• Korean Chemical Engineering Research
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• 제44권1호
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• pp.52-57
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• 2006

에탄올과 함께 탄소, 질소원을 함유한 맥주 폐 발효액을 저렴한 대체배지로 사용하고 Gluconacetobacter hansenii PJK(KCTC 10505 BP) 균주를 이용하여 미생물셀룰로오스를 생산하였다. 맥주 폐 발효액은 기본배지보다도 탄소원과 질소원이 풍부하였으며 미량의 황과 4％ 이상의 에탄올을 함유하였다. 진탕배양에서 맥주 폐 발효액을 사용하여 생산된 셀룰로오스량은 기본배지를 사용하여 생산된 셀룰로오스량과 필적하였다. 교반배양에서는 셀룰로오스 생산균주($Cel^+$ 균주)가 셀룰로오스를 생산하지 못하는 균주($Cel^-$ 돌연변이주)로 전환되는 률은 낮았지만 셀룰로오스 생산량은 감소하였다.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.515-521
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• 1994

A bacterial strain, which showed the high protease activity at low temperature and the high tolerance for the surfactant, was isolated from soil and identified as Xanthomonas sp. YL-37. The optimal temperature, initial pH, and cultivation time for the production of the alkaline protease by Xanthomonas sp. YL-37 were 20$\circC , 11.0, and 84 hours, respectively. In the jar fermenter culture of Xanthomonas sp. YL-37, the alkaline protease activity was about 15,000 DU/ml/-broth after cultivating for 108 hours. The optimal pH and temperature for the protease activity were 70$\circC and 11.0, respectively. The protease was relatively stable at the pH range of 7.0~12.0 and at the temperatures below 50$\circC . The protease activity at 20$\circC was about the level of 40% of its activity at 70$\circC . The enzyme was suggested as a serine protease because the enzyme activity was inhibited by phenylmethane sulfonyl fluoride, a serine modifier.

• Journal of the Korean Wood Science and Technology
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• 제28권4호
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• pp.29-40
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• 2000

Highly purified Cerrena unicolor laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) caused the demethoxylation of milled wood lignin and several lignin related substances. The constitutive form of the enzyme produced extracellularly by C. unicolor fermenter culture was isolated and purified by ion-exchange chromatography on the DEAE-Toyopearl column and by affinity chromatography on a ConA-Sepharose and Syringyl-AH-Sepharose 4B columns. The enzyme was further immobilized on functionalized porous glass (CPG) and keratin coated CPG. The demethylating activity was monitored both by estimation of released methanol and by detection of the level of methoxyl groups (also in some water miscible solvents) after incubation of lignin materials with laccase preparations (free and immobilized). The effects of the incubation time and temperature on the demethoxylating activity of immobilized laccase preparations were also studied.

• KSBB Journal
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• 제18권6호
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• pp.473-478
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• 2003

본 연구의 목적은 메탄을 최대로 발생시킬 수 있는 최적조건을 탐색하는데 있다. 탐색한 최적조건 인자로는 온도, pH, 탄소원, 그리고 질소원이며, 메탄 발생에 영향을 주는 저해제에 대해서도 조사하였다. 결과적으로, 온도는 3$0^{\circ}C$, pH는 중성영역, 탄소원은 methanol, 질소원은 NH$_4$Cl에서 최대의 메탄을 얻을 수 있었으며, 메탄 생성에 대한 저해재의 영향을 조사한 결과 10 mM 미만의 극소량이라도 2-bromoethanesulfonic acid가 존재할 경우 메탄 발생량이 감소하는 결과를 보였다. 메탄 발생에 대한 pH 변화를 조사해 본 결과, pH가 7.5에서 6.5로 내려가는 동안에는 메탄 발생량이 증가하였으나, 6.5에서 6.0으로 변화되면서는 메탄 발생량이 감소하였다. 따라서 pH 변화를 실시간으로 측정하여 상분리 발효를 적용하면 최적 메탄 생성 조건을 유지할 수 있을 것으로 사료된다. 또한 메탄 발생 시 배지 내에 생성되는 유기산을 측정해 본 결과 생성된 유기산 중 formic acid가 0.1M로 최대량을 보였다.

