Lenzites elegans KSG32: A Novel White Rot Fungus for Synthetic Dye Decolourization

Abstract

Lenzites elegans, a ligninolytic enzyme producing white rot fungus with proficient synthetic dye decolourization ability was isolated from decaying wood. To the extent of our knowledge, this is the first report of laccase (362.7 IU/mL) and lignin peroxidase (5.17 IU/mL) production by L. elegans KSG32. The synthetic dye decolorizing ability of the fungus was checked using solid and liquid media. The organism showed greater ability for decolourization of naphthol green B (97%) and bromophenol blue (88%) in the submerged condition followed by partial decolourization for two azo dyes, namely, orange G (70%) and congo red (62%). This is an indicative of the potential application of L. elegans KSG32 in decolourization of colored industrial effluent. The FTIR analysis of the decolourized dye sample showed that major bonds in the dye were broken and oxidation process also increased. The analysis of biomass content showed no growth inhibition of L. elegans KSG32 in the presence of dyes, indicating the less toxicity of these dyes on fungal growth. for 15 min. The moisture content was adjusted to 90% using 0.1 M citrate buffer (pH 5). Three mycelial plugs of size 1 cm2 from 6 days old PDA plate culture were used as inoculum. Inoculated flasks were incubated at room temperature for 5 days. Keywords: Extraction of crude enzymeAfter incubation, the crude enzyme was extracted by adding 50mL 0.1 M citrate buffer (pH 5) to each flask. The culture supernatant was collected after centrifugation at 10,000 rpm for 10 min at 4 C and stored at 4 C.

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

“…In general, the azo dyes owing to their chemical structures are subtly decolorized and degraded but on the other hand, become easily and surprisingly decolorized by white rot fungi (Koyani et al 2013). The strain experimented in this investigation responded positively with regard to decolorization of Congo red (azo dye) which agrees with the earlier studies performed extensively on synthetic dye decolorization using white rot fungi (Lakshmi, Soumya, and Shaji 2017).…”