• Food Science and Biotechnology
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• v.14 no.6
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• pp.727-731
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• 2005

Synthesized Ile-Ala-Val-Pro (IAVP) peptide, which has the highest hypocholesterolemic effect among a number of synthesized derivatives of Ile-Ala-Val-Pro-Gly-Glu-Val-Ala (IAVPGEVA) isolated from 11S globulin of soy protein by pepsin digestion, was selected for investigation in the present study. Using a recombinant Syrian hamster 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), we studied in detail the inhibition of this enzyme by IAVP and compared the action of this peptide to that of lovastatin, a known competitive inhibitor of this enzyme. The concentration of IAVP required for 50% inhibition ($IC_{50}$) of HMGR activity in given experimental conditions was $340\;{\mu}M$. Kinetic analysis revealed that the studied peptide is a competitive inhibitor of HMGR with respect to both 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) and nicotinamide adenine dinucleotide phosphate (NADPH), with an equilibrium constant of inhibitor binding ($K_i\;=\;[E][I]/[EI]$) of $61{\pm}1.2\;{\mu}M$ and $157{\pm}4.4\;{\mu}M$, respectively. At the same conditions, $K_i$ and $IC_{50}$ for lovastatin were $2.2{\pm}0.1\;nM$ and 12.5 nM, respectively. Thus, the given peptide interacts with HMGR as a bisubstrate, consequently blocking access of both substrates to the active sites. The achieved results suggest the design of new peptide sequences having a higher relative affinity to binding sites of this enzyme and an enhancement of their hypocholesterolemic properties.

• Journal of the Korean Dietetic Association
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• v.7 no.4
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• pp.313-319
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• 2001

High serum cholesterol level is a major risk factor for coronary heart disease(CHD). Nutrition therapy of hypocholesterolemic diets with increased physical activity is the essential step in the treatment of the hypercholesterolemic patients. The purpose of this study was to evaluate the short-term effect of intensive dietary therapy combined with regular exercise in lowering serum cholesterol level. Seventy three hypercholesterolemic outpatients(mean: 268.0$\pm$24.7mg/dL), aged 34 to 73(mean: 56$\pm$9.8yrs), who visited cardiology OPD of Yonsei Cardiovascular Center from April through October, 1998 were studied. Anthropometric measurements, usual nutrient intake survey using semiquantitative food frequency questionnaire, and daily nutrient intake analysis were performed. The nutrition counseling for the hypocholesterolemic diet and exercise therapy was performed individually. After a 4 week intensive dietary therapy, comparisons of body weight, nutrient intakes, and blood lipid concentrations were evaluated for the hypocholesterolemic effect of intensive diet therapy. After 4 weeks of intensive diet therapy, significant reductions in percent ideal body weight(p<0.01), saturated fat intake(p<0.01), and cholesterol intake(p<0.01) were observed. There were significant reductions in serum total cholesterol and LDL-cholesterol levels after 4 weeks of therapy by 8.1%(p<0.01) and 9.7%(p<0.01), respectively. Our results showed that intensive dietary therapy was effective in reductions of serum total and LDL-cholesterol levels. The goal for this dietary modification should not be temporary but rather be permanent in eating behavior accompanied by appropriately increased physical activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.358-369
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• 1997

Hypercholesterolemia is a main risk factor to develop cardiovascular disease, a major cause of death in Korea currently. Dietary factors which shows hypocholesterolemic effect have been reported, which includes plant proteins, unsaturated fatty acids, milk, calcium, flavonoids. Numerous animal and human studies confirmed the pronounced hypocholesterolemic effects of soluble dietary fiber, such as psyllium husk, pectin, sodium alginate, guar gum. Several hypotheses have been proposed to explain the hypocholesterolemic effect of dietary fiber, including binding of bile acids by fiber, interference of lipid absorption and reduced hepatic cholesterol synthesis by propionate, a product of soluble dietary fiber fermentation. Several other hypotheses have been proposed, and these hypotheses are not mutually exclusive.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.513-524
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• 1993

mechanisms for the hypocholesterolemic effects of $\beta$-glucan remain unclear. Rats were divided into 3 groups ; normal control group, atherogenic group(oral administration of cholesterol 40 mg/kg/day plus vit. $D_2$ 320,000 IU/kg/day), $\beta$-glucan treatment group(atherogenic treatment plus $\beta$-glucan 0.135 g/kg/day). The $\beta$-glucan treatment group showed moderate increases of serum lipids concentration compared with atherogenic group. In histopathological examination, aortas showed no critical lesions. The total fecal neutral sterols and bile acids excreted for 6 days was increased compared with both normal and atherogenic group. To compare effects of soluble fiber and insoluble fiber extracted from barley on postprandial lipemia, 5 healthy male adults ingested on separate days a low-fiber(total dietary fiber 2.61g) control meal or dietary fiber-enriched(12.61g) meals. Fasting and postprandial blood samples were obtained for 6.5h and serum lipids were analyzed. The serum total lipids, total cholesterols, LDL & VLDL-cholesterol were markedly reduced with soluble fiber-enriched meals, but no decrease with insoluble fiber-enriched meals. These results suggest that mechanisms for the hypocholesterolemic effect of $\beta$-glucan on rats were due to the inhibition of cholesterol absorption in the intestinal lumen and acceleration of cholesterol catabolism in the liver. And the soluble dietary fiber($\beta$-glucan) has the hypocholesterolemic effect by dropping serum LDL & VLDL-cholesterol in the clinical study.

