• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.2
• /
• pp.263-270
• /
• 2002

In the recent studies, many researchers are interested in foods as functional components rather than nutrient sources. Cow's milk is considered as an excellent food sources because of its many nutrients. Casein is a major milk protein and has been reported to have hyperlipidemic and hypercholesterolemic effects. But several reporters have suggested that peptide fractions and hydrolysate of casein have hypolipidemic effects differing from intact protein, casein. Therefore, the objective of the study was to investigate how the casein peptide fractions affect lipid metabolism in rats fed normal or high fat diets. The peptide fractions and hydrolysate of casein were obtained by casein hydrolysis with trypsin. The male rats (Sprague-Dawley), weighing approximately 150 g, were fed each experimental diet containing casein (CAS), casein hydrolysate (CH), casein hydrolysate precipitate (Cpt) and two kinds of peptide fractions (CL & CB) for three weeks, respectively. In the exit I, the male rats were fed normal fat diets (7% soybean oil & cholesterol-free; Expt. I), and in the expt II, fed high fat diets (18% beef tallow & 1% cholesterol; Expt. II). Crude protein contents were calculated from nitrogen contents. Amino acid composition of each fraction was also analyzed. The concentration of total lipid, total cholesterol and triglyceride in serum, liver and feces were measured. As the results of study, tole rats fed peptide fractions with normal fat diets (Expt. I) had no effects on total lipid, total cholesterol and triglyceride concentration in serum and liver and fecal excretion. However, in the rats fed hydrophobic casein peptide fractions (CB) with high fat diet, fecal lipids excretion were significantly increased and the lipids concentration of serum and those of liver tended to decrease, numerically.

• Journal of Food Hygiene and Safety
• /
• v.16 no.2
• /
• pp.117-124
• /
• 2001

The main constituent of green tea, catechins have been reported to have numberous biological anti-vites including antimutagenic, antibacterial, hypocholesterolemic, antioxidant and antitumor properties. In the present study, we examined the protective effect of catechin on UVB-induced skin damage. Catechin (3 mg/mouse) was topically treated to dorsal area of SHK-1 hairless mouse daily for 2 weeks. UVB (100 mJ/$\textrm{cm}^2$) was also treated soon after application of catechin alone or with catechin for 2 weeks. Catechin reduced UVB-induced infiltration of inflammatory cells, fibrosis of cells and collagen-fiber formation. In addition, catechin also prevented UVB-induced DNA fragmentation and apoptosis cell number, but not changed p53 level. Furthermore catechin inhibited UVB-induced cell proliferation. There results showed that catechin have preventive effect aganinst UVB-induced skin damages. and these effects could contribute to the antitumor promoters activity.

• Journal of Nutrition and Health
• /
• v.24 no.4
• /
• pp.314-325
• /
• 1991

To compare the hypolipidemic effects of n6 and n3 PUFA at different fat levels, male Sprague Dawley rats were fed either low fat (LF, 10% Cal) or high fat (HF, 40% Cal) diet which was different only in fatty acid composition for 6 weeks. Dietary fats were beef tallow, corn oil, perilla oil, and fish oil concentrate as a source of saturated fatty acid, n6 linoleic acid(LA). n3 ${\alpha}-linolenic$ acid(LL) and n3 eicosapentaenoic acid(EPA)+docosahexaenoic acid(DHA), respectively. VLDL fraction was separated by ultracentrifugation and chemical composition was determined by thin layer chromatography. Plasma cholesterol level was increased by n6 LA but decreased by n3 LL and n3 EPA in LF and HF diets, and the hypocholesterolemic effect of n3 EPA was most significant in HF diet. HDL-Chol level was raised by n6 LA in LF and HF diets, but significantly reduced by n3 EPA in HF. Plasma TG level was reduced by n6 LA n3 LL and EPA in LF and HF with the reduction of lipogenic enzyme activity only by n3 PUFAs. The proportion of TG in VLDL fraction was significantly lowered by n3 EPA in LF and HF. The proportion of apo-B in VLDL fraction was not changed in LF, but was significantly decreased in HF by n3 EPA. Therefore, the hypotriglyceridemic effect of n3 PUFA could be from the reduced lipogenesis in liver and resulted in the depressed secretion of TG as VLDL in LF and HF with significant lower production of apoB in HF diet.

