We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Production and characterization of extracellular laccase from Bacillus aerius SP3 and its application in dye decolorization.
- Authors
Saranya, Palanisamy; Jayanthi, Singaram; Nagappan, Senthil
- Abstract
Laccases are lignolytic enzymes that catalyze and cleave various environmental pollutants. In this study, we isolated a novel laccase-producing bacterium, Bacillus aerius SP3, from compost soil using ABTS as the substrate. The production of extracellular laccase was improved through the one-factor-at-a-time (OFAT) method and response surface methodology using the Box–Behnken design (BBD) in submerged fermentation. Optimization of medium components, including 20 g/L starch, 10 g/L peptone, 3.36 mM CuSO4, and 72-h incubation time, resulted in a 3.46-fold increase in extracellular laccase production compared with the unoptimized medium. The extracellular laccase obtained from the culture supernatant was purified through 60% ammonium sulfate precipitation, dialysis, and ion exchange chromatography using a DEAE cellulose column. SDS-PAGE estimated the molecular weight of the isolated laccase to be approximately 60 kDa. The purified laccase also decolorized textile dyes, crystal violet and methylene blue, achieving 48% and 22% removal in the presence of ABTS as a mediator. The optimal temperature and pH for laccase activity were 35 °C and 7.0, respectively. The enzyme demonstrated stability up to 40 °C for 60 min and at pH 8.0 at 4 °C for 24 h. Cu2+ and Zn2+ enhanced laccase activity by 110%, while > 50% of activity was retained in the presence of heavy metals such as Hg2+ and Cd2+. Organic solvents, including 10% ethanol and methanol, increased laccase activity by 1.5 times. These results indicate that the laccase is active at neutral/alkaline pH, tolerant to heavy metals, and organic solvents. Enhancement of laccase activity by organic solvents is advantageous for chemical reactions in solvent environments and treating wastewater from dyeing industries.
- Subjects
GENTIAN violet; LACCASE; DYES &; dyeing; POLLUTANTS; ENZYME stability; BACILLUS (Bacteria); ION exchange chromatography; ORGANIC solvents
- Publication
Biologia, 2024, Vol 79, Issue 5, p1497
- ISSN
0006-3088
- Publication type
Article
- DOI
10.1007/s11756-024-01619-3