Effect of Processing on Residual Buprofezin Levels in Ginseng Products.

This study determined residual buprofezin levels in fresh ginseng and evaluated their changes during processing. Supervised field trials were conducted at Yeongju, Geumsan, and Goesan, Korea. Buprofezin 12.5% EC was applied to 5-y ginseng in accordance with the Korean good agriculture practice (GAP). Samples were collected at 0, 7, 14, 21, and 30 d after the final application. On day 14 (GAP-equivalent preharvest date), the ginseng was processed to obtain dried and red ginseng. The average buprofezin concentrations on day 0 were 0.076 (Yeongju), 0.055 (Geumsan), and 0.078 mg kg-1 (Goesan). Residual concentrations increased as ginseng was processed into dried and red ginseng. Residue levels in dried ginseng manufactured by hot air drying were higher than in red ginseng obtained by steaming, hot air, and sunlight drying. However, the absolute amount of pesticides decreased by approximately 20-30% as a result of calculating the reduction factor considering the dry yield and moisture content. Therefore, the residual concentration in processed products may vary depending on the processing method, and it is deemed necessary to consider the processing yield and moisture content when evaluating the safety of residual pesticides in dried processed products.

Characteristics of phosphorus adsorption for a titanium mesostructure synthesized with various surfactants.

Eutrophication due to excessive phosphorus in water has been considered one of the most important environmental problems. In this study, a titanium mesostructure, prepared with different surfactant templates, was tested to confirm its applicability as an adsorbent for the removal of phosphorus and to evaluate the phosphorus removal efficiency. An X-ray diffraction analysis, the phosphorus adsorption isotherm and a kinetic test were performed on the titanium mesostructure synthesized with various molar ratios of base material to surfactant and different surfactant templates. It was revealed that the mesostructure synthesized with the molar ratio of 1.00/0.25 was the most uniformly and clearly formed and had the maximum adsorption capacity.

Beneficial effect of chungkukjang on regulating blood glucose and pancreatic beta-cell functions in C75BL/KsJ-db/db mice.

The current study investigated the antidiabetic effect of chungkukjang, a widely used traditional Korean soybean fermentation food, in a type 2 diabetic animal model, C57BL/KsJ-db/db mice. After a 2-week acclimation period, the db/db mice (male, 5 weeks old) were divided into three groups: diabetic control (AIN-76 diet), chungkukjang (5 g/100 g of diet), and rosiglitazone (0.005 g/100 g of diet). The supplementation of chungkukjang induced a significant reduction of blood glucose and glycosylated hemoglobin level, and it improved insulin tolerance compared to the diabetic control group. Plasma and pancreatic insulin levels of the chungkukjang-supplemented group were significantly higher than those of the diabetic control mice, and the plasma glucagon level was also significantly different. The supplementation of chungkukjang and rosiglitazone significantly elevated hepatic glucokinase activity with a simultaneous reduction of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activity in the db/db mice compared to the diabetic control mice. In addition, the chungkukjang-supplemented group had an increased hepatic glycogen content compared to the diabetic control and rosiglitazone-supplemented groups. Consequently, these results suggest that chungkukjang may be beneficial in improving insulin resistance and hyperglycemia in type 2 diabetic animals that are partly medicated by the regulation of hepatic glucose enzymes and insulin sensitivity in peripheral tissues.

Hypocholesterolemic and antioxidant properties of 3-(4-hydroxyl)propanoic acid derivatives in high-cholesterol fed rats.

