Unit:
Department of BiologyLibrary of the School of Science
Author:
Chantzistrountsiou Xanthi
Dissertation committee:
1. Αθηνά Οικονόμου-Αμίλλη, Ομότιμος Καθηγήτρια, Τμήμα Βιολογίας, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
2. Χρήστος Κατσαρός. Ομότιμος Καθηγητής, Τμήμα Βιολογίας, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
3. Αριστείδης Παρμακέλης, Αναπληρωτής Καθηγητής, Τμήμα Βιολογίας, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
4. Μαρία Μουστάκα, Καθηγήτρια, Τμήμα Βιολογίας, Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης
5. Δημήτριος Χατζηνικολάου, Αναπληρωτής Καθηγητής, Τμήμα Βιολογίας, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
6. Εμμανουήλ Φλεμετάκης, Καθηγητής, Τμήμα Βιοτεχνολογίας, Γεωπονικό Πανεπιστήμιο Αθηνών
7. Διονύσιος Ε. Ραΐτσος, Επίκουρος Καθηγητής, Τμήμα Βιολογίας, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Original Title:
Συστηματική και Οικολογία Μικροφύκων από παράκτια Μεταβατικά Οικοσυστήματα της Δυτικής Ελλάδος (Ιονίου)
Translated title:
Systematics and Ecology of Microalgae from Coastal Transitional Ecosystems of Western Greece (Ionian Sea)
Summary:
This doctoral thesis focuses on the study of microalgal strains of characteristic phytoplankton groups of ecological and taxonomic interest isolated from transitional aquatic ecosystems of W. Greece, through a multivariate approach. Meanwhile, their potential utilisation in an applied level. Strains isolated from the lagoonal system of Messolonghi-Aetoliko as well as strains already deposited in the micoralgae Strain Bank AthU-Al of the N.K.U.A, originating from several coastal lagoons of Greece, were studied herein. The studied organisms include five strains of the genus Tetraselmis and 25 strains that show affinity for the species Dunaliella salina. The Tetraselmis strains were studied using methords of classic taxonomy (light and electron microscopy), methods of molecular phylogeny and biochemical methods of fatty acid profile analysis. The D. salina strains were studied using methods of classic taxonomy as well as biochemical methods. The latter involved two series of experiments of incresed salinity stress in order to investigate the efect of salinity on the production of β-carotene in the strains’ cells and to evaluate their potential use in industrial applications.The Tetraselmis strains were classified in the species Tetraselmis verrucosa f. rubens and presented an interesting intra-specific diversity, displaying differences in both morphology as well as biochemistry. The D. salina were re-named as D. cf. salina due to the controversial results of their taxonomic analysis. A re-evaluation of the taxonomic system for the halophilic species of the genus Dunaliella using biochemical criteria, wes perfomed based on the said results; these criteria seem to be inefficient in the incontrovertible distinction between different Dunaluella species, however they are an important distinction criterion in an intra-specific level. The results of the salinity experiments as well as the morpholigal obserdvations support the polymorphic natur of the species D. salina and additionally accent the potential suitability of some of the studied strains for use in the β-carotene production industry.The results of the present thesis as well as their evaluation, reveal the intra-specific diversity of cultured populations of phytoplankters originating from transitional waters, in a taxnomic, ecological and biochemical level, as well as the necessity for re-evaluation and improvement upon the existing taxonomic systems used for the study of these organisms, with the application of multivariate approaches including classic, molecular and biochemical methods, which allow the full characterisations of the studied strains as well as their potential exploitation in an industrial scale.
Main subject category:
Science
Keywords:
Microalgae, Taxonomy and ecology of microalgae, Tetraselmis, Dunaliella, Beta-carotene, Transitional ecosystems, Multivariate systematic approach
Number of references:
954