• Journal of Microbiology
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• 제37권4호
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• pp.200-205
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• 1999

7-Aminocephalosporanic acid (7-ACA) is the initial compound in preparation of cephalosporin antibiotics widely used in clinical treatment. Bacteria producing glutaryl 7-ACA acylase, which convert cephalosporin C to 7-ACA, has been screened in soil samples. A bacterial strain exhibiting high glutaryl 7-ACA acylase activity, designated KAC-1, was isolated and identified as a strain of Pseudomonas diminuta by characterizing its morphological and physiological properties. The screening procedures include culturing on enrichment media containing glutaric acid, glutamate, and glutaryl 7-aminocephalosporanic acid as selective carbon sources. To enhance enzyme production, optimal cultivation conditions were investigated. This strain grew optimally at pH 7 to 9 and in temperatures of 20 to 40 C, but acylase production was higher when the strain was grown at 25 C. Glutaric acid, glutamate and glucos also acted as inducers for acylase production. In a jar fermenter culture, P. diminuta KAC-1 produce acylase in a growth-associated manner. The substrate specificity of KAC-1 acylase by cell extract showed that this enzyme had specificity toward glutaryl 7-ACA, glutaryl 7-ADCA, but not cephalosporin C.

• 생명과학회지
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• 제14권1호
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• pp.51-56
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• 2004

장수상황버섯(Phellinus baumii)의 균사체 성장 및 세포외 다당체(exopolysaccharides) 생산을 위한 액체배양의 최적 배지 및 배양조건에 관한 실험을 수행한 결과, 최적배양 온도와 초기 pH는 각각 3$0^{\circ}C$와 5.0으로 결정되었다. 탄소원의 경우, cellobiose와 maltose가 균사체 성장에는 양호하였으나 저조한 세포외 다당체 생산을 보였으며, 반면에 fructose 와 mannitol 은 상대적으로 높은 수율의 세포외 다당체 생산과 균사체 성장 또한 양호하였다. 최적 질소원으로는 yeast extract가 균사체 성장뿐만 아니라 세포외 다당체 생산에 효과적인 것으로 결정되었다. 최적 배지의 조성은 fructose 20 g/L, yeast extract 20 g/L 및 $CaCl_2$ 0.55 g/L이었으며, 최적 배양조건 하에서 5-L 교반 발효조를 운전한 결과, 최대 균사체 성장(17.43 g/L)과 최대 세포외 다당체 생산(3.6 g/L)을 얻을 수 있었다. 회수된 세포외 다당체는 glycoprotein이었으며 그 조성은 amino acid분석 결과 주로 arginine (14.1%)과 glycin (12.0%)이었으며, cabohydrate의 경우는 mannose (48.7%)와 arabinose (38.4%)이 주성분이었다.

• Journal of Applied Biological Chemistry
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• 제53권3호
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• pp.179-183
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• 2010

각종 버섯에서 항보체 활성균주를 선별하기 위해 보관균주 50여종과 임업협동조합에서 분양 받은 20여종의 균주를 대상으로 항보체 활성을 검색한 결과, 항보체 활성이 65.3%를 나타낸 상황버섯 (Phellinus linteus)을 선별하였다. 본 균주가 생산하는 항보체 활성의 본체를 파악하기 위해 pronase 처리와 periodate 산화를 행한 결과 pronase로 처리한 사료는 무처리군과 비교하여 차이가 없었던 반면 periodate로 산화시킨 시료는 항보체 활성이 크게 감소함에 따라 P. linteus가 생산하는 항보체 활성의 본체는 다당에 기인되는 것으로 추정되었다. 항보체 생산을 위한 최적 배양조건은 soluble starch 3.0%, peptone 0.3%, yeast extract 0.4%, $MgSO_4{\cdot}7H_2O$ 0.1%, $K_2HPO_4$ 0.2%, 초기 pH 7.0, 배양 온도 $30^{\circ}C$ 및 교반속도 150rpm이었다. 상기의 최적 배양조건에서 jar fermentor로 18일 배양하였을 때 88%의 항보체 활성과 15mg/mL의 균사체 생육을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.234-239
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• 2012

