrate the feasibility of using OI-RD for proteomics research and bacteria detection.