Objective The effects of Chlorella pyrenoidosa on antioxidant and intestinal bacterial in mice were analyzed.

Method Fifty sparse-fur(SPF)mice were randomly divided into normal group(equal volume of normal saline, CK1), VE group(100 mg/kg, CK2), and different doses of C. pyrenoidosa(100 mg/kg, 200 mg/kg, 300 mg/kg), respectively.After 3 weeks, the total antioxidant capacity(T-AOC)and superoxide dismutase(SOD) activity in serum and liver homogenates of mice were measured. Moreover, the DNA in mouse feces were exacted, and community structure diversity of intestinal bacteria was analyzed by using high-throughput sequencing technology.

Result It was found that the activity of T-AOC and SOD in serum and liver of mice treated with different doses of C. pyrenoidosa were significantly higher than that of normal group. High-throughput sequencing results showed that the structures of mice intestinal bacteria were dominated by Bacteroides and Firmicutes. Compared with normal group, there was no significantly difference in the Alpha diversity indexes (Shannon, Simpson, Chao1 and Coverage)of intestinal bacteria treated with C. pyrenoidosa. The results of PCA analysis indicated that there was significant difference in intestinal bacteria of mice between treatment with C. pyrenoidosa and normal group. Compared with normal group, the abundance of Bacteroides and Lactobacillus significantly increased in mice treated with C. pyrenoidosa, while the abundance of Muribaculum significantly decreased.

Conclusion C. pyrenoidosa could increase the antioxidant activity, regulate abundance of beneficial bacteria in intestinal tract, and improve intestinal environment of mice.