Decolourization of malachite green dye by endolichenic fungi from the lichen Usnea sp.: A novel study on their dye removal potential

Abstract

ObjectiveThis novel study explored the potential of two endolichenic fungi, Pseudopestalotiopsis theae (PT, accession number MG881833) and Astrocystis bambusae (AB, accession number MH370741) in decolorizing Malachite Green (MG). MethodsTheir efficacy in dye decolorization was compared to non-endolichenic fungus Trichoderma asperellum (TA, accession number KP792512). Decolorization test was performed using MG (100 ppm) for 14 days (absorbance at 617 nm) to determine decolorization efficiency (DE, %). The pellet was collected for FTIR analysis (4000 to 700 cm−1, 50-scan speed) while the supernatant was analysed with UV-spectral analysis (300–800 nm) to detect for biodegradation. ResultsP. theae demonstrated the highest decolorization efficiency (DE%) at 89.22%, followed by T. asperellum (76.19%) and A. bambusae (67.69%). Common functional groups (i.e., OH, COOH, NH, CH, CO, CH) were detected in all isolates and their roles in biosorption were evident by the shifts in peaks and peak intensity. Biodegradation of MG was concluded based on UV-spectra peaks at 617 nm, which were significantly reduced (or absent). ConclusionThis study is the first to reveal that endolichenic fungi P. theae and A. bambusae are capable of decolorizing the toxic dye malachite green.