• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.816-821
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• 1999

Cholesterol esterase(pCEH, pancreas cholesterol ester hydrolase, E.C.3.1.1.13) which is secreted from pancreas has been known as an important lipase for cholesterol uptake. cholesteryl acyl esters from a diet must be hydrolyzed to free cholesterol and fatty acid by cholesterol esterase before the absorption in small intestine. For the development of inhibitory substances from natural source, we screened many extracts of oriental herbs for the inhibition of cholesterol esterase in vitro. The ethanol extract of Ephedra herba showed strong inhibitory activity. Solvent fractionation and silica gel column chromatography with the extract lead to the purification of the inhibitory principle in Ephedra herba. Crystallized inhibitor was identified as ( ) ephedrine by using UV, FT IR, 1H NMR, 13C NMR and GC/Mass. These results suggest that ( ) ephedrine can be used as a potential lead compound for the development of inhibitor for cholesterol uptake by cholesterol esterase inhibition.

• Applied Chemistry for Engineering
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• v.34 no.6
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• pp.660-664
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• 2023

In this study, a new system to determine the concentration of cholesterol using a color change was developed. The system comprised diacetylene vesicles and cholesterol oxidase (ChOx). 10,12-Pentacosadiynoic acid (PCDA) was used as the diacetylene compound, and PCDA vesicles were formed using sonication. The H₂O₂ produced during the reaction between cholesterol and ChOx was used to initiate the polymerization of the PCDA in the vesicles. During polymerization, the vesicles changed from colorless to blue. Therefore, the cholesterol concentration was proportional to the intensity of the blue color. The absorption at 665 nm indicated that the blue color was directly proportional to the cholesterol concentration. This indicates that the system can be used for cholesterol detection. The minimum cholesterol concentration detected using this system was 1.0 mM.

• Journal of Applied Biological Chemistry
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• v.44 no.3
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• pp.131-134
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• 2001

Effects of water-soluble extract from roasted-chicory root on the cholesterol metabolism in rats fed cholesterol diet were investigated. Sprague-Dawley rats received a hypercholesterolemic diets without (control group) or with 5.0% water-soluble extract from roasted chicory root for 2 weeks. Roasted chicory extract group showed significantly higher body weight gain and food intake compared with the control group. The concentrations of total cholesterol and LDL+VLDL cholesterol in serum were significantly lower in rats fed roasted chicory extract diet. However, HDL-cholesterol concentration, and atherogenic index were not significantly affected by the dietary roasted chicory extract. Fecal net weight, fecal cholesterol, and bile acid excretion were significantly higher in the chicory extract group. The results suggest that the hypocholesterolemic effect in rats fed roasted chicory extract may be caused by an alteration in the absorption of cholesterol by an increase in the fecal excretion of cholesterol and bile acid.

• Journal of Nutrition and Health
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• v.30 no.6
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• pp.622-633
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• 1997

This study was to investigate the effects of chitin, chitosan , NOCC and cellulose on cadmium toxicity and lipid metabolism in rats. Fifty male rats of Sprague-Dawley strain weighing 155$\pm$17g were divided into 10 groups according to body weight, and were raised for 5 weeks. Levels of 0 and 400 ppm of cadmium chloride were in the diets. And chitin, chitosan , NOCC and cellulose were given at the level of 0 and 4%(w/w) of the diets. Chitosan and NOCC decreased Cd concentration of liver and kidney, and increased the fecal excretion of Cd. Although cellulose was less effective, cellulose also decreased Cd concentration of liver and increased fecal Cd excretion . However chitin had little effect on alleviating Cd toxicity. In addition, chitosan and NOCC lowered total lipid, cholesterol and triglyceride contents in serum and liver by decreasing the lipid absorption. The lowering of cholesterol especially had a remarkable effect. Although it was less effective than chitosan and NOCC, chitin decreased the lipid absorption ratio and lowered cholesterol contents in serum and liver. In conclusion , chitosan and NOCC showed effects of decreasing the absorption of Cd and lipid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.477-483
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• 1999

