Curr Microbiol. 2026 Aug 12;83(10):510. doi: 10.1007/s00284-026-05091-x.
ABSTRACT
Laccase, with its wide substrate range, has significant potential in industrial biocatalysis, where agricultural waste has attracted considerable interest as an economical and sustainable alternative as a low-cost source for enzyme production. In this study, the effect of various factors (different aromatic compounds, carbon and nitrogen nutrient sources, metal ions, pH range, incubation temperature and time, and agricultural wastes as potential low-cost substrates) on the thermophilic laccase production performance from Bacillus licheniformis SO7 strain (GenBank No: MG076977) were evaluated in detail. Accordingly, optimal conditions were determined using statistical methods such as one-factor-at-time (OFAT) and Plackett-Burman desings to achieve the highest laccase production yield. Under these conditions, the impact of aromatic substrates on laccase production was investigated at the gene and the protein levels using qPCR and SDS-PAGE, respectively. Maximum laccase activity was obtained after 36 h of incubation under the following conditions: pH 8.0, 55 °C, 50 g/L maltose, 1 g/L fish peptone, 2.5 mM syringic acid, and 1 mM ZnCl2. The highest gene expression and protein level were found in the syringic acid-containing medium, correlating with the activity results. Furthermore, even in bacterial culture media containing only carrot peels, similarly high laccase enzyme activity was detected as in other substrates. This clearly demonstrates that agricultural wastes offer an economical, environmentally sustainable, and efficient alternative for bacterial growth and target enzyme production.
PMID:42584713 | DOI:10.1007/s00284-026-05091-x