• Investigative Magnetic Resonance Imaging
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• v.12 no.1
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• pp.33-39
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• 2008

Purpose : There is debate concerning the observation of metabolite changes on MRS at the designated cortex during some tasks. The purpose of this study is to assess the change of the lactate content at the motor cortex during hand-grasping tasks with performing real-time fMRI-guided fMRS. Materials and Methods : Seven healthy volunteers (23-28 years old) underwent realtime fMRI during right hand grasping tasks with using a 1.5 T system. After confirming the activating area, single voxel MRS was preformed at 1) the baseline, 2) during the task and 3) after the task on the activating cortex. The three consecutive spectra were compared for observing the changes of the lactate content by the tasks. The Cho/Cr, NAA/Cr and Lac/Cr ratios were calculated manually from those spectra. Results : MRS during the tasks revealed the lactate peaks at the 1.33 ppm resonance frequency with great conspicuity at the activated area, which was identified on the real-time fMRI. After the task scan, the lactate peaks completely disappeared and the spectra recovered to the values of the baseline scan in all volunteers. At baseline, during the task and after the task, the Cho/Cr ratios were 0.81, 0.76 and 0.77, respectively, and the NAA/Cr ratios were 1.68, 1.65 and 1.72, respectively, and the Lac/Cr ratios were 0.28, 0.41 and 0.30, respectively. During the task, Lac was significantly increased by 46%. Conclusion : We observed prominent lactate peaks on MRS during hand-grasping tasks at the activated area, as was shown on the real-time fMRI. We suggest that fMRS can be used as a sensitive tool for observing the metabolite changes of the functioning brain.

• Proceedings of the Korean Society of Life Science Conference
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• 2002.05a
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• pp.9-16
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• 2002

농산부산물 중 식품화 요건이 비교적 적합한 곶감부산물을 기능성 소재로 활용하고자 전처리에 따른 유용성분인 카로티노이드의 함량변화를 조사하였다. 조추출물의 항고혈압활성 및 동물실험에 의한 항당뇨 및 지질대사 개선 효과를 조사하였다. 1. 농산부산물의 기능성 식품화에는, 함유 성분의 특정 생체 기능성, 수집성, 함수율, 안전성 등의 요건이 만족될 필요가 있다. 2. 입도와 건조온도에 따라 보존기간 중 감피의 총카로티노이드와 베타카로틴의 함량은 60일 후에 80% 정도 감소하였으며 입도가 적을수록 감소폭이 컸다. 3. 감과피의 메탄올 조추출물에 대한 항고혈압성은 $11.76{sim}58.61%$의 저해활성을 보여 품종별로 다소 차이를 보였다. 4. Streptozotocin으로 당뇨를 유도한 실험쥐에 대하여 감껍질 분말의 혈당강화 및 지질대사의 개선능력을 검정한 결과 혈당치, 총지질 및 중성지질, 총콜레스테롤의 함량이 대조구에 비하여 유의적으로 낮았다.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.75-80
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• 2020

This study was conducted to compare the functional component content, antioxidant activity, and nitric oxide (NO) inhibition effect of non-enzyme treated, enzyme-treated, and commercial noni juice samples. Enzyme-treated noni juice samples were prepared by cellulase (0.1%) and pectinase (0.1%) treatment of unripe fruits (EUN) and ripe fruits (ERN). Total polyphenol content of the noni juice samples ranged between 0.36 and 1.61 mg/mL. The EUN had the highest total polyphenol content (1.61 mg/mL), while the ERN had the highest scopoletin content (123.88 ㎍/mL) and the highest antioxidant activity. Nitric oxide levels in ERN and NJ5 were lower (55.95 and 60.14%, respectively) than those in other samples. Based on these observations, it was confirmed that enzyme treatment could improve the functional component content and physiological activity of noni juice. In particular, EUN prepared using the ripened noni fruit is expected to have greater utilization value due to its enhanced functionality.

