Biodecolorization of Anthraquinone and Azo Dyes by Newly Isolated Indonesian White-Rot Fungi

Abstract

Water pollution by dyes represents from dyestuff industry becomes an environmental concern. Finding new isolates capable of decolorizing these dyes is important. The study aimed to assess the new isolates of white-rot fungi (WRF) as decolorizing agent of anthraquinone and azo dyes. Decolorization assay were conducted in Agar plates and liquid medium. During the decolorization, laccase activities produced by the fungal strains were analyzed. Identification of the fungal strains were investigated using molecular DNA analysis. The results showed that isolates M3, H18, and GP1 were able to decolorize anthraquinone and azo dyes in Agar and liquid medium. Based on DNA analysis, isolates M3, H18, and GP1 have the similarity to Trametes sanguinea, Trametes polyzona, and Neofomitella guangxiensis, respectively. Among the fungi, T. polyzona H18 exhibited high decolorization ability (70–90%) to the dyes (100 mg/L) after 96-hours incubation. Laccase activity was fluctuated during the reactions with tendency to increase at the beginning until its peak, then decreased at the end of incubation. This study demonstrated the potential of the new isolates from Indonesia to decolorize anthraquinone and azo dyes. The results of the study can provide an alteranative for bioremediation agents of contaminated water by synthetic dyes.

Bioprospecting three newly isolated white-rot fungi from Berbak-Sembilang National Park, Indonesia for biodecolorization of anthraquinone and azo dyes

“…According to Yesilada et al (2018), this phenomenon is possible due to the different physiological characteristics of each WRF fungal strain. Ramadhan et al (2021) found similar findings, which studied decolorization by using Trametes sanguinea, Trametes polyzona and Neofomitella guangxiensis. The results showed that T. polyzona had the highest performance of 95% RB5 and 77% Acid Orange 7 removal while N. guangxiensis could only remove 20-22% of these dyes within 96 hours.…”

“…The maximum decolorization percentages showed a competitive performance compared to other studies. In the recent work by Ramadhan et al (2021), three newly isolated WRF (Trametes sanguinea, Neofomitella guangxiensis and Trametes polyzona) could remove 59-89% of AB129 in 96 h which was slightly lower than the maximum removal by BRB81 (91%). The BRB 81 also showed a higher decolorization of RBBR dye (51%) compared to other Ceriporia sp.…”

“…The isolate BRB 11 had the most active isolate to grow and decolorize RBBR dyes in the medium compared to other strains (Table 2). Previous studies showed the growth rate of fungal strain has a positive correlation to the decolorization activity (Kaur et al 2015;Hefnawy et al 2017;Ramadhan et al 2021). However, in the case of fungal strain BRB 73 and BRB 81, the decolorization rate did not along with the growth rate.…”

“…In the next screening, the positive isolates were grown in the agar medium containing lignin and RBBR synthetic dyes (100 ppm). Ramadhan et al (2021) reported, the preliminary screening using two-layer agar media containing anthraquinone dye such as RBBR or AB129 on the top layer and lignin in the bottom layer effectively selected the promising white-rot fungi isolates for dye removal application. Among 13 isolates, only three promising isolates grew well and decolorized RBBR (Table 1), producing a clear zone around the mycelia (Figure 3).…”

A new technique to estimate percentage decolorization of synthetic dyes on solid media by extracellular laccase from white-rot fungus

“…In another experiment, the synthetic dye decolorization capacity of tested fungal strains was evaluated by a semiquantitative agar-plate test that considered the diameter of mycelia and diameter of decolorized zone on a five-point scale (Eichlerov a & Baldarian 2020) to evaluate the extent of decolorization without involving any calculation to determine %decolorization. In a study by Ramadhan et al 2021, the mycelial diameter and diameter of decolorization zone were measured separately and the extent of decolorization was directly correlated to the mycelial diameter but no calculation was done to prove it quantitatively. In this regard, a research group (Si, Cui, and Dai 2013) in their work had devised a quantitative method to calculate the percentage of dye decolorization on solid medium plate as decolorization rate (%) that involves the ratio of diameter of decolorizing circle (or decolorized zone) to the plate diameter (90 mm).…”