Rapid discrimination of secondary metabolite production caused by endophytic bacteria on Alkanna tinctoria (L.) Tausch calli based on untargeted HPTLC metabolomics

Rhizospehric microorganisms tightly interact with their host plant by influencing her growth and modulating her metabolome. As proof of a concept, the effect of the extracellular medium and bacteria cells homogenate of five strain suspensions belonging to Chitinophaga sp., Xanthomonas sp., Pseudomonas sp., Allorhizobium sp., Micromonospora sp. were tested on in vitro callus culture of Alkanna tinctoria (L.) Tausch. For rapid discrimination of callus metabolome modification, a High-Performance Thin-Layer Chromatography (HPTLC) image-fingerprints analysis method was developed. As a result of the multivariate analysis, bacteria cells homogenate and extracellular medium induced the production of different kinds of secondary metabolites. Chitinophaga sp. and Allorhizobium sp. bacteria extracellular medium were revealed as promising

“metabolome modulator” since the chemical fingerprint is close to the one elicited by phytohormonal elicitor: Methyl jasmonate. Crucial markers were then identified using a TLC-MS interface combined with UHPLC-MS analysis. In parallel, HTPLC-DPPH effect-directed analysis was performed and demonstrated the production of new antioxidant metabolites after 30 days of coculture. The developed HPTLC-based untargeted metabolomic method has proved to be a robust approach to monitor interactions among bacteria endophytes and their host plant. The results confirmed that endophytes play an essential role in the biotransformation/induction of compounds of interest.

This work has been financed by the EU H2020-ITN-MICROMETABOLITE project (Grant N°721635)

Publikationsverlauf

Artikel online veröffentlicht:
13. Dezember 2021