• 한국식품영양과학회지
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• 제25권4호
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• pp.608-616
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• 1996

참치 가공 부산물로 부터 유용한 식량소재를 찾기위한 목적으로 상업용 단백질 분해효소를 이용하여 반응표면분석법에 의한 최적화한 조건에서 참치 가수 분해물을 제조한 결과를 요약하면 다음과 같다. 8종의 상업용 단백질 분해효소에서 가격에 대한 효소활성도와 관능검사 결과치로부터 Pretease P가 최적 효소로 선정되었으며, 참치 가공 부산물 가수분해 과정중 원료 자체의 가수분해효과는 없었다. 반응표면분석 결과 결정계수(0.9460) 및 적합결여검증(P>0.1)을 통해, 본 실험의 디자인이 만족하게 설계되었음을 알 수 있었고 일차식 및 이차식에서는 p<0.05% 수준에서 유의하였다. 다중회귀분석 및 능선분석 결과, 가수분해물 제조를 위한 최적 조건은 pH 7.2, 반응온도 $51^{\circ}C,$ 기질농도 33.3%, 기질에 대한 효소농도 0.48%에서 3.94시간 가수분해시 킬 때이며, 이때의 가수분해율은 64.88%였다.

• 한국식생활문화학회지
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• 제16권2호
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• pp.170-179
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• 2001

Green Tea consists of 15-30% catechins (a type of polyphenol), which act as super antioxidants, inhibitory action against aging process. Antioxidants fight radical-free oxygen, an agent which can begin the process of cancer by damaging essential body chemicals and harming DNA. This study was peformed to develop the elderly diet using Green Tea as an inhibitory action against aging process. Nokchaborijook (Baley gruel added rice powder and Green Tea) was manufactured by various levels of Green Tea(1, 4, 7%) and the grinding period(15, 30, 45 sec). The optimum levels of added Green Tea and grinding periods on Nokchaborijook were determined with the results of sensory evaluation by response surface methodology and analysis of composition. The Anti-oxidant Vitamin A, C, E and Flavonoid were increased with increased levels of Green Tea and grinding periods be decreased. As the levels of Green Tea and grinding periods were increased, the green color and penetrated force became stronger. Among the sensory attributes, Bitterness, Green Tea Flavor and Hashness were greater depending on increasing Green Tea. Jujube flavor was greater relying on decreasing Green Tea. Greenness and spreadability of particles were increased as both the amounts of Green Tea and the grinding period were increased. This result was used to determine the optimum conditions of adding levels of Green Tea and grinding periods. The optimum conditions of Nokchaborijook was established as adding of 5.8% Green Tea grinded for 15 seconds.

• 한국미생물·생명공학회지
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• 제44권1호
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• pp.48-54
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• 2016

본 연구에서는 홍조류 중 하나인 E. cottonii로부터 환원당을 생산하기 위하여 산 가수분해법을 수행하였다. 반응표면분석법을 이용한 반응조건의 최적화를 통하여 환원당 생성에 미치는 반응인자들의 상호작용을 조사한 결과, 낮은 반응온도, 낮은 촉매농도, 그리고 짧은 반응시간의 조건에서 많은 양의 환원당이 생성되었고, 반면에 가혹한 반응조건일수록 당의 과분해산물인 5-HMF와 레불린산의 생성이 증가하였다. 환원당 생성의 최적 반응조건은 $160.1^{\circ}C$, 1.0% 황산, 그리고 13.1분의 반응시간 조건에서 25.8 g/l의 환원당 생성을 예측하였다. 이러한 결과로부터 해조류로부터 바이오연료 및 화학원료로 전환가능한 당의 확보 가능성을 제시하였고, 이상과 같이 얻어진 정보들은 향후 화석 자원을 대체하기 위한 기본 정보로 활용될 수 있다는 점에서 의의가 있다고 하겠다.

