Mycoremediation of Paper, Pulp and Cardboard Industrial Wastes and Pollutants

Evaluation of the Carbon Dioxide Production by Fungi Under Different Growing Conditions

Production of carbon dioxide, as one of the ultimate products of fungal metabolism, can be used to quantify and measure their metabolic rate under different conditions, thus aiding in finding the optimal substrate and environment for cultivation of wood-destroying fungi. This study is focused on species Pleurotus ostreatus and Ganoderma lucidum,. These species are also cultivated for mycorestoration as well as their medicinal and nutritional value. To quantify their metabolical rate on various substrates (agar medium, wood chips, rye straw), multiple custom-built airtight chambers were equipped with CO₂ probes (GMP 343, Vaisala, Finland) to measure the production of carbon dioxide. The highest values were measured during the primordial production on rye straw substrate, with the average values of 1.09 g CO₂ kg^-1 (substrate) h^-1. These values varied significantly between various substrates, fungal species and development stages.

Fungal bio-sorption potential of chromium in Norkrans liquid medium by shake flask technique

In this study, the myco-reduction potential of fungi isolated from soil was ascertained by Norkrans shake flask experiment contaminated with chromium(VI). Fungal tolerance assay and induced tolerance training of the fungi were also carried out. Aspergillus niger, Penicillium, and Saccharomyces strains were isolated from the soil samples using culture based technique. Norkrans samples were collected and analyzed for Cr(VI) concentration using diphenylcarbazide spectrophotometric method. Penicillium strain was observed to be most effect at Cr(VI) concentrations of 16.1 and 8.1 mg L^-1 since it was able to reduce Cr(VI) more than Saccharomyces strain and A. niger on day 20. Bio-sorption kinetics for this study was better described by pseudo second order model while Langmuir isotherm model fitted better to the equilibrium data. There was virtually steady increase in fungal growth for all the treatments through-out the experimental period. Significant negative correlation (p < 0.05) was observed between fungal growth and Cr(VI) reduction rate. The results from the induced tolerance training showed that Penicillium had the highest tolerance index (TI) values at 18, 20, and 25 mg L^-1 concentrations of Cr(VI) compared to A. niger and Saccharomyces strain. These results demonstrated that these fungi have the potential to bio-absorb Cr(VI) and if properly harnessed, could be used in place of conventional remediation technology to clean-up the Cr(VI) contaminant in the field.

Sandal reactive dyes decolorization and cytotoxicity reduction using manganese peroxidase immobilized onto polyvinyl alcohol-alginate beads

Background

Fungal manganese peroxidases (MnPs) have great potential as bio-remediating agents and can be used continuously in the immobilized form like many other enzymes.

Results

In the present study, purified manganese peroxidase (MnP) enzyme isolated from Ganoderma lucidum IBL-05 was immobilized onto polyvinyl alcohol-alginate beads and investigated its potential for the decolorization and detoxification of new class of reactive dyes and textile wastewater. The optimal conditions for MnP immobilization were 10 % (w/v) PVA, 1.5 % sodium alginate, 3 % boric acid and 2 % CaCl₂ solution. The optimum pH, temperature and kinetic parameters (K_m and V_max) for free and immobilized MnP were found to be significantly altered after immobilization. The immobilized MnP showed high decolorization efficiency for Sandal reactive dyes (78.14–92.29 %) and textile wastewater (61–80 %). Reusability studies showed that after six consecutive dye decolorization cycles, the PVA coupled MnP retained more than 60 % of its initial activity (64.9 % after 6th cycle form 92.29 % in 1st cycle) for Sandal-fix Foron Blue E₂BLN dye. The water quality assurance parameters (BOD, COD and TOC) and cytotoxicity (haemolytic and brine shrimp lethality tests) studies before and after treatment were employed and results revealed that both the dyes aqueous solution and textile wastewater were cytotoxic that reduced significantly after treatment.

Conclusions

The decolorization and cytotoxicity outcomes indicated that immobilized MnP in PVA–alginate beads can be efficiently exploited for industrial and environmental applications, especially for remediation of textile dyes containing wastewater effluents. Graphical abstract

Mushroom as a product and their role in mycoremediation

Mushroom has been used for consumption as product for a long time due to their flavor and richness in protein. Mushrooms are also known as mycoremediation tool because of their use in remediation of different types of pollutants. Mycoremediation relies on the efficient enzymes, produced by mushroom, for the degradation of various types of substrate and pollutants. Besides waste degradation, mushroom produced a vendible product for consumption. However, sometimes they absorb the pollutant in their mycelium (biosorption process) and cannot be consumed due to absorbed toxicants. This article reviews the achievement and current status of mycoremediation technology based on mushroom cultivation for the remediation of waste and also emphasizes on the importance of mushroom as product. This critical review is also focused on the safety aspects of mushroom cultivation on waste.