This study tested the anti-obesity and hypolipidemic effects of red garlic extract in obese rats induced by a high fat diet over a period of 4 weeks. Red garlic extract of 15 brix was added in 1, 3, 5 and 7% ratios in diets. The obesity index and body fat content significantly decreased in rats fed a diet with over 3% red garlic extract compared to the control group. There was no significant difference in weight of visceral and epididymal fat in rats fed red garlic extract. Total lipid and triglyceride levels in serum were significantly decreased in a dose-dependent manner, and AI and CRF also fell. ALT and AST activities in groups fed red garlic extract were decreased compared to the control group. Total lipid level in liver tissue of the groups fed 5-7% red garlic extract exhibited a significant decrease compared to the control group. Total cholesterol and triglyceride levels in feces were significantly increased in rats fed a diet with over 5% red garlic extract. Lipid peroxide levels were significantly decreased in the groups fed diets with 5-7% red garlic and antioxidant activity in serum was significantly increased in the group fed a diet with 7% red garlic extract compared to the control group. Our results suggest that red garlic extract could have anti-obesity and hypolipidemic effects for suppressing obesity index and decreasing lipid profiles.
IntroductionAs the choice for a high-calorie and high-fat diet increases due to the economic stability and affluence, so does the occurrence of metabolic disease caused by over-weight [27]. Obesity is the condition under which surplus energy is accumulated as lipids, which is attributable to the increase of energy intake and the decrease of consumption. From the balance is lost, obesity or hyperlipidemia develops, leading to a serious disease. In Korea, the social and economic cost incurred by the increase of obese population rises annually. Given that 40% of people who die by circulating system disease including atherosclerosis, cerebro-, cardio-vascular complications, hypertention, diabetes and functional depression of certain organs are obese, it is necessary to take a fundamental measure to improve the situation [47].Although the drug therapy proved to be effective as a behavior correction therapy used for the control of lipid metabolism in obese, it accompanies side-effects such as headaches, insomnia, and vomiting [29]. Thus, there is a growing attention on the way to improve obesity using phyto-nutrient that does not cause side-effects, among which garlic is known to effective for the control of lipid metabolism and obesity [1,16,24,31,51]. A major bioactive substances of garlic (Allium sativum L.) are an organic sulfur compounds containing allicin [11,18,22], which has the cardioprotective function among others [25]. Reportedly in Korea, the bioactive effect is elevated through the heat-treatment which turns fresh garlic into aged black garlic [22,46] supplemented with 5% red garlic extract, RG-7: supplemented with 7% red garlic extract. production of t...