Abstract

It has been shown that the mould fungus Aspergillus carbonarius, which synthesizes extracellular melanin, is able to develop due to the degradation of cellulose inside the cardboard under conditions of low water availability. The maximum yield of melanin was noted in a slightly alkaline medium, but in the presence of copper ions, a high level of pigmentation of the medium is also observed at low pH values. Melanized mycelium and exomelanin are characterized by a high sorption capacity in relation to heavy metal ions present in printing pigments of waste paper. In the process of growth A. carbonarius decreases acidity from neutral values to pH 2.8–3.1, increases the mobility of heavy metals immobilized on cellulose fibers and binds them by functional groups via ionic or chelating pathways. The sorption capacity of biomass with respect to copper, zinc, and nickel ions increased in the order of viable mycelium < inactivated mycelium < exomelanin. Lead ions were most actively bound by inactivated mycelium. The extracellular pigment accumulated copper better than other metals. The distribution coefficient in the system melanin – Cu2+ reached 1390 ml/g.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call