• 청정기술
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• 제8권4호
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• pp.199-203
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• 2002

석유탄화수소의 분해능이 확인된 Pseudomonas fluorescens KCTC 1767을 이용하여 혐기 상태에서 톨루엔 분해의 최적조건을 찾기 위해서 회분식으로 pH, 회전속도, 온도를 변수로 하여 실험하였고, 토양 생물반응기에서는 연속식으로 톨루엔을 분해하는 최적의 순환유속을 찾고자 실험하였다. 온도 $15^{\circ}C$, 초기 pH 7의 회분식 실험에서 rpm에 따른 톨루엔 분해는 45시간이 경과한 후에 120rpm의 경우 잔여농도 37.4 ppm으로 62.6%의 분해율, 180 rpm의 경우 잔여농도 13.0 ppm으로 83% 분해율, 60 rpm의 경우는 불검출로 60 rpm에서 가장 좋은 결과를 보였으며, 회전속도 120rpm, 초기 pH 7에서 실시한 회분식 실험에서 톨루엔 분해는 45시간 경과후 $15^{\circ}C$에서는 잔여농도 37.4 ppm을 보였으나 $30^{\circ}C$에서는 검출이 되지 않아 대부분의 분해된 것으로 나타났다. 온도 $30^{\circ}C$, 초기 pH 7의 조건에서 탱크 내 균체량은 35 mL/min에서 0.19g/L 를 보여 최고의 성장을 보였으며, 톨루엔은 9시간이후 검출되지 않았다. 혐기상태에서 Pseudomonas fluorescens KCTC 1767를 이용하여 톨루엔을 분해하는데 회분식실험과 연속식 토양생물반응기에서의 최적조건은, 회분식의 경우 60 rpm과 온도 $30^{\circ}C$인 것으로 나타났으며, 연속식 토양 생물반응기의 경우 55mL/min, 80mL/min, 85 mL/min중 가장 낮은 유속인 55 mL/min 에서 결과가 좋았다.

• 한국식생활문화학회지
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• 제27권6호
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• pp.743-750
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• 2012

A tissue cultured wild ginseng (TCWG) suspension was inoculated with lactic acid bacteria and fermented to improve the functionality of TCWG. The utilization of TCWG was increased directly using the freeze-dried powder. The optimal ratio of TCWG powder and water for fermentation was 1:19 (5%), which was selected by measuring the fluidity and viable cell count according to concentration. The effects on ADH activation and immune cell activation by each ferments with 10 kinds of Lactobacillus sp. strains were examined. The ferments with the Lactobacillus casei KFRI 692 strain showed 5.4 times higher ADH activity and 1.3 times higher ALDH activity than the non-fermented TCWG powder (control). The level of NO production and cytotoxicity was also measured by Raw 264.7 cells. The ferment with the Lac. casei KFRI 692 strain showed the highest level of NO production and lower cytotoxicity than the others. Therefore, the Lac. casei KFRI 692 strain was selected as a strain for fermentation of a TCWG suspension to maximize its functionality. To identify the optimal fermentation time of the selected Lac. casei KFRI 692 strain on the 5% TCWG suspension, the viable cell count of lactic acid bacterial and the changes in pH were observed for 72 hours. 24-hrs was found to be the optimal fermentation time. In this way, fermented TCWG with lactic acid bacteria showed higher ADH activation efficacy and immune cell activation than non-fermented TCWG.

• 한국식품영양학회지
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• 제25권4호
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• pp.1055-1060
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• 2012

In order to produce Hongkuk-ju, the production and characterization of Hongkuk (Monascus red koji) by Monascus anka KCTC 6121 were investigated. The optimum cultural conditions for the production of enzyme (${\alpha}$-amylase and glucoamylase) and pigment (yellow and red) from this strain on solid culture (steamed rice) were examined. The results showed that the production of ${\alpha}$-amylase and glucoamylase reached the highest for 9 days and 8 days, respectively. Since then, the productions decreased slightly. The production of yellow and red pigments reached the highest for 8 days, decreasing slightly soon after. The optimal content of the initial moisture equally presented 30% in the enzyme and pigment production. After that, the enzyme production decreased slowly, whereas pigment production decreased sharply. The optimal temperature of the culture also showed $30^{\circ}C$ in the production of enzyme and pigment. It was found that the initial inoculum size in enzyme and pigment production was 10% and 20%, respectively. Under these optimal conditions, the production of monacolin K and citrinin was 74.35 mg/kg and 5 mg/kg for 12 days, respectively.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.1054-1057
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• 2007

