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A Novel Raw Starch Hydrolyzing Thermostable ?-Amylase Produced by Newly Isolated Bacillus mojavensis SO-10: Purification, Characterization and Usage in Starch Industries
(Inst Tecnologia Parana, 2018) Ozdemir, Sadin; Fincan, Sema Aguloglu; Karakaya, Adem; Enez, Baris
The aim of this study is the production, purification, and characterisation of thermostable raw starch hydrolyzing aamylase produced by Bacillus mojavensis SO-10. The maximum production conditions of alpha-amylase were found at 36th hour, 35 degrees C and pH 7.0. We utilized three steps to purify the thermostable alpha-amylase and as a result, 34-fold and 18% yield were obtained. The molecular weight of purified alpha-amylase was determined as 73 kD. The K-m and V-max, rates were detected as 0.010 mM and 3.38 ,umol min(-1), respectively. This purified alpha-amylase exhibited the highest activity at pH 5.0-6.0 and 70 degrees C and showed stability over a wide variety of pH and temperature at 4.0-8.0, and 4050 degrees C, respectively. The thermostable purified alpha-amylase exhibited stability in the presence of denaturing agents and heavy metal ions. The purified enzyme hydrolyzed the raw starches of corn and wheat grains in the ratio of 36.7% and 39.2% respectively. The end-yields of soluble starch hydrolysis were analyzed by thin-layer chromatography (TLC). In addition, the usage of purified a-amylase in clarification of apple juice and domestic washing detergent industries were evaluated.
Anoxybacillus sp. SO B1-Immobilized Amberlite XAD-16 for Solid-Phase Preconcentration of Cu(II) and Pb(II) and Their Determinations by Flame Atomic Absorption Spectrometry
(Taylor & Francis Inc, 2015) Oral, Elif Varhan; Ozdemir, Sadin; Dolak, Ibrahim; Okumus, Veysi; Dundar, Abdurrahman; Ziyadanogullari, Berrin; Aksoy, Zehra
A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1-immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0ml of 1.0mol L-1 HCI and 10.0ml of 0.25mol L-1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 +/- 1.57% and 100.3 +/- 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3s, N = 10) were found to be 0.8 and 1.6 mu g L-1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbakir and Elazig, Lake of Hazar in Elazig, and tap water in Diyarbakir. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).
Antioxidant Properties of Cultured Mycelia from Four Pleurotus Species Produced in Submerged Medium
(Taylor & Francis Inc, 2013) Dundar, Abdurrahman; Okumus, Veysi; Ozdemir, Sadin; Yildiz, Abdunnasir
The ethanolic extracts of dried cultured mycelia of Pleurotus ostreatus, Pleurotus eryngii, Pleurotus florida, and Pleurotus sajor-caju were analyzed for antioxidant activity in different systems. Tests used are as follows: reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, metal chelating activitiy, etc.; total phenolic content was determined. The percentage inhibition of P. ostreatus, P. eryngii, P. florida, and P. sajor-caju at 20 mg/mL concentration on peroxidation in a -carotenelinoleic acid system was 57.19, 60.68, 62.12, and 58.81%, respectively. The reducing power of P. eryngii was higher than the other samples, and its value was 0.86 at 10 mg/mL concentration. P. ostreatus and P. sajor-caju proved to be better at scavenging superoxide anion radicals than the P. eryngii and P. florida. In the scavenging effect of DPPH radical test, P. ostreatus showed the highest activity potential and P. sajor-caju showed the strongest metal chelating capacity.
