• Nutrition Research and Practice
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• v.7 no.5
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• pp.373-379
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• 2013

The consumption of fruits and vegetables that have high polyphenol content has been previously associated with a reduced risk for cardiovascular disease. We investigated the effects of onion peel extract on plasma total antioxidant capacity, lipid peroxidation, and leukocyte DNA damage. This study was a randomized, double-blind, placebo-controlled, crossover trial. Healthy female subjects received either onion peel extract or placebo (dextrin) for two weeks, underwent a 1-week washout period, and then received the other treatment for an additional two weeks. After two weeks of onion peel extract supplementation, the total cholesterol level, low-density lipoprotein cholesterol level, and atherogenic index significantly decreased (P < 0.05). No changes were observed in activities of erythrocyte antioxidant enzymes or levels of lipid peroxidation markers following onion peel extract supplementation. Additionally, no significant difference was found in plasma antioxidant vitamin (retinol, tocopherols, carotenoids, and coenzyme Q10) levels or ex vivo $H_2O_2$-provoked oxidative DNA damage after onion peel extract supplementation. The present interventional study provides evidence of the health benefits of onion peel extract and demonstrates its effects in modulating lipid profiles in healthy young Korean women.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.553-560
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• 2005

The purpose of this study was to examine the lipid peroxidation, plasma antioxidant status and insulin resistance in childhood obesity. To this end, we measured blood lipid profiles, glucose, insulin concentrations, plasma antioxidant vitamins, baseline conjugated diene formation as a measure of LDL oxidation in vivo and TRAP (total radical trapping antioxidant potential) of 93 school children (58 nonobese, 35 overweight-obese). Insulin resistance was estimated by homeostasis model assessment of insulin resistance (HOMA-IR). The overweight-obese children showed significantly higher levels of leptin (p < 0.0001) and triglyceride (p < 0.05) and significantly lower level of plasma Iycopene (p < 0.001) and $\gamma$-tocopherol (p < 0.05) compared with the normal weight children. Furthermore, the levels of TRAP were significantly lower in overweight-obese children (p < 0.05). Significant positive relationships between plasma leptin and conjugated dienes formation (p < 0.005) and inverse relationship between plasma leptin and lipid corrected levels of $\beta$-carotene (p < 0.05), Iycopene (p < 0.05) were observed. Our results showed an increased lipid peroxidation and decreased antioxidant capacity in childhood obesity which could be involved in the atherosclerotic process.

• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.310-318
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• 2023

Microalgae are attracting much attention as promising, eco-friendly producers of bioenergy due to their fast growth, absorption of carbon dioxide from the atmosphere, and production capacity in wastewater and salt water. However, microalgae can only accumulate large quantities of lipid in abiotic stress, which reduces productivity by decreasing cell growth. In this study, the strategy was investigated to increase cell viability and lipid production by overexpressing S-adenosylmethionine (SAM) synthetase (SAMS) in the microalga Chlamydomonas reinhardtii. SAM is a substance that plays an important role in various intracellular biochemical reactions, such as cell proliferation and stress response, and the overexpression of SAMS could allow cells to ithstand the abiotic stress and increase productivity. Compared to wild-type C. reinhardtii, recombinant cells overexpressing SAMS grew 1.56-fold faster and produced 1.51-fold more lipids in a nitrogen-depleted medium. Furthermore, under saline-stress conditions, the survival rate and lipid accumulation were 1.56 and 2.04 times higher in the SAMS-overexpressing strain, respectively. These results suggest that the overexpression of SAMS in recombinant C. reinhardtii has high potential in the industrial-scale production of biofuels and various other high-value-added materials.

• Nutritional Sciences
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• v.9 no.1
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• pp.48-54
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• 2006

