Characterization of antioxidant and antimicrobial isolates from Quercus brantii L. extract

Nebigil, Can
This study was designed for the investigation of antioxidative, and antimicrobial properties of Quercus brantii L. (Q.brantii.) seed extract. Phenolic profile of the total extract was determined by using High Performance Liquid Chromatography (HPLC) and confirmed by High Resolution Mass Spectroscopy (HRMS). Solvent fractionation was performed to seperate bioactive compounds in total extract by using solubility differences. In comparison of fractions, ethyl acetate and diethyl ether phases have revealed highest antioxidant effect. Due to the low yield and high number of the molecules in ethyl acetate fraction, HRMS was used to characterize the compounds. On the other hand, in diethyl ether fraction, there was a single major compound which showed high antioxidant activity. The major compound, was purified by column chromatography and characterized by NMR, IR and HRMS as methyl gallate. E.coli, P.mirabilis, S.aureus, S.pyogenes bacterial strains were used to determine the antimicrobial activity of Q. brantii seed crude extract, fractions and isolated compound by disc diffusion, MIC and MBC methods. Isolated methyl gallate and ethyl acetate fraction displayed a significant effect on all bacterial strains as high as reference antibiotics. Consequently, crude Q. branti extract, isolated methyl gallate and ethyl acetate fraction could be considered as powerful antimicrobial agents, and at the same time efficacious antioxidants.


Characterization and Evaluation of Triamcinolone, Raloxifene, and Their Dual-Loaded Microspheres as Prospective Local Treatment System in Rheumatic Rat Joints
Ocal, Yigit; Kurum, Baris; Karahan, Siyami; Tezcaner, Ayşen; Ozen, Seza; Keskin, Dilek (Elsevier BV, 2014-8)
In this study, injectable microspheres were developed for the local treatment of joint degeneration in rheumatoid arthritis (RA). Microspheres loaded with triamcinolone (TA), a corticosteroid drug, and/or raloxifene (Ral), a cartilage regenerative drug, were prepared with a biodegradable and biocompatible polymer, polycaprolactone (PCL). Microspheres were optimized for particle size, structural properties, drug release, and loading properties. In vitro release of Ral was very slow because of the low solubil...
Characterization of Novel O-Glycans Isolated from Tear and Saliva of Ocular Rosacea Patients
Özcan Kabasakal, Süreyya; Vieira, Ana C.; Park, Gun Wook; Kim, Jae Han; Mannis, Mark J.; Lebrilla, Carlito B. (American Chemical Society (ACS), 2013-03-01)
O-Glycans in saliva and tear isolated from patients suffering from ocular rosacea, a form of inflammatory ocular surface disease, were profiled, and their structures were elucidated using high resolution mass spectrometry. We have previously shown that certain structures, particularly sulfated oligosaccharides, increased in the tear and saliva of rosacea patients In this study, the structures of these glycans were elucidated using primarily tandem mass spectrometry. There were important similarities in the ...
Kalyoncuoglu, Ulku Tugba; Yilmaz, Bengi; Gungor, Serap; Evis, Zafer; UYAR, PEMBEGÜL; AKCA, GÜLÇİN; Kansu, Gulay (2015-01-01)
The aim of this study was to obtain a biocompatible and antimicrobial implant surface by coating Ti6Al4V with chitosan which can be used to create a smooth transmucosal region for a faster and better wound healing and an increased bioactivity. Ti6Al4V plates were first abraded and ultrasonically cleaned and then coated with chitosan. In order to simulate the conditions of an oral environment, a group of coated plates were treated in a thermocycle apparatus. The coatings were evaluated with SEM, EDS, XRD and...
Characterization of extracellular beta-lactamases from penicillin G-resistant cells of Streptococcus thermophilus
Chirica, LC; Güray, Nülüfer Tülün; Gültekin, Güzin Candan; Bozoglu, F (International Association for Food Protection, 1998-07-01)
In this study, biochemical properties of two extracellular beta-lactamases produced by penicillin-resistant Streptococcus thermophilus cells were investigated. Both beta-lactamases showed specificity for penicillins but not for cephaloridins. The p-lactamases exhibited different affinities for penicillin G. The one with the higher molecular weight (F1) had a K(m) value of 3.44 mu M and a V(max), value of 8.33, mu mol/min/mg of protein, whereas the beta-lactamase with the lower molecular weight (FII) had a K...
Investigation and scale-up of hot-melt coating of pharmaceuticals in fluidized beds
Külah, Görkem (Elsevier BV, 2011-03-10)
This study was performed to investigate and scale-up the hot-melt coating process in fluidized beds. A series of well-designed experiments was carried out in a pilot scale unit with 20 kg product capacity to investigate the effects of process variables on the efficiency of the coating of Cefuroxime Axetil with stearic acid. Results showed that the efficiency is at the highest when the fluidization air flow rate is adjusted by considering the changes in the amount of materials present in the unit as well as ...
Citation Formats
C. Nebigil, “Characterization of antioxidant and antimicrobial isolates from Quercus brantii L. extract,” M.S. - Master of Science, Middle East Technical University, 2011.