Thesis (MSc) - Cyprus International University. Institute of Graduate Studies and Research Environmental Science Department

Includes bibliography (sheets 39-47)

ABSTRACT Water is very important in terms of resources available for human advancement and life on the planet. The current study explores the antibacterial potentials of methanol and ethyl-acetate extracts of Chrysanthemum coronarium L. Roots, Leaves, and flowers on isolated coliform bacterial species from domestic wastewaters using growth inhibition indices based on the agar plate technique. The recovered percentage of the extracts was 15.52%, 16.38%, and 17.46% for methanol root, leave, and flower, 3.14%, 4.63%, and 6.15% for ethyl-acetate root, leave, and flower respectively, extracts were significantly (p ≤ 0.05) influenced by the various extraction solvents utilized. The capacity of various plant components to neutralize free radicals in the DPPH assay, root, leaf, and flower extracts prepared by two different extraction methods of Chrysanthemum coronarium was determined and compared to that of the reference ascorbic acid at various concentrations. The reaction of antioxidants in samples with the stable DPPH free radical was measured spectrophotometrically. DPPH radical scavenging activities were reduced in all of the investigated samples when compared with the standard of 98%. It was revealed that the extracts prepared by methanol showed more DPPH free radical scavenging activity with the root having 96% than the corresponding extracts prepared by ethyl acetate that had the least of 41% from the leaf. At different concentrations methanolic root extracts of Chrysanthemum coronarium showed the highest DPPH radical scavenging activity followed by the flower and leaf. For MIC the values were from 1000 to 250-μg/ml for both methanolic and ethyl-acetate extracts. 30-percent DMSO negative control had no effect on the tested microorganisms. The disc diffusion study indicated that methanolic extracts displayed more potency of antimicrobial activity as compared to ethyl-acetate, ciprofloxacin had the largest inhibition zone and was used as the positive control. Qualitative phytochemical activities of the extracts were also determined. Phytochemical analysis revealed plant extracts contained, saponins present in all plant parts, flavonoids only present in root and flower and absents in leaf in both extracts, tannins were only present in methanolic root extract, alkaloids were present in both leaf and flower but absent in root extracts, phenols which were only present in methanolic root extract but missing in both leaf and flower extracts, carbohydrates were also present in flower for both extracts. Methanolic extraction of C. coronarium can be utilized as an antibiotic means to fight coliform bacteria diseases in domestic wastewater. Keywords: Antibacterial, Antioxidant, Chrysanthemum coronarium, Coliform Bacteria, Phytochemicals, Wastewater.