The purpose of the present study was to evaluate the in vivo efficacy of two cinnamic acid synthetic derivatives (allyl 3-[4-hydroxyphenyl]propanoate; HPP304, 1-naphthyl-methyl 3-[4-hydroxyphenyl]propanoate; HPP305) in high-cholesterol fed rats and compare their actions to that of cinnamic acid. Cinnamic acid and its synthetic derivatives were supplemented with a high-cholesterol diet for 42 days at a dose of 0.135 mmol/100g of diet. The supplementation of HPP304 and HPP305 significantly lowered cholesterol and triglyceride levels in the plasma and liver with a simultaneous increase in the HDL-cholesterol concentration, whereas cinnamic acid only lowered the plasma cholesterol concentration. Cinnamic acid lowered hepatic HMG-CoA reductase activity in high-cholesterol fed rats, however, its synthetic derivatives (HPP304 and HPP305) did not affect HMG-CoA reductase activity compared to the control group. Instead, the HPP304 and HPP305 supplements significantly lowered hepatic acyl coenzyme A:cholesterol acyltransferase activity and increased the fecal bile acid. The SOD activity of the erythrocytes and liver was not different between the groups, however, the activities of CAT and GSH-Px, and the level of GSH in the erythrocytes were significantly higher in the HPP304 and HPP305 groups than in the control group. On the other hand, the activities of CAT and GSH-Px, and the level of malondialdehyde in the liver were significantly lower in the HPP304 and HPP305 groups. The antioxidant activities of these cinnamic acid synthetic derivatives were similar to the cinnamic acid in the high-cholesterol fed rats. In addition, HPP304 and HPP305 lowered amniotransferase activity in the plasma. These results suggest that two cinnamic acid synthetic derivatives (HPP304 and HPP305) exert lipid-lowering action and antioxidant properties without hepatotoxicity in high-cholesterol fed rats.

Eucommia ulmoides Oliver leaf extract increases endogenous antioxidant activity in type 2 diabetic mice.

Eucommia ulmoides Oliver (Du-zhong) leaf extract was investigated for its antioxidant effects in type 2 diabetic animals, C57BL/KsJ-db/db mice. Du-zhong extract equivalent to 1% dried whole Du-zhong leaf (0.187 g of extract/100 g of diet) was added to the experimental diets for 6 weeks. The Du-zhong extract supplement significantly lowered blood glucose concentrations and elevated plasma paraoxonase activity compared with the control group. The activities of erythrocyte superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were significantly higher in the Du-zhong group compared with the control group, while glutathione reductase (GR) activity was not different between groups. The activities of SOD, GSH-Px, and GR in liver and kidney were not affected by Du-zhong extract supplementation, whereas the CAT activity was significantly higher in the Du-zhong group than in the control group. Du-zhong extract supplementation resulted in lower levels of hydrogen peroxide and lipid peroxide in erythrocytes, liver, and kidney. These results suggest that the antioxidant activity of Du-zhong extract is potentially beneficial for the prevention and management of complications of type 2 diabetes.

Naringin time-dependently lowers hepatic cholesterol biosynthesis and plasma cholesterol in rats fed high-fat and high-cholesterol diet.

The flavonoid naringin was investigated for its differential effects on hepatic cholesterol regulation when supplemented for 3 weeks and 6 weeks. Sprague-Dawley rats were fed a high-fat and high-cholesterol diet with or without 0.02% naringin supplement for 3 or 6 weeks. Supplementation with naringin resulted in a significant decrease in the plasma cholesterol and triglyceride concentrations in the 6-week trial. Although high-density lipoprotein (HDL)-cholesterol was not altered in either trial, the HDL-cholesterol/total cholesterol ratio (in percent) was significantly higher, and the atherogenic index was significantly lower in the naringin-supplemented groups in the 6-week trial. The hepatic cholesterol content was also lowered by naringin supplementation only in the 6-week trial. The hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity was lower in the rats supplemented with naringin for 6 weeks, while the hepatic acyl-coenzyme A:cholesterol acyltransferase activity was lower in both the 3-week and 6-week trials. Results indicate that supplementation with naringin for 3 weeks did not exhibit a hypolipidemic effect when given with a HFHC diet. Naringin can, however, be beneficial for lowering hepatic cholesterol biosynthesis and levels of plasma lipids when supplemented for 6 weeks in this animal model.