Clarke Sandra T, Brooks Stephen P J, Inglis G Douglas, Yanke L Jay, Green Judy, Petronella Nicholas, Ramdath D Dan, Bercik Premysl, Green-Johnson Julia M, Kalmokoff Martin
1Applied Bioscience Graduate Program, Faculty of Science,University of Ontario Institute of Technology,Oshawa,ON,Canada,L1H 7K4.
2Bureau of Nutrition Research,Health Canada,Ottawa,ON,Canada,K1A 0K9.
Br J Nutr. 2017 Sep;118(6):441-453. doi: 10.1017/S0007114517002318. Epub 2017 Sep 28.
Healthy adults (n 30) participated in a placebo-controlled, randomised, double-blinded, cross-over study consisting of two 28 d treatments (β2-1 fructan or maltodextrin; 3×5 g/d) separated by a 14-d washout. Subjects provided 1 d faecal collections at days 0 and 28 of each treatment. The ability of faecal bacteria to metabolise β2-1 fructan was common; eighty-seven species (thirty genera, and four phyla) were isolated using anaerobic medium containing β2-1 fructan as the sole carbohydrate source. β2-1 fructan altered the faecal community as determined through analysis of terminal restriction fragment length polymorphisms and 16S rRNA genes. Supplementation with β2-1 fructan reduced faecal community richness, and two patterns of community change were observed. In most subjects, β2-1 fructan reduced the content of phylotypes aligning within the Bacteroides, whereas increasing those aligning within bifidobacteria, Faecalibacterium and the family Lachnospiraceae. In the remaining subjects, supplementation increased the abundance of Bacteroidetes and to a lesser extent bifidobacteria, accompanied by decreases within the Faecalibacterium and family Lachnospiraceae. β2-1 Fructan had no impact on the metagenome or glycoside hydrolase profiles in faeces from four subjects. Few relationships were found between the faecal bacterial community and various host parameters; Bacteroidetes content correlated with faecal propionate, subjects whose faecal community contained higher Bacteroidetes produced more caproic acid independent of treatment, and subjects having lower faecal Bacteroidetes exhibited increased concentrations of serum lipopolysaccharide and lipopolysaccharide binding protein independent of treatment. We found no evidence to support a defined health benefit for the use of β2-1 fructans in healthy subjects.
健康成年人（n = 30）参与了一项安慰剂对照、随机、双盲、交叉研究，该研究包括两个为期28天的治疗期（β2-1果聚糖或麦芽糊精；3×5克/天），中间有14天的洗脱期。受试者在每种治疗的第0天和第28天提供1天的粪便样本。粪便细菌代谢β2-1果聚糖的能力很常见；使用以β2-1果聚糖作为唯一碳水化合物来源的厌氧培养基分离出了87种细菌（30个属和4个门）。通过末端限制性片段长度多态性分析和16S rRNA基因分析确定，β2-1果聚糖改变了粪便菌群。补充β2-1果聚糖降低了粪便菌群的丰富度，并观察到两种菌群变化模式。在大多数受试者中，β2-1果聚糖降低了拟杆菌门内系统发育型的含量，而增加了双歧杆菌属、粪杆菌属和毛螺菌科内系统发育型的含量。在其余受试者中，补充剂增加了拟杆菌门的丰度，双歧杆菌属的丰度增加程度较小，同时粪杆菌属和毛螺菌科的丰度降低。β2-1果聚糖对四名受试者粪便中的宏基因组或糖苷水解酶谱没有影响。在粪便细菌群落与各种宿主参数之间几乎没有发现相关性；拟杆菌门含量与粪便丙酸相关，粪便群落中拟杆菌门含量较高的受试者无论接受何种治疗都会产生更多己酸，而粪便拟杆菌门含量较低的受试者无论接受何种治疗血清脂多糖和脂多糖结合蛋白浓度都会升高。我们没有发现证据支持在健康受试者中使用β2-1果聚糖有明确的健康益处。