Methods have been developed to evaluate the total antioxidant capacity of foods and plasma but limitations are associated with their ability to determine precisely the contribution of lipophilic antioxidants in a lipid milieu as well as interactions among them Thus, we modified the Oxygen Radical Absorbance Capacity (ORAC) assay to determine the peroxyradical scavenging ability of both hydrophilic and lipophilic compartments in plasma The hydrophilic ORAC assay was performed in a phosphate buffer system utilizing 2,2'-azobis (2-amidinopropane) dihydrochloride as a peroxyradical generator and fluorescein as the target The lipophilic ORAC assay was carried out in a dimethylsulfoxide :butyronitrile (DMSO/BN, 9:1 v/v) system using 2,2'-azobis (2,4-dimethyl valeronitrile) as a peroxyradical generator and BODIPY C11 581/591 as the target Analyses were conducted in bovine serum supplemented with water - and lipid - soluble antioxidants and in human plasma. Albumin (0.5$\sim$5 g/dL) and uric acid (0.1$\sim$0.5 $\mu$mol/L) increased hydrophilic ORAC values in a dose-dependent fashion ($R^{2}$=0.97 and 0.98, respectively) but had no impact on lipophilic ORAC values. $\alpha$-Tocopherol (15$\sim$200 $\mu$mol/L) increased lipophilic ORAC values in a dose-dependent fashion ($R^{2}$=0.94); neither $\alpha$-tocopherol nor $\beta$-carotene had an impact on hydrophilic ORAC values. However, addition of $\beta$-carotene at physiological concentration (0.23$\sim$1.86 $\mu$mol/L), either alone or in combination with other carotenoids, had no significant impact on lipophilic ORAC values. Thus, while assays of 'total antioxidant capacity' in biological matrices would be a useful research and clinical tool, existing methods are limited by the lack of complete responsiveness to the full range of dietary antioxidants.

• Natural Product Sciences
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• v.11 no.1
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• pp.22-26
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• 2005

Hygrophila auriculata (K. Schum.) Heine is a wild herb commonly found in moist places on the banks of tanks, ditches and paddy fields throughout India and is one of the main sources of Ayurvedic 'Rasayana' drug. The free radical scavenging potential of 50% aqueous alcoholic extract of H. auriculata (HAEt) was studied for DPPH scavenging activity, nitric oxide, hydroxyl radical and ferryl bipyridyl complex scavenging activity along with lipid peroxidation and total antioxidant capacity inhibition using Thiobarbituric acid reactive substances (TBARS) in rat liver homogenate. Integral antioxidative capacity was determined by photochemiluminescence assay. HAEt showed good radical scavenging activity at various concentrations $(200-1000\;{\mu}g/ml)$ against 1,1 diphenyl, 2-picrylhydrazyl (DPPH) (32.32-77.02%) with moderate scavenging activity against Nitric oxide (12.46-52.84%), hydroxyl radical (11.69-55.26%), ferryl bipyridyl complex (17.66-58.67%) and lipid peroxidation (0.829-0.416nmoles/mg protein). The above results indicate HAEt to be very effective antioxidant. It was suggested that the varied therapeutic activities claimed for the plant in the Indian indigenous systems of medicine may be in the part due to the free radical scavenging and/ or potent antioxidant activity.

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.53-62
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• 2007

Objective The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method Total antioxidant capacity (TAC), Total antioxidant response (TAR), Total phenolic content, Reactive oxygen species (ROS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities, lipid peroxidation were examined. Result Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. TAC and TAR of Puerariae Radix extract at the concentration of 5 mg/ml were 2.02 and 1.50 mM Trolox equivalents, respectively. Total phenolic content of Puerariae Radix extract at the concentration of 5 mg/ml was 2.29 mM gallic acid equivalent. Concentration of Puerariae Radix extract at which DPPH radical scavenging activity was inhibited by 50% was 5.91 mg/ml as compared to 100% by pyrogallol solution as a reference. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO4/ascorbic acid. Puerariae Radix extract at the concentration of 1 mg/ml slightly but significantly decreased TBARS concentration. The extract further prevented lipid peroxidation in a dose-dependent manner. The effect of Puerariae Radix extract on reactive oxygen species (ROS) generation was examined using cell-free system induced by hydrogen peroxide/FeSO4. Addition of 1 mg/ml of Puerariae Radix extract significantly reduced dichloroflurescein (DCF) fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Thus antioxidant effects of Puerariae Radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation. Conclusion As a result, Puerariae Radix seems to have antioxitative effect and antioxidant compount.

• Nutritional Sciences
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• v.7 no.1
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• pp.41-46
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• 2004

