• 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.

• KSBB Journal
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• v.14 no.3
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• pp.259-263
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• 1999

Fish oil was hydrolyzed with Aspergillus oryzae lipase, Lipolase-100T. The hydrolysis characteristics of Lipolsae-100T were investigated. Lipolase-100T showed 1,3-positional specificity which hydrolyzed acyl chains combined on the 1 or 3 position of triglyceride into free fatty acids. Lipolase-100T represented another property that the saturated fatty acids composing the triglyceride were hydrolyzed more easily that the polyunsaturated fatty acids(PUFAs). n-3 PUFAs, such as C16:4, C20:5 and C22:6, were hardly hydrolyzed, so that the concentrations of those in the mixture of glycerides were increased according to hydrolysis time. Especially docosahexaenoic acid(DHA), C22:6 showed the highest increase in the concentration. This result explained that n-3 PUFAs were combined on 2-position of triglyceride. When the hydrolysis of fish oil with Lipolase-100T 0.4 wt% was performed for 120 hr, n-3 PUFAs wt% was increased to 50 wt% in the mixture of glycerides. This result was obtained due to the 1,3-positional specificity of Lipolase-100T and positional specificity of n-3 PUFAs.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1541-1544
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• 2009

This study evaluated effects of enzymatic hydrolysates of squid on cholesterol lowering in rats. Thirty male rats were blocked into 3 groups [high cholesterol diet (control), 5% normal squid, and 5% enzymatic hydrolysates of squid] and were raised for 10 weeks. Triglyceride level in enzymatic hydrolysates of squid-fed rats was lower than that in the control. Serum low density lipoprotein-cholesterol level followed in the order of control>normal squid>enzymatic hydrolysates. Serum high density lipoprotein-cholesterol level in enzymatic hydrolysates of squid-fed rats was higher than that in control rats. Liver cholesterol level in enzymatic hydrolysates of squid-fed rats was lower than that in control rats.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.134-139
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• 1987

The triglycerides of walnut oil were fractionated by high performance liquid chromatography (HPLC) on the basis of partition number (PN). Each triglyceride was finally fractionated on the basis of aryl carbon numbers (CN) by gas-liquid chromatography (GLC). The fatty acids of triglyceride for each PN group were analyzed by GLC. Also, the fatty acid at ${\beta}-position$ of glycerol in each PN fraction separated by HPLC was determined by enzymatic hydrolysis with pancreatic lipase. The major triglyceride molecular species of walnut oil were $C_{18:2}{\cdot}C_{18:2}{\cdot}C_{18:1}$(LLO; 10.9%), $C_{18:3}{\cdot}C_{18:2}{\cdot}C_{18:2}$(LnLL; 17.6%) and $C_{18:2}{\cdot}C_{18:2}{\cdot}C_{18:2}$(LLL; 37.3%). The triglyceride molecular species occupied by unsaturated fatty acid at ${\beta}-position$ were more than 90%.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.122-128
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• 1987

Lipases from Candida rogosa and Rhizopus arrhizus were immobilized by entrapment with photo-crosslinkable resin prepolymer for the study of fat splitting and interesterification in isooctane-two phase system. Dioctylsulfosuccinate was selected as the most suitable surfactant during the immobilization. Lipase entrapped with hydrophobic photo-crosslinkable resin prepolymer(ENTP-3000) exhibited the highest activity, whereas lipase entrapped with hydrophilic gel(ENT-4000) was more stable in organic solvent. As the degree of hydrophobicity of the immobilization matrix was increased, Vm(app) of the lipase entrapped was increased, but Km(app) was approximately constant. While the optimum pH of the lipases entrapped on hydrophilic gel (ENT-4000) were around pH 7.0 for Candida lipase and Rhizopus lipase, the reaction rate of the lipases entrapped on hydrophobic gel were less dependent on pH variations for short reaction time. However, for longer reaction time, the lipnses from C. rugosa and R. arrhizus entrapped on hydrophobic gel yielded maximum rate at pH 6.0 and 6.5, respectively, Entrapment method endowed the lipase with thermal stability.

• Journal of Animal Science and Technology
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• v.55 no.4
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• pp.303-314
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• 2013

Knowledge regarding lipid catabolism has been of great interest in the field of animal sciences. In the livestock industry, excess fat accretion in meat is costly to the producer and undesirable to the consumer. However, intramuscular fat (marbling) is desirable to enhance carcass and product quality. The manipulation of lipid content to meet the goals of animal production requires an understanding of the detailed mechanisms of lipid catabolism to help meticulously design nutritional, pharmacological, and physiological approaches to regulate fat accretion. The concept of a basic system of lipases and their co-regulators has been identified. The major lipases cleave triacylglycerol (TAG) stored in lipid droplets in a sequential manner. In adipose tissue, adipose triglyceride lipase (ATGL) performs the first and rate-limiting step of TAG breakdown through hydrolysis at the sn-1 position of TAG to release a non-esterified fatty acid (NEFA) and diacylglycerol (DAG). Subsequently, cleavage of DAG occurs via the rate-limiting enzyme hormone-sensitive lipase (HSL) for DAG catabolism, which is followed by monoglyceride lipase (MGL) for monoacylglycerol (MAG) hydrolysis. Recent identification of the co-activator (Comparative Gene Identification-58) and inhibitor [G(0)/G(1) Switch Gene 2] of ATGL have helped elucidate this important initial step of TAG breakdown, while also generating more questions. Additionally, the roles of these lipolysis-related enzymes in muscle, liver and skin tissue have also been found to be of great importance for the investigation of systemic lipolytic regulation.

