黑米花色苷的酰基化及产物对肠道菌群的益生作用

该研究以癸酸为酰基供体,对黑米矢车菊素-3-O-葡萄糖苷（C3G）酶法修饰。半制备型高效液相色谱（Semi-HPLC）用于纯化产物,质谱（MS）用于鉴定产物的结构。结果表明,酰化反应发生在C3G的葡萄糖苷上,单酰化产物为矢车菊素-3-O-(6”癸酰)葡萄糖苷（ACD）。通过体外模拟消化试验分析ACD在消化过程中的稳定性。并在体外发酵中,研究它对肠道菌群的调节作用及对短链脂肪酸（SCFAs）和乳酸产生的影响。结果表明,ACD在模拟唾液、胃和小肠液中几乎不被消化。体外发酵24 h后,ACD的总含量从96.83 mg/L降至23.20 mg/L。ACD显著增加了双歧杆菌属和阿里松氏菌属的相对丰度,降低了普氏菌属、小类杆菌属、巨单胞菌属和梭状芽孢杆菌属的相对丰度,而且促进了SCFAs的产生。它不仅对肠道菌群表现出比C3G更好的动态和多重调节作用,而且在促进SCFAs（乙酸、丙酸和丁酸）的产生方面表现出与菊粉相似的作用,为酰化花色苷作为益生元在食品中的应用提供理论依据。

Acylation of Anthocyanins from Black Rice and Probiotic Effect of the Product on Intestinal Microflor

In this study, cyanidin-3-O-glucoside (C3G) from black rice was enzymatically modified with capric acid as the acyl donor. Semi-preparative high performance liquid chromatography (Semi-HPLC) was used to purify the product, and mass spectrometry (MS) was used to identify the structure of the product. The results indicated that the acylation occurred to the glucoside of C3G, and the monoacylated product was cyanidin-3-O-(6" decanoyl) glucoside (ACD). The in vitro simulated digestion was used to examine the stabilityof ACD indigestion. Moreover, through in vitro fermentation, its regulation of intestinal microflora and effects on the production of short-chain fatty acids (SCFAs) and lactate were investigated. The results indicated that ACD was hardly digested in the simulated saliva, stomach and small intestinal fluid. After 24 h of in vitro fermentation, the total content of ACD decreased from 96.83 mg/L to 23.20 mg/L. ACD significantly increased the relative abundance of Bifidobacterium and Arisonia, decreased the relative abundance of Prevotella, Bacteroides, Macromonas and Clostridium, and promoted the production of SCFAs. It not only exhibited better dynamic and multiple regulatory effects on the intestinal microflora compared with C3G, but also exhibited similar effects to inulin in promoting the production of SCFAs (acetate, propionate, and butyrate), which provides a theoretical basis for the application of acylated anthocyanins as prebiotics in food.