In postmenopausal women, the incidence of cardiovascular disease(CVD) is common and there is growing evidences that astaxanthin has a strong antioxidant capacity and plays a beneficial role in the prevention of CVD. However, current data are not sufficient to determine the effect of astaxanthin on improving lipid profiles and antioxidant capacity in human. In this study, 15 healthy postmenopausal women were divided into 3 groups and given astaxanthin supplements of 0,2 or 8mg/day for 8 weeks. Blood samples were taken before and after 4 and 8 weeks of astaxanthin supplementation for analysis of serum total choelsterol, LDL-cholesterol, HDL-cholesterol, triglyceride, plasma TBARS, total antioxidant status(TAS) and urinary 8-isoprostanes. HDL-cholesterollevels in 2mg and 8mg group increased significantly after 8 weeks from 50.6$\pm$5.8 to 60.4$\pm$7.1mg/dl, 44.4$\pm$10.7 to 49.4$\pm$2.7$mg/dl$ respectively (p<0.05). In the 2mg group, triglyceride decreased significantly from 171.6$\pm$67.4 mg/$dl$ to 145.8$\pm$5.1$mg/dl$ (p<0.05). Plasma TBARS level in the 2mg group decreased from 1.42$\pm$0.18nM/mg to 1.13$\pm$0.18nM/mg after 8 weeks (p<0.05). In the 8mg group, TBARS level decreased significantly from 1.62$\pm$0.14nM/mg to 1.13$\pm$0.12nM/mg after 8 weeks (p<0.05). TAS, as an indicator of lipid peroxidation, increased significantly from 0.85$\pm$0.42mM/$l$ to 1.90$\pm$0.58mM$l$ after 8 weeks in the 8mg group (p<0.05). Urinary 8-isoprostanes excretion did not decrease significantly with astaxanthin supplementation. In conclusion, it would be helpful for postmenopausal women with common cardiovascular disease to supplement with astaxanthin as an antioxidant.

• Nutrition Research and Practice
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• v.2 no.4
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• pp.295-300
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• 2008

Spirulina is a microscopic and filamentous cyanobacterium that contains essential amino acids, essential fatty acids, vitamins, minerals and anti-oxidative components. The purpose of this study was to examine effects of spirulina intervention in Korean patients with type 2 diabetes. The subjects were 37 type 2 diabetic patients who visited a diabetic clinic in Seoul and randomly assigned into spirulina (8 g/day) or control group. During the intervention period of 12 weeks, subjects were asked to keep usual diet and prohibited to take any functional foods or dietary supplements. Spirulina supplementation for 12 weeks did not affect anthropometric parameters, however, lowered plasma triglycerides level significantly (p<0.05). Spirulina supplementation also resulted in a significant reduction in plasma malondialdehyde level (p<0.05) and an increase in plasma adiponectin level (p<0.1). The lipid lowering effect of spirulina supplementation was different according to serum lipid levels of the subjects before entering the intervention. The subjects with higher initial triglyceride level showed higher reduction in plasma triglyceride and blood pressure. The subjects with higher initial total cholesterol and LDL-cholesterol level showed higher reduction in plasma concentrations of total cholesterol, LDL-cholesterol, IL-6, and blood pressure. It seems that spirulina supplementation is more effective in subjects with dyslipidemia. This study provides the evidence for beneficial effects of spirulina supplementation on blood lipid profiles, inflammatory variables, and antioxidant capacity in Korean patients with type 2 diabetes. The results suggest that spirulina is a promising agent as a functional food for diabetes management.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.145-149
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• 2005

This study was carried out to investigate the effect of dietary RVS on the WHC, color stability, and lipid oxidation of Hanwoo (Korean cattle) beef during cold storage after thawing, RVS fed Hanwoo (Korean cattle) beef was more effective in increasing WHC, color stability and delaying lipid oxidation than that without RVS in diet. And 4% RVS fed Hanwoo (Korean cattle) beef showed the greatest effects.

• Korean Journal of Poultry Science
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• v.45 no.2
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• pp.109-118
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• 2018

A great progress in genetic selection, nutrition and management practices has contributed to the improved growth rate of broilers and egg production in laying hens. For the increased productivity of modern poultry, a healthy chicken liver needs to cope with the increased metabolic demands. The liver is the major site of de novo fatty acid synthesis; therefore, hepatic lipogenesis is crucial for producing better quality meat and eggs. When de novo lipogenesis exceeds the capacity of lipid metabolism and secretion, large amounts of lipids accumulate in the liver of broilers, leading to a fatty liver. Upon onset of egg-laying in hens, lipids including free fatty acids, triglycerides, and phospholipids are dramatically increased in blood plasma for the synthesis of yolk precursors in oocytes. Productive hens with fatty liver often have hemorrhagic syndrome and sudden death due to the heavy demands of yolk synthesis, which burdens the liver. Understanding the lipid metabolism and hepatic lipid disorders is a key point in the improvement of the growth and production of chickens. This review focuses on the recent studies on lipid metabolism, the hepatic lipid disorders, and the prevention or reduction of fatty liver in poultry.