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

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On the other hand, amylases (aamylase,b-amylases and glucoamylases) which


are the amylolytic enzymes convert starch into different sugar solutions also con-


tained in endophytic fungi. Fungal amylases especially glucoamylases are widely


used in industries.Aspergillussp. andRhizopussp. are often used as sources for the


production of glucoamylases (Pandey et al. 2000 ). In a study endophytic


Fusicoccum sp. showed strong amylolytic activity under in vitro conditions


(Champreda et al. 2007 ). Similarly, the endophyticCylindro cephalumsp. isolated


from medicinal plantAlpinia calcarata(Haw.) Roscoe found to produce amylase


under 30 °C and at pH 7.0 in the presence of maltose and sodium nitrate sources


(Sunitha et al. 2012 ). In another study, enzymes of endophytic strains belonged to


Gibberella pulicaris, Acremoniumsp., and Nodulisporiumsp. hydrolysed raw


sagostarch to produce solely glucose whereas amylases ofSynnematoussp. pro-


duced glucose and maltose (Marlida et al. 2000 ).


Another import enzyme secreted by a group of endophytic fungi are lipases


which are hydrolytic enzymes that in vivo break the ester bond of triacyl glycerol


releasing free fatty acids and glycerol being then classified as a special class of


esterases (Oliveira et al. 2012 ). They also catalyze interesterification, alcoholysis,


acidolysis, esterification and aminolysis reactions under proper conditions


(Damassoet al. 2008 ). EndophyticRhizopusoryzaeisolated from Mediterranean


plants found to be producers of membrane bound lipases (Torres et al. 2003 ).
Similarly, protees are enzymes which hydrolyse peptide bonds of proteins, they are


also called proteolytic enzymes or proteinases. Few year back, a novelfibrinolytic


enzyme was discovered from endophytic Fusarium sp. isolated from


Chrysanthemumstems (Wu et al. 2009 ).


Fungi are the major decomposers of lignocelluloses in several ecosystems and


play an essential role in cycling of carbon and other nutrients. The main hydrolytic


enzymes involved in lignocelluloses degradation are exo and endoglucanases,


b-glycosidase, exo and endoxylanases and b-xylosidases (Dyk and Pletschke


2012 ). Correa et al. ( 2014 ) reported that for complete degradation of lignocellulose


materials, laccases, manganese peroxidise and lignin peroxidise (oxidative


enzymes) and additional hemicelluloses (e.g., acetyl esterase, b-glucuronidase,


endo-1, 4-b-mannanase,a-galactosidase) and oxidoreductases (aryl alcohol oxi-


dase, glucose-1-oxidase, glyoxal oxidase, pyranose-2-oxidase) are also needed.


3.3 Endophytic Fungi and Nutrient Cycling


The importance of phyllospheric endophytic fungi to ecosystem functioning via soil


processes has aroused increasing interest during the past decade. The endophytes


may affect plant litter quality, organisms that control litter decomposition, and the


availability of nutrients in plant communities. Endophytes are likely to affect the


decomposition of plant litter and soil nutrient trans formations at least in three ways


(i) by acting as saprophytes in abscised plant parts and aiding their decay (ii) by
affecting the amount and/or quality of plant litter (iii) by affecting the abundance


3 Endophytic Fungi Bioremediation 51


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