An endophytic fungus from Azadirachta indica A. Juss. that produces azadirachtin

Azadirachtin A and its structural analogues are a well-known class of natural insecticides having antifeedant and insect growth-regulating properties. These compounds are exclusive to the neem tree, Azadirachta indica A. Juss, from where they are currently sourced. Here we report for the first time, the isolation and characterization of a novel endophytic fungus from A. indica, which produces azadirachtin A and B in rich mycological medium (Sabouraud dextrose broth), under shake-flask fermentation conditions. The fungus was identified as Eupenicillium parvum by ITS analysis (ITS1 and ITS2 regions and the intervening 5.8S rDNA region). Azadirachtin A and B were identified and quantified by LC-HRMS and LC-HRMS2, and by comparison with the authentic reference standards. The biosynthesis of azadirachtin A and B by the cultured endophyte, which is also produced by the host neem plant, provides an exciting platform for further scientific exploration within both the ecological and biochemical contexts.