• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.502-510
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• 2009

Although the Escherichia coli heat-labile enterotoxin B subunit (LTB) has already been expressed in several different systems, including prokaryotic and eukaryotic organisms, studies regarding the synthesis of LTB into oligomeric structures of pentameric size in the budding yeast Saccharomyces cerevisiae have been limited. Therefore, this study used a functional signal peptide of the amylase 1A protein from rice to direct the yeast-expressed LTB towards the endoplasmci reticulum to oligomerize with the expected pentameric size. The expression and assembly of the recombinant LTB were confirmed in both the cell-free extract and culture media of the recombinant strain using a Western blot analysis. The binding of the LTB pentamers to intestinal epithelial cell membrane glycolipid receptors was further verified using a GM1-ganglioside enzyme-linked inmmunosorbent assay (GM1-ELISA). On the basis of the GM1-ELISA results, pentameric LTB proteins comprised approximately 0.5-2.0% of the total soluble proteins, and the maximum quantity of secreted LTB was estimated to be 3 mg/l after a 3-day cultivation period. Consequently, the synthesis of LTB monomers and their assembly into biologically active aligomers in a recombinant S. cerevisiae strain demonstrated the feasibility of using a GRAS microorganism-based adjuvant, as well as the development of carriers against mucosal disease.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.153-157
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• 1986

Changes in lipid components of Gae-bul, Urechis unicinctus, during hot-air drying ($40^{\circ}C$, 7 hrs) were studied. Raw sample contained 1.3% total lipid (TL) which consisted of 35.1% neutral lipid (NL), 18.0% glycolipid (GL) and 46.9% phospholipid (PL), and dried sample contained 5.3% TL which consisted of 51.8% NL, 20.5%GL and 27.7% PL. There were about 40% decrease in PL content and a slight increase in NL content during drying. The NL of raw sample mainly consists of triglyceride (TG, 39.8%), free sterol (FS, 39.6%), free fatty acid (FFA, 12.2%). and also identified diglyceride (DG), monoglyceride and esterified sterol and hydrocarbon in less quantify. The percent of TG and FS decreased, while that of FFA and DG increased during drying. And main components in the PL were phosphatidyl choline (PC,45.6%), phosphatidyl ethanolamine (PE,34.8%), and followed by phosphatidyl serine (PS) and an unknown substance. In the components of PL, PE, PS and PC decreased slightly in order during drying. And major fatty acids of raw and dried samples were generally 16:0, 18: 1, 18:3, and 20:5. The content of the polyenoic acid such as 20:5 decreased. while the saturated acid increased slightly during drying.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.506-510
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• 1984

The muscle lipids of cultured and wild eel, Anguilla japonica, were analysed by gas chromatography for fatty acid compositions of total lipid(TL), neutral lipid(NL), phospholipid(PL) and glycolipid(GL). And high performance liquid chromatography(HPLC) patterns of NL were analysed by HPLC. The lipid contents of dorsal muscle of cultured fish are slightly lower than that of wild fish. The contents of TL, NL and PL of wild fish were similar to those of cultured fish, while GL content of wild fish was higher than that of cultured one. In the fatty acid compositions of TL, NL and PL, percentages of $C_{16:0},\;C_{18:1}\;and\;C_{22:6}$ in cultured fish are higher than these in wild one, while percentage of $C_{16:1}$ is lower. Elution patterns in HPLC of NL of wild and cultured eel were slightly different.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.4
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• pp.291-300
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• 1990