• Food Science and Preservation
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• v.15 no.3
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• pp.361-366
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• 2008

This study was investigated the functional characteristic change by the enzymatic hydrolysate to improve the functionality of soybean milk. The soymilk (SM), hydrolysates of soy milk (HSM), whole soy milk (WSM) and hydrolysates of whole soy milk (HWSM) revealed composition difference whether the bean-curd removal was included or not, but nearly no change was found by the low molecule enzyme treatment. The chromaticity revealed clear difference whether the bean-curd was removed or not, but did not show any difference by the hydrolyzation. Total free sugar and oligosaccharide content was found to be 1,389.88 mg% in SM, 1,013.51 mg% in HSM, 1,539.51 mg% in WSM, and 1,331.53 mg% in HWSM by showing the reduction after the enzyme hydrolyzation. DPPH free radical scavenging activity revealed to show high activity in HSM and in HWSM which were enzymatically hydrolyzed by 49.26% and 45.34%, respectively. And the ACE inhibition activity of HSM and HWSM was found to be approximately 1.6 times higher than the control SM and HSM The superoxide radical scavenging activity revealed to show high activity at HSM and HWSM, and no difference was found by the removal of bean-curd from raw soybean. Based upon these results, the functional characteristics of HSM, WSM and HWSM were found to be excellent compared to SM and it is expected to be used as various functional sources in a future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.43-48
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• 2000

Upon the Preparation of activated carbon fiber(ACF) using chemical activation method and vapour activation method, the fiber obtained from the vapour activation method shows excellent surface Properties. The preparation of antibacterial activated carbon fiber was tried to open the new areas in application of carbon materials. The BET specific surface area and the average pore radius of the antibacterial ACFs were in the range of 844.27~1575.6 $cm^2$/g and 10.6~12.9 (equation omitted), respectively. From the adsorption studies on the antibacterial ACFs, typical Type I isotherms were obtained. And, from the SEM morphology results, it was observed that the surface of ACFs was partially coated by antibacterial materials after the treatment. Finally, from the antibacterial effects of antibacteral ACFs against E. coli, excellent antibacterial activity was shown. Concerning the above results, antibacterial ACFs can have wide application in the areas of sterilization, anti-fragrant. anti-insects.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.885-889
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• 2012

In this study, amine and metal oxide additives were investigated to improve $CO_2$ adsorption capacity of activated carbons (ACs). The characteristics of surface modified ACs were studied by X-ray photoelectron spectroscopy (XPS), $N_2$ adsorption, X-ray diffraction (XRD), and BET. Amine surface treatment decreased specific surface area and pore volume of ACs, but increased alkalinity by the incorporated nitrogen functional groups. Adsorption capacities of amine functionalized ACs was larger than original ACs, because basic group which can react with $CO_2$ was grafted on the ACs surface. Presence of copper oxides on ACs also enhances the carbon dioxide adsorption. The copper oxides could increase the adsorption rate of carbon dioxides due to the acid-base interaction (or electron acceptor-donor interaction). It was found that copper oxide loading was a promising method to improve the $CO_2$ adsorption capacity of ACs.

• Progress in Medical Physics
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• v.15 no.3
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• pp.128-133
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• 2004

The fMRI response of the somatosensory cortex was investigated with vibrotactile stimulation. Three different frequencies of 8, 15, or 25 Hz were applied in order to mainly focus on the hemodynamic response of Meissner corpuscles sensitive to frequencies of 5-40 Hz. A closed-system, pneumatically-driven, rubber diaphragm was fabricated that overcame many of the limitations of existing vibrotactile devices and produced robust sensory cortex activation in an fMRI experiment. Increasing frequency vs. activation area was analyzed in terms of signal percent change and number of pixels. Our preliminary results indicated that the distribution of the signal percentage change widened and more activated pixels were obtained with higher frequencies.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.109-113
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• 1997

