• 한국식품과학회지
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• 제36권2호
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• pp.211-216
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• 2004

회분식 반응기(stirred-tank batch reactor)를 사용한 DAG, MAG 함유 기능성유지를 비용매계(solvent-free system) 조건에서 효소적 반응을 이용하여 합성하였다. 48시간 동안 합성된 지질을 HPLC를 사용한 TAG, 1,3-DAG, 1,2-DAG 및 MAG 함량 분석결과 각각 45.05, 16.27, 23.05 및 14.98%로 분석되었으며 체중개선 기능성 유지의 지방산 조성 분석결과 palmitic, palmitoleic, stearic, oleic, linoleic 및 linolenic acid가 13.21, 0.15, 2.02, 34.36, 49.12 및 1.14 mol%로 분석되었다. 합성된 지질의 ${\alpha},\;{\gamma}$ 및 ${\delta}-tocopherol$ 함량을 분석한 결과는 각각 0.014, 0.029 및 0.010%로 분석되었으며 총 tocopherol 함량은 0.053%로 나타났다. 또한 재구성된 지질을 사용하여 산가, 비누화가, 요오드가를 측정하였으며 융점 및 결정화점을 살펴보고 이를 통하여 옥수수유로 유래된 DAG, MAG를 함유한 체중개선 기능성 유지의 이화학적, 물리적 특징을 규명하였다. 체중개선 기능성 유지의 산화 안정성 실험을 시행한 결과 체중개선 기능성 유지가 원료유인 옥수수유보다 높은 과산화물가와 p-anisidine가를 보였으며 각기 달리 혼합한 rosemary추출물(100, 200 및 300ppm)이 체중개선 기능성 유지와 옥수수유의 산화를 감소 시켰다.

• Journal of Nutrition and Health
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• 제31권1호
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• pp.21-27
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• 1998

The objective of this study was to observe the effect of dietary calcium(Ca) level on colonic mucosal levels of cell proliferation, 1, 2-diacylglycerol(DAG), TXB2, PGE2 and phospholipid fatty acid composition which have been known as biomarkers for colon cancer. One hundred male Sprague Dawley rats, at 7 weeks of age, were divided into two fat type groups. Each group of which was further divided into two Ca level groups. Each rt was intramuscularly injected with 1, 2,-dimenthylhydrazine(DMH) for 6 weeks (total dose of 180mg/kg body weight) and simultaneously fed one of four experimental diets containing 15% dietary fat(corn oil or perilla oil )and 0.3% or 1.0% Ca by weight for 20 weeks. Compared to corn oil, perilla oil significantly reduced cell proliferation by decreasing labeling index, proliferating zone, crypt length in colonic mucosa and colonic mucosa and colonic mucosal levels of DAG, TXB2 . PGE2 and phospolipid (PL) arachidonic acid distribution. The effect of Ca on biomarketrs was different depending on the type of dietary fat comsumed . Ca effect of Ca on biomarkers was different depending on the type of dietary fat comsumed. Ca effect was not significantly shown in the PO group, but it was significant in the CO group in which high Ca(1.0%) decreased the levels of levels of PL-C20 : 4(%), DAG and PGE2 . However , high Ca supplementation had shown only the trends of improving cell proliferation. Overall , high dietary Ca significantly reduced cell proliferation by inhibiting the synthesis of eicosanoid and DAG with reduced distribution of PL-C20 : 4 , which may have resulted in lower activation of PKC through reduced signal transduction. Since a high level of dietary Ca was more effective in reducing the risk factor against colon cancer in corn oil fed rats, it could be suggested that a higher amount of dietary Ca be consumed , especially when more vegetable oil rich in linoleic acid is included in the diet.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.375.4-376
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• 2002

Acyl CoA:diacylglycerol acyltransferase (DGAT) is a key enzyme involved in triacylglycerol synthesis. Too much accumulation of triacylglycerol in certain organs and tissues of the body causes high risk conditions of fatty liver. obesity and hypertriglyceridemia. leading to serious diseases of atherosclerosis. Therefore, DGAT inhibition may be worthwhile strategy for the treatment of triglyceride metabolism disorders. such as obesity or hypertriglyceridemia. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.267.1-267.1
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• 2003

Diacylglycerol acyltransferase (DGAT) is a microsomal enzyme that plays a central role in the metabolism of cellular glycerolipid. Recently, the generation of DGA T-deficient mice has provided a better understanding of triglyceride synthesis and its relationship to obesity. Therefore DGAT is an attractive target for treatments of triglyceride metabolism disorders, such as obesity or hypertriglyceridemia. (omitted)

