Exploring enzymatically active bacterial diversity in decomposing cow manure: insights into biodegradation dynamics within the initial mesophilic phase

This study investigated the isolation and characterization of bacterial strains with enzymatic potential from cow manure undergoing a 6-day decomposition process (initial mesophilic heating). A total of 270 bacterial isolates were obtained, with 48 isolates exhibited ligninase, amylase, protease, lipase, cellulase, and xylanase activity. Morphological, biochemical and molecular characterization classified them into nine species. The enzymatic analysis revealed that Bacillus licheniformis exhibited the highest enzymatic activity for ligninase, lipase, and amylase, recording 1.13, 9.92, and 8.1 U/mL, respectively, compared to other bacterial species. Furthermore, B. subtilis exhibited the highest enzymatic activity for protease, xylanase, and cellulase, recording 3.33, 1.96, and 0.5 U/mL, respectively. Our study reported Acetobacter tropicalis and A. pasteurianus with enzymatic activity for lipase and amylase. We also identified Lactiplantibacillus plantarum with enzymatic activity for ligninase and xylanase, and Lacticaseibacillus casei with enzymatic activity for ligninase, cellulase, and xylanase. Additionally, we reported Lentilactobacillus buchneri with enzymatic activity for ligninase, amylase, protease, lipase, cellulase, and xylanase. Furthermore, our study identified Cereibacter sphaeroides with enzymatic activity for cellulase, xylanase, protease, and ligninase, and Streptomyces albidoflavus with enzymatic activity for ligninase. These findings expand the understanding of bacterial enzymatic capabilities with potential in biotechnology, waste degradation, and industrial enzyme production.

Graphical abstract