TY  - JOUR
AU  - Pantić, Nevena
AU  - Prodanović, Radivoje
AU  - Ilic-Durdic, Karla
AU  - Polović, Natalija
AU  - Spasojević, Milica
AU  - Prodanović, Olivera
PY  - 2021
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1476
AB  - Removal of phenolic compounds from water is of major interest over the years, since they are one of the most common pollutants in aqueous systems. Horseradish peroxidase (HRP) is the most investigated biocatalyst for this purpose. Inactivation of the enzyme is a major issue which can be successfully overcome by the enzyme immobilization on different polymers. In this study, tyramine-alginate micro-beads were used as carriers for the immobilization of horseradish peroxidase. The effect of the oxidation degree of tyramine-alginates on a specific activity of the enzyme was tested. An increase in the concentration of oxidized alginate from 2.5 to 20% resulted in a gradual increase in the specific activity from 0.05 to 0.67 U/mL. HRP immobilized within these microbeads was tested for the phenol removal in a batch reactor. Reaction conditions were optimized to achieve a high removal efficiency and substantial reusability of the system. In this study, for the first time, an internal generation of hydrogen peroxide from glucose and glucose oxidase was employed in the phenol removal process with HRP immobilized on tyramine-alginate. Within 6 h of repeated use 96% of phenol was removed when the system for internal delivery of H2O2, composed of 0.187 U/mL of glucose oxidase and 4 mmol/L of glucose was employed. A common straightforward addition of hydrogen peroxide provided the removal efficiency of only 42%, under the same reaction conditions. The highest efficiency of the phenol removal (96%) was obtained with HRP immobilized within 20 mol% oxidized tyramine-alginate microbeads. Fifteen mol% oxidized tyramine-alginate showed lower removal efficiency in the first cycle of use (73%) but more promising reusability, since the immobilized enzyme retained 61% of its initial activity even after four consecutive cycles of use.
PB  - Elsevier, Amsterdam
T2  - Environmental Technology & Innovation
T1  - Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads
VL  - 21
DO  - 10.1016/j.eti.2020.101211
ER  - 

@article{
author = "Pantić, Nevena and Prodanović, Radivoje and Ilic-Durdic, Karla and Polović, Natalija and Spasojević, Milica and Prodanović, Olivera",
year = "2021",
abstract = "Removal of phenolic compounds from water is of major interest over the years, since they are one of the most common pollutants in aqueous systems. Horseradish peroxidase (HRP) is the most investigated biocatalyst for this purpose. Inactivation of the enzyme is a major issue which can be successfully overcome by the enzyme immobilization on different polymers. In this study, tyramine-alginate micro-beads were used as carriers for the immobilization of horseradish peroxidase. The effect of the oxidation degree of tyramine-alginates on a specific activity of the enzyme was tested. An increase in the concentration of oxidized alginate from 2.5 to 20% resulted in a gradual increase in the specific activity from 0.05 to 0.67 U/mL. HRP immobilized within these microbeads was tested for the phenol removal in a batch reactor. Reaction conditions were optimized to achieve a high removal efficiency and substantial reusability of the system. In this study, for the first time, an internal generation of hydrogen peroxide from glucose and glucose oxidase was employed in the phenol removal process with HRP immobilized on tyramine-alginate. Within 6 h of repeated use 96% of phenol was removed when the system for internal delivery of H2O2, composed of 0.187 U/mL of glucose oxidase and 4 mmol/L of glucose was employed. A common straightforward addition of hydrogen peroxide provided the removal efficiency of only 42%, under the same reaction conditions. The highest efficiency of the phenol removal (96%) was obtained with HRP immobilized within 20 mol% oxidized tyramine-alginate microbeads. Fifteen mol% oxidized tyramine-alginate showed lower removal efficiency in the first cycle of use (73%) but more promising reusability, since the immobilized enzyme retained 61% of its initial activity even after four consecutive cycles of use.",
publisher = "Elsevier, Amsterdam",
journal = "Environmental Technology & Innovation",
title = "Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads",
volume = "21",
doi = "10.1016/j.eti.2020.101211"
}

Pantić, N., Prodanović, R., Ilic-Durdic, K., Polović, N., Spasojević, M.,& Prodanović, O.. (2021). Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads. in Environmental Technology & Innovation
Elsevier, Amsterdam., 21.
https://doi.org/10.1016/j.eti.2020.101211

Pantić N, Prodanović R, Ilic-Durdic K, Polović N, Spasojević M, Prodanović O. Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads. in Environmental Technology & Innovation. 2021;21.
doi:10.1016/j.eti.2020.101211 .

Pantić, Nevena, Prodanović, Radivoje, Ilic-Durdic, Karla, Polović, Natalija, Spasojević, Milica, Prodanović, Olivera, "Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads" in Environmental Technology & Innovation, 21 (2021),
https://doi.org/10.1016/j.eti.2020.101211 . .