The objective of this study was to evaluate the effects of forage level and oil supplement on selected strains of rumen bacteria believed to be involved in biohydrogenation (BH). A continuous culture system consisting of four fermenters was used in a $4{\times}4$ Latin square design with a factorial arrangement of treatments, with four 10 d consecutive periods. Treatment diets were: i) high forage diet (70:30 forage to concentrate (dry matter basis); HFC), ii) high forage plus oil supplement (HFO), iii) low forage diet (30:70 forage to concentrate; LFC), and iv) low forage plus oil supplement (LFO). The oil supplement was a blend of fish oil and soybean oil added at 1 and 2 g/100 g dry matter, respectively. Treatment diets were fed for 10 days and samples were collected from each fermenter on the last day of each period 3 h post morning feeding. The concentrations of vaccenic acid (t11C18:1; VA) and c9t11 conjugated linoleic acid (CLA) were greater with the high forage diet while the concentrations of t10 C18:1 and t10c12 CLA were greater with the low forage diet and addition of oil supplement increased their concentrations at both forage levels. The DNA abundance of Anaerovibrio lipolytica, and Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) were lower with the low forage diets but not affected by oil supplement. The DNA abundance of Butyrivibrio fibrisolvens stearic acid producer subgroup (Butyrivibrio SA) was not affected by forage level or oil supplement. In conclusion, oil supplement had no effects on the tested rumen bacteria and forage level affected Anaerovibrio lipolytica and Butyrivibrio VA.

• KSBB Journal
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• 제8권2호
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• pp.150-155
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• 1993

난분해성인 색소를 대사분해할 수 있는 미생물을 분리하여, 색소분해의 최적조건을 조사하였다. 미생물은 폐수처리공장의 폭기조에서 채취한 폐수로부터 agar media에서 순수분리하였다. 이 균주들을 glu­c cose, peptone, $Na_2HPO_45, KCI, MgSO_4, KH_2PO_4, NaCI, CaCI_2$와 dye(azo계, reactive red계 ) lOppm 을 함유한 액체 배지에서 dye의 분해력이 강하였으 며, 이때의 최적 pH는 중성 또는 약알칼리성이고, 최적 온도는 $30^{\circ}C$ 전후이다. 이 조건에서 10ppm의 m mono-azo(Lot No. 180), di-azo(Lot No. 138), re­a active red(Lot No.2)는 약 2일에 거의 분해되었고, di-azo(Lot No. 151), reactive red(Lot No. 34, L Lot No. 00166)는 약 5일에 거의 분해되었고, 최적 배지조건하에서 산소의 영향은 D.O를 50%로 유지 시켰을 경우보다 혐기성 배양의 경우가 reactive d dye(Lot No.2)의 분해도가 훨씬 높았다.

• 한국식생활문화학회지
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• 제14권5호
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• pp.461-466
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• 1999

As a part of investigation to use sardine(Sardinops melanoslicta) more effectively as a food source, this study was undertaken the processing condition of rapid- and low salt-fermented liquefaction of sardine. To prepare rapid fermented products, the chopped whole sardine was added 8% NaCl and then preheating treatment at $40^{\circ}C,\;45^{\circ}C$ and $50^{\circ}C$ in the manufactured fermenter(180L) for 9 hrs, and then fermentation at $33^{\circ}C$ for 90 days. The chemical changes such as amino nitrogen(amino-N), volatile basic nitrogen(VBN), and histamine in the hydrolysates of fermented sardine were analyzed as well as viable cell count and organoleptic evaluation during fermentation to compare the quality between control and preheating samples. During fermenting, the amino-N in the hydrolysates increased rapidly during the first 30 days and slowly thereafter. The highest content of amino-N appeared at 75 days in control sample and $60{\sim}75$ days in preheating samples. The changes of VBN in the hydrolysates increased rapidly during first 15 days in control samples and 30 days in preheating samples. However they were generally low level in preheating samples. Histamine content in the hydrolysates of the control samples increased markedly after 15 days, but preheating samples were generally low level, and then $75{\sim}90$ days of fermentation reached to the maximum which was about $2.0{\sim}3.0$ times lower than that of control samples. As for the organoleptic flavor evaluation, the control and preheating at $40^{\circ}C$ samples were unpleasant odor after 15 and 60 days, respectively. But preheating at $45^{\circ}\;and\;50^{\circ}$ samples were fresh odor after 90 days fermentation.