Figure 5. Altered gut bacterial composition at the family levels. (A) Relative abundance at the family level in the different groups. (B) Red light exposure increased the abundance of Muribaculaceae in non-LPS-treated mice on day 3 relative to ambient white light or green light exposure. (C) The abundance of Lachnospiraceae was lower in mice exposed to red light than in those exposed to ambient white light or green light. (D) Red light exposure reduced the abundance of Ruminococcaceae in non-septic mice on day 3 relative to ambient white light or green light exposure, as well as in septic mice on day 3 relative to green light exposure. (E) Red light exposure reduced the abundance of Marinfilaceae relative to green light exposure in septic mice on day 3. (F) Red light exposure reduced Family-XIII on days 3 and 7 relative to ambient white light exposure. LPS administration increased the abundance of Family-XIII in mice exposed to red light. (G) Red light exposure reduced the abundance of Peptococcaceae in non-septic mice on days 3 and 7 relative to ambient white light exposure, as well as in septic mice on day 3 relative to green light exposure. Data are presented as the mean ± SEM (n = 6-7). **P < 0.01, ***P < 0.001, #P < 0.05, ##P < 0.01.