As the high nutritional and functional values of quinoa acknowledged, the increasing researches focus on the bioactivities and related mechanisms of its abundant carbohydrates. Herein, the beneficial effects of the soluble polysaccharide fraction from quinoa was investigated to lower the serum lipid of rats treated by high-fat diet (HFD) and call the disordered gut microbiota back. The polysaccharide faction was firstly extracted by ultrasonic-assisted extraction technology (yield of 9.65%) and characterized of the monosaccharide composition with glucose and arabinose (1.17:1, molar ratio). And then, the oral administration of quinoa polysaccharide of 300 mg·kg⁻¹·day⁻¹ and 600 mg·kg⁻¹·day⁻¹ for 8 weeks remarkably alleviated dyslipidemia by decreasing the levels of serum total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), malondialdehyde (MDA), total glutamic pyruvic transaminase (ALT) and glutamic oxaloacetic transaminase (AST) in rats fed with HFD, as well as the reduced hepatic lipid accumulation. Meanwhile, the relative abundance of gut microbiota could be disordered by the long term of HFD. Nevertheless, dietary supplementation of quinoa polysaccharide could enhance species richness and regulate the gut microbiota community structure, reducing the ratio of Firmicutes and Bacteroides, the relative abundance of Proteobacteria. Meanwhile, Sequencing of 16S rRNA gene revealed that intake of quinoa polysaccharide decreased the relative abundances of Desulfovibrio and Allobaculum, which were positively correlated with serum lipid profiles and beneficial to lessen intestinal inflammation. Taken together, the present study demonstrated that quinoa polysaccharide supplementation could ameliorate the hyperlipidemia induced by HFD in association with modulating gut microbiota in a positive way.

藜麦具有很高的营养价值和功能价值，因此越来越多的研究集中在其丰富的碳水化合物的生物活性及其相关机理上。在本文中，研究了藜麦中可溶性多糖成分对降低高脂饮食（HFD）处理的大鼠的血脂并将其称为失调的肠道菌群的有益作用。首先通过超声辅助提取技术提取多糖成分（收率为9.65％），并表征了具有葡萄糖和阿拉伯糖的单糖组成（摩尔比为1.17：1）。然后，口服给予300mg·kg ^-1 ·天^-1和600mg·kg ^-1 ·天^-1的藜麦多糖。降低大鼠血清总甘油三酸酯（TG），低密度脂蛋白胆固醇（LDL-C），丙二醛（MDA），总谷氨酸丙酮酸转氨酶（ALT）和谷氨酸草酰乙酸转氨酶（AST）的水平可显着缓解血脂异常8周HFD以及降低的肝脂质蓄积。同时，长期的HFD可能会扰乱肠道菌群的相对丰度。然而，藜多糖的日粮中添加能提高物种丰富度和调节肠道菌群群落结构，减少的比例厚壁菌门和拟杆菌的相对丰度蛋白菌。同时，对16S rRNA基因的测序表明，摄入藜麦多糖降低了Desulfovibrio和Allobaculum的相对丰度，这与血清脂质谱呈正相关，有利于减轻肠道炎症。综上所述，本研究表明，藜麦多糖的补充可以改善HFD所致的高脂血症，并以积极的方式调节肠道菌群。