• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.538-544
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• 1998

One hundred and twenty-eight finishing pigs (51.3 kg average initial body weight) were used to determine the effects of adding cellulase enzymes and lactobacillus acidophilus to sorghum-based diets on growth performance, carcass merit, and nutrient digestibility in finishing pigs. Treatments were: 1) corn-soybean meal-based positive control; 2) sorghum-soybean meal-based negative control; 3) Diet 2 with celluloytic enzymes; and 4) Diet 2 with a bacterial feed additive (lactobacillus acidophilus). There was a trend for greater average daily gain (ADG) in pigs fed com versus the sorghum treatments for day 0 to 28 (p < .09), but there was no effect of treatment (p > .15) on overall ADG (i.e., day 0 to 63). Feed consumption was not affected by treatment during the experiment (p > .19). Pigs fed the corn-soybean meal-based diet had 3.5% greater overall gain/feed than pigs fed the other diets (p < .009). Dressing percentage was not affected by treatment (p > .22), but there was a trend for backfat thickness at the last rib to be greater for pigs fed com versus the sorghum treatments (p < .09). Pigs fed the sorghum treatments had 1 % greater fat free lean index (p < .10) compared to pigs fed the corn-soybean meal-based positive control. Pigs fed com had greater apparent digestibilities of DM, N, and GE than pigs fed the sorghum treatments (p < .03), and greater DE intake (p < .07) suggesting that the increased carcass fatness for pigs fed the corn-based control diet resulted from greater energy status of those pigs. In conclusion, pigs fed the corn-soybean meal-based control diet had no improved growth performance but tended to be fatter than pigs fed sorghum. Adding cellulolytic enzymes or a bacterial feed additive to diets for finishing pigs did not affect growth performance, carcass merit, or nutrient utilization.

• Journal of Microbiology
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• 제43권spc1호
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• pp.101-109
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• 2005

To gain maximal benefit in a competitive environment, single-celled bacteria have adopted a community genetic regulatory mechanism, known as quorum sensing (QS). Many bacteria use QS signaling systems to synchronize target gene expression and coordinate biological activities among a local population. N-acylhomoserine lactones (AHLs) are one family of the well-characterized QS signals in Gram-negative bacteria, which regulate a range of important biological functions, including virulence and biofilm formation. Several groups of AHL-degradation enzymes have recently been identified in a range of living organisms, including bacteria and eukaryotes. Expression of these enzymes in AHL-dependent pathogens and transgenic plants efficiently quenches the microbial QS signaling and blocks pathogenic infections. Discovery of these novel quorum quenching enzymes has not only provided a promising means to control bacterial infections, but also presents new challenges to investigate their roles in host organisms and their potential impacts on ecosystems.

• 환경생물
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• 제17권1호
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• pp.59-69
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• 1999

동해 연안역의 부영양화 상태 및 종속영양세균에 의한 유기물질 분해능을 조사하기 위해서 대진, 갈남, 포항, 울산의 4개 지역의 연안역을 대상으로 1994년 7월부터 1995년 4월까지 4회에 걸쳐 종속영양세균군집, 오염의 신호화합물, 세균의 생산력, 종속영양활성도 및 세포외 효소활성도 등을 분석하였다. 중금속내성균의 수는 포항에서 가장 높게 나타났으며, 각종 유기인을 이용하는 세균군집을 조사한 결과 유기인(C-P)화합물이 많이 포함될 것으로 예상되는 산업폐수, 가정하수 및 농업폐수 등이 많이 유입되는 정점에서 이들 유기인 화합물을 분해하고 산화 환원시키는 세균군집이 높게 나타났다. 이들 세균의 출현빈도는 산업폐수, 가정하수 그리고 농업용수의 유입예측지표로 활용될 수 있으리라 생각된다. 세포외 효소활성도는 울산 처용암에서 가장 높았으며 대진에서 가장 낮게 나타났다. 이러한 결과는 종속영양 세균수와 세균의 생산성 등과 정의 상관관계를 나타내었다. Poly-P와 DNA의 경우, 정점별로는 포항이 가장 높았고, 울산, 갈남, 대진 순으로 나타났다. 이는 종속영양세균의 분포양상과 매우 일치하는 것으로 조사되었다. 종속영양 활성도는 정점별, 계절별 변화가 매우 심하였다. 세균의 생산력은 하계에 가장 높고 추계와 동계에 낮았다가 춘계에 다시 높아지는 경향을 나타나 종속영양세균의 계절적 변화양상과 유사한 경향을 보였다. 결과적으로 세균의 군집, poly-P함량, 세균의 생산력, 종속영양활성도 및 세포외 효소활성도 등의 분석자료는 부영양화 상태 및 유기물질의 순환과정을 파악할 수 있는 지표로 이용될 수 있다.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.678-682
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• 2006

