Abstract: Objective: To explore the effect of cinnamon oil on the enzyme activities involved in hepatic metabolism, the antioxidant capacity of liver, duodenum and colon tissues, and the intestinal flora in mice, and to evaluate the potential health benefits of consumption of cinnamon oil. Methods: Eight-week-old male C57 mice were randomly divided into three groups: control, low-dose (100 mg/(kg·d)) and high-dose (300 mg/(kg·d)) cinnamon oil groups. After 4 weeks of feeding, the body mass, the enzyme activities involved in liver metabolism and the antioxidant capacity of liver, duodenum and colon tissues were measured. Illumina high-throughput sequencing was used to measure the change in gut microbiota at the levels of phylum and genus, and gas chromatography-mass spectrometry was used to detect the change in the contents of short chain fatty acids (SCFAs) in the feces of mice. The results showed that consumption of cinnamon oil significantly reduced the abdominal fat index, and increased the liver alanine aminotransferase activity and the antioxidant capacity of intestinal tissue (P < 0.05). At the level of phylum, the relative abundance of Tenericutes in mouse feces was decreased significantly after consumption of cinnamon oil (P < 0.05). At the level of genus, the relative abundance of conditional pathogens such as Blautia and [Eubacterium]_fissicatena_group was decreased significantly (P < 0.05), while the relative abundance of probiotics such as Roseburia and Coprobacillus was increased significantly (P < 0.05). The contents of fecal acetic acid, propionic acid and total acid were decreased significantly in the high-dose cinnamon oil group (P < 0.05). These results showed that consumption of cinnamon oil could regulate redox balance and the structure of intestinal flora by inhibiting pathogenic bacteria and promoting the proliferation of beneficial bacteria, thus exerting potential health benefits.

Key words: cinnamon oil; antioxidant; intestinal flora; regulatory effect