Subcritical water extraction (SWE) of anthocyanin from blueberries (Vaccinium corymbosum)

Hye-Ji Kang,Seon-Woo Kim,Ha-Un Yoo,Na-Yeon Kim,So-Yoon Yee,Min-Jung Ko,Myong-Soo Chung 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

Subcritical water extraction (SWE) is an eco-friendly new extraction technology because it does not contain harmful organic solvent and has high extraction efficiency in a short time compared with conventional extraction methods. Blueberries (Vaccinium corymbosum) are widely known as superfood due to rich source of anthocyanin (malvidin-3-o-galgctoside) and antioxidant activity. In this study, optimal extraction condition of SWE from blueberries was determined and compared with the conventional extraction methods. SWE was carried out using a Dionex Accelerated Solvent Extractor (ASE, Model 350) under conditions of temperatures (110, 130, 150 and 170°C) and times (1, 3, 5 and 10 min). Total anthocyanin of SWE extracts was compared with hot water (60°C, 1 h) extract and pressed juice extract. The total anthocyanin content was determined by pH differential method. Considering both the extraction time and temperature conditions, the highest content of total anthocyanin content was 0.455 mg/g FW Vaccinium corymbosum at 130°C for 3 min. At high temperature and long extraction time, the anthocyanin in the blueberries will undergo thermal degradation due to low stability of anthocyanin at extreme condition. Besides, maximum yield of anthocyanin from blueberries using SWE was about 1.2 and 3.8 times more higher than hot water extract and pressed juice extract, respectively. Therefore, SWE is faster and more efficient method to extract anthocyanin from blueberries than conventional extraction methods. This study shows a possibility of SWE applied to food processing industry.

자몽껍질 유래 플라바논의 최적 추출 및 기능성 소재 캡슐화

고민정(Min-Jung Ko),권혜림(Hye-Lim Kwon),정명수(Myong-Soo Chung) 한국식품과학회 2014 한국식품과학회지 Vol.46 No.4

버려지는 자몽 껍질에 다량 함유되어있는 플라바논을 추출하여 기능성 성분을 재이용하였다. 친환경용매인 아임계수 추출기술을 이용하여 170℃, 10 min의 최적 조건에서 추출함으로써 무독성 용매로 빠르고 경제적으로 추출할 수 있었다. 자몽껍질 추출물을 β-cyclodextrin을 이용하여 처리함으로써 플라바논과 같은 비극성 물질을 캡슐화하여 소재의 가용화를 용이하게 하였다. 이것은 항산화 기능이 향상된 대체 소재의 개발 및 건강지향식품에 이용할 수 있으며, 이를 통하여 세계 기능성 식품 시장으로의 진출을 위한 발판으로도 삼을 수 있을 것으로 기대된다. The extraction of flavanones such as naringin, narirutin, naringenin, hesperidin, and hesperetin from grapefruit peels was performed using subcritical water extraction (SWE), hot water extraction, and conventional methods such as methanol and ethanol extraction. We analyzed the total flavanone content using high-performance liquid chromatography (HPLC) for each extracting method. Among the three methods, SWE was the optimal method with optimal operating conditions of 170℃ temperature and 10 min operating time. The maximum total flavanone extracted was 86.539±3.52 mg/g grapefruit peels. Moreover, we treated the extracts with 60% β-cyclodextrin and then analyzed the surface structure of the encapsulated compounds by field emission-scanning electron microscopy (FE-SEM). The results indicated that the encapsulation in β-cyclodextrin improved solubilization, and the inclusion complex could serve as food supplements.

Improving the subcritical water extraction of flavonoids narirutin and hesperidin from Citrus unshiu peel by pulsed electric fields

Hui-Ju Kim,Mi-Ri Kwon,Hye-Ji Kang,Na-Yeon Kim,Hee-Jeong Hwang,Min-Jung Ko,Myong-Soo Chung 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

Citrus fruit is important source of flavonoids, mainly flavanones which are narirutin and hesperidin. Those citrus flavonoids have been found to have health-related properties including antioxidant, anticancer, and anti-inflammatory. The main purpose of this study was to verify that the extraction of narirutin and hesperidin from Citrus peel can be more effective by combining pulsed electric field (PEF) pre-treatment and subcritical water extraction (SWE). Citrus unshiu peels were treated with PEF under conditions of electric field strength (3 kV/cm) and times (1 and 2 min). Subsequent SWE was conducted by using a Dionex Accelerated Solvent Extractor (ASE, Model 350) at extraction temperature 170°C for 10 min. The total flavonoids content was measured by using the aluminum chloride colorimetric method and the antioxidant capacity was analyzed by the Ferric reducing antioxidant power (FRAP) assay using spectrophotometer. The concentrations of narirutin and hesperidin were increased as PEF pre-treatment time increased. The highest concentrations of narirutin and hesperidin were 13.41 mg narirutin/g dry citrus peel and 141.16 mg hesperidin/g dry citrus peel at PEF pre-treatment condition of 3 kV/cm and 2 min. The total flavonoids contents of the extracts increased 105.2% and 123.1% for citrus peel PEF treated at 1 and 2 min, respectively. In addition, compared to the untreated sample, PEF pre-treatments of 1 and 2 min increased the antioxidant capacity of the extracts 109.2% and 160.8%, respectively. Therefore, the results demonstrate the potential of PEF pre-treatment to improve the SWE of flavonoids from citrus unshiu peel.

