• Journal of the Korean Wood Science and Technology
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• v.34 no.5
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• pp.104-110
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• 2006

We investigated why aspen extractives are more resistant in kraft pulping than pine extractives. Residual extractives content in aspen kraft pulps were 0.5~1.1% compared with 0.1~0.2% in pine pulps. This different response arises from the different composition of extractives in wood chips. Resin acids in pine were almost completely removed in kraft pulping but those are not existence in aspen. Slower saponification of aspen steryl esters resulted from different chemical structure of aspen steryl esters. Main sterols in aspen steryl esters were 24-methyl cyclolanostenol which was highly resistant to alkaline hydrolysis with its characteristic steric hindrance. Sterols in aspen were not well removed in kraft pulping. The relative composition of sterol in aspen kraft pulps was increased with increasing pulping time. The presence of fatty acids in aspen kraft pulps is considered to unusual. Fatty acids in alkaline are supposed to be well ionized and removed well in the washing stage. Nevertheless, there were significant amount of fatty acids remaining in aspen kraft pulps.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.74-80
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• 2005

The compositions of residual extractives in woodmeal, unbleached and oxygen-delignified aspen kraft pulps were investigated with gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS) with focus on fate of extractives in kraft pulping and oxygen delignification. Steryl esters and shorter retention time (shorter than palmitic acid) extractives were main extractives in aspen woodmeal. Shorter retention time extractives were well removed in kraft pulping. Sterol esters were hydrolyzed to sterols and fatty acids. Sterols and fatty acids were two major extractives classes in unbleached kraft pulps. Linoleic acid was main fatty acids in unbleached pulps compared with palmitic acid which is generally found in aspen woodmeal. Sterolsand fatty acids were also two major extractives classes in oxygen-delignified kraft pulps. However, linoleic acid was well removed in oxygen delignification.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.104.2-105
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• 2003

Plant steryl esters have good effects on plasma cholesterol level and are used as functional food ingredient. Conjugated linoleic acid (CLA) presents mainly in animal foods and has a good benefit and medium chain fatty acids (MCFAs) are a rapid energy source for human. In this study, we produced the ${\beta}$-sitosterol esters from CLA and MCFAs using various lipases as catalysts. Among lipases, AYS (from Candida rugosa) was the most effective for synthesis of ${\beta}$-sitosterol esters in the presence of water (24.35% conversion) or hexane (25.33% conversion). The second esterification extent was obtained by lipase AK (from Pseudomonas sp), showing 10.26% conversion in water and 15.94% conversion in hexane, respectively. The reaction condition was 1:3 molar ratio (${\beta}$-sitosterol:fatty acid, 1:3) and stirred (175 rpm) at 55$^{\circ}C$ in water bath shaker for 48h.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.262-268
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• 1988

Total lipids of Korean black Soybean were extracted, purified and fractionated into three lipid classes (Neutral lipid, NL; glycolipid, GL;phospholipid, PL) and the composition of lipid class and fatty acid were studied. Total lipids of black soybean consisted of 88.5% NL, 2.5% GL and-9.0% PL. In the NL, triglycerides were predominant(80.4%) and also sterol esters, hydrocarbons, diglycerides, free fatty acids and sterols were identified. The major component of GL were monogalactosyl diglycerides and esterified steryl glycosides, and then cerebrosides, steryl glycosides, digalactosyl diglycerides were also found. As major component of the PL, phosphatidyl ethanolamine and phosphatidyl choline were observed, other compounds such as phosphatidyl inositol, phosphatidyl serine and lysophosphatidyl choline were also determined. The major fatty acids in the NL and GL were linoleic acid, oleic acid and palmitic acid, however, PL contained higher relative content of palmitic acid and lower level of oleic acid compared with those of NL and GL.

• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.195-201
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• 1983

Lipids isolated from three barley samples were identified and quantitated by column, thin layer and gas liquid chromatographic techniques. These lipids were shown to consist of 69.3-73.1% neutral lipids, 9.6-16.5% glycolipids, and 14.2-17.9% phospholipids. Among the neutral lipids, triglycerides were predominant (54.2 to 55.7%) with smaller amounts of 1,2-diglycerides, 1,3-diglycerides, free sterols, free fatty acids, steryl esters, and three unknown being present. Among the glycolipids, digalactosyl diglycerides (31.3 to 33.2%) and monogalactosyl diglycerides (26.2 to 29.6%) were the most abundant. Esterified steryl glycosides, steryl glycosides, cerebrosides, sulfolipids, and an unknown component were present as minor components. Of the phosopholipids, phosphatidyl cholines and serines, lysophosphatidyl cholines, and phosphatidyl ethanolamines were the major components, comprising over 80% of this class. The major fatty acids in the total and the three lipid classes were palmitic, oleic, linoleic and linolenic acids. However, the neutral lipids fraction contained more oleic acid than other lipid fractions, and the phospholipids fraction contained more palmitic acid than the other lipid fractions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.175-180
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• 1984

