M.Sc. Tezi Görüntüleme

Student:	Şehriban BAYRAKTAR
Supervisor:	Prof. Dr. Atalay SÖKMEN
Department:	Biyoloji
Institution:	Graduate School of Natural and Applied Sciences
University:	Karadeniz Technical University, Turkey

Title of the Thesis:	An Investigation on the Antimicrobial and Antioxidant Activities of Some Asteraseae and Umbelliferae Species
Level:	M.Sc.
Acceptance Date:	15/7/2009
Number of Pages:	71
Registration Number:	i2043

Summary:

This study was designed to carry out the in vitro antioxidant and antimicrobial activities of hexane, chloroform and water extracts as wells as the essential oils obtained from Artemisia annua (L.), Matricaria matricarioides (Less.) Porter ex Britton and Laser trilobum (L.) Borkh.

The oils and extracts were screened for their possible antioxidant activities by two complementary test systems, namely 1,1-Dipheniyl-2-Picrylhydrazyl (DPPH) free radical scavenging and β-Carotene color bleaching test – spectrophotometric methods. In DPPH, all polar extracts acted as radical scavengers on high proportions. With β-Carotene method it was seen that all extracts % relative antioxidant activity (% BAA) rates were high enough to be compared with that of synthetic antioxidant, BHT.

By following the protocols given by NCCLS (National Committee for Clinical Laboratory Standards), the in vitro antimicrobial (antibacterial and anticandidal) activities of the extracts and the essential oils were determined by using agar well diffusion, disc diffusion (for the latter), broth microdilution and agar dilution methods. Six bacteria and four yeasts were used as test microorganisms. In general, no activity was found in the polar extracts, whilst hexane extracts as well as the essential oils showed a remarkable antibacterial and anticandidal activity.

The chemical substances of essential oils were determined by employing Gas chromatography-mass spectrometry (GC-MS) and Gas chromatography- flame ionization detector (GC-FID) analyses. Geranyl valerate (% 34,9) and E-β-Farnesene (% 23.3); Artemisia ketone (% 18,9), Camphor (% 13,7) and 1,8- Cineole (% 10.2); and Perillaldehyde (%73.0) were the main components of the essential oils of Matricaria matricarioides, Artemisia annua and Laser trilobum, respectively.

Key Words: Artemisia annua, Matricaria matricarioides, Laser trilobum, antimicrobial activity, antioxidant activity, essential oil, GC-MS, GC-FID.