9.6 Production of Similar Metabolites by Endophytic
Fungi and Host Plants
The long co-evolution of endophytes with their host plants has resulted a genetic
recombination. It has opened the path for some endophytes to produce the same
bioactive compounds originally characteristic of the host plant (Tan and Zou 2001 ).
Taxol(45), Berberine(46), Sanguinarine(47)Camptothecin (CPT)(48)producing
endophytic fungi are examples for this phenomenon. Taxol (paclitaxel)(45), the
first billion dollar anticancer drug was discovered initially fromTaxus brevifolia
and later from 11 otherTaxusspecies in the world (Stierie et al. 1993 ). Therefore, as
an alternative source, taxol producing endophytic fungi have been investigated from
these yew plants, andTaxomyces andreanae, was the initially discovered taxol
producing endophytic fungus from host plantTaxus brevifolia(Strobel 2003 ).
Berberine(46), with diverse pharmacological properties is an isoquinoline
alkaloid isolated from several medicinal plants including Berberis aristata,
Hydrastis canadensis, Coptis chinensis, Coptis rhizome, Coptis japonica,
Phellondendron amurense, and Coscinium fenestratum(Timothy et al. 1997 ;
Tillhon et al. 2012 ). This natural product is currently undergoing 10 clinical trials
(Tillhon et al. 2012 ). Berberine has also been reported from the endophytic fungus,
Fusarium solani, from the roots ofCoscinium fenestratuma critically endangered
plant species (Diana and Agastian 2013 ). SinceC. fenestratumalso been reported to
produce berberine, it supports the theory that, with the long co-evolution with the
host, an endophyte can adapt to the special microenvironments through genetic
modification which includes uptake of some plant DNA into their own genomes
(Germaine et al. 2004 ; Diana and Agastian 2013 ).
Sanguinarine(47)is an antimicrobial benzylisoquinoline alkaloid reported from
several plants belonging to the family Papaveraceae includingMacleaya cordata
(Nicoletti and Fiorentino 2015 ). This compound has also been isolated from the
endophytic fungal strain of Fusarium proliferatum inhabiting the leaves of
Macleaya cordata(Wang et al. 2014 ). CPT(48)is another anticancer agentfirst
isolated from the extracts ofCamptotheca acuminata, and later from several other
plants (Wall et al. 1966 ; Asano et al. 2004 ). The production of CPT inOphiorrhiza
mungoswasfirst reported by Tafur et al. ( 1976 ). Later, Salim et al. ( 2011 ) isolated
the CPT producing endophytic fungusGlomerella cingulatafrom O. mungos
providing an alternative strategy to reduce the need to harvest slow-growing and
possibly rare plants consequently helping to preserve the world’s ever diminishing
biodiversity. In addition, it is easier and more economical to produce a valued
phytochemical by exploiting a microbial source than using a plant, which even-
tually leads to increase availability and low market price (Radic and Strukelj 2012 ).
9 Endophytic Fungi: A Remarkable Source... 205