The effects of chitin and chitosan on the contents of plasma and liver lipids and the fecal excretion of neutral and acidic steroids were investigated in rats fed with atherogenic diet. Dietary chitin did not affect plasma total cholesterol, LDL cholesterol and HDL cholesterol, while chitosan diet de creased total cholesterol and LDL cholesterol. Plasma content of triglyceride was reduced signif icantly by chitin diet but not by chitosan. Increases in fecal weight were observed in rats fed with either chitin or chitosan, and the increase was greater with chitosan than with chitin. Dietary chitosan resulted in an increase of fecal excretion of neutral steroids without any changes in the excretion of acidic sterols. Putting the results together, dietary chitosan reduces plasma cholesterol probably due to the reduction of cholesterol absorption. The decrease in plasma triglyceride level by dietary chitin requires further research to understand the mechinism.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.999-1005
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• 1998

This study was conducted to investigate the effect of late-harvested green tea extract on serum and tissue lipid contents and Ca absorption. Sprague-Dawley male rats weighing 200g were fed high fit diets containing no tea(control), 0.5%(0.5LG), 1.0% late-harvested green tea extract(1.0LG), and 1.0% early-harvested green tea extract(1.0EG) for 4 weeks. Though daily food intake of experimental groups showed no significant difference from that of control group, daily body weight gain and food efficiency ratio were lower in all groups fed green tea extract. The contents of serum triglyceride of 1.0LG and 1.0EG groups and the content of serum total cholesterol of 1.0LG group were significantly lower than those of control group. The values of serum HDL-cholesterol in groups fed green tea extract were higher than that in the control group. LDL-cholesterol and atherogenic indices of all groups fed green tea extract were significantly lower than those of the control group. The contents of total lipid and triglyceride in liver were significantly lower in only 1.0LG group. For epididymal fit pad, the contents of total lipid and triglyceride in 1.0LG and 1.0EG groups were lower than those in the control group. The contents of total lipid excreted in feces were higher in groups fed diets of 1.0% green tea extract. There was no significant difference among experimental groups in Ca absorption. These results suggest that the administration of late-harvested green tea extract decreases the contents of fat in the body without reducing Ca absorption. (Korean J Nutrition 31(6) : 999-1005, 1998)

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2001.12a
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• pp.74-87
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• 2001

Evidence shows that the serum level of cholesterol (CH) is decreased with increasing green tea (GT) consumption. This presentation summarizes our recent findings on the effect of GT extract on intestinal absorption of [$^{14}C$-labeled CH and phosphatidylcholine (PC). Ovariectomized (OX) adult rats were infused intraduodenally with lipid emulsions containing radiolabeled lipids [$^{14}C$-CH or $^{14}C$-phosphatidylcholine (PC)] in the presence of GT extract or catechins to determine the rates and amounts of CH absorption and the intestinal hydrolysis and lymphatic output of PC. During lipid infusion, lymph was collected hourly for 8 h. The lymphatic absorption of $^14C$-CH was drastically lowered by infusion of GT extract at two dosage levels (GTl =5.4 mg catechins/h and GT2 = 15.1mg catechins/h). The cumulative lymphatic absorptions of $^{14}C$-CH in rats infused with GT1 and GT2 were 20.7$\pm$4.3 and $4.8{\pm}4.1{\%}$ dose, respectively, whereas the absorption of $^{14}C$-CH in rats infused with no GT extract (GT0) was $36.3{\pm}1.1{\%}$ dose. GT extracts also significantly lowered the absorption of-tocopherol (TP) in a dose dependent manner ($29.6{\pm}4.9{\%}$ dose in GT0, $20.8{\pm}5.8{\%}$ dose in GTl, and $7.9{\pm}5.4{\%}$ dose in GT2 groups). Both (+)-catechin and EGCG significantly lowered the lymphatic outputs of $^{14}C$-radioactivity after intraduodenal $^{14}C$-PC infusion. A significantly higher amount of $^{14}C$-PC remained unhydrolyzed in the intestinal lumen of the EGCG rats ($22.8{\%}$) compared with the (+)-catechin ($15.8\%$) and control groups ($11.9\%$). GT extracts, (+)-catechin, and EGCG significantly reduced the absorption of TP. The inhibitory effect of GT extract and catechins on lipid absorption may be mediated in part through the inhibition of pancreatic PLAz. The findings provide the first direct evidence that green tea and catechins have a profound inhibitory effect on the intestinal absorption of CH in OX rats. Results suggest that green tea and catechins may be used as a dietary or pharmacological means of lowering cholesterol absorption.

