Anti-fatigue and Anti-hyperglycemic Activities of Two Konjac Polysaccharides

Objective:To study the effects of different doses of konjac glucomannan(KGM)and konjac glucomannan oligosaccharide(KOGM)on anti-fatigue and hypoglycemic activity in mice. Methods:A total of 35 Kunming male mice with no specific pathogen free(SPF)grade were randomly divided into a blank control group(administered with equal volume of normal saline)and a high dose group of konjac glucomannan(60 mg/kg),medium dose group(30 mg/kg),low dose group(15 mg/kg),and konjac glucomannan oligosaccharide high(60 mg/kg),medium(30 mg/kg),low(15 mg/kg)group. There were 7 groups in the dose group,5 mice in each group. The weight swimming test was used to record the exhaustive swimming time of mice,and the anti-oxidation activity of konjac glucomannan and its oligosaccharides was determined by measuring the biochemical indicators such as superoxide dismutase(SOD)and malondialdehyde(MDA). Another 40 mice were randomly divided into a blank control group(equal volume of normal saline),a positive control group(metformin hydrochloride 110.5 mg/kg)and konjac glucomannan and its oligosaccharide high,medium and low dose groups,8 groups of 5 mice each. Oral glucose tolerance test(OGTT)was used to measure the blood glucose levels of mice after oral glucose for 0,30,60,120 min,and effect of konjac glucomannan and its oligosaccharides on improving glucose tolerance were observed in normal mice. Results:In the anti-fatigue experiment,compared with the blank group,the doses of KGM and KOGM could prolong the weight-bearing swimming time of mice to some extent,increase the SOD activity in the liver of mice,reduce the MDA content,and the highest dose group was significant(p<0.05);in the glucose tolerance experiment,two different molecular weight polysaccharides had hypoglycemic effect,and the best effect was in the high dose group. Conclusion:Konjac glucomannan and its oligosaccharides had good anti-fatigue effects,and had good blood sugar lowering effect and improved glucose tolerance.