Unit:
Τομέας ΦΑΡΜΑΚΟΓΝΩΣΙΑΣ ΚΑΙ ΧΗΜΕΙΑΣ ΦΥΣΙΚΩΝ ΠΡΟΪΟΝΤΩΝLibrary of the School of Science
Author:
Μπαβέλα Σταματίνα
Supervisors info:
Νεκτάριος Αληγίαννης Επίκ. Καθηγητής (Επιβλέπων), Αλέξιος-Λέανδρος Σκαλτσούνης Καθηγητής, Νικόλαος Φωκιαλάκης Επίκ. Καθηγητής
Original Title:
Φυτοχημική μελέτη εκχυλισμάτων του είδους Amelanchier parviflora subsp. chelmea και αξιολόγηση της επίδρασης τους στην διαδικασία της αγγειογένεσης
Translated title:
Phytochemical analysis of Amelanchier parviflora subsp. chelmea and bio-guided identification of the anti-angiogenic compounds
Summary:
Plants of genus Amelanchier (Rosaceae) have been characterized by significant
presence of anthocyanins, flavonoids and terpenoids[1]. A. parviflora subsp.
chelmea is a Greek endemic plant without phytochemical references and both
their EtOAc and MeOH extracts of the aerial part were evaluated for their
angiogenetic properties using endothelial cell-based functional assays[2]. The
results showed that both extracts exhibited important inhibition of endothelial
cell proliferation with 6.54% at 20 μg/ml for the EtOAc extract and 54.4% at 20
μg/ml for the MeOH extract.
In this study the phytochemical analysis of the extracts was achieved in two
steps. Initially the extracts were fractionated by step-gradient FCPC and
subsequently the chosen fractions were further purified using other
chromatographic techniques. The result of our study was the isolation of 36
natural compounds, six of which are flavonoids, nine triterpenes and sterols,
five phenolic compounds, three biphenyls, two lignans, five hydroxycinnamic
esters of triterpenes and six hydroxycinnamic esters of fatty alcohols. It is
important to say that the compounds 4-hydroxy-2΄,3,4΄,5,5΄-penta-methoxy
biphenyl, 3-hydroxy-2΄,4,4΄,5,5΄-penta-methoxy biphenyl and 2΄΄,4΄΄-
dimethoxy-sorlanine are new natural products. The identity of isolated
compounds was confirmed by NMR and MS spectroscopy.
Moreover, the FCPC fractions were evaluated for their ability to inhibit or
induce angiogenesis and the active fractions were selected in order to detect
their bioactive components. Subsequently, the evaluation of isolated compounds
with endothelial cell-based functional assays demonstrated that betulinol, 3-β-
O-trans-p-hydroxy-cynnamoyl-betulinol and 3-β-O-trans-caffeoyl-betulinic acid,
possess significant anti-proliferative activity with 64.9%, 66.7% and 38.9%
inhibition at 100 uM respectively. The bioactive compounds will be evaluated in
advanced in vitro and in vivo models to establish their anti-angiogenic
effects.
Keywords:
Angiogenesis, Fytochemistry, Secondary metabolites, Greek flora, Natural products
Number of index pages:
x-xi
Number of references:
189
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