Isolation and Characterization of Effective Bacteria That Reduce Ammonia Emission from Livestock Manure

Abstract

Ammonia from livestock manure reacts with chemical components discharged from various emission sources to produce airborne particulate matter. This study aimed to investigate a novel effective microbial agent to suppress ammonia gas emitted from manure. Both isolated L12I and 12III strains, identified as Pediococcus acidilactici (PA), were selected for their superior activity in assays performed with the evaluation criteria such as acid production, ammonia decomposition, and urease inhibition, which are key factors influencing ammonia excretion. The survivability of PA strains was confirmed by an increase in DNA abundance in the manure. PA strains lowered the pH of manure and suppressed the growth of hyper-ammonia-producing bacteria (HAB) possessing urease activity. The L12I and 12III treatment groups showed 23.58% and 38.00% emission reductions, respectively. Especially, the 12III strain was proven to be the more effective strain for reducing ammonia gas emission, with the best ability to reduce pH and inhibit HAB. The strains could have an additive effect in improving the manure quality as a nitrogen fertilizer by preserving the total nitrogen and urea content. These results suggest that PA strains can be used as unprecedented microbial agents to improve manure-derived environmental pollution and improve fertilizer quality.