Person: DEMİRKAN, ELİF
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DEMİRKAN
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ELİF
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Publication Investigation of effects of protease enzyme produced by Bacillus subtilis 168 E6-5 and commercial enzyme on physical properties of woolen fabric(Taylor, 2019-06-04) Demirkan, Elif; Kut, Dilek; Sevgi, Tuba; Doğan, Meral; Baygın, Eren; DEMİRKAN, ELİF; KUT, YAŞAR DİLEK; SEVGİ, TUBA; Doğan, Meral; Baygın, Eren; Bursa Uludağ Üniversitesi/Fen-Edebiyat Fakültesi/Biyoloji Bölümü; Bursa Uludağ Üniversitesi/Mühendislik Fakültesi/Tekstil Mühendisliği Bölümü; 0000-0002-5292-9482; 0000-0002-9059-0838; 0000-0002-7528-9529; AAG-7112-2021; AAH-4335-2021; ABI-4472-2020; CMN-9718-2022; CFF-0023-2022Wool is one of the most important fibers in textile industry, and has been commonly used for producing value added products due to its properties of lightness, warmth, softness, and smoothness. However, the special scale structure in wool cuticle can cause felting shrinkage of wool fabrics. Proteases have been widely used to modify the surface of wool to prevent wool felting, due to their ability to catalyze the hydrolysis of peptide bonds in wool scales. Although the treatment of wool with proteases was considered as an environmentally friendly technique to provide wool fabrics with shrink resistance properties, proteases exhibited low efficacy in removing the cuticle scales because of the highly cross-linked barriers. In this study, wool fabric was treated with protease enzyme obtained from novel isolated bacteria and commercial protease enzyme, and the results were compared. The tear strength, pilling changes in Delta E values, whiteness and yellowness values of wool were controlled. Results showed that treatment with Bacillus subtilis 168 E6-5 protease enzyme yielded improvements in the physical properties of wool fabric compared with commercial enzyme.Publication Evaluation of the effects of temperature, light, and UV-C radiation on HSP70A expression in chlamydomonas reinhardtii(Tübitak Bilimsel ve Teknolojik Araştırma Kurumu, 2021-01-01) Sevgi, Tuba; Demirkan, Elif; SEVGİ, TUBA; DEMİRKAN, ELİF; Bursa Uludağ Üniversitesi/Fen-Edebiyat Fakültesi/Biyoloji Bölümü; 0000-0002-5292-9482; 0000-0002-7528-9529; AAG-7112-2021; ABI-4472-2020In this study, various physical parameters (temperature, light intensity and UV-C radiation) which could be effective in heat shock response on C.reinhardtii by using molecular tools were investigated. In total, 256 transformants were obtained, among them, 160 transformants had continuous expression while 96 of them had heat-inducible expression. In these transformants, arylsulfatase activities were detected qualitatively and quantitatively. The best two transformants were selected and used in studies. To determine the effect of temperature, the cells were shifted from 23 degrees C to 35 degrees C, 37 degrees C, 40 degrees C and 42 degrees C. The heat shock response was induced at all temperatures. In investigating the effect of light intensity, 0, 14, 28, 70, 140 mu mol E.m(-2)s(-1) were used. It was found that the light intensity of 28 mu mol E.m(-2)s(-1) and above increased ARS activity. On the other hand, ultraviolet C radiation application was carried out for periods of 2, 6 and 12 h, and no significant change in ARS activity was observed. In order to compare the selected arylsulfatase activity results in the study, real-time polymerase chain reaction trials were conducted at the transcript level, and parallel results were obtained. As a result of the study, it was determined that the heat shock response was triggered by temperature and light intensity. These might be also important for plant stress and ecological studies.Publication In vitro evaluations of antioxidant, antimicrobial and anticancer potential of phytolacca americana l. (pokeweed) seed extract(Trakya Univ Balkan Yerlesesi Enstituler Binasi, 2022-10-01) Çetinkaya, Aynur Aybey; DEMİRKAN, ELİF; YILDIZ, GAMZE; ERTÜRK, ELİF; SEVGİ, TUBA; Bursa Uludağ Üniversitesi/Fen Edebiyat Fakültesi/Biyoloji Bölümü.; Bursa Uludağ Üniversitesi/Sağlık Uygulama ve Araştırma Merkezi.; 0000-0002-5292-9482; 0000-0003-2743-9745; AAG-7112-2021; JQI-3400-2023In this study, different parts of Phytolacca americana L. (Pokeweed) fruit from Turkiye were investigated for their antioxidant, antibacterial, antibiofilm and anticancer potentials. The radical scavenging activities, reducing power and total phenolic content were determined to appraise of the antioxidant potentials. The antibacterial and antibiofilm activities of the extracts against Enterococcus faecalis, Yersinia enterocolitica, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium were evaluated by using agar-well diffusion, minimum inhibitory concentration (MIC) and biofilm inhibitory concentration (BIC) assays. In addition of latening the onset of apoptosis depending on dose, the potential of the