Institute of Agro-product Processing, Jiangsu Academy of Agricultural Sciences, 50 Zhongling Street, Nanjing 210014, China.
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.
Food Funct. 2022 Jan 4;13(1):170-185. doi: 10.1039/d1fo02012a.
In this work, holocellulose nanocrystals (CNCs) were isolated from burdock insoluble dietary fiber (IDF) by enzymatic hydrolysis and ultrasonic treatment and their inhibitory effects against α-amylase and α-glucosidase were investigated. The hydrodynamic diameter of CNCs decreased from about 600 to 200 nm with increasing sonication time, accompanied by an improvement in cellulose and glucose contents. Steady-state fluorescence studies suggested that static complexes were formed between CNCs and α-amylase or α-glucosidase a spontaneous and endothermic approach, which was driven by both hydrophobic interactions and hydrogen bonding. The median inhibitory concentration (IC) values of CNCs against the tested enzymes were positively correlated with their size, and non-competitive and mixed types of inhibition were detected using the Lineweaver-Burk plots. During the simulated digestion, the inclusion of burdock CNCs obviously retarded the starch hydrolysis in both dose- and size-dependent manners, suggesting their potential in blocking the postprandial serum glucose upsurge.
在这项工作中，通过酶解和超声处理从牛蒡不溶性膳食纤维（IDF）中分离出了全纤维素纳米晶体（CNC），并研究了其对α-淀粉酶和α-葡萄糖苷酶的抑制作用。随着超声时间的增加，CNC 的水动力学直径从约 600nm 减小到 200nm，同时纤维素和葡萄糖含量也有所提高。稳态荧光研究表明，CNC 与α-淀粉酶或α-葡萄糖苷酶之间形成了静态复合物，这是一个自发的、吸热的过程，由疏水相互作用和氢键驱动。CNC 对测试酶的半数抑制浓度（IC）值与其大小呈正相关，通过 Lineweaver-Burk 图检测到非竞争性和混合性抑制类型。在模拟消化过程中，牛蒡 CNC 的加入以剂量和尺寸依赖的方式明显延缓了淀粉的水解，这表明它们有可能阻止餐后血清葡萄糖的飙升。