• Advances in environmental research
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• 제9권1호
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• pp.65-84
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• 2020

The potential use of Sargassum boveanum algae for the removal of uranium from aqueous solution has been studied by varying three independent parameters (pH, initial uranium ion concentration, S. boveanum dosage) using a central composite design (CCD) under response surface methodology (RSM). Batch mode experiments were performed in 20 experimental runs to determine the maximum metal adsorption capacity. In CCD design, the quantitative relationship between different levels of these parameters and heavy metal uptake (q) were used to work out the optimized levels of these parameters. The analysis of variance (ANOVA) of the proposed quadratic model revealed that this model was highly significant (R² = 0.9940). The best set required 2.81 as initial pH(on the base of design of experiments method), 1.01 g/L S. boveanum and 418.92 mg/L uranium ion concentration within 180 min of contact time to show an optimum uranium uptake of 255 mg/g biomass. The biosorption process was also evaluated by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models represented that the experimental data fitted to the Langmuir isotherm model of a suitable degree and showed the maximum uptake capacity of 500 mg/g. FTIR and scanning electron microscopy were used to characterize the biosorbent and implied that the functional groups (carboxyl, sulfate, carbonyl and amine) were responsible for the biosorption of uranium from aqueous solution. In conclusion, the present study showed that S. boveanum could be a promising biosorbent for the removal of uranium pollutants from aqueous solutions.

• KSBB Journal
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• 제29권3호
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• pp.131-138
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• 2014

In this study, we isolated two novel chitinase producing bacterial strains from yellow loess samples collected from Jullanamdo province. The chitinase producing bacteria were isolated based on the zone size of clearance in the chitin agar plates. Both of them were gram positive, rod ($2{\sim}3{\times}0.3{\sim}0.4{\mu}m$), spore-forming, and motility positive. They were facultative anaerobic, catalase positive and hydrolyzed starch, gelatin, and casein. From the 16s rRNA gene sequence analysis, the isolates were labeled as Bacillus licheniformis KYLS-CU01 and B. licheniformis KYLS-CU02. The isolates showed higher extracellular chitinase activities than B. licheniformis ATCC 14580 as a control. The optimum temperature and pH for chitinase production were $40^{\circ}C$ and pH 7.0, respectively. Response Surface Methodology (RSM) was used to optimize the culture medium for efficient production of the chitinase. Under this optimal condition, 1.5 times higher chitinase activity of B. licheniformis KYLS-CU02 was obtained. Extracellular chitinases of the two isolates were purified through ammonium sulfate precipitation and anion-exchange DEAE-cellulose column chromatography. The specific activities of purified chitinase from B. licheniformis KYLS-CU01 and B. licheniformis KYLS-CU02 were 7.65 and 5.21 U/mg protein, respectively. The molecular weights of the two purified chitinases were 59 kDa. Further, the purified chitinase of B. licheniformis KYLS-CU01 showed high antifungal activity against Fusarium sp.. In conclusion, these two bacterial isolates can be used as a biopesticide to control pathogenic fungi.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 제5회 박판성형 SYMPOSIUM
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• pp.55-60
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• 2006

Draw-bead is applied to control the material flow in a stamping process and improve the product quality by controlling the draw-bead restraining force (DBRF). Actual die design depends mostly on the trial-and-error method without calculating the optimum DBRF. Die design with the predicted value of DBRF can be utilized at the tryout stage effectively reducing the cost of the product development. For the prediction of DBRF, a simulation-based prediction model of the circular draw-bead is developed using the Box-Behnken design with selected shape parameters such as the bead height, the shoulder radius and the sheet thickness. The value of DBRF obtained from each design case by analysis is approximated by a second order regression equation. This equation can be utilized to the calculation of the restraining force and the determination of the draw-bead shape as a prediction model. For the evaluation of the prediction model, the optimum design of DBRF in sheet metal forming is carried out using response surface methodology. The suitable type of the draw-bead is suggested based on the optimum values of DBRF. The prediction model of the circular draw-bead proposes the design method of the draw-bead shape. The present procedure provides a guideline in the tool design stage for sheet metal forming to reduce the cost of the product development.