Antioxidant, antimicrobial, cytotoxic and protective effects of truffles
(Academic Press Inc Elsevier Science, 2022) Fidan, Mehmet; Ali, Muhammad Muddassir; Erez, Mehmet Emre; Cigerci, Ibrahim Hakki; Ozdemir, Sadin; Sen, Fatih
Fungi can be used as a potent chemotherapeutic agent to treat various cancers. In current study acetone and methanol extracts of Terfezia claveryi, Terfezia boudieri, Terfezia olbiensis, Picoa lefebvrei, Picoa juniperi were used to assess total phenolic contents, antioxidant activity, ion-chelating impact, antimicrobial activity, the cytotoxic and protective effects. Both methanol and acetone extracts of T. boudieri had the highest FRAP and DPPH scavenging abilities. Dose-dependent increased ion-chelating impact of all tested truffles species was found. Extracts of T. boudieri, T. claveryi, and T. albiensis exhibited higher antimicrobial activities. T. claveryi and T. boudieri showed the highest protective effects against H2O2-induced genotoxicity (P < 0.05), in S. cerevisiae BY4741. The least protective effect was showed by the acetone extracts of T. olbiensis (144 +/- 8); methanol ex-tracts of P. lefebvrei (140 +/- 8) and P. juniperi (140 +/- 10). MCF 7 cells showed more sensitivity against to methanol extracts of T. boudieri at 10-100 mu g/mL concentrations. HepG2 cells showed more sensitivity against the methanolic extracts of T. boudieri at both doses. Overall, P. lefebvrei and P. juniperi extracts had the least cytotoxic effects. The species of Terfezia exhibit significant protective effects against DNA damage and also have the potential of cytotoxicity effects.
Application of magnetized fungal solid phase extractor with Fe2O3 nanoparticle for determination and preconcentration of Co(II) and Hg(II) from natural water samples
(Elsevier Science Bv, 2018) Ozdemir, Sadin; Mohamedsaid, Siham Abdullah; Kilinc, Ersin; Yildirim, Aydil; Soylak, Mustafa
Pleurolus eryngii loaded Fe2O3 magnetic nanoparticles were developed as novel magnetic solid phase bio-extractors for the preconcentrations and extractions of Co(II) and Hg(II) from real samples. The metal binding surface groups of the prepared magnetic solid phase bio-extractors were investigated by FT-IR spectrometry, SEM and EDX. Several parameters influencing the magnetic extractions and preconcentrations of Co(II) and Hg (II) were examined and optimized, including pH, flow rate, quantity of P. eryngii, quantity of Fe2O3 magnetic nanoparticle, eluent type, concentration and volume, sample volume, and foreign ions. A good reusage (35 times) was obtained with the relative standard deviation (RSD) of < 5.0% for both magnetic solid phase bio-extractors. The biosorption capacities were determined for Co(II) and Hg(II) as 25.4 mg g(-1) and 30.3 mg g(-1), respectively, using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The preconcentration factors for Co(II) and Hg(II) were found as 80 and 100, respectively, when using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The developed procedures were validated through analysis of the certified reference materials and successfully utilized for the determinations of Co(II) and Hg(II) in real samples by inductively coupled plasma optical emission spectrometry (ICP-OES) with satisfactory results.
Bacillus sp immobilized on Amberlite XAD-4 resin as a biosorbent for solid phase extraction of thorium prior to UV-vis spectrometry determination
(Springer Wien, 2010) Ozdemir, Sadin; Erdogan, Sait; Kilinc, Ersin
A method has been developed for the preconcentration of Th prior to its determination by UV-vis spectrophotometry after complexation with Arsenazo Ill. A column was packed with Amber lite XAD-4 resin containing immobilized Bacillus sp. as a solid phase extractant. Parameters such as pH of the solution and sample, the concentration of Th, the volume and type of eluent, flow rate and effect of matrix interference were studied. The optimum pH for the sorption of Th is 5.0, and quantitative eluation occurs with 1 mol L-1 HCl. The tolerance limits of some electrolytes were also studied. The loading capacity was determined to be 17.2 mg g(-1) The method was applied to the determination of Th in real ore sample and validated by analyzing a certified reference samples (NCS DC-73350; poplar leaves).
