Biodegradation of ethanol and acetaldehyde by Lactiplantibacillus plantarum YDL-01 from healthy human feces.

Excessive alcohol intake triggers a series of systemic health hazards through the accumulation of acetaldehyde, a major carcinogen that poses a severe threat to human health. Here, a promising probiotic bacterial strain capable of biodegrading both ethanol and acetaldehyde was successfully isolated from healthy human feces and identified as Lactiplantibacillus plantarum YDL-01. In vitro assays demonstrated that an initial concentration of 5.0 g/L of ethanol or acetaldehyde could be completely biodegraded within 72 h or 16 h, respectively, by whole cells or cell-free extracts (CEs) of YDL-01, indicating that YDL-01 possesses a strong capacity for the biodegradation of both compounds. Whole-genome sequencing revealed the key genes responsible for alcohol metabolism in YDL-01, elucidating a complete catabolic pathway: ethanol is initially converted to acetaldehyde, catalyzed by alcohol dehydrogenase (ADH, EC 1.1.1.1), and acetaldehyde is further transformed into acetic acid via aldehyde dehydrogenase (ALDH, EC 1.2.1.10). In vitro safety assessments confirmed that YDL-01 exhibits no hemolytic activity and lacks amino acid decarboxylase activities, preliminarily verifying its biosafety, which is critical for the development of functional foods or biotherapeutic products for ethanol and acetaldehyde detoxification.