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        검색결과 118

        81.
        2016.08 KCI 등재 서비스 종료(열람 제한)
        Background: In this study, microwave extraction was used, which is an effective method to extract useful bioactive substances as it requires low quantities of solvent and short time periods. The aim of this study was to determine the optimal extraction conditions for Agrimonia pilosa Ledeb. Methods and Results: The independent variables were ethanol concentration, microwave power, and extraction time, each of which had five levels. The dependent variables were total polyphenol and total flavonoid content, and DPPH radical scavenging activity. To determine the optimal extraction conditions for bioactive compounds, a response surface methodology was employed. Contour maps were generated from polynomial equations. The optimal conditions were then assumed by superimposing these contour maps. Based on the resulting graph, the optimal microwave extraction conditions for Agrimonia pilosa Ledeb were determined as 42 - 48% ethanol concentration, 240 - 280W microwave power, and 13 - 20 min of extraction time. Conclusions: Ethanol concentration had a significant effect on microwave extraction, in terms of total polyphenol and total flavonoid content, as well as DPPH radical scavenging activity. Microwave power and extraction time influenced the total polyphenol content, but not the total flavonoid content or the DPPH radical scavenging activity.
        82.
        2015.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구는 식혜의 편이성, 유통성, 저장성을 향상시키기 위하여 피막물질을 첨가하고 분무건조를 통하여 분말화를 하고자 하였다. 최적조건 설정을 위하여 반응표면분석법을 이용하였으며 독립변수는 피막물질 maltodextrin의 첨가량 (%), 분무건조기의 inlet 온도(℃) 그리고 분무건조기내 시 료의 공급속도(mL/min)로 설정하였으며 이에 따라 영향을 받는 반응변수는 분말의 흡습량(g), 용해도(%), 입자크기(μ m)로 설정하였다. 각 반응변수에 따른 회귀식은 흡습량은 p<0.001, 용해도는 p<0.05, 입자크기는 P<0.001 수준에서 유의성이 인정되었다. 그리고 각 독립변수와 종속변수의 영향을 나타내는 반응표면그래프를 이용하여 최적 분말화 조건을 예측한 결과 각 종속변수 최적점인 MD 22%, 분무건 조기의 inlet 온도 140℃ 그리고 분무건조기 내로 유입되는 시료의 공급속도는 51 mL/min로 예측되었다.
        83.
        2015.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        ANOVA 분석을 통해 건조온도와 건조시간이 열풍건조 와 냉풍건조의 중요변수임을 알 수 있었으며 복분자의 반건 조를 위해서는 열풍건조의 경우 65.8℃, 4.3시간이 적당하 였고 냉풍건조의 경우 비슷한 정도의 건조수분함량까지 28.2시간이 걸렸다. 그러나 건조온도가 높아지면 vitamin C와 ellagic acid의 함량이 줄어드는 등 품질적 열화가 심하 게 나타났다. 또한 생리활성물질들은 냉풍건조에서 전반적 으로 더 잘 보존 되었으며 총폴리페놀의 함량에서는 더욱 그러하였다. 따라서 냉풍건조방법은 고품질의 반건조 복분 자 제조에 적합한 건조방법이며 최적 건조조건은 21.3℃, 28.2시간으로 나타났다.
        87.
        2013.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        In this study, we investigated the contents of total polyphenol (TP), total flavonoid, and absorbance at 475 nm (OD475) which may produced in solid-fermented leaf of Smilax china L. by Aspergillus oryzae as a new functional components with reddish brown color, contents of water soluble substance (WSS), electron donating ability (EDA), Hunter L*, a*, b* values, sensory overall acceptability (OA) and also, the inhibitory activities (XOI and AOI) against partial purified xanthine oxidase (XO) and aldehyde oxidase (AO) from rabbit liver which were well known to relate the gout, and alcoholic liver disease, respectively in order to optimize water extraction using response surface methodology (RSM). All the R2 values of the second-order polymonials ranged from 0.85 to 0.98, except for the EDA (0.69) and the XOI (0.78). However, the activities of the EDA and XOI were relatively high in the lower concentration of the fermented Smilax china L. leaf. The effects on the water extraction were highest in the concentration, among the dependent variables, and showed significant differences at the 1% level in the TP, TF and WSS contents and the a*, b* and OD475 values, but the OA showed significant differences at the 5% level. The optimal values of AOI, which was the most important functionality in the Smilax china L. that was predicted via RSM, were 59.48% at the 2.19% concentration, a 90.02°C extraction temperature and a 4.03 minute extraction time (R2: 0.93, p<0.007). The ranges of all the dependent variables of the optimal water extraction were 1.6~1.8% for the concentration, 83~93°C for the temperature and 3.4~4.4 minutes for the extraction time; and the optimal water extraction conditions were a 1.7% concentration, an 88°C extraction temperature and a 3.9-min extraction time.