김밥과 그 재료의 세균수 측정

강국희,김혜란,고애경,김경민,최선규 성균관대학교 생명과학자원연구소 1994 生命資源科學硏究 Vol.1 No.2

We have investigated the distribution of bacteria in kimbab and its materials. The total bactria counts were over 3×10 exp(6)/g(n=30) when the kimbabs were delivered to restaurant and it exceeded the prieliminary legal level 1 × 10 exp(6)/g even though it should be negative for coliforms. In order to look into the cause of bacterial contamination in kimbabs, we examined the content materials of kimbabs. The bacterial counts were founded 10^4-10^8/g for Kim, 10^4-10^8/g for sausage, 10^4-10^6/g for spinach, 10^3-10^7/g for carrot, and 10^3-10^6/g for danmugi, respectively. From these results it could be concluded that the bacterial contamination in Kimbabs are due to kim, spinach, carrot, and sausage. Therefore, so as to reduce the bacterial contamination for kimbab, the sanitary manufacture and storage of kim and the refrigeration of content materials should be went abreast.

Evaluation of vaccines for the SAT 1, SAT 2, and SAT 3 serotypes of Foot-and-Mouth Disease in pigs

Hye-Eun Jo(Hye-Eun Jo),Su-Hwa You(Su-Hwa You),Joo-Hyung Choi(Joo-Hyung Choi),Mi-Kyeong Ko(Mi-Kyeong Ko),Sung Ho Shin(Sung Ho Shin),Hyundong Jo(Hyundong Jo),Min Ja Lee(Min Ja Lee),Su-Mi Kim(Su-Mi Kim) 한국예방수의학회 2019 한국예방수의학회 학술대회자료집 Vol.2018 No.-

A Genome-Wide and Candidate Gene Association Study between Specific Single Nucleotide Polymorphisms and Preterm Birth in Korean Pregnant Women

( Hye Jin Ko ),( Young Min Hur ),( Jae-young Yoo ),( Young-ah You ),( Sunwha Park ),( Soo Min Kim ),( Gain Lee ),( Young Ju Kim ) 대한산부인과학회 2023 대한산부인과학회 학술대회 Vol.109 No.-

Roles of Aluminum Hydroxide and Monophosphoryl Lipid A Adjuvants in Overcoming CD4⁺ T Cell Deficiency To Induce Isotype-Switched IgG Antibody Responses and Protection by T-Dependent Influenza Vaccine

Ko, Eun-Ju,Lee, Young-Tae,Kim, Ki-Hye,Lee, Youri,Jung, Yu-Jin,Kim, Min-Chul,Lee, Yu-Na,Kang, Taeuk,Kang, Sang-Moo American Association of Immunologists 2017 Journal of Immunology Vol. No.

<P>Vaccine adjuvant effects in the CD4-deficient condition largely remain unknown. We investigated the roles of combined monophosphoryl lipid A (MPL) and aluminum hydroxide (Alum) adjuvant (MPL+Alum) in inducing immunity after immunization of CD4 knockout (CD4KO) and wild-type (WT) mice with T-dependent influenza vaccine. MPL+ Alum adjuvant mediated IgG isotypeswitched Abs, IgG-secreting cell responses, and protection in CD4KO mice, which were comparable to those in WT mice. In contrast, Alum adjuvant effects were dependent on CD4(+) T cells. MPL+ Alum adjuvant was effective in recruiting monocytes and neutrophils as well as in protecting macrophages from Alum-mediated cell loss at the injection site in CD4KO mice. MPL+Alum appeared to attenuate MPL-induced inflammatory responses in WT mice, likely improving the safety. Additional studies in CD4-depleted WT mice and MHC class II KO mice suggest that MHC class II+ APCs contribute to providing alternative B cell help in the CD4-deficient condition in the context of MPL+Alum-adjuvanted vaccination.</P>