anti-proliferative effects was investigated on MDA-MB-231 and MCF-7 cells. The highest free radical scavenging activity and phenolic content were found in the seed extract. Seed extract showed the highest inhibition zones and significant antibacterial activity at 2.5-5 mg/mL MIC concentrations against tested bacterial strains. More significantly, seed extract was found effective on inhibition of early phase biofilm formation at 2.5-10 mg/mL. BIC concentrations against tested bacterial strains. Next, the main mechanisms of cell death of the seed extract in MDA-MB-231 and MCF-7 cells were investigated. Accordingly, when apoptosis was evaluated morphologically, late apoptosis was observed in cells that showed both Hoechst 33342 and Propidium Iodide (PI) positivity in a dose-dependent manner. This study showed that P. americana seed extract can contribute to alternative medicine studies and have potential power in pharmaceutical industry.Publication Lipase from new isolate bacillus cereus ATA179: Optimization of production conditions, partial purification, characterization and its potential in the detergent industry(Tübitak Bilimsel ve Teknolojik Araştırma Kurumu, 2021-01-01) Demirkan, Elif; Aybey Çetinkaya, Aynur; Abdou, Maoulida; DEMİRKAN, ELİF; Aybey Çetinkaya, Aynur; Abdou, Maoulida; Bursa Uludağ Üniversitesi/Fen-Edebiyat Fakültesi/Biyoloji Bölümü; 0000-0002-5292-9482; 0000-0003-2743-9745; ABI-4472-2020; CJN-1872-2022; CAU-1487-2022In this study, 341 Bacillus sp. strains were isolated from agricultural soils of Turkey. The potent extracellular lipase producer was selected. It was identified by 16S rRNA, named as Bacillus cereus ATA179. Optimal nutritional and physical parameters for lipase production were determined. Sucrose as the carbon source, (NHIHPO, as the nitrogen source, CaCl2 as the metal ion were obtained. The best results of physical parameters were stated at 45 degrees C, pH 7.0, shaking rate 50 rpm, inoculation amount 7% and inoculum age 24 h. ATA179 strain showed a 51% increase in enzyme production in the modified medium created by optimizing nutritional and physical conditions. Optimum pH value and temperature were found as 6.0 and 55 degrees C, respectively. CaCl2, Tween 20, Triton X-100 had an activating effect on enzyme activity. V-max and K-m kinetic values were found as 18.28 U/mL and 0.11 mM, respectively. The molecular weight was determined as 47 kDa. Lipase was found to be stable up to 75 days at -20 degrees C. The potential of the enzyme in detergent industry was also investigated. It was not affected by detergent additives, but was found to be effective in removing oils from contaminated fabrics. This new lipase may have potential to be used in detergent industry.Publication Effects of psychotropic drugs as bacterial efflux pump inhibitors on quorum sensing regulated behaviors(Slovak Univ Agriculture Nitra, 2014-08-22) Aybey, Aynur; Usta, Alev; Demirkan, Elif; Aybey, Aynur; Usta, Alev; DEMİRKAN, ELİF; Uludağ Üniversitesi/Fen-Edebiyat Fakültesi/Biyoloji Bölümü.; 0000-0003-2743-9745; 0000-0002-5292-9482; ABI-4472-2020; CJN-1872-2022; GFJ-9415-2022Psychotropic drugs are known to have antimicrobial activity against several groups of microorganisms. The antidepressant agents such as duloxetine, paroxetine, hydroxyzine and venlafaxine are shown to act as efflux pump inhibitors in bacterial cells. In order to the investigation of the effects of psychotropic drugs were determined for clinically significant pathogens by using standart broth microdillusion method. The anti-quorum sensing (anti-QS) activity of psychotropic drugs was tested against four test pathogens using the agar well diffusion method. All drugs showed strong inhibitory effect on the growth of S. typhimurium. Additionally, quorum sensing-regulated behaviors of Pseudomonas aeruginosa, including swarming, swimming and twitching motility and alkaline protease production were investigated. Most effective drugs on swarming, swimming and twitching motility and alkaline protease production, respectively, were paroxetine and duloxetine; duloxetine; hydroxyzine and venlafaxine; paroxetine and venlafaxine; venlafaxine. Accordingly, psychotropic drugs were shown strongly anti-QS activity by acting as bacterial efflux pump inhibitors and effection on motility and alkaline protease production of P. aeruginosa.Publication Immobilization of bacillus subtilis e6-5 protease and commercial protease in nanofibrils containing different amino acids(Trakya Univ Balkan Yerlesesi Enstituler Binasi, 2020-04-01) Güler, Baran Enes; Demirkan, Elif; DEMİRKAN, ELİF; Sevgi, Tuba; SEVGİ, TUBA; Bursa Uludağ Üniversitesi/Fen Edebiyat Fakültesi/ Biyoloji Anabilim Dalı.; 0000-0001-7967-9041; 0000-0002-5292-9482; GWU-7780-2022; AAG-7112-2021; ABI-4472-2020In this study, polyamide 6 polymer surfaces that have a high surface area were produced by electrospinning method with the participation of Glycine, Tyrosine and Glutamic acid amino acids, and lyophilized Bacillus