Endophytic fungi which live inside plant tissues as asymptomatic mutualists have been recognized as an important and novel source of bioactive compounds. They produce a number of important secondary metabolites, including anti-cancer, anti-fungal, anti-diabetic and immunosuppressant compounds Some
of these compounds are those produced by their respective host plants as well. For example, Stierle et al. showed that an endophytic fungus, Taxomyces andre- anae isolated from the yew plant, Taxus brevifolia produced paclitaxol, the multi-billion dollar anti-cancer compound, just as it is produced by the yew plant. Following this report, a number of endophytic fungal sources of important plant secondary metabolites including camptothecin (CPT), podophyllotoxin, vinblastine, hypericin, diosgenin, azadirachtin and rohitukine have been reported (Table 1). These findings have triggered the expectation that endophytic fungi can be a source of important plant metabolites,thus relieving our dependence on plants for these metabolites.