Bioaccumulation, Resistance, Removal of U(VI) and Th(IV) and Their Effects on Antioxidant Enzymes on Thermophilic Anoxybacillus flavithermus ST15
(Taylor & Francis Inc, 2022) Acer, Omer; Kilinc, Ersin; Ozdemir, Sadin
In this research, a novel heavy metals resistance thermophilic Anoxybacillus flavithermus ST15 was isolated from a hot spring mud sample in Afyonkarahisar (Omer). 16S rRNA analyzing revealed that strain ST15 was 99.7% similar to Anoxybacillus flavithermus subsp. yunnanensis str. E13. We propose that U(VI) and Th(IV) have an effect on A. flavithermus at the cellular level and that this bacteria can be used as a bioindicator. Therefore, the effects of U(VI) and Th(IV) resistance, removal, and bioaccumulation on the antioxidant enzyme systems of thermophilic A. flavithermus have been thoroughly investigated. SOD and CAT activities were observed to be increased by different concentrations of U(VI) and Th(IV). A scanning electron microscope and fourier transform infrared spectroscopy were used to analyze changes in the surface macrostructure and functionality of A. flavithermus following interaction with U(VI) and Th(IV). The highest bioaccumulation efficiency amounts for U(VI) were 102.36 mg/g dried bacteria at 24 h at 12.5 mg/l concentration and 105.7 mg/g dried bacteria at 36 h at 12.5 mg/l concentration was detected for Th(IV). At the 24th h and 12.5 mg/l, the highest U(VI) and Th(IV) cell membrane bioaccumulation capacities of A. flavithermus were calculated as 307.08 and 289.52 mg metal/g wet membrane, respectively. This is the first research to examine U(VI) and Th(IV) resistance, removal, and bioaccumulation in thermophilic A. flavithermus.
Bioaccumulation, tolerance, and removal of U(VI) and Th(IV) by a novel thermophilic Bacillus cereus ST14 isolated from hot spring mud samples in Afyonkarahisar, Turkey
(Springer Heidelberg, 2024) Ozdemir, Sadin; Acer, Omer; Kilinc, Ersin
In this study, a novel thermophilic Bacillus cereus ST14 with heavy metal tolerance was isolated from a hot spring mud sample in Afyonkarahisar (Omer). 16S rRNA analysis revealed that strain ST14 was mostly related to Bacillus cereus strain 151,007-R3_K09_40_27F (98.18%) and Bacillus cereus strain 2 k (98.10%). We hypothesized that U(VI) and Th(IV) affected B. cereus at the cell level and that this bacterium can be used as a bioindicator. Therefore, U(VI) and Th(IV) tolerance, removal, bioaccumulation, and impacts on antioxidant enzymes of thermophilic B. cereus have been examined in detail. Changes in the surface macrostructure and functionality of B. cereus following interaction with U(VI) and Th(IV) were studied using a scanning electron microscope and fourier transform infrared spectroscopy. B. cereus was found to be highly resistant to 10 and 12.5 mg/L of U(VI) and Th(IV) after 24-h incubation. Superoxide dismutase (SOD) and catalase (CAT) activities were observed to be increased by different U(VI) and Th(IV) concentrations. The highest bioaccumulation capacity quantities were detected as 100.79 and 87.96 mg metal/g dried bacteria at 24th h at 12.5 mg/L concentration for U(VI) and Th(IV), respectively. The highest U(VI) and Th(IV) cell membrane bioaccumulation capabilities of B. cereus have been measured as 318.94 and 263.89 mg metal/g wet membrane, respectively, at 24 h and 12.5 mg/L. This study's findings suggested that B. cereus could be employed as a bioindicator organism for detecting metal contamination in natural or industrial water samples. However, further research should focus on other thermophilic microorganisms.
