Nsor-Atindana John, Zhou Ya Xing, Saqib Md Nazmus, Chen Maoshen, Douglas Goff H, Ma Jianguo, Zhong Fang
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, PR China; Department of Nutrition and Dietetics, University of Health Allied Sciences, Ho, Volta Region PMB 31, Ghana.
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, PR China.
Food Res Int. 2020 May;131:108935. doi: 10.1016/j.foodres.2019.108935. Epub 2019 Dec 23.
Cellulose is generally recognised as dietary fibre with no limit of permissible quantity in food, and its consumption may modulate digesta content and impact positively on the gastrointestinal physiology and gut microflora. However, cellulose in its native form possessed inherent undesirable physical properties, making it unattractive for food applications. Here, we postulate that by changing cellulose size to nanometric scale, its prebiotic effect would be altered and fermented differently in contrast with micro size cellulose by the gut microbiome and promote the yield of metabolites such as short chain fatty acids (SCFAs). Using faecal matter from three healthy human donors as microbial source, in vitro fermentation of variable size fractions of cellulose from the same were fermented under anaerobic conditions, and SCFAs as well Bifidobacterium selectively isolated and analysed. The increase in production of acetate (194%), butyrate (224%) and propionate (211%) after 24 h of fermentation was significantly promoted by the size reduction and revealed size-dependent relationship as exemplified R values >0.83. Consequently, gavaging rats with nanometric size cellulose (125 nm) significantly (p < 0.05) increased these SCFAs yields as well Bifidobacterium counts in contrast with both control and the micro scale size cellulose. Therefore, engineered nanocellulose might have beneficial physiological impact on the gut with improved prebiotic effect.
纤维素通常被认为是膳食纤维，在食品中的允许用量没有限制，其摄入可能会调节消化物成分，并对胃肠道生理和肠道微生物群产生积极影响。然而，天然形式的纤维素具有固有的不良物理性质，使其在食品应用中缺乏吸引力。在此，我们推测，通过将纤维素尺寸改变为纳米级，其益生元效应会发生改变，与微米级纤维素相比，肠道微生物群对其发酵方式也会不同，并能促进短链脂肪酸（SCFAs）等代谢产物的产生。以三名健康人类供体的粪便为微生物来源，将来自同一来源的不同尺寸级分的纤维素在厌氧条件下进行体外发酵，并对SCFAs以及选择性分离和分析的双歧杆菌进行检测。发酵24小时后，乙酸盐（194%）、丁酸盐（224%）和丙酸盐（211%）产量的增加因尺寸减小而得到显著促进，并呈现出尺寸依赖性关系，例如相关系数R值>0.83。因此，与对照组和微米级纤维素相比，用纳米级尺寸的纤维素（125纳米）灌喂大鼠显著（p<0.05）提高了这些SCFAs的产量以及双歧杆菌数量。因此，工程化纳米纤维素可能对肠道具有有益的生理影响，并具有改善的益生元效应。