• Journal of Environmental Science International
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• v.19 no.10
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• pp.1247-1256
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• 2010

Since biodiesel as bioenergy is defined as ester compounds formed by esterification of animal/vegetable oils, in this study three vegetable cooking oils (market, waste and refined waste ones) were esterified by reactions of alkali catalyst and immobilized enzyme. The fatty acid composition of the formed ester compounds was analyzed to investigate the feasibility of biodiesel production. By lipolysis (i.e, hydrolysis of Triglyceride (TG)), all three vegetable oils used in this study were found to produce Diglyceride (DG), Monoglyceride (MD) and Fatty acid ethylester (FAEE). However, the amount of produced FAEE (which can be used as an energy source) was in the increasing order of market cooking oil, waste one and refined waste one. With NaOH catalyst, FAEE was produced about 24.92, 17.63 and 11.31 % for the respective oils while adding Lipozyme TL produced FAEE about 43.54, 38.16 and 24.47 %, respectively. This indicates that enzyme catalyst is more effective than alkali one for transesterification. In addition, it was found that the composition of fatty acids produced by hydrolysis of TG was unchanged with alkali and immobilized enzyme reactions. Thus it can be expected that stable conditions remain in the course of mixing with gasoline whose composition is similar to that of the fatty acids.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.91-97
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• 1987

Because of its more complete hydrolysis and rapid absorption, MCT is expected its usefulness in the diets of patients with malabsorption syndrom. Also, several authors reported that serum cholesterol level was lower after MCT feedings. In this study, rate of each experimental group were fed for 4weeks with 20％ MCT, 20％ corn oil, mixed diet of 10％ MCT and 10％ corn oil, mixed diet of 17％ corn oil and 3％ shortening. After experimental diet, it was measured to growth rate and serum cholesterol, triglyceride and phospholipid level. The results were as follows; 1. The body weight gain was the lowest in MCT group and others were lower than control group. 2. Serum total cholesterol level was the lowest in corn oil group and others were significantly lower than control group. Free cholesterol level was lower in all experimental groups than control group too. 3. Serum HDL-cholesterol level was significantly higher in all experimental groups than control group. 4. The ratio of VLDL, LDL-Cholesterol to HDL-Cholesterol was significantly lower in all experimental groups than control group. 5. Serum triglyceride level was higher in all experimental groups than control group. Serum phospholipid level was significantly in only mixed diet group of corn oil and shortening than control group. 6. The ratio of total cholesterol to phospholipid was significantly lower in corn oil diet group than control group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.399-408
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• 1998

The effect of low molecular alginates feeding on the cholesterol levels and fatty acid compositions of rat serum and liver lipid were investigated. After one week basal diet feeding, four week old Sprague-Dawley male rats were fed with water soluble and acid $\cdot$alkali soluble alginate extracted from sea mustard (Undaria pinnatifida) and giant kelp (Macrocystis pyrifera), and their low molecular alginates prepared by the HCl partial hydrolysis. The feeding efficiency of the alginate fed group was ranged in 0.37$\~$0.44, which was 0.03$\~$0.05 lower than that of the basal diet group. Also, there was much less increase of liver weight in the alginate fed group. The water soluble alginate showed more significant effect in reducing the total cholesterol, free cholesterol, LDL-cholesterol, triglyceride and phospholipid of serum and liver lipid than the acid$\cdot$alkali soluble alginate. The effect was much better with low molecular alginate (reducing effect by the low-molecularization : Water soluble alginate - serum lipid; total cholesterol $59\%$, free cholesterol $65\%$, LDL-cholesterol $96\%$, triglyceride $50\%$, and phospholipid $36\%$. liver lipid: total cholesterol $4\%$, free cholesterol $62\%$, LDL-cholesterol $44\%$, triglyceride $33\%$, and phospholipid $44\%$. acid$\cdot$alkali soluble alginate - serum lipid; total cholesterol $52\%$: free cholesterol $97\%$, LDL-cholesterol $78\%$ triglyceride $32\%$, and phospholipid $64\%$. liver lipid; total cholesterol $11\%$, free cholesterol $12\%$, LDL-cholesterol $10\%$, triglyceride $27\%$, and phospholipid $21\%$). The effect of low molecular alginate feeding on the fatty acid composition of serum and liver lipid reflects the remarkable increase of polyenoic acid, over $44\%$ in serum lipid and about $70\%$ in liver lipid, comparing to the cholesterol fed group. The overall results indicated that feeding of low molecular alginates improves physiological function of rats by changing the serum and liver lipid composition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.355-361
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• 1995

Lipoprotein lipase(LPL) is an acylglycerol hydrolase and is the extrahepatic enzyme responsible for the hydrolysis of triglyceride-rich plasma lipoproteins. LPL has been isolated from bovine milk by affinity chromatography on heparin-sepharose in 2M NaCl, 5mM barbital buffer, pH 7.4. Para-nitrophenyl butyrate(PNPB) was used as a substrate for the determination of LPL activity. Molecular weight of LPL was 55KD on 10% SDS-PAGE. When the effects of heparin on LPL activation were compared, LPL activity of heparin added group increased approximately 5 times higher than that of heparin non-added groups. These results indicated that heparin involved in the stabilization of LPL structure that led to increase enzyme activity. Furthermore, LPL activity increased about 4 times compared to the absence of heparin at various pH. LPL was stabilized when heparin was added either low or high salt concentrations. With the presence of heparin, NaCl concentration did not affect LPL activity at pH range 6∼9.