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	[[Image:cunninghamella elegans.jpg|thumb|Cunninghamella elegans <http://www.aikis.or.jp>|left|240px]]		[[Image:cunninghamella elegans.jpg|thumb|Cunninghamella elegans <http://www.aikis.or.jp>|left|240px]]
-	The fungi species [http://en.wikipedia.org/wiki/Cunninghamella_elegans Cunninghamella elegans] is becoming an organism of interest due to its ability breakdown polycyclic aromatic hydrocarbons. These compounds originate from from the combustion of fossil fuels.	+	The fungi species [http://en.wikipedia.org/wiki/Cunninghamella_elegans Cunninghamella elegans] is becoming an organism of interest due to its ability breakdown polycyclic aromatic hydrocarbons. These compounds originate from the combustion of fossil fuels.
	[[Phanerochaete chrysosporium]]		[[Phanerochaete chrysosporium]]

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Revision as of 13:47, 21 March 2013

Contents 1 Use of Fungi in Remediation 1.1 Introduction 2 History 3 Processes Involved 3.1 In situ 3.2 Ex situ 3.3 Metabolic Processes 4 Species Types Involved 4.1 Glomus mosseae 4.2 Phanerochaete chrysosporium 4.3 Cunninghamella elegans 5 Definitions 6 References

Use of Fungi in Remediation

Introduction

History

Processes Involved

In situ

The in situ bioremediation method keeps the contaminated material in its place that it exists and performs the treatment. Some examples of in situ bioremediation include bioventing, bioaugmentation, biosparging, biostimulation, and biodegradation. ^{[1] [2]}

Ex situ

The ex situ bioremediation method involves the removal of the contaminated material to perform treatment processes. Some examples of ex situ bioremediation include land farming, composting, bioreactors, and biopiles. ^{[3] [4]}

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Metabolic Processes

Bioremediation includes the degradation of organic substrates, including wood. Plant biomass is a complex network of polysaccharides, proteins, and lignin which can be digested and metabolized by a variety of species of Ascomycota and Basidiomycota fungi ^[6]. The degradation of lignin by these fungi is considered to be the rate-limiting step in releasing carbon from environments high in lignocellulose compounds. Lignin is a substrate for secondary metabolism, which has to be degraded in order for the fungi to be able to access cellulose as an energy source for primary metabolism. There are three enzymes required to break down are peroxidises, phenoloxidase, and laccase. There are also other enzymes that aid in the digestion of lignin by providing substrates required by the three enzymes named above ^[7]. These enzymes are involved in demethoxylation, ring hydroxylation and side chain oxidation rather than cleaving the compound as a whole ^[8].

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lignin

Species Types Involved

• It has been observed that a wide variety of fungal species have proved effective in remediation treatment; more notably are those of Basidiomycota and Ascomycota. Although these phylum's dominate the majority of the fungi used in remediation, there is evidence that Zygomycota and Glycomycota may also be effective. Within the studies it is reiterated that the reason for the effectiveness of the fungi in remediation lies in the activity of the corresponding enzymes.

Glomus mosseae

Ecological problems have given rise to the exploitation of natural resources, causing pollution and degradation of the environment. In turn, this gives rise to unfavourable conditions for plant growth because of the depleted nutrient acquisition. AM, fungi help increase nutrient supply and build resistance to biotic and abiotic stresses. In areas of pollution, plants are extremely dependent on these fungi to enhance their metabolic activity and diminish the effects of environmental stress.

Belonging to the phylum Glomeromycota, Glomus mosseae is beneficial in encouraging the revegetation of copper (Cu) mine tailings. These tailings are known to damage native vegetation, and contaminate water, land, and air. Metal pollution cause extreme environmental problems for plant growth and development in infected areas. This species is most greatly used as it belongs to arbuscular mycorrhizal fungi, which helps promote plant growth and increase in biomass in metal contaminated soils/substrates. They supply plants with mineral nutrients (especially phosphate and trace elements), improve soil structure (external hyphae and glomalin excreted by external hyphae), and maintain ecosystem stability. Also, they protect host plants against high metal concentrations in soils under metal contamination. Therefore, AM fungi is specifically used to revegetate at mining sites.