Lipids in oyster mushroom (Pleurotus florida) were extracted by the mixture of chloroform-methanol (2: 1, v/v) and fractionated into neutral lipids, glycolipids and phospholipids by silicic acid column chromatography. Components and fatty acid composition of each fraction were deter- mined by thin-layer and gas-liquid chromatographies. Fresh oyster mushroom contained 0.5% total lipid in which the contents if neutral lipids, glycolipids and phospholipids were 33.8%, 19.7% and 45. 6%, respectively, Triglycerides(38.2%), free fatty acids (20%) and free sterol (10%) were the major components among the neutral lipids. Diglycerides, monoglycerides, sterol esters and three unidentified neutral lipids were the minor components. Major components of glycolipids were steryl glycosides(35.9%) and esterified steryl glycosides (23.7%). Digalactosyl diglycerides, mono-galactosyl diglycerides and two unknown components were also present. Of the phospholipids, phosphatidyl cholines and serines (48.2%), and phosphatidyl ethanolamines(44.4%) were the major components. On the other hand, the major fatty acids of neutral lipids we.e linoleic, palmitoleic, oleic and palmitic acid. Linoleic and palmitic acid were the predominant fatty acids of both glycolipids and phospholipids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.29-35
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• 1992

Total lipids of Korean black soybean (Glycine man Merr) during soaking in water were extracted, purified and fractionated into three lipid classes, and then lipid contents and their fatty acid compositions were investigated. The lipids of the beans consisted of 89.1% neutral lipids, 1.5% glycolipids and 9.4% phospholipids, and these fractions did not change significantly during the soaking period. The neutral lipid fraction of the beans contained 92.1% triglyceride, 3.0% sterol esters and hydrocarbons, 2.8% diglyceride, 1.5% free fatty acids, 0.3% free sterols and 0.3% monoglyceride, and no significant changes were found in the composition of neutral lipid fraction from the soaked beans. Major components of the glycolipid fraction were esterified steryl glycosides (43.6%), steryl glycosides (26.6%) and digalactosyl diglycerides (14.5%), and these fractions did not change significantly during the soaking period. On the other hand, phosphatidyl choline (41.6%) and phosphatidyl ethanolamine (39.5%) were most abundant components found in the phospholipid fraction, and the contents of phospholipids changed a little during the soaking period. Linoleic acid, oleic acid and palmitic acid were the major fatty acids found in total lipids, neutral lipids, glycolipids and phospholipids. A few changes in the major fatty acid compositions of phospholipids were observed during the soaking period.

• Journal of the Korean Society of Food Culture
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• v.7 no.4
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• pp.303-307
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• 1992

The lipid compositions of buckwheats produced in Korea were analyzed. The samples used in this experiment were as follows; Kyungbuk rice buckwheat. Kangwon hull buckwheat and Kangwon rice buckwheat. The total lipids were extracted and fractionated to neutral lipids, glycolipids and phospholipids respectively by silicic acid column chromatography (SACC). As a result, neutral lipids content of these three samples were in the range of 82.77-95.65%; glycolipids in 1.97-10.83%; and phospholipids in 2.21-6.40%. The composition of neutral lipids of these three samples showed that triglyceride were in the range of 88.7-92.0%; monoglyceride in 2.3-4.0%; free fatty acid in 3.0-3.7%; diglyceride in 0.7-0.8%.; free sterol in 0-0.7%; and steryl esters in 0-2.2%. The major fatty acids of total lipid, neutral lipid, glycolipids and phospholipids of these three samples were oleic, linoleic and palmitic acids.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.137-142
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• 1986

The lipids content and neutral lipid component of milled rice grain were studied for four nonglutionous and two glutinous varieties grown in Korea. The average total lipid contents in nonglutinous and glutinous varieties were 0.94% and 1.78% by dry weight basis, respectively. The ratios of neutral lipid, glycolipid and phospholipid in the total lipid were 76.5 : 14.8 : 8.6 in the nonglutionous and 82.4 : 11.1 : 6.5 in the glutinous, respectively. Main classes of the neutral lipids were triglycerides, free fatty acids, steryl esters, free sterols, monoglycerids and diglycerides in both of nonglutinous and glutinous, and no significance was observed in the content of the classes between both varieties. The major fatty acid composition of total and neutral lipids were linoleic, oleic and palmitic acids in both of nonglutinous and glutinous varieties.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.585-593
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• 1988

The lipid contents and neutral lipid components of brown rice, milled rice and bran were studied for four varieties of rice such as Nampung, Milyang #23, Whasung and Jinhung. Total lipid contents of brown rice, milled rice and bran were 2.65%, 1.09% and 20.24% respectively. The ratios of neutral lipids, glycolipids and phospholipids in total lipids were 82.53:12.39:4.08 in brown rice and 87.72:7.02:5.26 in bran. Neutral lipids were separated on the TLC; among them 6 neutral lipids were identified by comparing the RF value of standards. Triglycerides(TG), free fatty acids(FFA) and steryl esters(SE) were major neutral lipid components in brown rice, milled rice and bran. TG content of the bran, compared to that of brown rice and milled rice, was very low in contrast the FFA content was high. The major fatty acids of total lipid and neutral lipid fractions were palmitic, linoleic and oleic acids, comprising over 95% of these classes.