Bioengineering / Biyomühendislik
Permanent URI for this collectionhttps://hdl.handle.net/11147/4529
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Article Citation - WoS: 4Citation - Scopus: 5Antioxidant and Antimicrobial Activities of Plants Grown in the Mediterranean Region(John Wiley and Sons Inc., 2022) Kaçar, D.; Bayraktar, Oğuz; Erdem, C.; Alamri, A.S.; Galanakis, C.M.Background: The main objective of this research was to identify plant species with possible bioactivities based on their total phenol content, antioxidant, and antimicrobial properties. Therefore, different parts of 42 plant species grown in the Mediterranean region were extracted with aqueous ethanol solutions to prepare extracts with antioxidant and antimicrobial activities, mainly resulting from their total phenol contents. No detailed laboratory data on the flora of this area exists regarding their total phenol contents and total antioxidant activities. Results: Yields of extraction for each plant material were determined. Extracts were characterized based on their total phenol contents, total antioxidant (both hydrophilic and lipophilic), and antimicrobial activities using Folin–Ciocalteu, Photochemiluminescence, disc diffusion, and microdilution methods, respectively. The extract of Hypericum empetrifolium had the relatively highest total water-soluble and lipid-soluble antioxidant activities. Sarcopoterium spinosum extract had relatively high total phenol content. Preliminary screening study was conducted with the disc diffusion method to evaluate the extracts' antimicrobial activities. 26 out of 42 plant species showed significant antimicrobial activities against the growth of microorganisms. Microdilution assays were performed to evaluate the most active plant species with their minimum inhibition concentrations. H. empetrifolium, Pistacia terebinthus, Arbutus unedo, and Cistus parviflorus were the most antimicrobial plant species among those investigated. CONCLUSION: The new potential sources for the isolation of bioactive natural compounds from specific plant species could be possible with the help of this present screening study. Isolated bioactive natural compounds can be utilized as raw materials in cosmetics, nutraceuticals, food supplements, and pharmaceutical industries. © 2022 Society of Chemical Industry.Article Citation - WoS: 2Citation - Scopus: 2Transition-Metal Direct C-H Arylation of Thiophene in Aqueous Media Via Potassium Peroxymonosulfate(John Wiley and Sons Inc., 2019) Özenler, Sezer; Kaya, Hakan; Elmacı, Nuran; Yıldız, Ümit HakanThis study covers the use of potassium peroxymonosulfate (PPS) which, is a mild and inexpensive catalyst, for direct coupling of C-H/C-H for water soluble thiophene. The 3-(4-methyl-3 '- thienyloxy)propyltriethylammonium bromide (M1) has been selected as model monomer that reacted PPS in 2.0, 0.20 and 0.020 monomer to PPS ratio. The reaction has been monitored via NMR spectroscopy revealing the monomer consumption and formation of dimers to tetramers as well as completion of reaction within 15 minutes. Resultant product is easily collected without tedious work up steps. The computational calculation has optimized the regularity of the coupling as head to tail, tail to tail, head to tail (HT-TT-HT) for tetramer. The regularity of tetramer which is further satisfied via NMR analysis showing emergence of new peaks at 3.56 and 4.48. The shifts in the UV maximum of reactive species have been monitored by absorbance spectroscopy showing time dependent red shift corresponds to growing from monomer to tetramers. The reaction has self-stopped due to low solubility of moderate condensates (higher than trimer), however further experiments have performed in water-organic mixtures showed great promises to obtain higher condensates.