The plant species P. vitta and C.Dummundiiinhabit the Cu mine tailings of Tongling southern China, and are extremely dependent on mycorrhizal colonization for growth. These mining sites show a low supply of essential mineral nutrients with excessive metals, and a lower supply of essential plant nutrients. Glomus mussaea help plants obtain more nutrients so resistance to metal contamination can be enhanced. Also, under high metal concentrations in the soil, AM fungi protects host plants against metal toxicity.

Phanerochaete chrysosporium

Species of Basidiomycota, Phanerochaete chrysosporium has proven effective in the decolourization of direct dye wastewater, thus making it a successful remediation tool. The reason for this study resided in the fact that many bodies of water are now affected by the amount of dyes used commercially. The ability of basidiomycota to depolarize and mineralize lignin resulted in the degrading synthetic dyes; treatment demonstrated a 90% decolourization within just 7 days of treatment.

Within P. Chrysosporium are multiple extracellular lignin-modifying enzymes that are responsible for degrading a wide variety of compounds. This is due to their low substance specificity; other fungi lack certain structures and show specification making them unable to decolourize certain dyes. Once again, extracellular lignin-modifying enzymes proved prolific when decolourizing direct dye wastewater. There are multiple enzymes involved in the extracellular lignin-modifying process; the most successful enzyme for decolourizing dyes was manganese peroxidises (MnP).

In addition to the efficient enzymes P. Chrysosporium is also superior at decolourizing dyes due to its high pH value and its complex structures. P. Chrysosporium has a pH value of 9 whereas most other fungi possess a pH value in the acidic range, therefore making it more useful in this process. Also the complex –Trisazo, Polyazo and Stilbene structures further assist in the decolourization for direct dye wastewater.

To summarize Phanerochaete chrysosporium is very effective in remediation and possesses great qualities that allow it to be successful in decolourizing direct dye wastewater. These qualities consist of a high pH value, extracellular lignin-modifying enzymes and complex structures; they work as one to denature and eliminate dyes from water bodies around the world. P. Chrysosporium will continue to be used a remediation tool due to its safe and efficient results.

Cunninghamella elegans

The fungi species Cunninghamella elegans is becoming an organism of interest due to its ability breakdown polycyclic aromatic hydrocarbons. These compounds originate from the combustion of fossil fuels.

Phanerochaete chrysosporium Pleurotus Ostreatus

Pleurotus pulmonarius Trichoderma harzianum

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info^[25]

