• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.624-630
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• 1999

In order to investigate the position of various fatty acids attached to glycerol and the specificity of Lipolase-100T, hydrolysis of fish oil was carried out with Lipolase-100T derived from Aspergillus oryzae. The amounts of free fatty acids produced from triglyceride, 1,2(2,3)-diglyceride, 1,3-diglyceride, and 2-monoglyceride and conversion rates of 1,2(2,3)-diglyceride to 1,3-diglyceride and 2-monoglyceride to 1(3)-monoglyceride were also calculated. The ratio of 1,2-diglyceride content to 1,3-diglyceride was higher than 70 in the early period of hydrolysis. The fatty acid content of the glyceride mixture after 72 h of hydrolysis was compared with that of fish oil, and it was found that polyunsaturated fatty acids such as C16:4, C20:4 n-3, C20:5 n-3, C21:5 n-3, C22:5 n-3 and C22:6 n-3 were located in the 2-position of glycerol. Material balance of each component in the hydrolysis system was written to obtain a set of simultaneous linear equations. The theoretical quantity of free fatty acids produced from triglyceride, 1,2-diglyceride, 1,3-diglyceride, and monoglyceride, respectively, were calculated by solving the linear equation system. The conversion rate of 1,2(2,3)-diglyceride to 1,3-diglyceride and that of 2-monoglyceride to 1(3)-monoglyceride were also obtained. The results showed that the migration rate of 1,2(2,3)-diglyceride to 1,3-diglyceride was higher than the hydrolysis rate of 1,2(2,3)-diglyceride to 2-monoglyceride and the conversion rate of 2-monoglyceride to 1(3)-monoglyceride was extremely low.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.304-313
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• 1979

The compositions of the polar lipids in the free and bound lipids from four varieties of experimentally cultivated potatoes were identified and quantified by thin layer- and gas-liquid chromatographies. The results were summarized as follows : 1. The glycolipids contained in the free and bound lipids were fractionated and identified as esterified sterol glycoside, monogalactosyl diglyceride, sterol glycoside, digalactosyl diglyceride, and trigalactosyl diglyceride, of which the highest content to the total lipid quantity were 5.8% of esterified sterol glycoside in the free lipid and 6.1% of trigalactosyl diglyceride in the bound lipid. The content of monogalactosyl diglyceride in the free and bound lipids was almost the same, whereas the content of esterified sterol glycoside was higher in the free lipid than in the bound lipid, and the contents of sterol glycoside, digalactosyl diglyceride, and trigalactosyl diglyceride were higher in the bound lipid than in the free lipid on the contrary. 2. The phospholipid contained in the free and bound lipids were fractionated and identified as phosphatidyl ethanolamine, phosphatidyl glyceride, phosphatidyl choline, and phosphatidyl inositol, but the phosphatidyl glyceride was not detected in the free lipid. The highest content in the total lipid quantity was 3.3 % of phosophatidyl choline in the case of the free lipid, while 14.9 % of the phosphatidyl ethanolamine contained in the bound lipid was the highest. All other constituents of phospholipid were contained in larger quantity in the bound lipid than in the free lipid. 3. The fatty acid composition of glycolipid in the free and bound lipids was also the same as that of the total free and bound lipids. The differences were that the content of palmitic acid was higher in the glycolipid of the free lipid than in the total free lipid and the content of linoleic acid was lower in the glycolipid.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.119-126
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• 1991

The lipid fractions, lipid classes and free fatty acids in total lipids from cheese and soybeans were analyzed by column, thin-layer and gas chromatographies. The percentages of neutral lipid, glycolipid and phospholipid in cheese were 96.2, 1.1 and 0.7, whereas those in soybeans were 87.5, 0.5 and 4.3. Major lipid classes of total lipid, and neutral lipid were triglyceride, fatty acid, cholesterol, diglyceride, monoglyceride and polar lipid, and those of glycolipid and phospholipid were triglyceride, diglyceride, monoglyceride and polar lipid in total lipid from cheese. Large amounts of triglyceride and polar lipid and small amounts of diglyceride, monoglyceride and polar lipid were detected in all lipid fractions from soybeans. The higher proportion of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C16:1, C18:0, C18:1 and C18:2 fatty acids were found in total lipid from cheese, whereas those of C18:0, C18:2 and C18:3 fatty acids were found in total lipid from soybeans. Most predominant fatty acids are C16:0 for the total lipid of cheese and C18:2 for the total lipid of soybeans. The lower proportions of C14:1, C15:0, C17:0 and C20:0 fatty acids in total lipid from cheese and C4:0, C6:0, C10:0 and C18:0 in total lipid from soybeans were detected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.735-740
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• 1996

