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Identifier

000414225

Title

Μεταβολομική ανάλυση φυτικών εκχυλισμάτων και βιολογικών υγρών με τη φασματοσκοπία NMR

Alternative Title

Metabolomic analysis of plant extracts and biological fluids by nuclear magnetic resonance spectroscopy

Author

Μανωλοπούλου, Ευσταθία Κων

Thesis advisor

Σπύρος, Απόστολος

Reviewer

Περγαντής, Σπυρίδων
Στεφάνου, Ευριπίδης

Abstract

Τhis dissertation uses NMR-based metabolomics and chemometric methods for the analysis of several extracts of plant origin (olive oil mill water condensates, spearmint extracts, olive leaves) and biological fluids (culture media, rat urine and human blood plasma). A novel spectroscopic “standardless” analytical NMR methodology that does not necessitate the use of an internal quantification standard, qEretic2, was developed and validated for the quantification of olive leaf metabolites. This methodology was applied for the metabolite/phenolic profiling of olive leaves obtained from trees of two different cultivars (Picual, Koroneiki) as a function of leaf harvest time, resulting in the successful classification of leaves of different cultivar, while harvest time was found to also have an effect on the phenolic content of the leaves. The qualitative and quantitative characterization of olive oil mill water condensates and spearmint extracts by NMR spectroscopy was conducted in order to aid their use as phenolic antioxidant additives in functional foods. NMR analysis showed that plant origin and year of production have a significant effect on the type and quantity of bioactive and phenolic compounds present in these plant-derived extracts. The effect of olive oil mill water condensates and spearmint extracts as encapsulated antioxidant additives of functional foods on metabolism was studied in three separate studies (a) HepG2 cell cultures during cell growth, (b) an animal model utilizing the NMR-based urine analysis after acute administration of encapsulated extracts in high fat-fed rats, and (c) two clinical studies using healthy volunteers that adhered to a specific diet that included administration of microencapsulated extracts in functional foods (pariza, meat product containing an olive oil mill water condensate and yoghurt containing a spearmint extract). Multivariate statistical model analysis demonstrated the temporal changes in the metabolite profile of rat urine and the effect of bioactive compounds present in the two plant extracts. The analysis of the metabolite and blood plasma lipid profile of healthy volunteers demonstrated an extract type-dependant metabolic effect of the encapsulated components of the functional foods, in agreement with clinical biochemical blood markers (glucose, LDL-HDL cholesterol). The metabolic effect due to the consumption of the functional food was more pronounced in volunteers with at least two biochemical or anthropometric elements of cardio-metabolic risk. Finally, the NMR-obtained metabolite dataset was analysed using Metaboanalyst 3.0 in order to elucidate the metabolic pathways involved in the metabolite profile changes observed during the cell culture media, animal model and healthy volunteer studies. It was found that similar metabolic pathways were involved in all three cases after administration of the same plant-derived extract.

Language

Greek

Subject

1H-NMR spectroscopy

Metabolic pathways

Plant extracts

qEretic2

Βιολογικά δείγματα

Μεταβολίτες

Μεταβολικά μονοπάτια

Φυτικά εκχυλίσματα

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