Biosorption of 2,4-d, 2,4-DP, and 2,4-DB from aqueous solution by using thermophilic anoxybacillus flavithermus and analysis by high-performance thin layer chromatography: Equilibrium and kinetic studies
(Wiley, 2012) Ozdemir, Sadin; Bekler, Fatma Matpan; Okumus, Veysi; Dundar, Abdurrahman; Kilinc, Ersin
In this study, the potential biosorption characteristics of the thermophilic Anoxybacillus flavithermus (A. flavithermus) was investigated for the removal of the chlorophenoxy acid derivates, namely, 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP or dichlorprop), and 2,4-dichlorophenoxy butyric acid (2,4-DB). The experiments were performed for the simultaneous biosorption of the studied pesticides. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticides concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously analyzed by high performance thin layer chromatography. The optimum parameters were found as pH: 4.0 for biosorption medium, 60 min of contact time, 50 mg of bacteria, and 50 mg L-1 of initial pesticides concentrations. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by A. flavithermus as biomass. Biosorption of pesticides on to A. flavithermus showed pseudo first-order rate kinetics at different initial concentration of pesticides and different temperatures. The experimental adsorption data were fitted both the Langmuir and Freundlich adsorption models. Fourier-transform Infrared spectroscopy was used to understand the bonding mechanism of pesticides to biosorbent and surface functionality of the biosorbent The highest pesticide uptake was calculated from Langmuir isotherm and found to be 24.15 mg g-1 for 2,4-D. Among the studied pesticides, 2,4-DP showed difference adsorption behavior. According to in your comments the reason of this that 2,4-DP contain an asymmetric carbon atom, which provide a molecular chirality. (C) 2011 American Institute of Chemical Engineers Environ Prog, 2011
Biosorption of chlorophenoxy acid herbicides from aqueous solution by using low-cost agricultural wastes
(Taylor & Francis Inc, 2015) Okumus, Veysi; Celik, K. Serdar; Ozdemir, Sadin; Dundar, Abdurrahman; Kilinc, Ersin
The potential biosorption abilities of apple shell (AS), orange peel (OP), banana peel (BP), and millet waste (MW) as a bio-waste material to remove 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP), and 2,4-dichlorophenoxy butyric acid (2,4-DB) from aqueous solution were investigated in batch condition. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticide concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously determined by high performance thin layer chromatography. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by agricultural wastes. The experimental adsorption data were fitted to Langmuir adsorption models (r(2)>0.99). It was found that adsorption of 2,4-DP was higher for all biosorbent. The highest maximum adsorption capacities of 2,4-DP were found as 40.08, 22.71, 33.26, and 45.45mg/g, respectively, for AS, OP, BP, and MW. Maximum adsorption capacity was obtained for 2,4-D as OP>MW>BP>AS, 2,4-DP as MW>AS>BP>OP, and 2,4-DB as OP>AS>BP>MW. From the results, it can be said that MW was an effective biosorbent for removal of 2,4-DP and OP was an effective biosorbent for removal of 2,4-D and 2,4-DB through the studied pesticides. Optimum biosorption conditions were determined as 60min of contact time, 100mg of biomass, AS at pH 6.0, OP at pH 6.0, MW at pH 7.0, and BP at pH 7.0. FT-IR was employed to understand the surface properties of biosorbents. According to the results, agricultural wastes have high adsorption capacity.
Biosorption of Heavy Metals (Cd2+, Cu2+, Co2+, and Mn2+) by Thermophilic Bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus: Equilibrium and Kinetic Studies
(Taylor & Francis Inc, 2013) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara
Two strains of thermophilic bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus, were employed to investigate the biosorption of heavy metals including Cd2+, Cu2+, Co2+, and Mn2+ ions. The effects of different biosorption parameters such as pH (2.010.0), initial metal concentrations (10.0300.0mg L-1), amount of biomass (0.2510g L-1), temperature (3080 degrees C), and contact time (15120min) were investigated. Concentrations of metal ions were determined by using an inductively coupled plasma optical emission spectrometry (ICP-OES). Optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption by Geobacillus thermantarcticus were found to be 4.0, 4.0, 5.0, and 6.0, respectively. For Anoxybacillus amylolyticus, the optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption were found to be 5.0, 4.0, 5.0, and 6.0, respectively. The Cd2+, Cu2+, Co2+, and Mn2+ removals at 50mg L-1 in 60min by 50mg dried cells of Geobacillus thermantarcticus were 85.4%, 46.3%, 43.6%, and 65.1%, respectively, whereas 74.1%, 39.8%, 35.1%, and 36.6%, respectively, for Anoxybacillus amylolyticus. The optimum temperatures for heavy metal biosorption were near the optimum growth temperatures for both strains. Scatchard plot analysis was employed to obtain more compact information about the interaction between metal ions and biosorbents. The plot results were further studied to determine if they fit Langmuir and Freundlich models.
