الفهرس | Only 14 pages are availabe for public view |
Abstract The current thesis is divided into two studies as a part of our ongoing project. First we investigated the species visnaga with the objective to isolate, purify and structure elucidation the compounds as a part of our ongoing project for bioactivity direct fractionation of medicinal plants. Second to investigate the phytochemical, cytotoxic and antimicrobial properties exhibited by the bioactive compounds extracted from colonies of Egyptian soft coral Sarcophyton trocheliophorum. The present research work aims at:- 1. Isolation and purification of the bioactive compound(s). 2. Elucidation of the structure by mass spectrometry and details 1D and 2D NMR spectroscopy. 3. Screening the biological activity of the soft coral crude extracts using different bioassays. 4. Bioassay guided fractionation for isolating active ingredients emphases on cytotoxic and antimicrobial activity. The present study covered the following points: Chapter 1: Introduction and literature review 1st part: includes review of literature about natural products which contribute significantly to primary health care worldwide with focus on plant Ammi visnaga. 2nd part: includes review of literature about marine as natural sources and description of Soft corals S. trocheliophorum and their natural existence. Chapter 2: Experimental work 1st Part: Describes the apparatus and methods used for isolation, purification and identification of compounds from plant A. visnaga. 2nd Part: Includes extraction of marine materials used in the present study (S. trocheliophorum), and describes the methods used to test the cytotoxic and antimicrobial activities by using Brine shrimp lethality bioassay and growth inhibition activity by turbidity measurement method respectively. Chapter 3: Results and discussion 1st Part: Our investigation on plant A. visnaga leads to isolation of one chromone glycoside, along with two furano chromone and two flavonoid compounds. The structure elucidated by IR, one-and two-dimensional NMR, high-resolution mass spectrometry and comparison with spectroscopic data of closely related structures. 2nd Part: In the present study on the colonies of soft coral (S. trocheliophorum) cytotoxicity was evaluated using the brine shrimp lethality bioassay and antibacterial activity was evaluated against the pathogenic bacteria Bacillus cereus, Staphylococcus aureus, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa using the disk diffusion assay. The hexane extracts were more cytotoxic than the ethyl acetate extracts. Two fractions from the hexane extract and one from the ethyl acetate extract showed significant cytotoxic activity against brine shrimp nauplii. Moreover, two fractions of the hexane extract demonstrated good activity against S. aureus and B. cereus in zone of growth inhibition assays. One fraction of the ethyl acetate exhibited strong activity against E. coli and S. typhi. The results indicate that extracts from the studied soft coral contain bioactive compounds that could potentially prove useful in the development of anti-cancer drug leads and antibacterial agents. |