
Tree bark scrape fungus: A potential source of laccase for application in bioremediation of non-textile dyes
Author(s) -
R. Z. Sayyed,
H. M. Bhamare,
. Sapna,
Najat Marraiki,
Abdallah M. Elgorban,
Asad Syed,
Hesham Ali ElEnshasy,
Daniel Joe Dailin
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0229968
Subject(s) - laccase , bioremediation , enzyme , chemistry , aspergillus oryzae , sephadex , substrate (aquarium) , biochemistry , solid state fermentation , aspergillus flavus , enzyme assay , chromatography , food science , biology , bacteria , ecology , genetics
Although laccase has been recognized as a wonder molecule and green enzyme, the use of low yielding fungal strains, poor production, purification, and low enzyme kinetics have hampered its large-scale application. Thus,this study aims to select high yielding fungal strains and optimize the production, purification, and kinetics of laccase of Aspergillus sp. HB_RZ4. The results obtained indicated that Aspergillus sp. HB_RZ4 produced a significantly large amount of laccase under meso-acidophilic shaking conditions in a medium containing glucose and yeast extract. A 25 μM CuSO 4 was observed to enhance the enzyme yield. The enzyme was best purified on a Sephadex G-100 column. The purified enzyme resembled laccase of A . flavus . The kinetics of the purified enzyme revealed high substrate specificity and good velocity of reaction,using ABTS as a substrate. The enzyme was observed to be stable over various pH values and temperatures. The peptide structure of the purified enzyme was found to resemble laccase of A . kawachii IFO 4308. The fungus was observed to decolorize various dyes independent of the requirement of a laccase mediator system. Aspergillus sp. HB_RZ4 was observed to be a potent natural producer of laccase, and it decolorized the dyes even in the absence of a laccase mediator system. Thus, it can be used for bioremediation of effluent that contains non-textile dyes.