To remove nitrate from wastewater, a novel bioelectrochemical denitrification system is introduced. In this proposed system, biological reactions are coupled with reactions on the electrode, whereby the electrons are transferred to the bacterial enzymes via a mediator as an electron carrier. The denitrification reaction was achieved with permeabilized Ochrobactrum anthropi SY509 containing denitrifying enzymes, such as nitrate reductase, nitrite reductase, and nitrous oxide reductase, and methyl viologen was used as the mediator. The electron transfer from the electrode to the enzymes in the bacterial cells was confirmed using cyclic voltammetry. A high removal efficiency of nitrate was achieved when the bioelectrochemical system was used with the permeabilized cells. Furthermore, when the permeabilized cells were immobilized to a graphite felt electrode using a calcium alginate matrix containing graphite powder, a high removal efficiency was achieved (4.38 nmol/min mg cell) that was comparable to the result when using the free permeabilized cells.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1907-1915
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• 2017

Lipases are important enzymes with biotechnological applications in dairy, detergent, food, fine chemicals, and pharmaceutical industries. Specifically, hormone-sensitive lipase (HSL) is an intracellular lipase that can be stimulated by several hormones, such as catecholamine, glucagon, and adrenocorticotropic hormone. Bacterial hormone-sensitive lipases (bHSLs), which are homologous to the C-terminal domain of HSL, have ${\alpha}/{\beta}-hydrolase$ fold with a catalytic triad composed of His, Asp, and Ser. These bHSLs could be used for a wide variety of industrial applications because of their high activity, broad substrate specificity, and remarkable stability. In this review, the relationships among HSLs, the microbiological origins, the crystal structures, and the biotechnological properties of bHSLs are summarized.

• Archives of Pharmacal Research
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• 제25권6호
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• pp.964-968
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• 2002

Colon drug delivery is advantageous in the treatment of colonic disease and oral delivery of drugs unstable or suceptible to enzymatic degradation in upper GI tract. In this study, multilayer coated system that is resistant to gastric and small intestinal conditions but can be easily degraded by colonic bacterial enzymes was designed to achieve effective colon delivery of prednisolone. Variously coated tablets containing prednisolone were fabricated using chitosan and cellulose acetate phthalate (CAP) as coating materials. Release aspects of prednisolone in simulated gastrointestinal fluid and rat colonic extracts (CERM) were investigated. Also, colonic bacterial degradation study of chitosan was performed in CERM. From these results, a three layer (CAP/Chitosan/CAP) coated system exhibited gastric and small intestinal resistance to the release of prednisolone in vitro most effectively. The rapid increase of prednisolone in CERM was revealed as due to the degradation of the chitosan membrane by bacterial enzymes. The designed system could be used potentially used as a carrier for colon delivery of prednisolone by regulating drug release in stomach and the small intestine.

• IMMUNE NETWORK
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• 제14권1호
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• pp.7-13
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• 2014

Molecular mimicry is an attractive mechanism for triggering autoimmunity. In this review, we explore the potential role of evolutionary conserved bacterial proteins in the production of autoantibodies with focus on granulomatosis with polyangiitis (GPA) and rheumatoid arthritis (RA). Seven autoantigens characterized in GPA and RA were BLASTed against a bacterial protein database. Of the seven autoantigens, proteinase 3, type II collagen, binding immunoglobulin protein, glucose-6-phosphate isomerase, ${\alpha}$-enolase, and heterogeneous nuclear ribonuclear protein have well-conserved bacterial orthologs. Importantly, those bacterial orthologs are also found in human-associated bacteria. The wide distribution of the highly conserved stress proteins or enzymes among the members of the normal flora and common infectious microorganisms raises a new question on how cross-reactive autoantibodies are not produced during the immune response to these bacteria in most healthy people. Understanding the mechanisms that deselect auto-reactive B cell clones during the germinal center reaction to homologous foreign antigens may provide a novel strategy to treat autoimmune diseases.

