燕麦麸皮体外调节肥胖人群肠道微生物及抗氧化性

Oat Bran Regulates Gut Microbes and Antioxidant Properties in Obese People in Vitro

燕麦麸皮是燕麦加工过程中的副产品,含有丰富的膳食纤维、多酚等植物化学物质。通过模拟体外消化、发酵过程,评估不同剂量(1%,3%和5%)燕麦麸皮对肥胖人群粪便微生物群组成和短链脂肪酸、抗氧化的影响,结果表明:燕麦麸皮消化后,其抗氧化性显著提高(P<0.05)。微生物测定结果表明:在门水平上的主要优势菌为变形杆菌(29.01%~46.55%)、放线菌(7.82%~16.18%)、厚壁菌(44.63%~51.98%)及拟杆菌(0.05%~2.58%)。与对照组相比,添加燕麦麸皮后微生物α-多样性降低,厚壁菌和放线菌数量降低,说明燕麦麸皮具有抑菌作用。燕麦麸皮发酵后主要的短链脂肪酸为乙酸、丙酸和丁酸。总短链脂肪酸含量在FOB5组中含量为161.21μg/mL,显著低于其它各组(P<0.05)。结论:燕麦麸皮具有很好的抗氧化性,能够体外调节肠道微生物的丰度,降低短链脂肪酸含量,且呈剂量依赖性。本研究结果为燕麦麸皮减肥降脂机制提供了试验依据。

Oat bran is a by-product of oat,which is an excellent source of phytochemicals such as dietary fiber and polyphenols.Therefore,the aim of this study was to evaluate the effects of different levels(1%,3%and 5%)of oat bran on fecal microbiota composition,short-chain fatty acids and antioxidant capacity in an obese population,by simulating in vitro digestion and fermentation processes.The results showed that the antioxidant activity of oat bran was significantly increased after digestion(P<0.05)and the antioxidant activity was higher with increasing levels.The microbial results showed that the main dominant bacteria at the phylum level were Proteobacteria(29.01%-46.55%),Actinobacteria(7.82%-16.18%),Firmicutes(44.63%-51.98%)and Bacteroides(0.05%-2.58%).The microbialα-diversity decreased in the group with the addition of oat bran compared to the control group,as well as the number of Firmicutes and Actinobacteria,indicating that oat bran had an inhibitory effect.In addition,it was found that the main short chain fatty acids after oat bran fermentation were acetic acid,propionic acid and butyric acid.The total short chain fatty acid content in the FOB5 group was 161.21μg/mL,significantly lower than other groups.In conclusion,oat bran has good antioxidant properties.And it reduces the content of short-chain fatty acids by regulating the abundance of intestinal microorganisms.It is promising to provide a theoretical basis for the weight loss and lipid reduction mechanism of oat bran.