亚麻籽粉摄入对健康成年人肠道菌群结构的影响

肠道是人体内代谢的重要场所，肠道内寄居的大量细菌在代谢过程中起到至关重要的作用。亚麻籽富含人体必需不饱和脂肪酸、膳食纤维、木酚素等多种营养成分，具有预防心脑血管疾病、改善肠功能、调节雌激素等功效。本实验旨在探究亚麻籽对人体肠道菌群的影响。通过招募健康成年志愿者，进行为期21 d的亚麻籽饮食干预（亚麻籽摄入量为0.6 g/（kg·d）），收集亚麻籽摄入前后健康成年人粪便样品，进行16S rRNA高通量测序和高通量气相色谱分析。结果显示，志愿者在摄入亚麻籽后，肠道微生物多样性指标Shannon指数升高，同时肥胖群体中高比例厚壁菌门的占比下调，所有粪便样本中短链脂肪酸含量上升。本研究证明，亚麻籽的摄入可以改变健康成年人肠道菌群结构，增加肠道微生物菌群多样性，同时可以促进肠道内短链脂肪酸的产生，从而维持肠道微环境，抑制肠道疾病的发生；并且其部分菌群结构的改变可能有利于预防肥胖症的风险。

Effect of Dietary Flaxseed Powder on Intestinal Flora Structure in Healthy Adults

The intestine is an important organ for metabolism in the human body. It is home to a large number of bacteria that play a vital role in the metabolic process. Flaxseed is rich in essential fatty acids, dietary fiber, lignans and other nutrients, and it has the function of preventing cardiovascular and cerebrovascular diseases, improving intestinal function, and regulating estrogen levels and so on. In order to explore the effect of ingestion of flaxseed on the human intestinal flora, healthy adult volunteers were recruited for receiving dietary intervention with flaxseed (0.6 g/(kg·d)) for 21 d. We collected fecal samples at the before and after the experimental period for high-throughput 16S rRNA gene sequencing and high-throughput gas chromatography analysis. The data showed that the intestinal microbial diversity (Shannon index) was increased after the intake of flaxseed, while the proportion of the dominant bacteria of Firmicutes in obese populations was down-regulated, and the content of short-chain fatty acids in all fecal samples was increased. This experiment proved that the intake of flaxseed could change the intestinal microflora structure of healthy adults, increase the intestinal microbial diversity, and promote the production of short-chain fatty acids (SCFA) in intestine, maintaining the intestinal microenvironment and preventing intestinal diseases. In additional, some changes in the structure of the intestinal microflora may be beneficial to prevent the risk of obesity.