• Journal of Dairy Science and Biotechnology
• /
• v.31 no.2
• /
• pp.99-108
• /
• 2013

Kefir is a unique fermented dairy product resulting from combined lactic acid and alcoholic fermentation of lactose in milk. Kefir is produced by the microbial activity of kefir grains. Kefir has numerous health benefits such as the reduction of cholesterol levels, stimulation of the immune system, antimutagenic and anticarcinogenic properties, and improvements of lactose intolerance. Furthermore, kefir is excellent as both a dietetic beverage and for protection against various diseases in small babies. Therefore, kefir has recently been regarded as an important functional dairy food. To date, the majority of research on kefir has focused on the applications of functional kefir using advanced biotechnology methods. The purpose of this review article is to facilitate the recognition of kefir as a novel functional food.

• Journal of Life Science
• /
• v.9 no.1
• /
• pp.35-43
• /
• 1999

Leaf protein (LP) was prepared by centrifugation the green juice from Italian ryegrass (Lolium multiflorum Lam.) at acid precipitation. LP was compared with casein and soybean protein isolate for their concentration of serum lipids and free amino acids in Wistar male rats for 2 weeks. Each protein source was incoporated into cholesterol free, low-fat diet to provide a protein level of 20%. A comparison of serum amino acids in leaf protein-fed vs. casein-fed rats showed that, glycine was the only amino acid having a higher concentration whereas concentration of other amino acids were lower in the leaf protein-fed rats compared with the casein-fed rats. Further alanine was significantly lower in the leaf protein-fed rats compared with the casein-fed rats, and the protein-induced differences in glycine and alanine concentration of unfed rats were reproducible. Concentration of several amino acids, rarticularly valine, leucine and tyrosine, also changed when serum cholesterol concentrations varied, but these effects could not be explained by our experiments. The results suggest that a change in serum concentration of glycine and alanine of unfed rats may be related to the change in serum cholesterol concentration. These data also suggest appear to function in a similar way to soybean protein in their hypocholesterolemic action.

• Korean Journal of Food Science and Technology
• /
• v.40 no.1
• /
• pp.96-100
• /
• 2008

Pungent oils are fat sources that determine the taste, flavor, and satiety of foods. They are also energy sources and regulators of lipid metabolism in humans. The present study was performed to evaluate the effects of red pepper (Capsicum annuum L.) seed oil (RPO) and sancho (Zanthoxylum schinifolium) seed oil (SCO) as pungent oils on the lipid profiles of rats fed on hypercholesterolemic diets (0.12% cholesterol), as compared to common soybean oil (SBO). There were large differences in the n-6/n-3 fatty acid ratios of the experimental oils (SBO: 8.8, SCO: 1.2, RPO: 70.1). Serum cholesterol concentrations were higher in the RPO groups than in the other groups; whereas ratios of HDL-cholesterol/total cholesterol were lower in the RPO groups. On the other hand, liver cholesterol levels were markedly higher in the SCO groups than in the RPO groups, with the SBO groups having intermediate levels; these largely reflected cholesterol ester content differences in the rat livers. It is possible that the different serum cholesterol responses observed in the RPO and SCO groups might have been related to differences in the n-6/n-3 fatty acid ratio rather than the polyunsaturated fatty acids/saturated fatty acids ratio. Serum triacylglycerol concentrations were lower in the SCO groups as compared to the other groups. Overall, the results showed a hypocholesterolemic effect for sancho seed oil as compared to red pepper seed oil in rats fed diets containing 0.12% cholesterol.

• Korean Journal of Poultry Science
• /
• v.32 no.1
• /
• pp.49-54
• /
• 2005

An experiment was conducted to investigate whether dietary yeast (Saccharomyces cerevisiae, SC) and its' structural components, i.e., yeast cell-extract (YE) and yeast cell-wall (CW) could influence growth performance, ileal morphology and serum lipids of male broiler chickens. There were four dietary treatments, each consisting of 6 replicates (10 birds per replicate). Chickens were fed a corn-soybean meal base control diet and diets containing SC ($0.5\%$), YE ($0.25\%$) and CW ($0.25\%$), respectively for 5-wk-experimental period. Dietary SC, YE and CW versus the control diet did not affect growth performance of male broiler chickens. Ileal morphology as to villus height, crypt depth and villus:crypt ratio of birds fed on the control diet was not significant from those fed on diets rich in SC, YE and CW, respectively. Dietary SC significantly lowered (P<0.05) serum total cholesterol by on average $19.7\%$ as compared to the control group. In addition, chickens fed on diets with either YE or CW lowered serum cholesterol by on average 15.3 and $12.5\%$, respectively as compared to the control albeit that the former only reached statistical significance. In conclusion, our study observed the hypocholesterolemic effect of SC in male broiler chickens. Moreover, YE, i.e., an extract of intracellular components of SC contains active molecules that are responsible far lowering serum cholesterol concentrations, but their identification at the molecular level needs to be assessed.

