Study on the interaction between β-carotene and gut microflora using an in vitro fermentation model

β -Carotene, a typical non-oxygenated carotenoid, is the most efficient source of retinol (VA). The low bio-availability of β -carotene lead to large accumulation in colon; however, the relationship between β -carotene and gut microflora remains unclear. This study intends to explore the interaction between β -carotene and gut microflora using an in vitro fermentation model. After 24 h fermentation, the degradation rate of β -carotene was (64.28 ± 6.23)%, which was 1.46 times that of the group without gut microflora. Meanwhile, the production of VA was nearly 2 times that of the group without gut microflora, indicating that the gut microflora can metabolize β -carotene into VA. β -Carotene also influences the production of short-chain fatty acids (SCFAs), the production of total SCFAs in 0.5 mg/mL β -carotene (BCM) group was (44.00 ± 1.16) mmol/L, which was 2.26 times that of the blank control (BLK) group. Among them, the production of acetic acid in BCM group was (19.06 ± 0.82) mmol/L, which was 2.64 time that of the BLK group. Furthermore, β -carotene significantly affected the structure and composition of gut microflora, increasing the abundance of Roseburia , Parasutterella and Lachnospiraceae, and decreasing the abundance of Dialister , Collinsella and Enterobacter ( P < 0.05). This study provides a new way to understand how β -carotene works in human body with gut microflora.