This study was carried out to determine the composition of glycolipids and phospholipids in Japonica and Indica rice bran oils. The ratio of glycolipids and phospholipids was 4.1 : 6.5% in Japonica rice bran oils and 2.6 : 3.7% in Indica rice bran oils. Polar lipid content was significantly higher in Japonica rice bran oils. The main components of glycolipids were esterified steryl glycoside, monogalactosyl diglyceride steryl glycoside, cerebroside and digalactosyl diglyceride. The content of esterified steryl glycoside was the highest, resulting in 48.8~52.1% of total glycolipids. Phospholipids in rice bran oils consisted of diphosphatidyl glycerol, phosphatidyl ethanolamines, phosphatidyl inositol, phosphatidyl serines, phosphatidyl choline and lysophosphotidyl choline. Major fatty acids of the glycolipids and phospholipids fractions were oleic, linoleic and palmitic acids in Japonica and Indica rice bran oils.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.192-197
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• 1999

The contents of total lipids and their components of brown rice grain were studied for 5 colored rice cultivars, 1 aromatic rice cultivar and 1 normal rice cultivar grown in Korea. The total lipid contents ranged 2.04 to 4.69% based on total dry weight. The Tohoku #149 showed the highest content which was followed by Hansanheukmi and Sanghaehyang-hyeolna. The lowest content were observed in three cultivars, Heuknambyeo, Hyangnambyo and Dongjinbyeo which showed no difference among cultivars. The main classes of the total lipid were triglyceride, diglyceride, free sterol, free fatty acid and sterol esters in all cultivars examined. The ratio of triglyceride in total lipid was high in colored rice and aromatic rice compared to Dongjinbyeo which is normal rice cultivars, but the ratio of diglyceride was high in Dongjinbyeo. The major fatty acid compositions in the cultivars examined were linoleic acid, oleic acid and palmitic acid. There was a varietal difference in fatty acid composition, for example, erucic acid was detected in aromatic and colored rices cultivars, while none of this compound was found in Dongjinbyeo.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.145-150
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• 2007

Conjugated linoleic acid (CLA) reduces fat deposition in several mammalian species. The proposed mechanisms for this effect are reduced preadipocyte proliferation and differentiation. The objective of this study was to investigate the inhibitory effects of diglyceride (DG), CLA, DG-CLA of proliferation and differentiation of 3T3-L1 preadipocytes. Cell viability was determined using WST-8 analysis and cell differentiation was determined by glycerol-3-phosphate dehydrogenase (GPDH) activity. Lipid accumulation in differentiating 3T3-L1 cells was measured by Oil red O staining. The proliferation of preconfluent 3T3-L1 cells by treatments of DG, CLA, and DG-CLA was reduced in a dose-dependent manner. CLA among them was the most effective in reduction of viable cells with increasing concentrations. Treatments of the DG, CLA, and DG-CLA at the concentration of $100{\cdot}\ddot{I}g/ml$ for 48h significantly inhibited differentiation of 3T3-L1 cells (p<0.05). In addition. cytoplasmic lipid accumulation during differentiation of the 3T3-L1 preadipocytes was also inhibited by treatments of the test solutions. DG-CLA was the most effective in the inhibition of differentiation and lipid accumulation in 3T3-L1 cells. These results indicate that the DG including CLA as fatty acids is more effective for anti-obesity than DG or CLA alone and that consumption of DG-CLA as a dietary oil may give a benefit for controlling overweight in humans.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.509-515
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• 1994