• Korean Chemical Engineering Research
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• 제58권2호
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• pp.266-272
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• 2020

본 연구에서는 갑각류의 껍질로부터 추출한 chitosan으로부터 황산을 촉매로 사용하여 가수분해 및 에스테르화 반응과 반응표면분석 실험계획법을 적용하여 화학 원료 및 연료로 사용 가능한 ethyl levulinate의 생산 가능성을 조사하였다. 반응물 중 수분함량의 영향을 조사한 결과, chitosan의 가수분해와 동시에 탈수반응과 ethyl levulinate로의 에스테르화와 반응은 5% 수분함량에서 가장 높았다. 반응표면분석 실험계획법을 이용하여 반응인자를 최적화한 결과, 200 ℃, 3.19% chitosan, 0.49M 황산 촉매, 5% 수분함량(95% 에탄올 용매), 그리고 58분의 반응조건에서 30.1%의 ethyl levulinate의 생성 수율을 얻었다. 또한, ethyl levulinate의 생성 수율은 반응의 가혹도가 증가할수록 증가하는 경향을 나타내었다. 이러한 결과는 chitosan이 화학 원료 및 연료의 생산에 사용될 수 있는 바이오매스로서의 잠재력이 있다고 판단된다.

• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.92-99
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• 2012

The optimal physical factors affecting enzyme production in an airlift fermenter have not been studied so far. Therefore, the physical parameters such as aeration rate, pH, and temperature affecting PLA-degrading enzyme production by Actinomadura keratinilytica strain T16-1 in a 3 l airlift fermenter were investigated. The response surface methodology (RSM) was used to optimize PLA-degrading enzyme production by implementing the central composite design. The optimal conditions for higher production of PLA-degrading enzyme were aeration rate of 0.43 vvm, pH of 6.85, and temperature at $46^{\circ}C$. Under these conditions, the model predicted a PLA-degrading activity of 254 U/ml. Verification of the optimization showed that PLA-degrading enzyme production of 257 U/ml was observed after 3 days cultivation under the optimal conditions in a 3 l airlift fermenter. The production under the optimized condition in the airlift fermenter was higher than un-optimized condition by 1.7 folds and 12 folds with un-optimized medium or condition in shake flasks. This is the first report on the optimization of environmental conditions for improvement of PLA-degrading enzyme production in a 3 l airlift fermenter by using a statistical analysis method. Moreover, the crude PLA-degrading enzyme could be adsorbed to the substrate and degraded PLA powder to produce lactic acid as degradation products. Therefore, this incident indicates that PLA-degrading enzyme produced by Actinomadura keratinilytica NBRC 104111 strain T16-1 has a potential to degrade PLA to lactic acid as a monomer and can be used for the recycle of PLA polymer.

• 대한기계학회논문집A
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• 제37권11호
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• pp.1397-1405
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• 2013

본 연구에서 탑승자 머리 보호를 위한 센터 필라 트림의 리브 패턴 최적설계는 두 가지 방법에 의해 수행된다. 첫째는 실험계획법과 반응표면법을 이용한 근사최적화 기법으로써, 상대적으로 큰 비중을 차지하는 해석비용 저감을 위하여 근사모델 구성에 필요한 최소한의 해석만을 수행하고 실제 최적화 과정에는 구성된 모델을 이용함으로써 근사적으로 최적 점을 찾아가는 방법이다. 하지만 이러한 방법은 시행착오적인 반복과정을 거쳐야 하는 단점이 있다. 따라서 저자들의 선행연구에서 제안한 순차적 실험계획법과 인공신경망을 이용하여 인자의 상한 또는 하한에 걸리지 않는 근사최적 해를 체계적인 반복과정을 통해 도출하고자 하며, 이를 수학적인 예제와 구조물 문제에 적용함으로써 실용성을 확인하고자 한다.

• 공업화학
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• 제7권6호
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• pp.1147-1155
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• 1996

Wheel형 분무건조기에서 식품첨가제로 사용되는 치즈분말의 건조공정을 반응표면법에 의하여 원료의 고형분함량, wheel 회전속도 및 출구온도를 독립변수로 하고 분말제품의 수분함량, 겉보기밀도, 분말 입자크기 및 현탁액의 점도를 종속변수로 하여 중심합성계획법에 따라 분산분석한 후 유의성과 상관관계를 검증하였다. 독립변수와 종속변수들의 상관관계를 검증한 결과 입자크기와 수분함량은 wheel의 회전속도가 커질수록 감소하였고, 겉보기밀도는 출구온도가 높아짐에 따라 감소하였다. 현탁액의 점도는 wheel의 회전속도와 고형분함량이 커짐에 따라 증가하였다. 분말제품의 종속변수들의 상관관계에서 수분함량과 겉보기밀도는 비례 관계, 입자크기는 수분함량과 겉보기밀도와 반비례의 관계를 나타내었다.