小米和燕麦中水溶性膳食纤维结构表征及对体外发酵体系短链脂肪酸的影响

Structure and short chain fatty acids produced characteristics by in vitro fermentation of water soluble dietary fibers isolated from millet and oats

利用酶解的方法提取黄小米和燕麦中水溶性膳食纤维,并利用红外光谱和高效液相色谱技术分别对其官能团结构及单糖组成进行表征;通过模拟人体肠道消化系统环境,对添加不同浓度的膳食纤维发酵体系进行短链脂肪酸含量测定,观察不同浓度及不同发酵时间对体外发酵液中短链脂肪酸的影响。研究表明黄小米和燕麦中水溶性膳食纤维具有多糖特征官能团,组成黄小米和燕麦中水溶性膳食纤维的单糖为鼠李糖、阿拉伯糖、葡萄糖和半乳糖;人体粪便提取物中的微生物可以代谢黄小米和燕麦中水溶性膳食纤维产生甲酸、乙酸、丙酸和丁酸,当向发酵体系中添加水溶性膳食纤维时,随着发酵时间的延长,短链脂肪酸的含量逐渐增加;同时随着添加膳食纤维的浓度的增加,短链脂肪酸的含量也逐渐增加。儿童粪便提取物发酵体系产生的短链脂肪酸浓度要高于成人粪便提取物发酵体系产生的短链脂肪酸浓度。

Using enzymatic hydrolysis method to extracted water soluble dietary fibers of yellow millet and oats, and using infrared spectroscopy and high performance liquid chromatography equipment to analysis the structure of functional groups and monosaccharide composition. Meanwhile, we were analysis the content of short chain fatty acids of the systems by simulating the human digestive system environment. The results showed that： the water soluble dietary fibers of yellow millet and oats had characteristic functional groups of polysaccharide, and monosaccharide compositions mainly containing glucose, galactose, rhamnos and arabinose; Human fecal microbes could metabolic the water soluble dietary fibers from yellow millet and oats and produced formic acid, acetic acid, propionic acid and butyric acid, when added water soluble dietary fibers to the fermentation system, with the extension of fermentation time, the content of short chain fatty acids were gradually increased; the content of short chain fatty acids also gradually increased when increased with the addition of concentrations of dietary fibers. The short chain fatty acids produced by the fermentation of the children＇s fecal extract is higher than the concentration of short chain fatty acids produced by the fermentation of the adult fecal extract.