        89.
        2013.03 KCI 등재 서비스 종료(열람 제한)
        Acid hydrolysis of cellulose using hydrothermal reaction was conducted to maximize reducing sugar concentration and the response surface methodology (RSM) was applied to study the effects of independent variables, such as reaction temperature (116 ~ 184oC), reaction time (12 ~ 28 min) and hydrochloric acid concentration (HCl, 0.0159 ~ 0.1841 N) on reducing sugar concentration and production yield from the cellulose. With the optimum conditions of the acid-catalyzed hydrothermal hydrolysis, the reducing sugar (RS) was obtained as 369.14 mg-RS/g-cellulose in 172.77oC of the reaction temperature, 28.41 min of the reaction time and 0.067 N of the hydrochloric acid concentration. The glucose (Glu) was obtained as 281.94 mg-Glu/g-cellulose in 154.70oC of the reaction temperature, 11.59 min of the reaction time and 0.184 N of the hydrochloric acid concentration.
        90.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Response surface methodology was applied to the processing conditions to investigate the physicochemical properties of ramie porridge. In the processing conditions based on the central composite design with the addition of ramie leaf powder (0-4 g) and water (700-1100 g), the coefficients of determination (R2) of the models were above 0.9141 for the physicochemical properties, above 0.7627 for the Hunter color parameters, and above 0.8975 for the rheological properties. The soluble solid content, viscosity, and gumminess of the sample decreased significantly with an increase in the water added, whereas the spreadability and adhesiveness increased significantly. The Hunter color L value of the sample decreased significantly with an increase in the amount of ramie leaf powder added, whereas the Hunter b value increased significantly. The estimated maximum viscosity of the ramie porridge was shown to be 24,643 cp when 1.90 g ramie leaf powder and 700.24 g water were added; the estimated maximum lightness of the ramie porridge was shown to be 59.11 when 0.02 g ramie leaf powder and 869.30 g water were added; and the estimated maximum gumminess of the ramie porridge was shown to be 21.46 g when 2.12 g ramie leaf powder and 700.35 g water were added.
        91.
        2012.08 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study was conducted to establish the extraction conditions for the optimization of the biological activities of black garlic using the response surface methodology (RSM). The extraction conditions were based on the central composite design, with 15 kinds of variations in the extraction temperature (50-90℃), extraction time (3-15 hrs), and ethanol concentration (0-100%). The total phenol, flavonoids, thiosulfinate contents, and anti-oxidant activity of black garlic extract were significantly higher at the J condition (90℃ for 9 hrs with a 50% ethanol concentration). In this condition, the biological activities such as DPPH radical scavenging (66.10%), ABTS radical scavenging activity (75.02%), and reducing power by of FRAP (375.4 μM/mL) were excellent. Overall, the extraction conditions for the optimized biological activities of black garlic via RSM were expected to be at 89.68℃ for 9.79 hrs with a 55.72% ethanol concentration. The actual values were 96.4-114.8% of the predicted values.
        92.
        2012.08 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Enzymatic action and microbial growth degrade the quality of fresh-cut lettuce. Browning, a bad smell, and softening during storage are the major forms of quality deterioration. Health-oriented consumers tend to avoid foods treated with chemicals to maintain their freshness. This study was conducted to evaluate the change in the quality of fresh-cut lettuce with combined low-temperature blanching (LB) and ultrasonication (US). The optimum condition was selected using the response surface methodology (RSM), through a regression analysis with the following independent variables; the ultrasonication time (X1), blanching temperature (X2), blanching time (X3), and dependent variable; ΔE value (y). It was found that the condition with the lowest ΔE value occurred with combined 90s US and 45℃ 90s LB (US+LB). The combined treatment group (US+LB) was stored at 10℃ for 9 days with the control group and each single-treatment group, with low-temperature blanching and ultrasonication. Overall, the US+LB group had a significantly high L* value, which indicates significantly low a*, b*, ΔE, browning index, PPO, and POD activity values, and a low total bacteria count (p < 0.05). The US+LB group also had the highest sensory score (except for aroma and texture; p > 0.05).
        94.
        2011.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 실험은 반응표면분석법을 이용하여 진피 에탄올 추출물의 이화학적 특성을 모니터링 하였다. 진피의 에탄올 추출조건의 최적화를 위하여 예비실험 결과에 따라 요인변수들 중 시료대 용매비를 20 mL/g로 고정하여 반응표면을 나타내었다. 추출조건에 따른 수율 및 총 폴리페놀함량의 최대값은 예측된 정상점에서 능선분석을 실시하여 본 결과, 36.31%와 13.86 mg/mL이었다. 추출조건별 총 플라보노이드함량은 3.19~6.67 mg/mL의 범위였으며,
        95.