• Journal of Nutrition and Health
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• v.31 no.5
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• pp.914-920
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• 1998

The effect of dietary pectin, tangerine pulp meal, propionate, lactate or fumarate on cholesterol (C) and triacylglycerol(TG) levels in the serum and liver, and the effect of pectin on dietary C absorption were studied in a series of three experiments. Mature female Sprague Dawley rats were fed a control diet or diets containing 5% pectin, 5% tangerine pulp meal, 3% propionate, 3% lactate 3% fumarate, or 10% pectin. Serum total C levels were lower(p<0.05) in rats fed the diet containing 5% pectin than in control rats after a 4-week feeding period(93.8 vs 119.2mg/100mL). Serum HDL, LDL+VLDL C levels were not different among diet groups. Liver total C level was also lower(p<0.05) in rats fed the diet containing 5% pectin than in control rats, but liver TG level was not influenced by diet. Dietary propionate, lactate or fumarate did not reduce serum C, indicating that propionate is not a regulator of serum C. However, dietary pectin(10%) increased fecal excretion of dietary C(or its metabolites) more than 70% over a control value. Our data indicate that dietary pectin reduces serum and liver C levels by increased fecal secretion of dietary C, but not by its fermentation product propionate or other gluconeogenic substrates. (Korean J Nutrition 31(5) : 914∼920, 1998)

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.113-118
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• 1993

The lowering effect of cholesterol in Sprague Dawley rats was investigated with panaxydol which was purified from the petroleum ether soluble fraction(PESF) of Korean red ginseng. The level of total cholesterol(TC), Triglyceride(TG) and low density lipoprotein(LOL)-cholesterol in serum was reduced by $48\%,\;47\%\;and\;41\%,$ respectively while high density lipoprotein(HDL)-cholesterol was in creased up to $29\%$ as compared with their control values when the panaxydol(20 umoles. 5 mq/kq/day) was adminstered by intraperitoneal rout for 3 consecutive days along with a $1\%$ cholesterol diet. The hepatic ester cholesterol content which was increased in proportion to the cholesterol content of the diet in the control, clearly decreased with panaxydol administration to about $40\%$ regardless of the two diet cholesterol content. $1\%\;or\;2\%.$ A threshold of supression on the serum lipid levels in both administration routes was observed: the maximium suppression in i.p. and p.o. administration was observed to be at 5mq/kq b.w. and in the range of 50 - 100 mg/kg b.w., respectively. Panaxydol may reduce serum lipid and cholesterol levels by inhibiting cholesterol absorption and/or by modulating the cholesterol metabolism. at least in part.

• Journal of Nutrition and Health
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• v.31 no.2
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• pp.135-142
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• 1998

This study was undertaken to determine whether dehulled defatted flour has an effect on postprandial plasma lipoprotein composition, hepatic lipid composition, enzyme and hormone levels in rats. Control(casein) and experimental (dehulled defatted soy flour)diets were fed to rats for 7 weeks. all animals (S. D. rats, male) were sacrificed 2 hrs after the feeding of 5g of each diet. Defatted soy flour feeding significantly lowered postprandial plasma total cholesterol, chylomicron/VLDL-cholesterol, hepatic cholesterol and triglyceride(TG) as compared with casein feeding, whereas no significant effect on plasma TG was observed. Intestinal kipase activity was elevated , whereas trypsin activity was suppressed in the dehulled defatted soy flour group. Plasma glucagon, thyroid hormone and hepatic HMG-coA reductase levels were not affected by diet treatment. These results hypothesize that dehulled defatted soy flour affects cholesterol digestion and absorption in guts, thus delaying the appearance of chylomicron cholesterol in plasma or affecting the disappearance of chylomicron remnant to high-density-lipoprotein(HDL).