Porphyra tenera (PT) is a functional seaweed food that has been reported for health benefits such as antioxidant, immunostimulant, anti-inflammation, and hepatoprotective effects. In this study, we investigated the effect of PT extracts on gut microbiota modulation in colitis-induced mice. The mice experiment was designed as three groups including normal mice (CTL), dextran sodium sulfate (DSS)-fed mice, and DSS plus PT extracts-fed mice (PTE). DSS was administrated through drinking water containing DSS for 1 week, and the PT extract was ingested into the gastrointestinal tract in mice. PT extract ameliorated the decreased body weight and colon length and improved disease activity index and pro-inflammatory cytokine expression. In addition, PT extract significantly shifted the gut microbiota of mice. DSS treatment significantly increased the portion of harmful bacteria (i.e., Helicobacter, Mucipirillum, and Parasutterella) and decreased the butyrate producing bacteria (i.e., Acetatifactor, Alistipes, Oscillibacter, and Clostridium_XIVb). PT extract increased the abundance of genera Clostridium_XIVb and also enriched some of predicted metabolic activities such as glyoxylate cycle, ethylmalonyl-CoA pathway, nitrate reduction, creatinine degradation, and glycine betaine metabolism. These results suggest that PT extract may ameliorate the DSS-induced colitis inflammation through regulating the compositions and functions of gut microbiota in mice.

中文翻译：

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硫酸葡聚糖硫酸钠诱导的结肠炎小鼠紫菜提取物的抗炎特性和肠道菌群调控

紫菜（PT）是一种功能性海藻食品，据报道对健康有益，例如抗氧化剂，免疫刺激剂，抗发炎和保肝作用。在这项研究中，我们调查了PT提取物对结肠炎诱发小鼠肠道微生物群调节的影响。将小鼠实验设计为三组，包括正常小鼠（CTL），葡聚糖硫酸钠（DSS）喂养的小鼠和DSS加PT提取物喂养的小鼠（PTE）。通过含有DSS的饮用水给予DSS 1周，并将PT提取物摄入小鼠的胃肠道。PT提取物改善了体重和结肠长度，并改善了疾病活动指数和促炎细胞因子的表达。此外，PT提取物显着改变了小鼠的肠道菌群。Helicobacter，Mucipirillum和Parasutterella），并降低了产生丁酸盐的细菌（即，乙酰乙酸杆菌，阿利斯贝贝菌，Oscillibacter和Clostridium_XIVb）。PT提取物增加了梭状芽胞杆菌（Clostridium_XIVb）属的丰度，还丰富了一些预测的代谢活性，例如乙醛酸循环，乙基丙二酰辅酶A途径，硝酸盐还原，肌酸酐降解和甘氨酸甜菜碱代谢。这些结果表明PT提取物可通过调节小鼠肠道菌群的组成和功能来改善DSS诱导的结肠炎。