• Preventive Nutrition and Food Science
• /
• v.22 no.2
• /
• pp.67-80
• /
• 2017

Cholesterol is a vital component of the human body. It stabilizes cell membranes and is the precursor of bile acids, vitamin D and steroid hormones. However, cholesterol accumulation in the bloodstream (hypercholesterolemia) can cause atherosclerotic plaques within artery walls, leading to heart attacks and strokes. The efficiency of cholesterol absorption in the small intestine is of great interest because human and animal studies have linked cholesterol absorption with plasma concentration of total and low density lipoprotein cholesterol. Cholesterol absorption is highly regulated and influenced by particular compounds in the food supply. Therefore, it is desirable to learn more about natural food components that inhibit cholesterol absorption so that food ingredients and dietary supplements can be developed for consumers who wish to manage their plasma cholesterol levels by non-pharmacological means. Food components thus far identified as inhibitors of cholesterol absorption include phytosterols, soluble fibers, phospholipids, and stearic acid.

• Nutrition Research and Practice
• /
• v.3 no.1
• /
• pp.9-14
• /
• 2009

Aloe products are one of the top selling health-functional foods in Korea, however the adequate level of intake to achieve desirable effects are not well understood. The objective of this study was to determine the intestinal uptake and metabolism of physiologically active aloe components using in vitro intestinal absorption model. The Caco-2 cell monolayer and the everted gut sac were incubated with $5-50{\mu}M$ of aloin, aloe-emodin, and aloesin. The basolateral appearance of test compounds and their glucuronosyl or sulfated forms were quantified using HPLC. The % absorption of aloin, aloe-emodin, and aloesin was ranged from 5.51% to 6.60%, 6.60% to 11.32%, and 7.61% to 13.64%, respectively. Up to 18.15%, 18.18%, and 38.86% of aloin, aloe-emodin, and aloesin, respectively, was absorbed as glucuronidated or sulfated form. These results suggest that a significant amount is transformed during absorption. The absorption rate of test compounds except aloesin was similar in two models; more aloesin was absorbed in the everted gut sac than in the Caco-2 monolayer. These results provide information to establish adequate intake level of aloe supplements to maintain effective plasma level.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.3
• /
• pp.396-401
• /
• 1994

The effect of vitamin B12 status and pectin feeding on vitamin B12 absorption in rats were studied. Rats in low, medium, and high vitamin B12 status were fed either fiber-free or 10% pectin diet and absorption of a single oral dose of vitamin B12 status of rats was verified by urinary methylmalonic acid and liver vitamin B12 measurements. Absorption of vitamin B12 tended to increase as the rats became deficient in vitamin B12 , although the difference was not significant . Pectin inhibited absorption of vitamin B12 regardless of the vitamin B12 status of the rats. The results demonstrated that inhibition of vitamin B12 absorption by pectin would be a possible mechanism for the impairment of vitamin B12 status due to chronic pectin feeding.

• The Korean Journal of Food And Nutrition
• /
• v.15 no.1
• /
• pp.7-11
• /
• 2002

This study was performed to estimate fille zinc absorption, excretion, and balance of preschool children in Pohang and to evaluate the relationship zinc absorption and related variables. To determine the zinc absorption and excretion, duplicate food samples, pooled faces and urine samples were collected for 3 consecutive days in 21 preschool children. The mean fecal and urine excretions were 7.03mg/day and 0.16mg/day far the boys and 5.87mg/day and 0.15mg/day for the girls. Analyzed daily mean zinc intake was 10.45mg/day for the boys and 7.80mg/day for the girls. The mean ,apparent absorption rate and balance were 29.7% and 3.25mg for the boys and 23.3%, 1.78mg for the girls. Although the mean apparent absorption rate and balance of boys tended to be higher, there was no significant difference between boys and girls. In this study, subjects showed the positive balance except one. Fecal zinc loss reflected dietary zinc (p < 0.01), but urinary zinc loss was unaffected by zinc intake. There was a positive relationship between zinc apparent absorption and zinc balance (p<0.01). These results show that the zinc absorption and balance were favorable.

• Journal of Nutrition and Health
• /
• v.23 no.6
• /
• pp.427-433
• /
• 1990

The effect of short term feeding of various levels of pectin on vitamin B$_{12}$ absorption was studied. Rats fed fiber-free(FF) diet were divided into FF, 2% pectin, 5% pectin or 10% pectin diet group prior to the vitamin B$_{12}$ absorption test. On the day of the absorption test, absorption of a single oral dose of 57-Co-vitamin B12 was measured while rats were consuming their assigned diet. 5 and 10% pectin diet significantly inhibited vitamin B$_{12}$ absorption when compared with FF diet. Pectin intake was inversely correlated with the absorption of vitamin B$_{12}$.