Lipases are industrially useful versatile enzymes that catalyze numerous different reactions including hydrolysis of triglycerides, transesterification, and chiral synthesis of esters under natural conditions. Although lipases from various sources have been widely used in industrial applications, such as in food, chemical, pharmaceutical, and detergent industries, there are still substantial current interests in developing new microbial lipases, specifically those functioning in abnormal conditions. We screened 17 lipase-producing yeast strains, which were prescreened for substrate specificity of lipase from more than 500 yeast strains from the Agricultural Research Service Culture Collection (Peoria, IL, U.S.A.), and selected Yarrowia lipolytica NRRL Y-2178 as a best lipase producer. This report presents new finding and optimal production of a novel extracellular alkaline lipase from Y. lipolytica NRRL Y-2178. Optimal culture conditions for lipase production by Y. lipolytica NRRL Y-2178 were 72 h incubation time, $27.5^{\circ}C$, pH 9.0. Glycerol and glucose were efficiently used as the most efficient carbon sources, and a combination of yeast extract and peptone was a good nitrogen source for lipase production by Y. lipolytica NRRL Y-2178. These results suggested that Y. lipolytica NRRL Y-2178 shows good industrial potential as a new alkaline lipase producer.

• 한국미생물·생명공학회지
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• 제37권3호
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• pp.219-225
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• 2009

본 연구는 해양유래의 특이색소미생물을 선발하여 미생물의 특성 및 이차대사산물의 생리활성 탐색을 통해 새로운 생물자원개발을 위해 수행되었다. 본 연구에 사용된 prodigiosin 유사 색소를 생산하는 균주 JE-34는 동중국해 퇴적층으로부터 분리되었으며 Zooshikella sp. JE-34으로 명명하였다. Zooshikella sp. JE-34는 적색색소를 다량 생산하였으며 대표적인 prodigiosin 생산균주인 Serratia marcscens의 색소추출액과 분광학적 특성 및 HPLC 분석을 통해 JE-34가 생산하는 색소가 prodigiosin 유사색소로 판단되었다. JE-34 균주의 배지조성에 따른 생육도 및 pigment 생합성의 변화를 알아보기 위해 탄소원, 질소원, 무기염류를 첨가하며 배양한 결과 탄소원으로는 soluble starch, 질 소원으로는 malt extract, 무기염류로는 $Na_2HPO_4$에서 최적의 pigment를 생산하였다. Zooshikella sp. JE-34는 prodigiosin의 생합성에 있어 대표적인 생산자인 Serratia marcscens와 마찬가지로 우수한 pigment 생합성량을 보여 prodigiosin의 생합성의 생물자원으로서 의의가 있다고 사료된다.

• 한국식생활문화학회지
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• 제34권6호
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• pp.779-784
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• 2019

The purpose of this study was to optimize the rice protein extracted using a response surface methodology. The experiment was designed based on a CCD (Central Composite Design), and the independent variables were the high pressure (X₁, 0-400 MPa) and processing time (X₂, 0-10 minutes). The results of the extraction content (Y₁), residue content (Y₂), and recovery yield (Y₃) were fitted to a response surface methodology model (R²= 0.92, 0.92, and 0.93, respectively). Increasing the pressure and processing time has a positive effect on the extraction content (Y₁), residue content (Y₂), and recovery yield (Y₃). Therefore, these high-pressure conditions (independent variables) can significantly affect the improvement in rice protein extraction efficiency. Thus, the optimal conditions of X₁ and X₂ were 400 MPa and 10 min., respectively. Under these optimal conditions, the predicted values of Y₁, Y₂, and Y₃ were 62.93, 57.53 mg/g, and 91.76%, respectively.

• 한국인터넷방송통신학회논문지
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• 제17권2호
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• pp.135-140
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• 2017

세계 수산시장은 초과 수요적 현상으로 이러한 경향은 지속적으로 가속화 될 것으로 전망하고 있다. 수산물 수요가 증가되는 양식업은 어업과 비교해 볼 때 비교적 적은 자원의 투입으로도 생산량의 조절 및 표준화 등이 가능하여 높은 성과를 얻을 수 있는 산업이다. 그러나 전통적인 양식은 자연재해, 생태계 오염 등 저생산성의 문제점을 안고 있어 최적의 양식장소로 이동할 수 있는 새로운 양식시스템의 개발이 필요하다. 최적의 장소를 찾기 위해서는 온도, 산소 용존량 등 필요한 데이터를 실시간으로 수집하고 분석해야 한다. 데이터 분석은 머신러닝 기반의 K-means 클러스터링 기법을 적용하여 반복된 자기학습으로 언제, 어디로 양식장을 이동할지 스스로 판단할 수 있도록 하였다. 제시한 연구결과가 어류 양식업 종사자에게 적용된다면 최적의 양식장소를 스스로 찾아감으로써 자연재해, 생태계 오염 등 저생산성의 문제점을 해결 할 수 있을 것이다.