Comparative solid phase extraction study on the U(VI) preconcentration by using immobilized thermotolerant Bacillus vallismortis and Bacillus mojavensis
(Springer, 2018) Ozdemir, Sadin; Oduncu, M. Kadir; Kilinc, Ersin; Soylak, Mustafa
Bacillus vallismortis and Bacillus mojavensis were loaded onto Amberlite XAD-4 resin and used for solid phase extraction (SPE) of uranium(VI). A quick and simple UV-Vis spectrophotometric method was used to determine U(VI) ion. The best experimental conditions were determined as being a pH of 5.0; a sample flow rate of 2.0 mL min(-1); 200.0 mg of biosorbent; 800 mg of Amberlite XAD-4, and 5.0 mL of 1 mol L-1 HCl as desorption solution for both immobilized bacteria. The preconcentration factors were achieved as 80 for both solid phase extractor. The developed methods were validated by applying to reference water and tea samples.
Determination of cytotoxic, anticholinesterase, antioxidant and antimicrobial activities of some wild mushroom species
(Informa Healthcare, 2016) Dundar, Abdurrahman; Okumus, Veysi; Ozdemir, Sadin; Celik, Kadir Serdar; Boğa, Mehmet; Ozcagli, Eren
In the performed study of methanol extraction of wild edible mushroom species; Agaricus arvensis, Agaricus campestris, Armillaria mellea, Fomes fomentarius, Coprinus micaceus, Coriolus versicolor and Lactarius deliciosus were examined for screening their cytotoxic, anticholinesterase, antioxidant and antimicrobial capacity. Phenolic acid composition of mushrooms was also analysed. L. deliciosus and F. fomentarius were generally showed the highest activities at antioxidant test systems (metal chelating, superoxide anion radical scavenging, total antioxidant, 2,2-diphenyl-1-picrylhydrazyl radical scavenging and reducing power activity tests). The highest activities at antimicrobial activity displayed by A. arvensis and as 18 ± 0.8 against to Staphylococcus aureus. The best IC50 values of mushroom methanol extracts at anticancer activities on HeLa and NRK-52E were 7.09 and 18.23 mg/mL exhibited by C. micaceus and A. campestris, respectively. The highest butyrylcholinesterase activity exhibited by L. deliciosus. Total amount of phenolic acids were found as 1,224.70 mg/kg at L. deliciosus. © 2016 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license.
DNA cleavage properties and synthesis of metallophthalocyanines with 5-methyl-[1,2,4] triazolo [1, 5-a] pyrimidin-7-oxy substituents
(Taylor & Francis Inc, 2017) Agirtas, M. Salih; Ondes, M. Yusuf; Ozdemir, Sadin; Okumus, Veysi
The aim of the present study is to perform synthesis of novel metallophthalocyanines (pcs) with high solubility. The synthesis and characterization of 5-methyl-[1, 2, 4] triazolo [1, 5-a] pyrimidin-7-yloxy-substituted zinc, magnesium, and cobalt pcs are reported. These compounds have been characterized using electronic absorption, nuclear magnetic resonance spectroscopy, infrared, elemental analysis and mass spectra. The aggregation investigations carried out in different concentrations indicate that 5-methyl-[1, 2, 4] triazolo [1, 5-a] pyrimidin-7-yloxy-substituted pc complexes do not have any aggregation behavior for the concentration range of 1 x 10(-5) -1 x 10(-6) M in THF. DPPH radical scavenging activity, metal chelating activity, and reducing power of the compounds were evaluated. The DNA gel electrophoresis studies revealed that new phthalonitrile and its metallophthalocyanine compounds cleavaged plasmid DNA (pBR322). Additionally, the ground-state geometries of the complexes were optimized using density functional theory methods at B3LYP/6-31G (d, p) level in order to obtain information about the 3D geometries and electronic structure.
