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

(Tina Meador) #1

5.3 Extracellular Enzymes from Endophytic Fungi


Endophytic fungi isolated from various plants sources have been reported for the


production of various kinds of extracellular enzymes from last two decades or so


(Khan et al. 2016 ; Esteves et al. 2014 ; Petrini et al. 1993 ). The categories of


enzymes have been described in Table5.1. Most of the endophytic fungi producing


extracellular enzymes have been reported from medicinal plants (Chathurdevi et al.
2016 ). The endophytic fungi have been reported to be xylanase producers including


Alternaria alternate(Wipusaree et al. 2011 ),Hymenoscyphus ericae(Burke and


Cairney 1997 ), and Aspergillus terreus (Sorgatto et al. 2012 ). Similarly,


Harnpicharnchai et al. ( 2009 ) showed that endophyte Periconia sp. produces


b-glucosidase. De-Almeida et al. ( 2012 ) reported that endophytes ofAcremonium


species produce cellulases and hemicellulases. In another study, Suto et al. ( 2002 )


isolated and identified one hundred andfifty-five fungal strains showing their ability


to produce xylanases. Silva et al. ( 2006 ) investigated the fungal strain isolated from


Annonaspp., while Luz et al. ( 2006 ) fromPassiflora edulisto understand their


potential for extracellular enzymes production.


Gazis and Chaverri ( 2010 ) isolated and identified various endophytic strains


belonging toXylariaceaeandAnnulohypoxylonsp. from a medicinal plantHevea


brasiliensis. Earlier, Wei et al. ( 1992 ) grownA. stigyumstrain and found that this


strain producesb-glucosidase with a very low level of cellulases. Some of the


common endophytes such asAlternariaspecies have been isolated from eucalyptus


plants such asEucalyptus globulus(Lupo et al. 2001 ) andEucalyptus citriodora


(Kharwar et al. 2010 ). Strains of A. alternataare able to produce endopoly


galactunorase (Isshiki et al. 1997 ) in the presence of pectin, andb-glucosidase in


the presence of saccharose (Sáenz-de-Santamaria et al. 2016 ).


Among other common endophytic strains,A. nigerwas also found to produce


extracellular enzymes, which is famous to produce an extensive range of extra-


cellular glucohydrolases (b-glucosidase, pectinases, and xylanases; Ward et al.
2005 ). Such attributes are always helpful to fungus to colonize and propagate across


different kinds of environments and plant hosts (Meijer et al. 2011 ). Chow and Ting


( 2015 ) reported that endophytic fungi belonging toColletrotrichum, Fusarium,


Phoma,andPenicilliumspecies are producing l-Asparaginase in their pure culture


isolated from anticancer medicinal plants.


A semiarid plantOpuntiaficus-indicawas subjected to endophyte isolation,


which resulted in the identification of 44 endophytic fungi (Bezerra et al. 2012 ).


According to the screening assays for extracellular enzymes,Aspergillus japonicus


andPenicillium glandicolahave shown significant pectinolytic activity. In addition,


the author showed that endophytes belonging toXylariasp. were showing signif-


icantly higher xylanase and cellulase activity. In a recent study by Khan et al.


( 2016 ), 18 different endophytic fungi isolated from the bark and leaf parts of the


98 A.L. Khan et al.


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