Unit:
Τομέας ΦΑΡΜΑΚΕΥΤΙΚΗΣ ΧΗΜΕΙΑΣLibrary of the School of Science
Dissertation committee:
Γκίκας Ευάγγελος Επίκ. Καθηγητής (Επιβλέπων), Σκαλτσούνης Αλέξιος-Λέανδρος Καθηγητής, Μητάκου Σοφία Καθηγήτρια,
Original Title:
Development of State-of-the-art mass spectrometry-based analytical methodologies for the study of bioactive natural products fate after dietary administration. Bioavailability, metabolism/metabolomics studies
Translated title:
Ανάπτυξη καινοτόμων αναλυτικών μεθοδολογιών στηριζόμενων σε φασματομετρία μάζας για τη μελέτη της μοίρας βιοδραστικών φυσικών προιόντων μετά τη χορήγηση τους μέσω τροφής. Βιοδιαθεσιμότητα, μεταβολισμός, μεταβολομικές μελέτες
Summary:
Flavonoids are a class of polyphenolic molecules present in food, such as
fruits, vegetables and plant derived juices. They represent one of the most
important classes of biologically active compounds.
In the present study the fate as well as the putative biochemical effects of
naringin and hesperidin was examined after their dietary supplementation in
Ross 308 broiler chickens, in order to increase the antioxidant capacity of
their tissues.
Two fully validated methodologies were developed for the simultaneous
quatitation of hesperidin, naringin, hesperetin and naringenin in plasma and
tissue samples. According to the results, in plasma samples only naringin
concentration levels were above the LLOQ after 30 days of administration
whereas in tissue samples no detectable amounts have been discovered.
Due to the low concentration levels of the analytes in plasma a High Resolution
Mass Spectrometry based metabolism study was performed in order to examine the
possibility of rapid and extensive metabolism. Two metabolite modifications
were detected for naringin, for naringenin and for hesperidin, respectively.
Nevertheless, no metabolite modification was detected for hesperetin.
Into the next step, the effect of the substances in the whole biochemical
profile of the organism has been investigated. Due to the complexity of such
analyses, novel data processing methologies have to be developed and validated.
In theis context, a new strategy in the data processing pipeline of MS based
metabolomics was developed with the aim to increase the number of the reliable
metabolite identifications. This methodology was applied to the untargeted
metabolomics study in chicken plasma samples that were administered either with
hesperidin or naringin for 30 days. Four variables were detected to
discriminate control group from the group after naringin administration whereas
only one substance could effectively discriminate the hesperidin treated from
the control group.vii
Additionally in order to further characterize the metabolic changes that occur
in tissues as a response to naringin and hesperidin dietary supplementation in
chickens, two metabolomics studies (for naringin and hesperidin) has been held.
Six variables were detected as discriminating naringin the dietary
supplementation group and twelve variables corrresponding hesperidin
supplementation group from their respective control group.
Keywords:
Mass spectrometry, Bioavailability, Metabolism, Metabolomics studies
Number of index pages:
iv-v
Number of references:
161