TY  - JOUR
AU  - Spasojević, Dragica
AU  - Prokopijević, Miloš
AU  - Prodanović, Olivera
AU  - Zelenović, Nevena
AU  - Polović, Natalija
AU  - Radotić, Ksenija
AU  - Prodanović, Radivoje
PY  - 2019
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1196
AB  - Derivatives of xylans were synthesized from corncob xylan by carboxymethylation, oxidization with different molar ratios of periodate (5, 10 15 and 20 mol%) and by reductive amination with tyramine. Modifications of tyramine carboxymethyl xylans (Tyr-CMX) were confirmed by FTIR, UV and NMR spectra. Concentration of ionizable groups increased from 1.5 mmol/g for carboxymethyl xylan (CMX) to 5.4 mmol/g for Tyr-CMX oxidized with 20 mol% of periodate. All Tyr-CMXs were able to form hydrogels the cross-linking reaction with horseradish peroxidase and peroxide. Tyr-CMXs were tested for amyloglucosidase (AG) encapsulation within hydrogel microbeads obtained in a reaction of emulsion polymerization with peroxidase. Average diameter of Tyr-CMX hydrogel microbeads was 52 +/- 25 mu m and after encapsulation optimization with respect to the extent of CMX modification with tyramine, the concentration of Tyr-CMX, and the amount of added AG, microbeads with AG specific activity of 2 U/mL and 20% yield of immobilization were obtained. The optimum pH of the immobilized AG was not changed compared to the soluble one, while half-life at 60 degrees C was increased around 10 times. The Michaelis-Menten constant for the immobilized enzyme, 1.03 mM, was significantly lower than that for the soluble one, 1.54 mM. After 5 cycles of repetitive use in batch reactor, the immobilized AG retained 68% of initial activity.
PB  - Polymer Soc Korea, Seoul
T2  - Macromolecular Research
T1  - Peroxidase-Sensitive Tyramine Carboxymethyl Xylan Hydrogels for Enzyme Encapsulation
EP  - 771
IS  - 8
SP  - 764
VL  - 27
DO  - 10.1007/s13233-019-7111-7
ER  - 

@article{
author = "Spasojević, Dragica and Prokopijević, Miloš and Prodanović, Olivera and Zelenović, Nevena and Polović, Natalija and Radotić, Ksenija and Prodanović, Radivoje",
year = "2019",
abstract = "Derivatives of xylans were synthesized from corncob xylan by carboxymethylation, oxidization with different molar ratios of periodate (5, 10 15 and 20 mol%) and by reductive amination with tyramine. Modifications of tyramine carboxymethyl xylans (Tyr-CMX) were confirmed by FTIR, UV and NMR spectra. Concentration of ionizable groups increased from 1.5 mmol/g for carboxymethyl xylan (CMX) to 5.4 mmol/g for Tyr-CMX oxidized with 20 mol% of periodate. All Tyr-CMXs were able to form hydrogels the cross-linking reaction with horseradish peroxidase and peroxide. Tyr-CMXs were tested for amyloglucosidase (AG) encapsulation within hydrogel microbeads obtained in a reaction of emulsion polymerization with peroxidase. Average diameter of Tyr-CMX hydrogel microbeads was 52 +/- 25 mu m and after encapsulation optimization with respect to the extent of CMX modification with tyramine, the concentration of Tyr-CMX, and the amount of added AG, microbeads with AG specific activity of 2 U/mL and 20% yield of immobilization were obtained. The optimum pH of the immobilized AG was not changed compared to the soluble one, while half-life at 60 degrees C was increased around 10 times. The Michaelis-Menten constant for the immobilized enzyme, 1.03 mM, was significantly lower than that for the soluble one, 1.54 mM. After 5 cycles of repetitive use in batch reactor, the immobilized AG retained 68% of initial activity.",
publisher = "Polymer Soc Korea, Seoul",
journal = "Macromolecular Research",
title = "Peroxidase-Sensitive Tyramine Carboxymethyl Xylan Hydrogels for Enzyme Encapsulation",
pages = "771-764",
number = "8",
volume = "27",
doi = "10.1007/s13233-019-7111-7"
}

Spasojević, D., Prokopijević, M., Prodanović, O., Zelenović, N., Polović, N., Radotić, K.,& Prodanović, R.. (2019). Peroxidase-Sensitive Tyramine Carboxymethyl Xylan Hydrogels for Enzyme Encapsulation. in Macromolecular Research
Polymer Soc Korea, Seoul., 27(8), 764-771.
https://doi.org/10.1007/s13233-019-7111-7

Spasojević D, Prokopijević M, Prodanović O, Zelenović N, Polović N, Radotić K, Prodanović R. Peroxidase-Sensitive Tyramine Carboxymethyl Xylan Hydrogels for Enzyme Encapsulation. in Macromolecular Research. 2019;27(8):764-771.
doi:10.1007/s13233-019-7111-7 .

Spasojević, Dragica, Prokopijević, Miloš, Prodanović, Olivera, Zelenović, Nevena, Polović, Natalija, Radotić, Ksenija, Prodanović, Radivoje, "Peroxidase-Sensitive Tyramine Carboxymethyl Xylan Hydrogels for Enzyme Encapsulation" in Macromolecular Research, 27, no. 8 (2019):764-771,
https://doi.org/10.1007/s13233-019-7111-7 . .