The lipid compositions including fatty acid sterol lipid class and the lipid component of the total lipid extracted from the flesh of some fresh water fishes I. e. mandarin cornet cat fish and Korean perch were compared. The levels of total lipid of flesh tissues from the fresh water fishes were high(7.4%) in cat fish but low(1.4-2.2%) in mandarin fish Korean perch and cornet fish. On the contrary the content of unsaponifiable matters found in total lipid was low(2.6%) in cat fish but high(6.0%-6.5%) in mandarin fish Korean perch and cornet fish. Total lipids were mainly composed of triglyceride(74.6-86.5%) as major component in each sample and the other lipid components of total lipid e. g. polar lipid free fatty acids and free sterol were the minor components, The major fatty acids in total lipid of each sample were{{{{ {C }_{16 { }:_{ }0 } }}}}(19.6-29.2%) {{{{ {C }_{16 { }:_{ }1 } }}}}(17.3-30.7%) and {{{{ {C }_{18 { }:_{ }1 } }}}}(16.8-29.2%) and additionally it chiefly consisted of {{{{ {C }_{14 { }:_{ }0 } }}}} and {{{{ {C }_{18 { }:_{ }2 } }}}} Particularly the contents of polyenoic acids in total lipid of cat fish were higher than those of the other fish samples. The level of cholesterol in total lipid was low (8.3mg/g) in cat fish but were high(36.9-59.9mg/g) in mandarin fish Korean perch and cornet fish. The contents of fractionated neutral lipid(NL) were higher than those of polar lipid(PL) in each sample. Particularly phospholipid content in PL was low(6.0%) in cat fish but were high(23.1-36.3%) in mandarin fish Korean perch and cornet fish. Neutral lipids were mainly consisted of triglyceride(84.5-93.4%) as amjor component in each sample and the other lipid components of neutral lipid e, g, free fatty acids and free wterol were exhibited as a minor components, The fatty acid compositon of neutral lipids was very resembled to total lipids. The phospholipid in mandarin cornet and cat-fish were mainly composed of phosphatidyl serine(23.1-49.8%) and phosphatidyl choline(20.8-45.3%) The relatively higher amounts of phosphatidyl serine were observed in mandarine cornet and cat-fist than in Korean perch, But phosphatidyl ethanolamine(42.3%) and phosphatidyl choline (49.9%) were the main phospholipid in Korean perch. The extraordinary high content of phos-phatidyl ethanolamine compared to other fishes was characteristics in phospholipid composition of Korean perch. The major fatty acids in phospholipid of each sample were {{{{ {C }_{16 { }:_{ }0 } }}}} (38.3-46.5%) {{{{ {C}_{18 { }:_{ }0 } }}}}(14.2-21.7) and C16:1(11.6-13.8%) and additionally it chiefly consisted of C18:2, C18:0 and C17:0 The major fatty acids in glycolipid of each sample were C16:0(28.8-40.1%) C18:1(5.4-29.9%) C18:0(5.1-28.9%) and C16:1(8.2-20.1%) and additio-nally it chiefly consisted of C14:0 and C20:1.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.406-412
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• 1984

Total lipids (TL) from Korean pinenut (Pinuskoraiensis S & Z) were extracted, purified and fractionated into three lipid classes (neutral lipid: NL, glycolipid; GL, phospholipid; PL). Lipid contents(constituent components) and fatty acid composition of three lipid classes were determined by thin layer chromatography and gas chromatography. TL ranged from 69.0% to 69.8% in fresh pinenut and consisted of 95.9% to 96.7% NL, 3.2% to2.5% GL and 0.9% to 0.8% PL. In the NL, triglycerides were predominant (80.8%) with the smaller amounts of sterol, diglycerides, free fatty acids, sterol esters and hydrocarbons. Monogalactosyl diglycerides and esterified steryl glycosides (23.5%) were the major components of GL, but cerebrosides, steryl glycosides and digalactosyl diglycerides were also found as minor components. Of the PL, phosphatidyl choline (40.2%) and phosphatidyl ethanolamine (19.4%) were the major components, comprising over 60% of this class. Phosphatidyl inositol, lysophosphatidyl choline were also present in the PL. The major fatty acids in the NL were linoleic acid (48.6%), oleic acid (28.8%) and arachidic acid(14.4%), The fatty acid composition in the GL was similar to the pattern in the NL, but PL contained a higher percentage of palmitic acid (17.7%) and stearic acid (6.0%) than other lipid classes.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.248-252
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• 1985

Prunus tomentosa Thunberg seed was investigated to evaluate its possibility for use as food resources of fats and proteins. The seed contained 40.38% of crude fat and 26.59% of crude protein. The lipid fractions obtained by silicic acid column chromatography were mainly composed of 95.49% of neutral lipids, whereas compound lipids were only 4.51%. Among the neutral lipid components by thin-layer chromatography, triglycerides were 89.86%, sterols, monoglycerides, sterol esters, free fatty acids and diglycerides were 4.14%, 2.98%, 1.77%, 1.07%, and 0.18%, respectively. Oleic acid (65.06-66.05%) and linoleic acid (26.56-28.40%) were the main fatty acids in the total lipid, neutral lipid and triglyceride fractions. In the glycolipid and phospholipid fractions, predominant fatty acids were oleic acid (40.55-51.46%), linoleic acid (20.26-30.89%) and palmitic acid (17.64-21.43%). The extractability of salt soluble protein of seed was 60%, and recovery rate of main protein fraction separated by Sephadex G-200 was about 46.5%. The electrophoretic analysis showed 7 bands in seed protein.