Definitions

References

1. ↑ Boopathy, R. (2000). Factors limiting bioremediation technologies. Bioresource Technology, 74, 63-67
2. ↑ Vidali, M. (2001). Bioremediation. An overview. Pure and Applied Chemistry, 73 (7), 1163-1172
3. ↑ Boopathy, R. (2000). Factors limiting bioremediation technologies. Bioresource Technology, 74, 63-67
4. ↑ Vidali, M. (2001). Bioremediation. An overview. Pure and Applied Chemistry, 73 (7), 1163-1172
5. ↑ Vidali, M. (2001). Bioremediation. An overview. Pure and Applied Chemistry, 73 (7), 1163-1172
6. ↑ Moore, D., Robson, G.D., Trinci, A.P.J. (2011). 21st Century Guidebook to Fungi. Cambridge, UK: Cambridge University Press
7. ↑ Pointing, S.b. (2001). Feasibility of bioremediation by white-rot fungi. Applied Microbiology and Biotechnology, 57, 20-33
8. ↑ Meharg, A.A. & Cairney, J.W.G. (2000). Ectomycorrhizas - extending the capabilities of rhizosphere remediation? Soil Biology & Biochemistry, 32(11-12), 1475-1484.
9. ↑ Vidali, M. (2001). Bioremediation. An overview. Pure and Applied Chemistry, 73 (7), 1163-1172
10. ↑ Pointing, S.b. (2001). Feasibility of bioremediation by white-rot fungi. Applied Microbiology and Biotechnology, 57, 20-33
11. ↑ Moore, D., Robson, G.D., Trinci, A.P.J. (2011). 21st Century Guidebook to Fungi. Cambridge, UK: Cambridge University Press
12. ↑ Boopathy, R. (2000). Factors limiting bioremediation technologies. Bioresource Technology, 74, 63-67
13. ↑ Balba, M.T., Al-Awadhi, N., Al-Daher, R. (1998). Bioremediation of oil-contaminated soil: microbiological methods for feasibility assessment and field evaluation. Journal of Microbiological Methods, 32, 155-164.
14. ↑ Tortella, G.R. & Diez, M.C. (2005). Fungal diversity and use in decomposition of environmental pollutants. Critical Reviews in Microbiology, 31(4), 197-212.
15. ↑ Chen,B.D. Duan, J. Smith S.E. Xiao, X.Y. Zhu, Y.G (2007). Effects of the Arbuscular Mycorrhizal Fungus Glomus mosseae on Growth and Metal Uptake by Four Plant Species in Copper Mine Tailings. Environmental Pollution;(147) 374-380.
16. ↑ Geyer, R. Kastner, M. Richnow, H. Russow, R. Weib, M (2004). Fate and Metabolism of [N]2,4,6-Trinitrotoluene in Soil. Environmetal Toxicology and Chemistry 23(8) 1852-1860.
17. ↑ Gadd, G.M. (2007). Geomycology: biogeochemical transformations of rocks, minerals, metals and radionuclides by fungi, bioweathering and bioremediation. Mycological Research, 111(1), 3-49.
18. ↑ Santelli, C.M., Pfister, D.H., Lazarus, D., Sun, Lu, Burgos, W.D. & Hansel, C.M. (2010). Promotion of Mn(II) oxidation and remediation of coal mine grainage in passive treatment systems by diverse fungal and bacterial communities. Applied and Environmental Microbiology, 76(14), 4871–4875.
19. ↑ Azcon, R. Barea, J.M. Biro, B. Ruiz-Lozano, J.M. Vivas, A. Voros, A (2003). Beneficial Effects of Indigenous Cd-tolerant and Cd-sensitive GLomus mosseae Associated with a Cd-adapted Strain of Brevibacillus sp. in Improving Plant Tolerance to Cd Contamination. Applied Soil Mycology 24(3) 177-186.
20. ↑ Faraco, V., Pezzella, C., Miele, A., Giardina, P. & Sannia, G. (2009). Bio-remediation of colored industrial wastewaters by the white-rot fungi Phanerochaete chrysosporium and Pleurotus ostreatus and their enzymes. Biodegradation, 20(2), 209-220.
21. ↑ Adams, P., Lynch, J., & De Leij, F. (2007). Desorption of zinc by extracellularly produced metabolites of Trichoderma harzianum, Trichoderma reesei and Coriolus versicolor. Journal Of Applied Microbiology, 103(6), 2240-2247.
22. ↑ Carvalho, M. B., Martins, I., Leitão, M. C., Garcia, H., Rodrigues, C., San Romão, V., & Pereira, C. (2009). Screening pentachlorophenol degradation ability by environmental fungal strains belonging to the phyla Ascomycota and Zygomycota. Journal Of Industrial Microbiology & Biotechnology, 36(10), 1249-1256. doi:10.1007/s10295-009-0603-2.
23. ↑ Juárez, R., Dorry, L., Bello-Mendoza, R., & Sánchez, J. (2011). Use of spent substrate after Pleurotus pulmonarius cultivation for the treatment of chlorothalonil containing wastewater. Journal Of Environmental Management, 92(3), 948-952. doi:10.1016/j.jenvman.2010.10.047.
24. ↑ Meharg, A.A. & Cairney, J.W.G. (2000). Ectomycorrhizas - extending the capabilities of rhizosphere remediation? Soil Biology & Biochemistry, 32(11-12), 1475-1484.
25. ↑ ^{25.0 25.1} Strong, P.J. (2008). Fungal remediation and subsequent methanogenic digestion of sixteen winery wastewaters. South African Journal of Enology & Viticulture, 29(2), 85-93.