ARCHIVES
VOL. 10, ISSUE 11 (2025)
Optimization and characterization of a novel laccase from Geotrichum candidum Link for sustainable dye decolorization
Authors
Suju Skaria C
Abstract
The increasing environmental burden of synthetic dyes and lignin-rich
waste has intensified the demand for sustainable biocatalysts, particularly
microbial laccases, for bioremediation and industrial applications. While
white-rot basidiomycetes dominate laccase research, their slow growth,
pathogenic potential, and low yields under industrial conditions necessitate
exploration of alternative fungal sources. This study addresses this gap by
isolating a novel Geotrichum candidum Link strain (GenBank: KJ814246)
from tropical laterite soils—a promising yet underexplored reservoir of
ligninolytic microbes. The fungus was selected for its GRAS (Generally
Recognized as Safe) status and robust laccase production (253.45 U/L),
optimized through Response Surface Methodology, representing a 1.57-fold
enhancement over basal conditions. The 62 kDa monomeric laccase exhibited
unique dual pH optima (pH 5 for ABTS, pH 6 for syringaldazine) and retained
>80% activity at 40°C, demonstrating operational versatility. With a K<sub>m</sub>
of 0.637 mM for ABTS, the enzyme outperformed several fungal laccases in dye
decolorization, achieving 92% methyl red and 81% Congo red degradation within 3
hours without mediators—a critical advantage for industrial wastewater treatment.
Statistical optimization identified malt extract (4.39 g/L) and pH 6.21 as key
production parameters, while inhibition studies confirmed classical
copper-dependent catalysis (54% inhibition by NaN₃). This work establishes G.
candidum Link as a sustainable alternative to traditional laccase
producers, addressing two key industry demands: (1) non-pathogenic, high-yield
enzyme sources compatible with mild processing conditions, and (2) efficient,
mediator-free dye degradation systems aligned with EU’s 2024 wastewater
mandates. The findings highlight the untapped potential of soil-derived
deuteromycetes in circular bioeconomy strategies.
Download
Pages:48-58
How to cite this article:
Suju Skaria C "Optimization and characterization of a novel laccase from <i>Geotrichum candidum</i> Link for sustainable dye decolorization". International Journal of Botany Studies, Vol 10, Issue 11, 2025, Pages 48-58
Download Author Certificate
Please enter the email address corresponding to this article submission to download your certificate.