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The Metabolic Relationships between Probiotics and Fatty Acids

100%
Dayangaç A., Erdem B.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
816-818
EN
Probiotics are alive bacteria that have a healthy effect on the hosts and are found in large quantities in the soil and foods. The most recommended probiotics as commercial are the some species of Lactobacillus sp., Bifidobacterium sp., and Streptococcus sp. The fatty acids are formed by the colonic gut flora from dietary fibres, which manage to escape the host's enzymatic digestive systems in the small intestine. Dietary fibres that manage to reach the large intestine are available for several bacterial fermentative reactions. The fermentation of the different dietary fibres leads to an increase in concentrations of several short-chain fatty acids, especially butyrate, propionate and acetate, in the lumen of the proximal regions of the large intestine. In this review, we acquainted that the relationship between fatty acids and probiotic bacteria affects some various health ailments.
2
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The Presence of Metals and Antibiotics Resistant Bacteria in Arable Manure Soils

81%
Erdem B., Dayangaç A., Şahin İ.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
570-571
EN
Heavy metals and antibiotics resistance are intense public interest owing to their pollution in the environment and potential deleterious effects on human health. A total of 15 isolates of Bacillus subtilis, Bacillus cereus, Pseudomonas aeruginosa and Escherichia coli (50 manure garden soils) were tested for their resistance against certain heavy metals and antibiotics. Minimum inhibitory concentrations of Pb²⁺, Co²⁺, Cu²⁺, and Zn²⁺ for each isolate were also determined. B. subtilis, B. cereus, P. aeruginosa and E. coli exhibited high tolerance to minimum inhibitory concentrations of 3,200 μg/ml for Pb²⁺, 400 μg/ml for Cu²⁺ and Co²⁺, and 100 μg/ml for Zn²⁺ in agar plates. All the isolates were highly resistant to lead and they showed 100% growth in 3,200 μg/ml concentration. It was observed that all isolates were resistant to a wide range of antibiotics namely clindamycin, ceftazidime, aztreonam and vancomycin.
3
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Direct and Postsynthetic Functionalization of Mesoporous B-SBA-15-SO₃H Acid Catalyst and Application to Methyl Propionate Esterification

81%
Erdem B., Azko Ç., Erdem S., Öksüzoğlu R.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
756-759
EN
Organic functionality can be added to mesoporous silicates in two ways: either by covalent grafting (postsynthetic) of various functional groups onto the channel walls or by incorporating functionalities directly during the synthesis (one-pot). If the grafted catalytically active groups experience similar environments and are isolated from each other, catalysis process is greatly facilitated. For this purpose, boric acid, as boron source, was added into the initial reaction mixture and then acid functionalization was performed by post and direct method. The obtained acid catalysts were tested in the esterification of propionic acid with methanol and the activity of these new materials was compared to that of SBA-15-SO₃H. Boron addition has facilitated the methyl propionate esterification for both postsynthetic and direct functionalized acid catalyst. Boron incorporated and postsynthetic functionalized mesoporous acid catalyst has highly enhanced the esterification reaction, compared to direct functionalized acid catalyst. The post functionalization method seems to be superior to one-pot functionalization method for preparation of mesoporous acid catalysts.
4
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Magnetic Mesoporous Silica Nanocomposite for Biodiesel Production

81%
Erdem S., Öksüzoğlu R., Avşar S., Erdem B.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
763-766
EN
Ordered mesoporous silicas can be utilized as support because of having large surface area, tunable porosity, uniform pore size distribution, high thermal stability and modifiable properties. However, these materials introduce separation problems in liquid-phase processes. We have prepared Fe₃O₄-SBA-15-SO₃H solid acid catalyst by combining the properties of a magnetic material and the mesoporous character of silica. The sulfonic acid functionalized solid acid catalyst, containing both magnetic nanoparticles and mesoporous silica, is not only separable but also stable under hydrothermal conditions, which are usually employed for biodiesel production. Esterification of oleic acid with methanol for biodiesel production was carried out effectively and 75% conversion of ester was approximately reached within six hours in the presence of Fe₃O₄-SBA-15-SO₃H magnetic solid acid catalyst. In addition, the catalyst could be separated from the reaction system by applying external magnetic field and reused without deactivation.
5
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Effect of Heavy Metals and Antibiotics on Siderophores Producing Bacterial Isolates

71%
Erdem B., Dayangaç A., Günaydin M., Tulumoğlu Ş., Yilmaz M.
Acta Physica Polonica A
|
2016
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vol. 130
|
issue 1
181-183
EN
In this study, siderophore-producing bacterial species have been isolated from soils contaminated with diesel oil. In P. aeruginosa (P-7) production of siderophores was inhibited at concentrations of ZnSO₄ and CoCl₂ of 2000 μM, while B. subtilis (BS-1) has increased siderophores production at similar concentrations of CoCl₂ and ZnSO₄. The same bacteria have increased the production of siderophores in presence of streptomycine (512 mg/ml). In B. subtilis the production of siderophores was inhibited by cefuroxime. The results show the effect of metals on the efficiency of siderophore production by bacteria for potential application in bioremediation of metal-contaminated iron-deficient soils in the microbial assisted phytoremediation processes. The results include the effect of metals on siderophore production efficiency of the bacteria used for the bioremediation of metal-contaminated soils. In conclusion, it has been found that heavy metals and antibiotics significantly effect the production of siderophores by bacteria.
6
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Preparation, Characterization and Catalytic Properties of SBA-15-SO₃H Supported Tungstophosphoric Acid for Esterification Reaction

71%
Erdem B., Erdem S., Çıtak A., Yavru C., Öksüzoğlu R.
Acta Physica Polonica A
|
2017
|
vol. 132
|
issue 3
1041-1044
EN
SBA-15-SO₃H supported tungstophosphoric acid (TPA, H₃PW₁₂O₄₀) mesoporous materials were synthesized by impregnation of TPA into the hydrothermally synthesized SBA-15-SO₃H and the catalytic performances were compared for the esterification reaction. The physical and chemical properties of the catalysts were characterized by XRD, SEM/EDX, FT-IR and N₂ adsorption/desorption techniques. The characterization results show that TPA/SBA-15-SO₃H retained the typical mesoporous structure of SBA-15-SO₃H. The experimental results indicated that TPA/SBA-15-SO₃H is a more efficient catalyst than SBA-15-SO₃H for the esterification reaction. The higher activity of TPA/SBA-15-SO₃H compared with that of SBA-15-SO₃H was consistent with the material having the low pKa value, confirming that the esterification rate was mostly dependent on the acid strength of the additional functional groups of solid acid catalyst. Accordingly, the reason for the catalytic activity difference was simply explicated by the effect of TPA, having low pKa value, affecting the pore structure and the total acidity.
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