Postbiotic from Bifidobacteria-Fermented Tomato Juice Alleviates Lipid Metabolism Disorders Caused by Microplastics

Microplastics (MPs) are widely distributed in the environment and can enter the human body via drinking water or inhaling MPs dust. Accumulation of MPs can lead to various health issues, including damage to the colonic mucosal barrier and liver damage. Consuming postbiotics may offer benefits such as reducing inflammation and enhancing immune response. However, there is limited research on whether the intake of postbiotics can mitigate the damage caused by MPs. Therefore, this study utilized a postbiotic derived from fermented tomato juice with a combination of <em>Bifidobacterium animalis</em> subsp. <em>lactis</em> H22B621, <em>Bifidobacterium bifidum</em> H22B664, and <em>Bifidobacterium longum</em> F58-9 to investigate their protective effects against MPs exposure in mice. Results showed that gavage with postbiotic from Bifidobacteria-fermented tomato juice could alleviate triglyceride (TG) accumulation in the liver by decreasing <em>Coriobacteriaceae bacterium</em> abundance and regulating octanoic acid synthesis. Meanwhile, after postbiotic gavage, beneficial bacteria in the gut increased, such as <em>Lachnospiraceae</em> <em>bacterium</em> A2 and <em>Duncaniella freteri</em>. In addition, serum alanine aminotransferase (ALT) levels significantly decreased, indicating that postbiotics could alleviate liver damage. Postbiotic treatment also alleviated colon barrier injury. This research provides evidence for the protective effect of postbiotics against the damage caused by MPs, further elucidates their mechanisms, and offers new perspectives on the development and utilization of probiotics.