• 한국임상수의학회지
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• 제36권5호
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• pp.253-258
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• 2019

The objective of this study was to analyse the effects of MS-275 (Class I and II histone deacetylase inhibitor) supplementation on the development of porcine in-vitro somatic nuclear transfer embryo production. During in-vitro development, early embryos were exposed to different concentrations of MS-275 (0, $5{\mu}M$, $10{\mu}M$, and $20{\mu}M$). In in-vitro culture supplemented group, the blastocyst development rate was significantly enhanced by $10{\mu}M$ concentration than other groups (24.0% vs. 19.3%, 21.8%, 11.5%; P < 0.05). Additionally, the 6 h supplementation group, significantly improved the blastocysts production than 24 h, 48 h and control groups (26.1% vs. 17.0%, 15.2%, 2.8%; P < 0.05). Following supplementation with optimal concentrations and time ($10{\mu}M$-6 h group), the blastocyst production was significantly higher than control (25.7% vs 15.8%; P < 0.05). The optimal concentrations of MS-275 significantly enhanced the percentages of ICM:TE than control (43.6% vs. 38.4%; P < 0.05) accompanied with significantly higher expression levels of reprogramming related genes (POU5F1, Naong, and SOX2). In conclusion, the optimal concentrations of $10{\mu}M$ MS-275 and 6 h supplementation during in-vitro culture can significantly improve the quality of porcine in-vitro somatic nuclear transfer embryos through histone acetylation and epigenetic modification. Increasing the efficiency of clonal animal production will greatly promote the development of animal disease models and xenotransplantation.

• 한국식생활문화학회지
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• 제34권5호
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• pp.637-644
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• 2019

The purpose of this study was to optimize the mandarin dry chip manufacturing using a response surface methodology. The experiment was designed based on a CCD (Central Composite Design), and the independent variables were the drying temperature ($X_1$, $50-90^{\circ}C$), drying time ($X_2$, 12-36 hours), and microwave pretreat time ($X_3$, 0-4 minutes). The results of appearance ($Y_5$), color ($Y_6$), taste ($Y_8$) and overall acceptance ($Y_{10}$) were fitted to the response surface methodology model ($R^2=0.86$, 0.88, 0.89, and 0.84, respectively). Increasing the drying temperature and microwave treatment time were negatively evaluated for consumer acceptance. On the other hand, a high value of consumer acceptance was evaluated when the drying time was more than 24 hr. Therefore, the optimal conditions of $X_1$, $X_2$, and $X_3$ were $52.989^{\circ}C$, 24 hr, and 1 min, respectively. Under these optimal conditions, the predicted values of $Y_5$, $Y_6$, $Y_8$, and $Y_{10}$ were 5.066, 5.338, 5.063, and 5.339, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• 제35권2호
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• pp.111-117
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• 2017

Mulberry leaves containing 1-deoxynojirimycin (DNJ) known to be a strong inhibitory effect for ${\alpha}-glucosidase$. Thus, DNJ has been recognized as a potentially important source for prevent or treat hyperglycemia. More effective method for the DNJ high-production is needed because DNJ content of natural mulberry leaf are as low as 0.1%. Many researchers have studied for the DNJ high-production in mulberry leaves such as the harvest season, fermentation using microorganisms, optimal culture conditions, and optimal extraction conditions. In order to provide for useful data that is anticipated at the level of industrial scale, we investigated ${\alpha}-glucosidase$ inhibitory activity, pH value and DNJ content in large-scale based on the optimal culture conditions for mulberry leaf fermentation of small-scale in our previous study. The ${\alpha}-glucosidase$ inhibitory activity, pH value, and DNJ content in this study were measured from the mulberry leaf fermentation broth for 7 days. During mulberry leaf fermentation, the ${\alpha}-glucosidase$ inhibitory activity and DNJ content was increased until 2 to 4 days, but after 4 day was decreased. The pH value showed a decreasing trend up to 2 day, and little changes in 2 to 4 days. However, the pH was started to increase after 4 days.