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.142.1-142
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• 2003

Mono-, diacylglycerol were synthesized by glycerolysis of bran oil and glycerol using IM60 (an immobilized lipase) in a stirred batch reactor for 72 hours. After glycerolysis, the composition TAG, DAG, MAG in product was 41.7%, 44.7%, and 11.1%, respectively. Glycerol was separated, then this mixture product was undergone fractionation for winterization followed. The fractionation was performed using hexane and acetone solvent to reduce palmitic acid at the low temperature for overnight individually. Temperature was set -40$^{\circ}C$, -14$^{\circ}C$, -8$^{\circ}C$ and 0$^{\circ}C$, respectively. By considering results from this experiments, fractionation with hexane at -8$^{\circ}C$ was most efficient regarding to yield without crystallization.

• 한국식품과학회지
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• 제51권3호
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• pp.272-277
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• 2019

본 연구진은 선행연구에서 MCE-DAG를 섭취한 마우스에서 혈중 총 콜레스테롤과 LDL 콜레스테롤의 감소를 보고한 바 있어, 본 연구에서 in vitro를 통해 MCE-DAG와 간의 콜레스테롤 항상성 기전의 관련성을 구명하고자 하였다. LDLR과 같은 콜레스테롤 흡수 관련 인자의 발현이 MCE-DAG에 의해 증가한 반면, LDLR을 억제하는 PCSK9의 발현은 감소하였다. 또한, 콜레스테롤 합성 관련 인자인 HMGCR의 발현이 MCE-DAG에 의해 증가하였고, 전사조절인자인 SREBP2의 발현이 증가하였다. 이러한 결과들은 콜레스테롤의 합성과 흡수가 동시에 증가하였음을 뒷받침한다. 즉, 간 내 콜레스테롤 필요량이 증가함에 따라, 간의 콜레스테롤 합성 및 흡수를 활성화시켜 콜레스테롤 항상성을 유지하는 기전이 촉진되었음을 의미한다. 하지만 간 세포 내 총 콜레스테롤 양은 MCE-DAG에서 영향을 받지 않았다. 콜레스테롤 흡수 및 합성 기전이 촉진되었음에도 세포 내 콜레스테롤 농도가 증가하지 않은 현상은 담즙산 등 콜레스테롤 분비 촉진에 의한 것일 수 있다. 이러한 추론은 추후 콜레스테롤 분비 기전을 검증할 수 있는 실험을 설계하여 검증해볼 필요성이 있다. 결론적으로 MCE-DAG는 세포 내 콜레스테롤 흡수 작용을 촉진하는 효과가 있어 추후 기능성 유지로 활용 가능할 것으로 판단된다.

• 한국식품과학회지
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• 제42권2호
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• pp.246-249
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• 2010

Glycerol과 oleic ethyl ester와의 반응, 그리고 glycerol과 oleic acid와의 반응에서는 DAG가 생성되지 않았었지만 GMO와 SBO를 기질로 사용한 반응에서는 DAG가 생성됨을 확인하였다. 기질의 몰 비율에 따른 DAG 생성율을 비교하기 위하여 효소량을 기질 질량의 20%로 동일하게 설정하고 SBO와 GMO의 몰비율을 각각 2:1, 1:1과 1:2로 하여 반응한 결과, 1 hr 후 DAG의 함량이 최대로 도달 하였고 그 후에는 큰 차이를 보이지 않았다. 1hr에서 가장 큰 DAG 함량을 보인 몰비율은 1:1과 1:2(SBO:GMO)일 때로 각각 20.0, 20.4 g/100 g oil로 나타났고, 이 두 몰비율 중 TAG 함량이 낮았던 1:2 몰비율을 이용하여 DAG를 합성 하였다. 한편, 효소의 사용량에 따른 DAG 생성율을 비교하기 위하여 SBO와 GMO의 몰비율을 1:2로 동일하게 설정하고 효소량을 기질 질량의 2, 5, 10, 20%로 하여 반응한 결과, 1 hr의 DAG 함량은 각각 10.8, 14.0, 16.9, 20.4 g/100 g oil로 나타났다. 1 hr 이후의 DAG 생성량을 보면 효소량을 20% 사용한 경우, 72 hr까지 18.9-22.0 g/100 g oil로 비슷한 함량을 나타내었으나 효소량을 기질 질량의 2, 5, 10%를 사용하였을 경우, 1 hr 이후에도 DAG 함량이 증가하는 경향을 보였다.