Using the lipids extracted from Korean yam(Dioscorea) tubers, D. batatas, D. aimadoimo and D. japonica, fractionation and identification of lipid components and their fatty acid compositions were analysed. Lipid contents determined by Folch's method in D. batatas, D. aimadoimo and D. japonica were 11.0 mg/g, 11.4 mg/g and 6.6 mg/g, respectively. Lipids extracted were fractionated into neutral lipid, glycolipid and phospholipid by silicic acid column chromatography. The content of neutral lipid was over about 60% in lipid. Neutral lipid was composed of sterol ester, triglyceride, 1,3-diglyceride, 1,2-diglyceride and monoglyceride. Main constituents of glycolipid were acylsterylglycoside, monogalactosyldiglyceride, sterylglycoside, digalactosyldiglyceride and sulfolipid, and phospholipid contained phosphatidylethanolamine, phosphatidylcholine and phosphatidylinositol. The fatty acids of the total lipid and its three lipid fractions were analyzed by GC. The major fatty acids were palmitic and linoleic acids. Content of the saturated fatty acids was less than that of the unsaturated fatty acids.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.437-445
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• 1997

Studies were carried out to investigate the changes of lipids in chestnut (Castanea crenata Sieb. et Zucc) during storage at $20^{\circ}C$ for 9 weeks and $1^{\circ}C$ for 15 weeks. Lipid composition of fresh chestnuts were 43.4% of nonpolar lipid (NPL), 26.5% of glycolipid (GL) and 30.1% of phospholipid (PL) in total lipid (TL). Nonpolar lipid was composed of triglyceride (TG), 1,2-diglyceride (1,2-DG), 1,3-diglyceride (1,3-DG), sterolester (SE), sterol (S) and free fatty acid (FFA). Main constituents of glycolipid were digalactosyldiglyceride (DGDG), monogalactosyldiglyceride (MGDG), sterylglycoside (SG), and acylsteryglycoside (ASG). Main constituents of phospholipid were phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI). The content of nonpolar lipid was decreased after 5 weeks of storage, and glycolipid content was increased during 7 weeks and then decreased. Phospholipid was the most increased lipid during storage at $20^{\circ}C$ and $1^{\circ}C$. The contents of TG, SE, S, DGDG and MGDG were increased during storage at $20^{\circ}C$ and $1^{\circ}C$. The major fatty acids were linoleic acid, oleic acid, palmitic acid and linolenic acid in TL, NPL, GL, PL, TG, DG, ASG, PC and PE. The content of palmitic acid was relatively higher in the PL. Linoleic acid among them was increased during storage at $20^{\circ}C$ and $1^{\circ}C$, while oleic acid was decreased.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.452-456
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• 2010

It is known that 1,3-diglyceride (1,3-DG) hardly accumulates inside human body because the metabolism of 1,3-DG is entirely different from that of general fats such as triglycerides (TG). This research focuses on the selective synthesis of 1,3-DG by the esterification reaction using an immobilized lipase. For a reaction between glycerin and oleic acid (OA) with a mole ratio of 1 : 2 under vacuum, changes in the compositions of monoglyceride (MG), TG and DG and the contents of 1,3-isomers in DG were investigated, as a function of reaction temperature and the amount of lipase. The reactivities determined by the rate of the consumption of OA became higher with the increase in temperature and the amount of lipase. When the results were compared with those obtained in the earlier study where Novozym was applied as an immobilized lipase, the reactivity was higher for Novozym, on the other hand, selectivity to 1,3-DG was much higher for Lipozyme. Especially, it is remarkable that 1,3-DG content in total DG reached to 98% in the reaction carried out at $50^{\circ}C$ using Lipozyme.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.443-448
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• 2009

It is known that 1,3-diglyceride (1,3-DG) hardly accumulates inside human body because the metabolism of 1,3-DG is entirely different from that of general fats such as triglycerides (TG). This research focuses on the selective synthesis of 1,3-DG by the esterification reaction using an immobilized lipase. For a reaction between glycerin and oleic acid (OA) with a mole ratio of 1 : 2 under vacuum, changes in the compositions of monoglyceride (MG), TG and DG and the contents of 1,3-isomers in DG were investigated, as a function of reaction temperature and the amount of lipase. The reactivities determined by the rate of the consumption of OA became higher with increased in temperature and the amount of lipase. Changes in the compositions of MG, DG and TG, however, occurred after the DG content reached maximum, which were found to be dependent on various factors. TG was a main product, and significant decrease in the amount of both 1,3-DG and DG were observed, when reactions were carried out at high temperatures or when 10 wt% of lipase was used.