Geobacillus thermoleovorans immobilized on Amberlite XAD-4 resin as a biosorbent for solid phase extraction of uranium (VI) prior to its spectrophotometric determination
(Springer Wien, 2012) Ozdemir, Sadin; Kilinc, Ersin
Geobacillus thermoleovorans subsp stromboliensis, was immobilized on an Amberlite XAD-4 ion exchanger and used as a solid phase extractant for the preconcentration of U(VI) ions prior to their determination by UV-VIS spectrophotometry. Parameters affecting the preconcentration (such as the pH value of the sample solution, the concentration of U(VI), the volume and type of eluent, the flow rate and the effect of potentially interfering ions) were studied. The optimum pH for the sorption of U(VI) was found to be pH 5.0. 5.0 mL of 1 M hydrochloric acid were used to eluate the U(VI) from the column. The loading capacity is 11 mg g(-1). The limits of detection and quantification are 2.7 and 9.0 mu g L-1, respectively, and relative standard deviations are < 10 %. The method was applied to the determination of U(VI) in a certified reference sample (NCS ZC-73014; tea leaves) and in natural water samples.
Investigation of two different size microplastic degradation ability of thermophilic bacteria using polyethylene polymers
(Taylor & Francis Ltd, 2023) Akarsu, Ceyhun; Ozdemir, Sadin; Ozay, Yasin; Acer, Omer; Dizge, Nadir
There are several studies stating that many types of microplastics cannot be retained completely by conventional wastewater treatment systems. Therefore, it is necessary to prevent the discharge of these microplastics to the ecological system. The objective of this study was to investigate the biodegradation ability of two different size of PE (50 and 150 mu m) by using two Gram-positive, spore-forming, rod-shaped, and motile thermophilic bacteria, called strain Gecek4 and strain ST5, which can hydrolyse starch, were isolated from the soil's samples of Gecek and omer hot-springs in Afyonkarahisar, Turkey, respectively. Phenotypic features and 16S rRNA analyzing of strains also studied. According to these results, Gecek4s and ST5 were identified as Anoxybacillus flavithermus Gecek4s and Bacillus firmus ST5, respectively. Results showed that A. flavithermus Gecek4s could colonise the polymer surface and cause surface damage whereas B. firmus ST5 could not degrade bigger-sized particles efficiently. In addition, morphological changes on microplastic surface were investigated by scanning electron microscopy (SEM) where dimensional changes, irregularities, crack, and/or holes were detected. This finding suggests that there is a high potential to develop an effective integrated method for plastic bags degradation by extracellular enzymes from bacteria.
Investigations of Hg(II) and Pb(II) tolerance, removal and bioaccumulation and their effects on antioxidant enzymes on thermophilic Exiguobacterium profundum
(Taylor & Francis Inc, 2020) Akkoyun, Mahire Bayramoglu; Ozdemir, Sadin; Kilinc, Ersin; Birhanli, Emre
Hg(II) and Pb(II) tolerance, removal, bioaccumulation and effects on antioxidant enzymes of thermophilic Exiguobacterium profundum were investigated. The results indicated that Hg(II) was more toxic than Pb(II) to E. profundum. E. profundum was also more tolerant in solid medium than in liquid medium for Pb(II) and Hg(II). The bacterial growth was not significantly influenced at 1.0 and 2.5 mg/L Pb(II) and Hg(II) for 24 h. The highest Hg(II) and Pb(II) bioaccumulation amounts were determined as 37.56 and 54.35 mg metal/dried bacteria, respectively. Bioaccumulation capacities of the cell membrane of E. profundum for Hg(II) and Pb(II) were determined. The different concentrations of Pb(II) and Hg(II) enhanced the SOD and CAT enzymes. In addition, variations of the surface macrostructure and the functionality of E. profundum after the interaction with Hg(II) and Pb(II) were investigated by the scanning electron microscope (SEM) and the Fourier transform infrared spectroscopy (FT-IR), respectively. This investigation obviously showed that thermophilic E. profundum can also be applied for removal and recovery of toxic metals from industrial wastewater. Clearly, a further investigation should be utilized by thermophilic microorganisms. According to antioxidant enyzme activities, E. profundum can be also used as a bioindicator for the detection of toxic metal pollution in natural water samples.