• BMB Reports
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• 제50권7호
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• pp.367-372
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• 2017

Monoacylglycerol acyltransferase 1 (MGAT) is a microsomal enzyme that catalyzes the synthesis of diacylglycerol (DAG) and triacylglycerol (TAG). However, the subcellular localization and catalytic function domain of this enzyme is poorly understood. In this report, we identified that murine MGAT1 localizes to the endoplasmic reticulum (ER) under normal conditions, whereas MGAT1 co-localize to the lipid droplets (LD) under conditions of enriching fatty acids, contributing to TAG synthesis and LD expansion. For the enzyme activity, both the N-terminal transmembrane domain and catalytic HPHG motif are required. We also show that the transmembrane domain of MGAT1 consists of two hydrophobic regions in the N-terminus, and the consensus sequence FLXLXXXn, a putative neutral lipid-binding domain, exists in the first transmembrane domain. Finally, MGAT1 interacts with DGAT2, which serves to synergistically increase the TAG biosynthesis and LD expansion, leading to enhancement of lipid accumulation in the liver and fat.

• 약학회지
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• 제41권6호
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• pp.782-788
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• 1997

This study was designed to characterize glucose-enhancing effects on endotoxin-induced prostaglandin production in primary cultured rat vascular smooth muscle cells (VSMC). High glucose treatment significantly augmented prostaglandin (PG) synthesis in lipopolysaccharide (LPS)-stimulated VSMC and this effect was maximal at the concentration of 4mg/ml. It has been reported that increases in glucose metabolism through sorbitol pathway could alter the cytosolic $NADH/NAD^+$ ratio and this change favors de novo synthesis of diacylglycerol (DAG) and, in turn. Results in the activation of protein kinase C (PKC) in vascular tissues. Protein kinase C (PKC) inhibitors, staurosporin and H7, blocked the glucose enhancing effect, and DAG, a PKC activator, significantly increased the PG production stimuated by LPS. Sodium pyruvate, which can reverse the alteration in cytosolic NADH/NAD+ ratio, reduced the high glucose effect on PG production. And also, zopolrestat, a strong aldose reductase inhibitor, almost completely blocked the augmentation effect of glucose on PG synthesis. Arachidonic acid release was significantly increased in high glucose treated group, which implied the increase in $PLA_2$ activity was associated with glucose enhancing effect. Metabloic, labeling study clearly showed that de novo synthesis of prostaglandin H synthase-2 (PGHS-2) is greatly increased in high glucose treated group and this was mitigated by the treatment of zopolrestat. Taken together, the activation of PKC through sorbitol pathway increased the activities of $PLA_2$ and PGHS which resulted in the augmentation in LPS-induced PG production in high glucose treated VSMC.

• Journal of Photoscience
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• 제5권1호
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• pp.1-10
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• 1998

The susceptibility of chilling-resistant spinach plants. and of chilling-sensitive squash plants to photoinhibition was compared in terms of the activity of photosystem II, in relation to the deuce of fatty acid unsaturation of chloroplast membrane lipids. From thylakoid membranes of the plants. monogalactosyl diacylgtycerol, digalactosyl diacylglycerol. sulfoquinovosyt diacylglycerol, and phosphatidylglycerol were seperated as major lipid classes. It was found that the content of cis-unsaturated fatty acids of phosphatidylglycerol was greater by 32% in spinach than that in squash. When leaf disks were exposed to light at 5$\circ$C, 15$\circ$C and 25$\circ$C, photochemical efficiency of photosystem II. measured as the ratio of the variable to the maximum fluorescence of chlorophyll, declined markedly in squash plants, as compared to spinach plants. When leaf disks were exposed to strong light in the presence of lincomycin, an inhibitor of protein synthesis in chloroplasts, photoinhibition was accelerated in the two types of plants. Moreover, lincomycin treatment abolished the differences in the degree of susceptibility to strong light, which had been observed between the two types of plants. When the extent of photoinhibition of photosystem II-mediated electron transport was compared in thylakoid membranes isolated from the two types of plants, there were no differences in the degree of inactivation of photosystem II activity. However, when intact leaf disks were exposed to strong light either at 10$\circ$C or at 25$\circ$C, and then were allowed to recover either at 17$\circ$C or at 25$\circ$C in dim light. chilling-resistant plants such as spinach and pea showed marked recovery from photoinhibition, in contrast to chilling-sensitive plants, such as squash and sweet potato. whose recovery was strongly dependent on the temperature. These findings are discussed in relation to the unsaturation of fatty acids in membrane phosphatidylglycerol. It appears that fatty acid unsaturation of membrane lipids accelerates the recovery of photosystem H from photoinhibition, without affecting the photo-induced inactivation process of photosystem II associated with photoinhibition.