【作者】 曹雪珂； 李斌； 田静；

【Author】 Cao Xueke;Li Bin;Tian Jing;College of Food Science and Technology,Huazhong Agricultural University;

【机构】 华中农业大学食品科学技术学院；

【摘要】 魔芋葡甘聚糖(KGM)的体内抗逆性与其分子量和乙酰基改性的研究鲜有系统对比。本文研究了不同分子量及不同脱乙酰度的KGM对秀丽线虫的抗逆性和机体机能的影响。实验动物分别经过不同分子量及不同脱乙酰度的KGM孵育后,测定其在氧化应激和热应激下的存活率、产卵率和运动能力。结果表明,在KGM(654 ku)、KGM-1(435 ku)、KGM-2(212 ku)、KGM-3(124 ku)、KGM-4(94 ku)和KGM-5(67 ku)中,随着分子量的降低,显著延长氧化应激平均寿命的浓度明显降低。其中KGM-5的中高浓度可以分别延长31.0%和37.3%的平均寿命。热应激也呈现出一致的趋势,高浓度KGM原粉能显著延长28.1%的平均寿命,而KGM-5的中高浓度能分别延长36.7%和113.0%。产卵率和运动能力也呈现出相同的趋势。在0,7%,32%,46%和77%的脱乙酰度样本中,随着脱乙酰度的升高,KGM对氧化应激和热应激的抗性降低,高浓度的脱乙酰KGM促进了产卵率,运动能力没有受到负面影响。这些数据表明分子量和乙酰基对KGM的抗逆性有显著影响,其在衰老及衰老相关疾病的应用具有理论指导意义。更多还原

【Abstract】 The impact of KGM structures modification in molecular weights or deacetylation on the stress resistance in vivo has rarely been studied systematically.This research studied the effects of KGM with different molecular weights and different degrees of deacetylation on the stress resistance and physical fitness of Caenorhabditis elegans.After the nematodes were incubated with modified KGM,the survival rate of the nematodes under oxidative stress and heat stress,as well as the egg-laying rate and locomotion were measured.Among samples of KGM with molecular weights of 654 ku,435 ku,212 ku,124 ku,94 ku and 67 ku,upon with the decrease of molecular weights of KGM,the concentration that can significantly prolong the average lifespan of oxidative stress was significantly reduced.Among them,the medium and high concentrations of KGM-5 can extend the mean lifespan of nematodes by 31.0% and 37.3% respectively;A similar trend was also observed in heat-treated nematodes.KGM raw powder significantly prolonged lifespan under heat stress at high concentration by 28.1%,while the medium and high concentrations of KGM-5 prolonged 36.7% and 113.0% of mean lifespan of nematodes under heat stress respectively.Egg laying rates and locomotion showed similar trends.Among different degrees of deacetylation of 0,7%,32%,46% and 77%,upon with the increase of deacetylation degrees,the resistance of KGM to oxidative and heat stress gradually decreased.Meanwhile,the high concentration of KGM with different acetylation promoted egg laying rates;no impact on the locomotion of nematodes was observed.Taken together,molecular weight reduction or deacetylation of KGM had a significant impact on the stress resistance in vivo.These findings provided references for the further application of KGM in the research of ageing and ageing-related diseases.更多还原