Purpose: To evaluate the differences of functional imaging patterns between conventional spoiled gradient echo (SPGR) and echo planar imaging (EPI) methods in cerebral motor cortex activation. Materials and Methods: Functional MR imaging of cerebral motor cortex activation was examined on a 1.5T MR unit with SPGR (TRfrE/flip angle=50ms/4Oms/$30^{\circ}$, FOV=300mm, matrix $size=256{\times}256$, slice thickness=5mm) and an interleaved single shot gradient echo EPI (TRfrE/flip angle = 3000ms/40ms/$90^{\circ}$, FOV=300mm, matrix $size=128{\times}128$, slice thickness=5mm) techniques in five male healthy volunteers. A total of 160 images in one slice and 960 images in 6 slices were obtained with SPGR and EPI, respectively. A right finger movement was accomplished with a paradigm of an 8 activation/ 8 rest periods. The cross-correlation was used for a statistical mapping algorithm. We evaluated any differences of the time series and the signal intensity changes between the rest and activation periods obtained with two techniques. Also, the locations and areas of the activation sites were compared between two techniques. Results: The activation sites in the motor cortex were accurately localized with both methods. In the signal intensity changes between the rest and activation periods at the activation regions, no significant differences were found between EPI and SPGR. Signal to noise ratio (SNR) of the time series data was higher in EPI than in SPGR by two folds. Also, larger pixels were distributed over small p-values at the activation sites in EPI. Conclusions: Good quality functional MR imaging of the cerebral motor cortex activation could be obtained with both SPGR and EPI. However, EPI is preferable because it provides more precise information on hemodynamics related to neural activities than SPGR due to high sensitivity.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.103-117
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• 2017

The aim of this study was to evaluate the effect of green tea extract on probiotic potential, physico-chemical and functional properties of yogurt fermented with Lactobacillus acidophilus D11 or Lactobacillus fermentum D37 strains isolated from Doenjang. Probiotic activities such as the resistance to artificial digestive juices and the ability to adhere to epithelial cells were slightly higher in yogurt supplemented with green tea extract than in plain yogurt, which may be attributed to the increase in the number of lactic acid bacteria (LAB) by green tea extract supplementation. Furthermore, the microbiological and physico-chemical properties such as the number of LAB, organic acid production and viscosity were significantly (P<0.05) increased in yogurt added green tea extract compared to plain yogurt fermented with L. acidophilus D11. However, the green tea extract did not significantly (P>0.05) affect these properties of yogurt fermented with L. fermentum D37 strain. Meanwhile, the antibacterial activities against Escherichia coli O157 ATCC 43889, Salmonella enteritidis ATCC 13076, and Salmonella typhimurium KCTC 2514 and antioxidant activities including total phenol content, radical scavenging ability, and ferric-reducing antioxidant power were significantly higher in plain yogurt fermented with L. fermentum D37 than with L. acidophilus D11. The antibacterial and antioxidant activities of the yogurt were significantly (P<0.05) increased in proportion to the concentration of green tea extract added to plain yogurt. Consequently, green tea yogurt fermented with L. acidophilus D11 or L. fermentum D37 was considered to be a useful functional food that can inhibit the growth of pathogenic bacteria and scavenge the free radicals from the body cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.559-565
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• 2002

The physiological functionalities such as antimicrobial activity, antioxidative activity, angiotensin-I converting enzyme (ACE) inhibitory activity and bile acid binding capacity were measured for the solvent-fractionated methanol extracts of Alaska pollack sik-hae at various time intervals during fermentation. Two temperature schemes of fermentation were studied: constant temperature of 2$0^{\circ}C$ (A) and stepwise change from 2$0^{\circ}C$ (10 days) to 5$^{\circ}C$ (B). The methanol extracts of Alaska pollack sik-hae showed antimicrobial activities against 9 kinds of micro-organisms including pathogenic and food poisoning strains. Among these, gram positive bacteria, in particular Staphylococcus aureus, showed more sensitivity to the extracts than gram negative bacteria and fungi. Antioxidative activity (EDA$_{50}$) increased until 15 days (A, 0.92 mg/$m\ell$) or 16 days of fermentation (B, 0.94 mg/$m\ell$), and then gradually decreased. ACE inhibitory activity was observed in all fermentation time except 0 day, and bile acid binding capacity at 15 days (A) and 16 days (B) only.