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

• Proceedings of the Korean Society of Food Science and Nutrition Conference
• /
• 2004.11a
• /
• pp.47-52
• /
• 2004

This study was conducted to determine the effects of egg phospholipids [(Phosphatidylcholine (PC) and sphingomyelin (SM)] on intestinal absorption of cholesterol and other lipids. Each rat with Iymph cannula was infused via a duodenal catheter at 3.0 mL/h for 8 h with a lipid emulsion containing triolein, cholesterol and PC in 24 mL PBS. The PC in the lipid emulsion was egg PC (EPC), hydrogenated egg PC (HPC), or soy PC (SPC). The EPC in the lipid emulsion markedly lowered the Iymphatic absorption of cholesterol, compared with SPC and a lipid emulsion containing no PC. The HPC further lowered the absorption of cholesterol. The phospholipid output was not affected by the source of PC infused. The total Iymphatic output of oleic acid (18: 1), the major fatty acid infused in the form of triolein, did not differ among the NPC, SPC and EPC groups, but was significantly lower in the HPC group. The findings provide the first evidence that EPC markedly lowers the Iymphatic absorption of cholesterol under in vivo conditions. The inhibitory effect of EPC appears to be due to the higher degree of saturation of its acyl groups relative to SPC, suggesting that the intestinal absorption of egg cholesterol may be reduced by the presence of PC in e99 yolk. Experiment 2 was designed to determine whether egg SM, structurally similar to PC, also inhibits the Iymphatic absorption of cholesterol. Egg SM lowered the Lymphatic absorption of cholesterol in a dose dependent manner. Likewise, SM lowered the Iymphatic absorption of oleic acid, whereas it had no effect on retinol absorption. SM at a high dose lowered the Iymphatic outputs of both PC and SM, whereas there was no such effect at a lower dose. These results also indicate that luminal egg SM has an inhibitory effect on the intestinal absorption of cholesterol and other lipids of relatively high hydrophobicity.

• Nutrition Research and Practice
• /
• v.2 no.1
• /
• pp.3-7
• /
• 2008

This study was carried out to investigate the efficacy of sn-2 palmitic acid-fortified vegetable oil (Sn2PA) on calcium absorption and to confirm the synergistic effects of fructooligosaccharide on calcium absorption. Male SD rats were fed 6 kinds of casein based diets containing vegetable oil (control), sn-2 palmitic acid-fortified vegetable oil (Sn2PA) and Sn2PA with fructooligosaccharide(Sn2PAFO) in two levels of calcium (normal 0.5% and high 1.0%) for 3 weeks. Total lipids, cholesterol, triglyceride and calcium in blood were measured. Feces were collected using cages for 4 days. Serum concentrations of total lipids and calcium were not significantly different among groups. However, serum triglyceride was significantly decreased by fructooligosaccharide supplementation regardless of dietary calcium level. The lipid absorption was not significantly different among experimental groups. Calcium absorption was significantly higher in Sn2PAFO group than other groups. Calcium solubility of intestine was increased by sn-2 palmitic acid supplementation. These results suggest that sn-2 palmitic acid and fructooligosaccharide supplementation could be beneficial for baby foods including infant formula, with regard to increasing absorption of calcium by more soluble calcium in the small intestinal content.

• International Journal of Human Ecology
• /
• v.4 no.1
• /
• pp.35-44
• /
• 2003

This study investigated the effects of dietary phyate reduction on the apparent absorption and biochemical parameters of iron status in young Korean women. Fourteen healthy, young women consumed low and high phytate diets for ten days of each experimental period. Duplicate diet samples, a fasting blood sample on day 9, and complete fecal samples for five consecutive days starting from day 5 of each diet period were collected. The iron content of diet and fecal samples were analyzed to calculate apparent absorption. Serum samples were analyzed for iron, ferritin, transferrin receptor and TIBC; transferrin saturation was also calculated. The apparent absorption of iron tended to increase in the low phytate period (32.51%) compared to the high phytate period (17.91%), but the difference was not significant (p=0.06). Serum ferritin decreased and serum transferrin receptor increased significantly during the low phytate diet although the mean values were within the normal range. Serum iron and transferrin saturation did not change significantly. In conclusion, the results indicated that reducing dietary phytate for ten days negatively affected iron nutritional parameters, but it moderately and positively affected apparent iron absorption in young Korean women. Further research on the long-term effects of a low phytate diet with an adequate iron content for vows Korean women is necessary.

• Nutritional Sciences
• /
• v.7 no.3
• /
• pp.151-157
• /
• 2004

The aim of this study was to investigate the effects of chicory fructan fiber supplementation on bone mineral density, apparent absorption of minerals and serum parameters related to bone turnover in postmenopausal women. Twenty-six healthy Korean postmenopausal women participated in the study. 1be participants were randomly divided into two groups in a double-blind parallel design and took one of the supplements for 3 months; either a placebo of 8g maltodextrins/sucrose mixture (control group) or 8g chicory fructan fiber (fructan group). During the 3-month experimental period no differences were found in bone mineral density (BMD) between the two groups. Apparent calcium absorption significantly increased by 42% in the fructan group, while that of the control group decreased by 29% as compared to the values at baseline. Urinary calcium excretion was not significantly different between the group;;. After 3 months, the level of serum alkaline phosphatase (ALP) was significantly lower in the fructan group than in the control group and deoxypyridinolin showed a trend toward a slight reduction. In conclusion, intake of chicory fructan fiber with a regular increases apparent calcium absorption in postmenopausal women.