Isolation of a thermophilic Anoxybacillus flavithermus sp nov and production of thermostable ?-amylase under solid-state fermentation (SSF)
(Bmc, 2012) Ozdemir, Sadin; Matpan, Fatma; Okumus, Veysi; Dundar, Abdurrahman; Ulutas, Mehmet Sefa; Kumru, Mert
A new bacteria was isolated from hot-spring water of Gazligol, Afyonkarahisar in Turkey. Based on morphological and biochemical tests and 16S rRNA gene sequence analysis, the isolate belonged to the Anoxybacillus flavithermus species which has 99% similarity with the bacterium DNA. The production of alpha-amylase by thermophilic Anoxybacillus flavithermus was investigated under solid-state fermentation by using some agricultural waste as substrates. Solid substrates such as rice husk, banana husk, millet, water melon husk, lentil bran, wheat bran and maize oil cake were studied for enzyme production. Of these, rice husk was proved as the best substrate for alpha-amylase production (1,271 U/mg). The maximum alpha-amylase production was observed as 1,803 U/mg at 72 h, 1,000 mu m particle size, 70% initial moisture content (w/v), and 40% inoculum level (v/w). Among the various nitrogen sources tested, 1% peptone (3,170 U/mg) was found to be the best nitrogen source for alpha-amylase production. As additional carbon sources, 1% starch (2,364 U/mg) enhanced alpha-amylase production. The optimum temperature for the activity of alpha-amylase was found to be 70A degrees C. The enzyme was optimally active at pH 6.0 and stable in the pH range of 6.0-8.0.
Isolation of Thermophilic Bacteria and Investigation of Their Microplastic Degradation Ability Using Polyethylene Polymers
(Mdpi, 2022) Ozdemir, Sadin; Akarsu, Ceyhun; Acer, Omer; Fouillaud, Mireille; Dufosse, Laurent; Dizge, Nadir
Microplastics (MPs) pose potential public health challenges because of their widespread occurrences in all environmental compartments. While most studies have focused on the occurrence fate of microplastics in wastewater treatment systems, the biodegradation of microplastics in wastewater is generally little understood. Therefore, we used two Gram-positive and thermophilic bacteria, called strain ST3 and ST6, which were identified by morphological, biochemical, physiological, and molecular analyses, to assess the growth and biodegradation potential of two different sized (50 and 150 m) polyethylene particles. The degradation was monitored based on structural and surface morphological changes. According to 16S rRNA analyses, ST3 and ST6 were identified as Anoxybacillus flavithermus ST3 and Anoxybacillus sp. ST6, respectively. The occurrence of cracks, holes, and dimensional changes was detected by scanning electron microscopy. Moreover, critical characteristic absorption band formation and modifications were determined by Fourier transform infrared spectroscopy. In addition to these, it was found that Anoxybacillus flavithermus ST3 and Anoxybacillus sp. ST6 produced high level of alpha-Amylase. These results showed that thermophilic bacteria are capable of the biodegradation of microplastics and production of alpha-Amylase.
Magnetic solid phase extractions of Co(II) and Hg(II) by using magnetized C-micaceus from water and food samples
(Elsevier Sci Ltd, 2019) Ozdemir, Sadin; Mohamedsaid, Siham Abdullah; Kilinc, Ersin; Soylak, Mustafa
A new bio-MSPE sorbent based on the use of C. micaceus and gamma-Fe2O3 magnetic nanoparticle was prepared for the preconcentrations of Co(II) and Hg(II). Critical parameters including pH, flow rate, quantity of C. micaceus, quantity of gamma-Fe2O3 magnetic nanoparticle, eluent (type, concentration and volume), sample volume, and foreign ions were examined. Surface structure and variations after interaction with Co(II) and Hg(II) of bio-MSPE sorbent were investigated by FT-IR, SEM, and EDX. The impact of bio-MSPE column reusage was also tested. The biosorption capacities were determined as 24.7 mg g(-1) and 26.2 mg g(-1), respectively for Co(II) and Hg(II). Certified reference materials were utilized to find out the accuracy of the prepared bio-MSPE method. This novel bio-MSPE method was accomplished by being applied to real food and water samples. In particular, it will be possible to make use of C. micaceus as new alternatives, in environmental biotechnology applications.

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