Study of the chemical composition and bioactivity of the secretion of the Helix aspersa

Postgraduate Thesis uoadl:2683531 372 Read counter

Unit:
Κατεύθυνση Φαρμακογνωσία βιοδραστικών φυσικών προϊόντων
Library of the School of Science
Deposit date:
2018-03-05
Year:
2018
Author:
Papakonstantinou Aikaterini
Supervisors info:
Μαγιάτης Προκόπιος, Αναπληρωτής Καθηγητής, Τμήμα Φαρμακευτικής, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Original Title:
Μελέτη της χημικής σύστασης και της δράσης της βλέννας του σαλιγκαριού Helix aspersa
Languages:
Greek
Translated title:
Study of the chemical composition and bioactivity of the secretion of the Helix aspersa
Summary:
The main subject of this thesis is the study of the chemical composition of secretion of the Helix aspersa, the small molecule isolation and identification and the development of quantitative analytical methods. Moreover, during this study a small scale clinical trial was conducted regarding the effect of snail mucus on the skin, and more specifically its benefits on skin hydration and antiaging. The ultimate goal is the use of snail mucus in cosmetic creams.
The first part of the thesis refers to some general information about snails and especially the Helix aspersa species and its two subspecies (Helix aspersa muller and Helix aspersa maxima). Particularly, it presents the snail’s general features, classification and their therapeutic usage since antiquity. Next, it gives a deeper insight on the snail mucus chemical composition and its effect on the skin according to literature study. In the last section of this part, the chemical properties and the biological role of the main substances (trimethylglycine, allantoin and glycolic acid) are described as well as some methods for their quantification.
In the second part, the whole experimental procedure is presented. Initially, a general investigation of snail mucus is performed by Nuclear Magnetic Resonance (NMR) spectroscopy and the analytical method is then set up. The next section includes the isolation and identification of four substances by column chromatography, of which trimethylglycine is isolated for the first time from snail mucus. Moreover, the NMR spectroscopy data for allantoin is elucidated, and then the isolation and identification of the ionized form of allantoin. It is first isolated from snail mucus and described by NMR spectroscopy. In addition, glycolic acid are detected in snail mucus and after analysis of mucus by gas chromatography 11 substances were detected in small amounts. Furthermore, a method is developed for the simultaneous quantification of trimethylglycine and the ion of allantoin by NMR spectroscopy, while another method is set up for quantification of glycolic acid by GC-MS. Glycolic acid levels measured by GC-MS were much lower, in comparison with an equivalent method by HPLC described in literature. Finally, a small scale clinical trial is conducted concerning the beneficial effects of snail mucus on skin’s health.
Main subject category:
Science
Other subject categories:
Health Sciences
Keywords:
secretion, Helix aspersa, allantoin, glycolic acid, trimethylglycine
Index:
No
Number of index pages:
0
Contains images:
Yes
Number of references:
149
Number of pages:
135

Παπακωνσταντινου- Master.pdf
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