TY  - JOUR
AU  - Prokopijević, Miloš
AU  - Prodanović, Olivera
AU  - Spasojević, Dragica
AU  - Kovacević, Gordana
AU  - Polović, Natalija
AU  - Radotić, Ksenija
AU  - Prodanović, Radivoje
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1096
AB  - Pectin was modified by oxidation with sodium periodate at molar ratios of 2.5, 5, 10, 15 and 20 mol% and reductive amination with tyramine and sodium cyanoborohydride afterwards. Concentration of tyramine groups within modified pectin ranged from 54.5 to 538 mu mol/g of dry pectin while concentration of ionizable groups ranged from 3.0 to 4.0 mmol/g of dry polymer compared to 1.5 mmol/g before modification due to the introduction of amino group. All tyramine-pectins showed exceptional gelling properties and could form hydrogel both by cross-linking of carboxyl groups with calcium or by cross-linking phenol groups with peroxidase in the presence of hydrogen peroxide. These hydrogels were tested as carriers for soybean hull peroxidase (SHP) immobilization within microbeads formed in an emulsion based enzymatic polymerization reaction. SHP immobilized within tyramine-pectin microbeads had an increased thermal and organic solvent stability compared to the soluble enzyme. Immobilized SHP was more active in acidic pH region and had slightly decreased K (m) value of 2.61 mM compared to the soluble enzyme. After 7 cycles of repeated use in batch reactor for pyrogallol oxidation microbeads, immobilized SHP retained half of the initial activity.
PB  - Springer, New York
T2  - Applied Microbiology and Biotechnology
T1  - Tyramine-modified pectins via periodate oxidation for soybean hull peroxidase induced hydrogel formation and immobilization
EP  - 2290
IS  - 6
SP  - 2281
VL  - 101
DO  - 10.1007/s00253-016-8002-x
ER  - 

@article{
author = "Prokopijević, Miloš and Prodanović, Olivera and Spasojević, Dragica and Kovacević, Gordana and Polović, Natalija and Radotić, Ksenija and Prodanović, Radivoje",
year = "2017",
abstract = "Pectin was modified by oxidation with sodium periodate at molar ratios of 2.5, 5, 10, 15 and 20 mol% and reductive amination with tyramine and sodium cyanoborohydride afterwards. Concentration of tyramine groups within modified pectin ranged from 54.5 to 538 mu mol/g of dry pectin while concentration of ionizable groups ranged from 3.0 to 4.0 mmol/g of dry polymer compared to 1.5 mmol/g before modification due to the introduction of amino group. All tyramine-pectins showed exceptional gelling properties and could form hydrogel both by cross-linking of carboxyl groups with calcium or by cross-linking phenol groups with peroxidase in the presence of hydrogen peroxide. These hydrogels were tested as carriers for soybean hull peroxidase (SHP) immobilization within microbeads formed in an emulsion based enzymatic polymerization reaction. SHP immobilized within tyramine-pectin microbeads had an increased thermal and organic solvent stability compared to the soluble enzyme. Immobilized SHP was more active in acidic pH region and had slightly decreased K (m) value of 2.61 mM compared to the soluble enzyme. After 7 cycles of repeated use in batch reactor for pyrogallol oxidation microbeads, immobilized SHP retained half of the initial activity.",
publisher = "Springer, New York",
journal = "Applied Microbiology and Biotechnology",
title = "Tyramine-modified pectins via periodate oxidation for soybean hull peroxidase induced hydrogel formation and immobilization",
pages = "2290-2281",
number = "6",
volume = "101",
doi = "10.1007/s00253-016-8002-x"
}

Prokopijević, M., Prodanović, O., Spasojević, D., Kovacević, G., Polović, N., Radotić, K.,& Prodanović, R.. (2017). Tyramine-modified pectins via periodate oxidation for soybean hull peroxidase induced hydrogel formation and immobilization. in Applied Microbiology and Biotechnology
Springer, New York., 101(6), 2281-2290.
https://doi.org/10.1007/s00253-016-8002-x

Prokopijević M, Prodanović O, Spasojević D, Kovacević G, Polović N, Radotić K, Prodanović R. Tyramine-modified pectins via periodate oxidation for soybean hull peroxidase induced hydrogel formation and immobilization. in Applied Microbiology and Biotechnology. 2017;101(6):2281-2290.
doi:10.1007/s00253-016-8002-x .

Prokopijević, Miloš, Prodanović, Olivera, Spasojević, Dragica, Kovacević, Gordana, Polović, Natalija, Radotić, Ksenija, Prodanović, Radivoje, "Tyramine-modified pectins via periodate oxidation for soybean hull peroxidase induced hydrogel formation and immobilization" in Applied Microbiology and Biotechnology, 101, no. 6 (2017):2281-2290,
https://doi.org/10.1007/s00253-016-8002-x . .