Metabolômica por ressonância magnética nuclear de Annona spp para o controle de nematoides

Abstract

Plant-parasitic nematodes are parasitizes highly specialized that infest plants, specially roots, causing economic losses to plant production of different cultures. The resistance of some species of the Annona genus to nematodes has been observed and reported. However, the mechanism has not been identified yet, neither the metabolites responsible for the resistance. This work presents a 1H NMR-based metabolomic studies applied to Annona genus with the aim to evaluate and correlate the metabolic profile of these plants to their nematicidal or nematode repellent activity. Initially the resistance of Annona muricata to the nematode Meloidogyne javanica through the comparison of the metaboloma of roots and leaves of infected and not infected plants wasevaluated. The plant infested with the nematodes showed metabolic alteration after 24 hours of infestation. The results suggest that the resistance of A. muricata to to the nematode Meloidogynejavanica can be related to a hypersensitivity reaction. Several metabolites related to nematode resistance could be identified in the roots and leaves of A. muricata by using the 1H NMR such as dopamine, xanthine and acetogenins. This work also evaluated the potencial of 1H NMR andpartial least-squares analyses to predicting the larvicidal activity of leaf Annona muricata extracts. For this, it was constructed a calibration model using as imput the 1H NMR signals between 0.00 to 10.00 and the DL50 values of the leaf extracts obtained in the Artemia salinalarvicidal test. The results showed the potential of 1H NMR in the development of methodologies to predicting the biological activities. Searching for nematicidal substances, it was evaluated themetabolic profile and the in vitro nematicial activity of leaf Annona crassiflora extract by mobility assay against the free-living nematode Caenorhabditis elegans. The species A crassiflora provided to be an auspicious source of new nematicidal substances. Finally, thepotential of 1H NMR in a quantitative and untargeted analysis was once again corroborated, allowing the identification and quantification of the betaine trigonelline, for the first time, in several species of Annona.