• Korean journal of food and cookery science
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• v.15 no.6
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• pp.645-651
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• 1999

The lipid and fatty acid composition of various poultry eggs were examined after extracting yolk oils from the eggs of caged hen, open barn-reared hen, mallard, and muscovy duck. Total lipid content in 100 g of each edible portion was the highest in muscovy duck egg followed by open barn-reared hen, mallard, caged hen, and natural hen eggs. The triglyceride contents in the egg were in the order of caged hen, open barn-reared hen, natural hen, mallard, and muscovy duck. The cholesterol contents in total lipid were the highest in caged hen and muscovy duck eggs(4.5%), and the lowest in mallard(3.3%). Caged hen eggs had higher neutral lipid ratio among total lipid, but had lower ratio of glycolipid and phospholipid compared with those of the open barn-reared hens. For fatty acid composition, linoleic acid was the highest in the muscovy and linolenic acid was the highest in open barn-reared hen eggs. The contents of arachidonic acid and Eicosapentaenoic acid(EPA) were the highest in muscovy eggs. On the other hand, the content of Docosahexaenoic acid(DHA) was the highest in muscovy duck eggs.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.215-219
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• 1997

As a part of basic investigation for utilizing by-products derived from marine food processing more effectively as a food source, lipid contents, fatty acid compositions and lipid compositions in viscera and head of conger eel and hair tail, viscera of mackerel pike, and squids caught off Newzealand and off Falkland island were determined. The lipid contents in marine by-products showed $40.5{\sim}48.0%$ on a dry weight basis and it consisted of $92.1{\sim}99.0%$ neutral lipid and $1.0{\sim}7.9%$ polar lipid such as phospholipid and glycolipid. The neutral lipids mainly consisted of triglyceride$(50.0{\sim}69.9%)$ and had free fatty acid, free sterol, esterified sterol and hydrocarbon, diglyceride, and monoglyceride in less quantity. Squid viscera oil showed higher content in polyenes such as 20:5 and 22:6 than by-product oil derived from fish processing. Viscera oil of squid caught off Newzealand(21.1%) was the highest on DHA composition, followed by that of squid caught off Falkland island(16.3%), hair tail by-product oil(13.9%), conger eel by-product oil(11.7%) and mackerel pike by-product oil(10.7%), in the order named. The major fatty acids in total lipid and neutral lipid of byproducts were generally 16:0, 18: 1n-9, 20:5n-3 and 22:6n-3.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.381-385
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• 2010

Five types of determination methods including the Soxhlet method as well as 3 kinds of extraction solvents, were used for the determination of accurate crude fat contents in wheat flour and 5 kinds of dry noodles. According to the results, crude fat contents were 0.09~1.37% in the wheat flour and 0.07~1.36% in the dry noodle samples. This variation resulted from the types of lipids in the wheat flour and various kinds of dry noodles. Nutrition facts labels showing crude fat contents in the 5 kinds of domestic dry noodle samples indicated levels of 0~1.5%. Lipid composition and content were determined in order to investigate these differences. The results indicated free lipid at 1.02% and bound lipids at 0.21% in the wheat flour, and free lipids at 0.95~1.01% and bound lipid at 0.21~0.25% in the wheat flour. Polar and nonpolar lipid contents were also measured in all samples. Neutral lipid, glycolipid and phospholipid contents in the free lipid were 58.5%, 33.6%, and 8.6% in the wheat flour, and 49.2~58.2%, 33.3~41.6%, and 8.5~9.3% in the dry noodle samples, respectively. For bound lipids, amounts were 16.7%, 33.5%, and 49.5% in the wheat flour, and 13.2~15.3%, 35.6~45.7%, and 41.6~49.4% in the dry noodle samples, respectively. Based on these results, an acid hydrolysis methods should be used to determine accurate crude fat contents in wheat flour and dry noodles.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.652-657
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• 1995

To investigate the lipid components of Korean yams(Dioscorea batatas and Dioscorea aimadoimo), silicic acid column, thin layer and gas chromatographies were applied. Total crude lipid contents in D. batatas and D. aimadoimo were 1.70% and 1.31%, and total purified lipid contents were 1.35% and 0.99% on a dry weight basis. Lipids were fractionated and quantitated by silicic acid column chromatography. The contents of neutral lipids, glycolipids and phospholipids were 43.33, 39.60 and 17.07% in D. batatas and 43.94, 34.74 and 21.32% in D. aimadoimo. Neutral lipids were the most abundant, in which triglycerides and sterol ester were found as the major components. Glycolipids were mainly composed of monogalactosyl and trigalactosyl diglycerides. Phosphatidyl choline and phosphatidyl ethanolamine were the major components of phospholipid. Fatty acids of the total lipids were mainly linoleic and palmitic acids. The fatty acid compositions of neutral lipids, glycolipids and phospholipids were the same tendency as that of total lipids. However, the content of linolenic acid in glycolipids was higher than in neutral lipids and phospholipids when fractionated.