Development of specific and quantitative methods for the quality control of the polysaccharides from sea-tangle and sargassum / 中国天然药物

Polysaccharides from numerous traditional Chinese medicines have been proven as the bioactive ingredients and are hence used as the quality control markers. However, the assessment criteria always show a poor specificity, due to the lack of systematic comparison among the analogous herbs. In the present study, two similar materials, namely sea-tangle and sargassum, were selected as the model herbs to develop more specific methods for quality control. Two well-established methods, determination of the total polysaccharides content and monosaccharides composition analysis, were both employed. Based upon the quantitative results, the evaluation criteria of the polysaccharides contents of not less than 2.0% and 1.7% were proposed for sea-tangle and sargassum, respectively. Nine identical monosaccharide derivatives appeared on the HPLC chromatograms of the hydrolysis and derivatized solutions of the two drugs. Principal component analysis and orthogonal partial least squares discriminant analysis using the peak areas of monosaccharides derivatives as the variables were performed, and the results indicated that mannuronic acid and xylose with the opposite concentrations in the two drugs were the differential components. A discriminative criterion using the peak area ratio of these two monosaccharides derivatives was proposed for the qualitative identification. In conclusion, a more specific and quantitative quality control method was developed for sea-tangle and sargassum.

Effect of Glutathione With Sea Tangle Extract on Prevention of Selenite-Induced Cataract Formation in Rats

PURPOSE: To evaluate antioxidative and preventive effects of sea tangle extract on selenite-induced cataract formation. METHODS: Eighty SD rat pups were randomized into 8 groups. Group 1 received no injection of reagent (normal); Group 2 to 8 received injection of selenite (15 micromol/Kg, s.c.) was injected. In group 2 (control) and group 3, normal saline (i.p.) and ascorbic acid (i.p.) was injected on days 3~31. In groups 4~8, sea tangle extract (i.p.) was injected at a concentration of 12.5, 25, 50, 100, 200 mg/kg, respectively. Development of cataract was assessed and photographed weekly under slit lamp. Rat lenses were analyzed for antioxidant enzymes, glutathione peroxidase (GPx), superoxide dismutase and malondialdehyde. Furthermore, an amino acid analysis of sea tangle extract was performed. RESULTS: Significant differences (p<0.05) were seen in cataract development in group 7. Dense nuclear cataracts developed in 8 of 10 of the control group (group 2); Group 4~8 developed nuclear cataract with proportion of 6/10, 3/10, 2/10, 1/10, and 6/10 rats. In sea tangle injected group, levels of GPx were higher than in the ascorbic acid and control groups. In particular, group 7, injected with 100 mg/kg of sea tangle extract, showed significantly high level of enzyme. Results of the amino acid analysis showed sea tangle includes glutamate-glycine-cysteine, major constituents of glutathione (GSH). CONCLUSIONS: The glutamate-glycine-cysteine in sea tangle is supposed to increase the level of lens GSH and this may contribute to lowering cataract development. This study strongly supports the activity of sea tangle as an endogenous antioxidant and anticataract agent.

Evaluation of 8-week body weight control program including sea tangle (Laminaria japonica) supplementation in Korean female college students

This study was conducted to evaluate the effects of a body weight control program with supplementation of sea tangle (20 g/day) on 22 female college students. The contents of the program for 8 weeks contained diet therapy, exercise and behavioral modification through nutrition education. Body composition, dietary habit scores, serum lipid profiles, daily nutrient intakes and the quality of life were assessed at the beginning and at the end of the program. Average age of subjects and height were 20.8 years and 161.9 cm, respectively. After 8 weeks, there were significant reductions in body weight, body fat mass, percent body fat, waist-hip ratio and BMI. The dietary habit score such as a balanced diet, regularity of mealtime, overeating, eating while watching TV or using the computer and eating salty food were increased significantly. Serum lipid levels such as total cholesterol level, LDL-cholesterol level and triglyceride level were decreased but not significantly. There were decreases in intake of energy, protein and fat and increases in intakes of dietary fiber, folic acid, calcium and potassium from the beginning to the end of the program. There were significant improvements on subcomponents of quality of life; physical functioning, general-health and vitality. The limitation of this study was the fact that there was no control group, but an overall evaluation suggests the 8-week body weight control program consisting of diet therapy, exercise and behavioral modification with supplementation of sea tangle would be helpful to improve the body composition, dietary habits, daily nutrient intakes and quality of life in Korean female college students.

Hypoglycemic and Antioxidative Effects of Dietary Sea-Tangle Extracts Supplementation in Streptozotocin-Induced Diabetic Rats

The purpose of this study was to investigate the effect of dietary sea-tangle extracts on blood glucose levels, serum lipid levels, thiobarbituric acid reactive substance (TBARS) and glutathione enzymes in diabetic rats treated with streptozotocin (STZ) Four groups of rats (Sprague-Dawley male rats, 180 - 200g) were consisted of normal rats fed control diet (C), diabetic rats fed control diet (CD), normal rats fed sea-tangl extracts diet (E), and diabetic rats fed sea-tangle extracts diet (ED). Diabetes was induced by single injection of streptozotocin (60 mg/kg B.W.). After 7 weeks, rats were sacrificed, serum glucose, serum total cholesterol, triglyceride levels and glutathione enzymes were measured. Urine was significantly higher in CD and ED groups than those of others (p < 0.05). Levels of amylase, calcium, uric acid, hemoglobin, cholesterol and low density lipoprotein (LDL)-cholesterol were different among four groups. But high density cholesterol (HDL)-cholesterol of ED group was significantly higher (p < 0.05) than other groups (C and E group) And the weekly change of serum glucose was decreased in the 3th,4th and 5th weeks. But serum triglyceride (TG) of diabetic rats fed sea-tangle extracts diet (ED) was lower than diabetic rats fed control diet (CD). Activity of hepatic microsomal G6Pase was significantly increased CD and ED groups higher than C and E group, but kidney was decreased ED group. Hepateic glutathione S-transferase (GST) of CD and ED group were significantly lower than C and E group (p<0.05), glutathione peroxidase (GPX) of E and ED group were significantly higher than C and CD group (p<0.05), glutathione reductase (GR) activities of ED group was significantly lower than other groups, malondialdehyde (MDA) of ED was lower than E and CD group, but kidney was increased significant in ED group compared to liver. These results suggested that dietary sea-tangle extracts reduce .hepatic disorders such as oxidant than kidney. In conclusion, dietary sea-tangle extracts groups reduced blood TG and hepatic MDA levels in STZ-induced diabetic rats.