Azadirachtin biosynthesis induction in Azadirachta indica A. Juss cotyledonary calli with elicitor agents

Abstract

The use of cell and plant tissues culture techniques to produce economically important active metabolites has been growing. Among these substances, azadirachtin (AZA), produced by the neem tree (Azadirachta indica), has received considerable attention due to its bioinsecticide action. The main goal of this work was to analyze the AZA levels in neem cotyledonary calli. The calli were grown in agitated Woody Plant Medium (WPM) liquid medium, supplemented with glucose (Gl), hydrolyzed casein (HC) and methyl jasmonate (MeJ) as elicitor agent. An interaction was observed between these substances, depending on in vitro cultivation time with orbital agitation. The highest concentrations (average of 0.2470 µg g-1) of AZA were produced in the first and second weeks of culture when the cell mass was grown in a medium with 2% Gl v/v, 500 mg L-1 HC and 100 µM of MeJ. This corresponded to approximately 57% of the AZA content stored in the donor plants seeds, used as a source of explants to induce in vitro callus formation. It was concluded that the nutrition, as well as the concentration of MeJ as signal transduction of secondary metabolism in neem cells, might influence the AZA content produced in vitro.