Impacts of ammoniacal odour removal bioagent on air bacterial community.

While biotechnologies offer eco-friendly solutions for eliminating air contaminants, there is a scarcity of research examining the impacts of microbial purification of air pollutants on the structure and function of air microbial communities. In this study, we explored a Lactobacillus paracasei B1 (LAB) agent for removing ammoniacal odour. The impacts of LAB on air bacterial community were revealed. by analyzing the air samples before (BT) and after (AT) LAB bioagent treatment. Remarkably, the LAB bioagent significantly reduced the air ammonia concentration by 96.8%. This reduction was associated with a notable decline in bacterial diversity and a significant shift in community composition. The relative abundance of Staphylococcus, a common pathogen, plummeted from 1.91% to 0.03%. Moreover, other potential pathogens decreased by over 87%, signifying the bioagent's impactful role in diminishing health risks. The dominance of OTU-4 (Lactobacillus) highlighted its crucial role not only in competitive interactions but also potentially in shaping the metabolic pathways or community dynamics within the treated air microbial ecosystem. This shift towards deterministic assembly processes post-treatment, as highlighted by the normalized stochasticity ratio (NST), sheds light on the underlying mechanisms dictating the microbial community's response to bioagent interventions. The bioagent-purified air microbial community showed a strong preference for variable selection (88.9%), likely due to the acidity generated by the LAB. In conclusion, our findings emphasized the positive impact of LAB bioagent in enhancing air quality, which associated with the changes in microbial community.