        2011.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Camellia oil과 palmitic, 그리고 stearic ethyl ester를 기질로 하고 Lipozyme TLIM을 촉매로 이용하여 interesterification을 통한 POS를 많이 함유한 반응물을 합성하고자 하였다. 반응 조건(반응효소비율, 반응시간, 기질의 비율)을 독립변수로 하여 중심 합성 계획에 의한 반응 표면 분석을 통하여 POS의 함량은 높이고, sn-2 position의 acyl migration을 낮추어 합성하는
        96.
        2011.07 KCI 등재 서비스 종료(열람 제한)
        This study investigated the application of experimental design methodology to optimization of conditions of air-plasma and oxygen-plasma oxidation of N, N-Dimethyl-4-nitrosoaniline (RNO). The reactions of RNO degradation were described as a function of the parameters of voltage (X1), gas flow rate (X2) and initial RNO concentration (X3) and modeled by the use of the central composite design. In pre-test, RNO degradation of the oxygen-plasma was higher than that of the air-plasma though low voltage and gas flow rate. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the RNO removal efficiency and test variables in a coded unit: RNO removal efficiency (%) = 86.06 + 5.00X1 + 14.19X2 - 8.08X3 + 3.63X1X2 - 7.66X2 2 (air-plasma); RNO removal efficiency (%) = 88.06 + 4.18X1 + 2.25X2 - 4.91X3 + 2.35X1X3 + 2.66X1 2 + 1.72X3 2 (oxygen-plasma). In analysis of the main effect, air flow rate and initial RNO concentration were most important factor on RNO degradation in air-plasma and oxygen-plasma, respectively. Optimized conditions under specified range were obtained for the highest desirability at voltage 152.37 V, 135.49 V voltage and 5.79 L/min, 2.82 L/min gas flow rate and 25.65 mg/L, 34.94 mg/L initial RNO concentration for air-plasma and oxygen-plasma, respectively.
        97.
        2011.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        반응표면분석법에 의해 생두를 실험 조건인 의 온도 범위에서 7.93~22.07분의 조건으로 커피원두를 배전하여 이화학적 분석, 물리적 특성, 관능검사 등을 실시하여 최적 조건을 설정하였다. 배전 정도가 커짐에 따라 직경, 길이, 두께 모두가 증가하여 전체적인 팽창률은 증가했지만, 겉보기 밀도의 변화는 그 차이가 적은 것으로 나타났다. pH는 증가하는 반면 총산도와 총페놀함량은 감소하는 경향을 나타내었으며, 고형분함량은 증가하는 유의성을 가지고 있
        98.
        2010.05 KCI 등재 서비스 종료(열람 제한)
        Security robot has gradually developed and deployed in order to protect civilian’s lives as well as fortune and subjugate the shortcomings of CCTV which lacks of mobility. We have developed a security robot for outdoor environment and the main purpose of the driving mechanism is to overcome the bumps or projections with high speed. The robot platform consists of 4 omnidirectional wheel-based driving mechanisms and suspension for each driving mechanism. In this paper, principal suspension parameters of outdoor security robot for overcoming obstacles with stability are studied and approximately optimized using Response Surface Methodology (RSM) since it is difficult to find the exact relationship between suspension parameters and the shock, which is significantly associated with stability of the robot, at the robot platform. Simulation using ADAMS is conducted for assessing the feasibility of optimized design parameters.
        99.
        2010.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구는 세이지의 다양한 생리적 기능성과 우리 전통된장을 접목하여 허브를 첨가한 된장을 개발하고자 된장의 염도와 세이지분말 첨가량을 달리한 후 반응표면분석법으로 최적조건을 얻고자 관능특성을 조사하였다. 그 결과, 색은 1.20~2.70, 냄새는 1.60~3.20, 맛은 1.40~3.50, 조직감은 1.60~3.50, 전반적인 기호도는 1.60~3.05의 값을 나타내어 실험구의 조건에 따라 차이를 보였다. 이차회귀식에 의하여 형성된 반응표면 분석
        100.
        2010.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구에서는 국내산 사과의 주스 가공과정에서 patulin 함량 최소 방법을 모니터링 하였다. 중심합성계획법으로 ascorbic acid 첨가량(100, 200, 300 및 400 ppm)과 활성탄 사용량(50, 100, 150 및 200 ppm)을 독립변수로 설정하고 각각의 조건에서 사과주스를 제조한 결과 patulin 잔류량은 ascorbic acid 함량 237.77 ppm, 활성탄 함량 106.58 ppm에서 최소점을 나타내었다가 점차
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