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Objectives Natural products are often efficacious and safe alternatives to synthetic drugs. This study explored secondary leaves and bark metabolites profiles in extracts of a new Egyptian hybrid, Annona cherimola × Annona squamosa, known as Abdel Razek. This hybrid exhibited 100% similarity with A. cherimola as evidenced by random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses. Methods Primary constituents in methanol extracts of different plant organs were identified. Extracts richest in alkaloids and polyphenolics were assessed for in vitro antioxidant activity and the most potent were further studied in vivo for treating gastric ulcer in rats. The latter activity was assessed histopathologically. Results Structural analysis with HPLC/ESI-MSn, and UPLC/HESI-MS/MS identified 63 metabolites, including seven amino acids, 20 alkaloids, 16 flavonoids, eight phenolics and other compounds. Severe stomach alteration was observed after ethanol induction in rats. Ulcer score, oxidative stress biomarkers, cell organelles biomarker enzymes, and gastrointestinal histological features improved to variable degrees after treatment with Annona Abdel Razek hybrid leaves and bark methanol extracts. Conclusion Extracts of Annona Abdel Razek had showed in vitro antioxidant effect and may be promising for the treatment of gastric ulcers. Graphical abstract

Flavones and isoflavones are a major group of phenolic secondary metabolites which occur in leaves of narrow leafed lupine (Lupinus angustifolius) either as free aglycones or in a form of glycosides and malonyl-glycosides. Profiles of phenolic compounds in leaves of seedlings infected with anthracnose causing fungus Colletotrichum lupini were compared to those of healthy plants. A HPLC with diode array UV detector was used as the analytical method and identification of these secondary metabolites was confirmed with a HPLC/MSn instrument. Isomers of several target compounds differing in the glycosilation and/or malonylation pattern were detected in the studied samples. However, the application of standard HPLC with C18 columns resulted in the co-elution of several glyconjugates in single chromatographic peaks whereas for isoflavonoid aglycones complete resolution was achieved. Lupine plants grown in a greenhouse were either sprayed with the C. lupini spore suspension or the suspension was spotted on to wounded leaves. Profiles of the isoflavones were altered in result to infection with both methods. In particular, the concentration of isoflavone free aglycones detected in extracts from diseased plants was substantially increased in all of the studied samples. However, the pattern of these compounds depended on the age of lupine leaves as well as on the method of infection. Synthesis of luteone and 2′-hydroxygenistein was enhanced in the youngest leaves of plants sprayed with spores as well as in wound-infected leaves. Wighteone synthesis was induced mainly in older leaves of plants sprayed with the spore suspension.

Lupine (Lupinus spp.) is one of the crop plants from the Fabaceae family cultivated on a moderate scale in Europe, Australia and South America; however, its cultivation suffers from a severe fungal disease anthracnose caused by Colletotrichum lupini fungus. The search for resistant plant genotypes as well as methods of plant immunization against such infections is of importance. Plant interaction with pathogenic microorganisms results in complex regulation of many biochemical and physiological processes. Activation of expression of defence genes that leads to the induction of bioactive secondary metabolites biosynthesis is among them. The aim of the presented work was to investigate changes in the isoflavonoids quantities as the reaction of narrow leaf lupine (Lupinus angustifolius) plants growing in the field conditions to infection with the pathogenic fungus (C. lupini) or treatment with its phytotoxic metabolites followed after 48 h with infection with the fungus. The metabolic profiling after field experiments revealed variety-specific changes of these compounds. Elicitation of plants with fungal phytotoxin prior to infection resulted in higher levels of prenylated isoflavones, especially phytoalexins luteone and wighteone and their various glycoconjugates in comparison to those observed in plants infected only with the fungal spores. The metabolomic analyses were supported by the transcriptomic view of genes involved in isoflavonoids biosynthesis. Infection of Lupinus angustifolius by Colletotrichum lupini combined with former elicitation of plants results in accumulation of prenylated isoflavonoids and change in the isoflavone prenyltransferase gene expression pattern.

Deciphering of the plant metabolome is one of the most difficult analytical tasks in functional genomic research. Studies directed at the gene or protein expression are well established, sequencing analyses of these kinds of biopolymers on genome or proteome level are possible. This is not the case for metabolites, where identification in single sample of many chemical entities of different elemental composition and structures and various physicochemical properties is necessary. Different instrumental methods are applied for identification of metabolites but none of them allows obtaining unambiguous structural information about more than 500 compounds in single mixture (metabolite profiling). This is a much smaller number of metabolites than is predicted for single plant metabolome. However, instrumental approaches were proposed (metabolite fingerprinting) in which biochemical phenotype of an organism may be estimated, but identification of individual compounds is not possible.