• Korean Journal of Food Science and Technology
• /
• v.33 no.5
• /
• pp.633-640
• /
• 2001

This study investigated the effects of lipid metabolism on male Sprague Dawley rats given porphyran diet extracted from Porphyra yezoensis for 4 weeks. We divided into 5 diet groups which were normal diet, control diet fed high fat, cholesterol and sodium cholate, control and 1% porphyran diet (1% PD), control and 5% porphyran diet (5% PD), control and 10% of porphyran diet (10% PD). Feed intake and weight gain were not significantly different between control and porphyran diet. Serum triglyceride, total cholesterol and LDL-cholesterol contents were significantly (p<0.05) lower in porphyran diet groups than control group. However, serum HDL-cholesterol contents increased by the addition of porphyran in experimental diet. Hepatic triglyceride and total cholesterol concentrations were proportionally decreased by the addition of porphyran in control diet compared to control diet. A number of lipid particles were shown in liver tissue of control group and the same appearance was shown in the group fed with 1% porphyran diet, whereas lipid particles was reduced in the group fed with 5% and 10% porphyran diet compared to control group. Especially, liver tissue of 10% porphyran diet group was shown similar appearance to normal diet group. These results indicated that supplementation of porphyran in hyperlipidemic rats has an effect on the improvement of serum lipids.

• Journal of Nutrition and Health
• /
• v.47 no.3
• /
• pp.157-166
• /
• 2014

Purpose: Rice bran is a byproduct of the hulling of rice and contains a variety of bioactive components. Various studies have reported on the antioxidative, anticancer, immune-enhancing, and hypocholesterolemic effects of rice bran. However, few studies about the physiological activity of stabilized rice bran supplement on dietary intake of sugars is limited. The aim of this study was to investigate the effect of stabilized rice bran supplement on blood glucose in C57BL/6 mice fed a high sucrose diet. Methods: Animals were randomly divided into three groups respectively, and were fed a normal diet (ND group), a high sucrose diet (HSD group) or a high sucrose diet containing 20% stabilized rice bran (HSD-SRB group) for 12 weeks. Results: In the oral glucose tolerance test (OGTT), after seven weeks of feeding on the experimental diets, a significantly lower result was observed for HSD-SRB than for HSD at 30 and 60 minutes after oral administration in glucose solution (2 g/kg body weight). The incremental area under the curve (IAUC) of HSD-SRB was significantly lower than that of HSD. After 12 weeks, fasting blood glucose level of HSD-SRB was significantly lower than that of HSD. No significant difference in the serum insulin level was observed between HSD and HSD-SRB. However, HOMA-IR was significantly decreased in HSD-SRB compared to HSD. In addition, HOMA ${\beta}$-cell was significantly increased in HSD-SRB compared to HSD. Triglyceride in liver of HSD-SRB was significantly lower than that of HSD. Conclusion: Feeding diets containing 20% rice bran improved insulin resistance and insulin secretion by decreasing triglyceride in liver. Thus, rice bran has a positive effect on glycemic control. In addition, the results are expected to be utilized as a basis for human study and development of food products with added rice bran.

• Journal of Korean Medicine Rehabilitation
• /
• v.31 no.4
• /
• pp.117-127
• /
• 2021

Objectives Previously, we demonstrated that a 5% ethanol extract of unripe Rubus coreanus (5-uRCK) and ellagic acid has hypocholesterolemic and antiobesity activity in high-fat diet-fed animals. Therefore, we conducted a clinical study on the anti-obesity effect of 5-uRCK in 140 Korean adults (aged 19-70 years, body mass index (BMI) ≥25 kg/m²). Methods The participants were randomly assigned to two groups and were administered the placebo (n=70) or 5-uRCK extract (800 mg, n=70) daily for 12 weeks. The subjects were instructed to maintain their usual dietary intake and normal physical activity. Anthropometrics, body composition (dual-energy X-ray absorptiometry), and blood parameters were compared between the two groups. Results Average body weight and BMI did not show any significant changes; however, changes in upper body fat mass between the two groups was significantly different, as determined using analysis of covariance adjusted for baseline of percent body fat and drinking units. Moreover, Although not significant, the trunk fat mass and percent trunk fat tended to decrease after 5-uRCK supplementation. There was no significant difference in other laboratory biomarkers between the two groups. All safety parameters were within normal ranges in the both group. Conclusions In the present study, 5-uRCK significantly reduced upper body fat in obese subjects after 12 weeks, which indicates that it may help improve android-type obesity. Furthermore, the supplement is safe and well tolerated.