Optimization of nutritional conditions for the mycoremediation of the synthetic dyes

摘要

Ligninolytic fungi are able to degrade the synthetic dyes, a class of xenobiotics resistant to biological degradation. The category and concentration of nutrients present a particular importance in the development of mycoremediation strategies. In this study, two isolates of lignicolous macromycetes species, Bjerkandera adusta and Trametes hirsuta, were tested on solid nutritive media to remedy different structural classes of dyes: azo, thiazine and arylmethane. We have evaluated various carbon and nitrogen sources in terms of quality and quantity in order to optimize the culture conditions. The results varied with the species, the dye used and nutrients tested. Substrates providing a rapid development of fungi have reduced the rate of degradation, and an elevated concentration of them expressed a negative effect on the degradation. Sucrose, mannitol and sorbitol used as carbon sources and energy have stimulated the discoloration while starch showed satisfactory effects. Among nitrogen sources, organic ones stimulated the development of fungi and discoloration. The study proved that cheap and affordable nutritional substrates as various salts, polyalcohols, agricultural by-products, supplemented in moderate concentrations can be successfully used in the mycoremediation processes. We have established the optimum nutrient concentrations for the synthetic dyes mycoremediation processes.