• 미생물학회지
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• 제19권3호
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• pp.137-141
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• 1981

Occurrence and distribution of sucrose metabolizing enzymes in oral streptococci had been studied. In these studies, the carbohydrate component of the culture medium had been glucose. I have extended these studies by analyzing bacterial culture supernatants for the relative content of hexosyltransferases, namely glucosyl and fructosyltransferase. As a carbohydrate, fructose was used. The growth measured for nine oral streptococci (Strptococcus mutans strains BHT, ING, AHT, 6715, LM-7, and SL-1 ; Streptococcus sanguis 903, 9811, and M-5) varied. The level of glucosyltansferase activity also varied among S. mutans strains, and its level in S. sanguis was relatively low. Fructosyltansferase activity of the various strains fluctuated more than of glucosyltransferase. S.mutans strain LM-7 had significantly higher level of both enzymes. As a whole, fructose-grown cultures had generally an agreeable trend of enzyme activity to those from glucose-grown cultures.

• 한국식품영양과학회지
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• 제27권2호
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• pp.244-251
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• 1998

To understand the effect of supplement of water extract of pine needle(WEPN) on shelf-life enhancement of the kimchi, activities of four enzymes and number of lactic acid bacteria, during fermentation of the kimchi, were assayed. Enzyme activities of kimchi fermented for 7 days with supplement by 2% water extract of pine needle showed amylase of 86.4%, protease of 85.8%, polygalacturonase of 61.5% and $\beta$-galactosidase of 58.8% against the control kimchi. WEPN showed weak inhibitory effect when it was applied to the isolated enzymes in vitro then those menifested by the kimchi in vivo. Number of total bacterial cell of WEPN supplemented kimchi increased by 10 folds than control between 7 to 14 days of fermentation. On contrast, number of lactic acid bacteria decreased maximaly to 21% of control by fermentation. The clear zone formed on paper disk by WEPN against L. plantarum was larger than that of Leu. mesenteroides.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.19-19
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• 2014

Pleurotus ostreatus, P. eryngii, and Flammulina velutipes are major edible mushrooms that account for over 89% of total mushroom production in Korea. Recently, Agrocybe cylindracea, Hypsizygus marmoreus, and Hericium erinaceu are increasingly being cultivated in mushroom farms. In Korea, the production of edible mushrooms was estimated to be 614,224 ton in 2013. Generally, about 5 kg of mushroom substrate is needed to produce 1 kg of mushroom, and consequently about 25 million tons of spent mushroom substrate (SMS) is produced each year in Korea. Because this massive amount of SMC is unsuitable for reuse in mushroom production, it is either used as garden fertilizer or deposited in landfills, which pollutes the environment. It is reasonably assumed that SMS includes different secondary metabolites and extracellular enzymes produced from mycelia on substrate. Three major groups of enzymes such as cellulases, xylanases, and lignin degrading enzymes are involved in breaking down mushroom substrates. Cellulase and xylanase have been used as the industrial enzymes involving the saccharification of biomass to produce biofuel. In addition, lignin degrading enzymes such as laccases have been used to decolorize the industrial synthetic dyes and remove environmental pollutions such as phenolic compounds. Basidiomycetes produce a large number of biologically active compounds that show antibacterial, antifungal, antiviral, cytotoxic or hallucinogenic activities. However, most previous researches have focused on therapeutics and less on the control of plant diseases. SMS can be considered as an easily available source of active compounds to protect plants from fungal and bacterial infections, helping alleviate the waste disposal problem in the mushroom industry and creating an environmentally friendly method to reduce plant pathogens. We describe extraction of lignocellulytic enzymes and antimicrobial substance from SMSs of different edible mushrooms and their potential applications.