Endophytes Crop Productivity and Protection Volume 2 (Sustainable Development and Biodiversity)

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Chapter 3

Endophytic Fungi Bioremediation

Yelugere L. Krishnamurthy and B. Shankar Naik


Abstract Fungal endophytes are isolated from almost every host plant studied so


far. The relationship between endophytes and host plants involves both mutualism


and antagonism. Plants have many mechanisms to limit the growth of endophytes


which include producing a variety of toxic metabolites such as terpenoides. But


over a long period of co-evolution, endophytes have gradually formed a variety of


tolerant mechanisms towards host metabolites by producing exo enzymes and


mycotoxins. These enzymes include pectinase, cellulase, lipoidase, proteinase,


phenol oxidase and lignin catabolic enzymes. When host plants die the fungi utilize


the carbon source, plant residues such as glucose, oligosaccharides, cellulose,


hemicelluloses, lignin, keratin, pectin, lipids and proteins and decomposes effec-


tively. These enzymes may also degrade macromolecule compounds into small


molecules or convert more toxic substances into less toxic in order to increase their


adaptability. The use of fungi to clean up environmental pollutants has gained


momentum in the past few years. However, most studies have focussed on white rot
fungi and use of endophytic fungi might be a novel and important source for


degradation of toxic pollutants including hydrocarbons, polychlorinated biphenyl’s


(PCBs), polyaromatic hydrocarbons (PAHs), radionuclides, and metals.


Phytoremediation is another important bioremediation aspects of endophytic fungi


in soils contaminated with hydrocarbons and heavy metals. Depolymerisations is


one of the most efficient methods of plastic waste management by endophytic


fungal enzymatic action. Complex polymers disintegrate into short chains of oli-


gomers, dimers and monomers which can act as a source of carbon and energy. The


enzymes produced by the microbes vary with the species even between strains of


the same species. Enzymes are very specific in their action on substrates so that


different enzymes help in the degradation of various types of enzymes.


Y.L. Krishnamurthy (&)
Department of P.G. Studies and Research in Applied Botany, Bioscience Complex,
Kuvempu University, Jnanasahyadri, 577 451 Shimoga, Karnataka, India
e-mail: [email protected]


B.S. Naik
Department of Biology, Govt. Science College, 577 101 Chikmagalur, Karnataka, India
e-mail: [email protected]


©Springer International Publishing AG 2017
D.K. Maheshwari and K. Annapurna (eds.),Endophytes: Crop Productivity
and Protection, Sustainable Development and Biodiversity 16,
DOI 10.1007/978-3-319-66544-3_3


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