수학교육용 애플리케이션의 유형 및 특징

고혜민(Hye-min Ko),이경언(Kyung-eon Lee) 제주대학교 교육과학연구소 2023 교육과학연구 Vol.25 No.2

본 연구는 수학교육용 애플리케이션의 유형별 특징을 분석하는 연구이다. 과거와 유사하게 문제중심형이 가장 많았지만 최근에는 문제중심형과 개념중심형에 학습자의 학습 상태를 분석하는 인공지능 기능이 포함된 유형이 증가하고 있다. 학습 과정 측면에서는 문제를 해결한 후 틀린 문제에 대한 오답 노트를 제공하여 학습자가 실수한 부분을 확인하고 교정할 수 있도록 해주는 경우가 있었다. 오답 문제에 대한 복습의 기회를 제공하여 개념이나 내용에 대한 이해를 증진하는 것은 교실에서 이루어지는 수학 학습뿐만 아니라 수학교육용 애플리케이션에서도 중요한 요소이다. 또한, 초기 애플리케이션은 사전에 프로그램화된 방식에 따라 일방적으로 학습자료가 제시되는 경우가 많았지만, 최근 개발된 수학교육용 애플리케이션 중에는 학습자가 질문하면 그에 대한 답을 제공받거나, 수학 문제를 만들어 입력하고 답을 얻는 등 상호작용적 구성을 활용하고 있는 애플리케이션이 증가하였다. 스마트 환경에서의 학습에서 우려되는 점으로 학습자의 자기주도적 학습 능력이 낮아질 것으로 우려하는 경우가 많은데, 최근 애플리케이션은 학습 결과 분석, 오답노트 제공, 상호작용적 구성을 통하여 학습자 스스로 자기주도적으로 학습을 구성하고 학습 목표를 성취할 수 있도록 구성된 애플리케이션이 증가하고 있다. This study analyzed the characteristics of each type of math education application. Similar to the past study, problem-oriented types were the most common, but recently, the number of types including artificial intelligence functions that analyze learners' learning status is increasing. In terms of the learning process, there were cases where after solving the problem, a wrong answer note for the wrong question was provided so that learners could check and correct the mistakes. Improving understanding of concepts or contents by providing opportunities to review incorrect answers is an important factor in mathematical education applications as well as mathematical learning in classrooms. In addition, early applications often presented learning materials unilaterally according to a pre-programmed method, but among the recently developed math education applications, there were applications that used interactive composition such as receiving answers when learners ask questions, making, typing, and obtaining answers. Self-directed learning by learners is often feared to decrease as a concern in learning in smart environments. Recently, more and more applications are configured to organize learning self-directed and achieve learning goals through AI analysis of learning results, wrong answer notes, and interactive composition.

Reduction-oxidation kinetics of three different iron oxide phases for CO₂ activation to CO

Jeong, Min Hye,Lee, Dong Hyun,Han, Gui Young,Shin, Chae-Ho,Shin, Myoung Kyun,Ko, Chang Kuk,Bae, Jong Wook Elsevier 2017 Fuel Vol.202 No.-

<P><B>Abstract</B></P> <P>The reduction-oxidation characteristics and proper kinetic models of three different iron ores having respective main phases of FeOOH, Fe<SUB>3</SUB>O<SUB>4</SUB>, and Fe<SUB>2</SUB>O<SUB>3</SUB> were investigated using an isothermal method. A proposed kinetic model was well satisfied to explain the experimental data for CO<SUB>2</SUB> activation to CO with a high accuracy. The kinetic data of the different phases of iron ores for its reduction by H<SUB>2</SUB> and for the oxidation by CO<SUB>2</SUB> were relatively well described by a simple three-dimensional diffusion model of Jander equation. Activation energies of three different iron ores with the phase of FeOOH, Fe<SUB>2</SUB>O<SUB>3</SUB>, and Fe<SUB>3</SUB>O<SUB>4</SUB> for the oxidation by CO<SUB>2</SUB> were found to be 42, 25, and 12kJ/mol, respectively. Iron ore having a FeOOH phase exhibited a higher redox property by showing a large amount of CO generation through CO<SUB>2</SUB> activation with an activation energy of 42kJ/mol and a rate constant of 0.0065min<SUP>–1</SUP>. The superior activities on the FeOOH were mainly attributed to a large surface area with medium grain size of FeOOH crystallites by forming a thermodynamically stable Fe<SUB>3</SUB>O<SUB>4</SUB> phase on the outer surfaces even under the reduction-oxidation reaction cycle.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Kinetic model of three different iron phases were investigated for CO<SUB>2</SUB> activation to CO. </LI> <LI> Three-dimensional diffusion Jander equation was well fitted with experimental data. </LI> <LI> Iron ores having a phase of FeOOH showed a superior activity and stability. </LI> <LI> Large surface area with a stable Fe<SUB>3</SUB>O<SUB>4</SUB> phase was formed on the porous FeOOH surfaces. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Mechanical failure mechanism of E-jet printed Ag-grid on Graphene films

Eun-Hye Ko,Hyo-Joong Kim,Ki-Won Seo,Da-Young Cho,Hye-Min Lee,Han-Ki Kim 한국진공학회 2015 한국진공학회 학술발표회초록집 Vol.2015 No.2