subtilis E6-5 protease and commercial protease enzymes were immobilized on nanofibrils. Enzyme reusability were investigated. The immobilization efficiencies of the enzymes were approximately between 50-55 %. In studies with lyophilized Bacillus protease, glutaraldehyde activated PA6 nanofibrils and glutaraldehyde unactivated PA6 nanofibrils were found to be more immobilized in the presence of Glutamic acid. Although the lyophilized protease enzyme immobilized on non-glutaraldehyde activated and activated surfaces has been used 4 times, the best functional stability has been achieved with 2 times use. In pure PA6/Glutamic acid nanofibrils, the immobilization yield of the two times used enzymes was found to be 38 %. In glutaraldehyde-activated PA6 nanofibrils, the PA6/Glutamic acid nanofibril surfaces were found to have 65 % immobilization yield of the two repetitive used enzymes. The enzyme immobilization efficiency has been doubled by glutaraldehyde activation of the nanofibrils. In studies with commercial protease, the most functional stability was obtained for 3 repeated uses, although the enzyme was used 6 times on the non-glutaraldehyde activated nanofibril surfaces. The most successful immobilization was found in 58 % of PA6 nanofibrils. In glutaraldehyde-activated PA6 nanofibrils, the enzyme was found to be used 6 times, but the functional stability was maintained as much as 4 times of repeated use.Publication Optimization of culture medium for the production and partial purification and characterization of an antibacterial activity from brevibacillus laterosporus strain EA62(Ars Docendi, 2019-07-01) Usta, Alev A. K.; Demirkan, Elif; Cengiz, Murat; Sevgi, Tuba; Zeren, Behice; Abdou, Maoulida; Usta, Alev A. K.; DEMİRKAN, ELİF; CENGİZ, MURAT; SEVGİ, TUBA; Zeren, Behice; Abdou, Maoulida; Bursa Uludağ Üniversitesi/Fen-Edebiyat Fakültesi/Biyoloji Bölümü.; Bursa Uludağ Üniversitesi/Veteriner Fakültesi/Farmakoloji ve Toksikoloji Anabilim Dalı.; 0000-0002-5292-9482; ABI-4472-2020; ABE-5935-2020; IPA-7484-2023; ISY-3462-2023; EID-6407-2022; CAU-1487-2022The present study was performed to report the bacterial identification, optimization of culture conditions and characterization of a novel antibiotic substance from a Bacillus sp. EA62 strain isolated from soil. The EA62 strain was identified based on 16S rRNA analysis. The new isolate EBD 9-1 showed 100% sequence identity with Brevibacillus laterosporus. The antibacterial activity of the new substance was examined against five pathogenic bacteria and was observed to be the most effective against Escherichia coli. An agar diffusion assay was performed to evaluate the antibacterial activity of the substance. The effects of some nutritional (amino acid, carbon, nitrogen and metal sources) and physical factors (pH and temperature) and incubation time on the antibiotic activity were studied. Antibiotic activity in basal medium reached the maximum levels after 72 h of incubation. The best antibiotic activity was obtained in the presence of glucose as a carbon source, yeast extract as a nitrogen source, glutamic acid as an amino acid source and MgSO4+CaCO3 as metal ion sources. For physical parameters, the best results were obtained at 37 degrees C, pH 7.0. The antibiotic substance was partially purified, and the estimated molecular weight was 6.3 kDa. The minimum inhibitory concentration (MIC) values determined against five pathogen bacteria were >256 mu g/ml. The substance was identified by thin-layer chromatography, and its Rf value was measured as 0.04 cm.Publication The effect of growth parameters on the antibiotic activity and sporulation in bacillus spp. isolated from soil(Slovak Univ Agriculture Nitra, 2013-04-01) Usta, Alev; Demirkan, Elif; Usta, Alev; DEMİRKAN, ELİF; Uludağ Üniversitesi; 0000-0002-5292-9482; ABI-4472-2020; GFJ-9415-2022Fifty-two Bacillus strains, which were isolated from different soil samples, were screened for antibiotic properties. The Bacillus strains were checked for antibacterial properties by the cross-streak method against 5 test pathogens, and 25 Bacillus strains had an effect on the test microorganisms. One strain of Bacillus, which exhibited the largest inhibition zone (25 mm) against Shigella sonnei, was named Bacillus sp. EA62. The antibacterial activity from Bacillus sp. EA62 was tested in six different culture media against Shigella sonnei using the agar well diffusion method. The best activity medium was selected and used for further studies. The influence of the incubation period, pH, and different glucose and nitrogen concentrations on the antibacterial activity was studied. The optimal conditions for the strongest antibiotic activity were found to be 72 hours (18 mm), pH 7.5 (23 mm), 3% glucose (25 mm), and 0.3% nitrogen concentration (23 mm). Additionally, the relationship between the antibiotic activity and sporulation was investigated. Accordingly, it was determined that the increase of the activity paralleled sporulation.