Unit:
Department of PharmacyLibrary of the School of Science
Author:
Boka Vasiliki-Ioanna
Dissertation committee:
Professor Alexios-Leandros Skaltsounis, Department of Pharmacognosy and Natural Product Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens
Professor Sofia Mitakou, Department of Pharmacognosy and Natural Product Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens
Associate Professor Nektarios Aligiannis, Department of Pharmacognosy and Natural Product Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens
Assistant Professor Nikolaos Fokialakis, Department of Pharmacognosy and Natural Product Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens
Professor Evagelos Gikas, Department of Laboratory of Analytical Chemistry, Faculty of Chemistry, National and Kapodistrian University of Athens
Professor Jean-Luc Wolfender, School of Pharmaceutical Sciences, University of Geneva, Switzerland
Research Director Dimitrios Kletsas, Laboratory of Cell Proliferation & Ageing, Institute of Biosciences and Applications, National Centre for Scientific Research (NCSR) "Demokritos”
Original Title:
Exploitation of Greek flora for the discovery of antioxidant and skin-whitening natural compounds based on HPTLC and CPC techniques
Translated title:
Exploitation of Greek flora for the discovery of antioxidant and skin-whitening natural compounds based on HPTLC and CPC techniques
Summary:
The use of plants as medicines predates written human history. Many of the herbs and spices used by humans to season food also yield useful medicinal compounds. Nowadays, the use of herbs to treat diseases is almost universal among non-industrialized societies and the search for drugs and dietary supplements derived from plants have accelerated. Besides, in modern society, there is a great increase in research concerning aging and the necessity of finding ways to prevent or inhibit it. Specially, regarding antioxidants and whitening agents in skin care, products can now be viewed as active and beneficial as they contain “bioactives” which though not medicinal, are endowed with functional attributes. Greek flora is an excellent source for natural “bioactives”, as it consists of approximately 6700 species of which ca. 22% are endemic. Moreover, despite the rich diversity and importance, only a small proportion, approximately 10%, of the classified plants have been investigated and chemically characterized. The issue that comes up with the existence of such numbers is how to avoid laborious and time-consuming isolation of individual compounds. Lamiaceae family was investigated for antioxidative protective potential, aiming to the identification of promising plant sources for the direct discovery of lead secondary metabolites. Screenings were conducted by employing simple and rapid assays to support a high-throughput procedure based on HPTLC and FCPC. A hundrend and eighty plant (180) extracts were investigated for their antioxidant properties leading us to the final eleven (11) extracts. The 11 species and subspecies were further assessed for their antioxidant potential (ABTS, ROS), whereas the lead compounds of each extract were detected through HPTLC-autography. Further up, two procedures that would lead us in a short time to a small number of appropriate solvent systems for the FCPC procedure were established and the potent antioxidant natural compounds were isolated. For the discovery of NPs with skin whitening properties from Greek plant extracts there was an attempt to combine three High-Throughput Screening (HTS) techniques (NMR-Heterocovariance approach, HPTLC-Based activity profiling and HPTLC-autography) to establish an integrated high-throughput multivariate statistics platform. Eight extracts derived form plants of Greek flora (Armeria canescens, Cercis siliquastrum, Pistacia terebinthus, Paeonia mascula ssp hellenica, Paeonia clusii ssp. clusii, Veratrum album, Cistus salvifolius and Sedum sediforme) were chosen and investigated by means of high-throughput multivariate statistics platform to detect and identify potent natural compounds with whitening activity prior any isolation.
Main subject category:
Science
Other subject categories:
Health Sciences
Keywords:
Antioxidant activity, Skin-whitening, High Performance Thin Layer Chromatography (HPTLC), High Speed Counter Current Chromatography FCPC, Multivariaty Statistics
Number of index pages:
163
Number of references:
313
File:
File access is restricted until 2025-12-13.
PhDBoka.pdf
13 MB
File access is restricted until 2025-12-13.