• Journal of Nutrition and Health
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• v.28 no.2
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• pp.107-114
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• 1995

These works were designed to examine the effects of dietary fiber sources and levels on lipid metabolism in rats fed high lard diet. Rats were divided into three($\alpha$-cellulose, polydextrose, carrageenan) groups and were fed with containing 6% fiber diet. Serum, liver and fecal lipid contents were examined after four weeks of dieting. Also, in order to investigate whether hypocholesterolemic effect of dietary fiber at 4 weeks is continued at 8 weeks, rats were fed with diets containing same sources with different levels of each dietary fiber and were sacrificed after eight weeks of dieting. Serum cholesterol in rats fed carrageenan diet and polydextrose diet were reduced compared with $\alpha$-cellulose-fed group at both four and eight weeks dieting. Liver cholesterol in both polydextrose-fed and carrageenan-fed group were lower than $\alpha$-cellulose-fed group. Fecal total group were increased compared with $\alpha$-cellulose-fed group. On the other hand, there was no significant difference between polydextrose-fed and carrageenan-fed group. On the basis of the results, it was suggested that the hypocholesterolemic effect of soluble fiber used in this study (polydextrose, carageenan) on rats was due to the inhibition of cholesterol absorption on the intestinal lumen and acceleration of cholesterol catabolism in the liver and enhancement of bile acids excretion. On the other hand, insoluble fiber($\alpha$-cellulose) showed no hypo-cholesterolemic effect.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.141-149
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• 2013

The objective of this study is to find the effect of improving hyperlipidemia through Platycodi radix saponin. A hypercholoesterol diet and Platycodi radix saponin methanol extract were supplemented to the 6 week old male Spargue Dawley rats for four weeks. Results showed that the serum total cholesterol, triglyceride and LDL-cholesterol level decreased in the group supplemented with Platycodi radix saponin methanol extract(p<0.05), however, the serum total lipid and HDL-cholesterol did not show any difference from the control group according to the supplement of Platycodi radix saponin methanol extract. In the group supplemented with Platycodi radix saponin methanol extract, the total cholesterol decreased by 20%, triglyceride by 36% and LDL-cholesterol by 25% respectively, and there was no difference according to the level of Platycodi radix saponin methanol extract. AI(atherogenic index) and CRF(cardiac risk factor) were low in the group supplemented with Platycodi radix saponin methanol extract. Total lipid, total cholesterol and triglyceride in liver and feces were significantly low in the group supplemented with the Platycodi radix saponin methanol extract compared with the control group(p<0.05). According to this result, it is expected that the Platycodi radix saponin methanol extract supplemented in the hypercholesterol diet can lower atherosclerosis, the cause of cardiovascular disease, by reducing not only serum cholesterol and triglyceride but also liver cholesterol and triglyceride.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.382-386
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• 1998

A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.109-120
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• 1993

Mechanisms for the hypocholesterolemic effetcs of $\beta$-glucan remain unclear. Rats were divided into 3 groups; normal control group, atherogenic group(oral administration of cholesterol 40 mg/kg/day and vitamin $D_2$320,000 IU/kg/day),${\beta}$-glucan treatment group(oral administration of atherogenic treatment and ${\beta}$-glucan 0.135 g/kg/day). The ${\beta}$-glucan treatment group showed moderate increases of serum lipids concentration compared with atherogenic group. In histopathological examination, aortas showed no critical lesions. The total fecal neutral sterols and bile acids excreted for 6 days was increased compared with both normal and atherogenic group. These result\ulcorner suggest that mechanisms for the hypocholesterolemic effect of ${\beta}$-glucan on rats were due to the inhibition of cholesterol absorption in the intestinal lumen and acceleration of cholesterol catabolism in the liver.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.10a
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• pp.152-152
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• 2003

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.562-569
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• 2010

This study was conducted to investigate the hypocholesterolemic effects of porphyran and insoluble dietary fiber isolated from laver in rats fed high fat diet containing 1% cholesterol, 0.25% sodium cholate and 12% lard. Rats were fed, ad libitum, diets containing 5% diet fiber as cellulose(normal control or high fat control), porphyran or insoluble dietary fiber for 4 weeks. Among the groups fed high fat diet, liver weight was significantly lower in high fat porphyran group than high fat control. Plasma GOT, GPT, total cholesterol, cholesteryl ester, LDL-cholesterol and liver total cholesterol concentration were significantly lower in high fat porphyran group than high fat control. The feeding of porphyran significantly increased fecal cholesterol and bile acid excretion. The feeding of insoluble dietary fiber had no significant effect on either plasma or liver cholesterol levels, although fecal cholesterol level in the insoluble dietary fiber group was significantly higher than that in the high fat control. The results indicate that porphyran isolated from the laver may exert their hypocholesterolemic effect by increasing excretion of fecal bile acid and cholesterol.