TY  - CONF
AU  - Marković, Mirjana
AU  - Radmanović, Svjetlana
AU  - Čokeša, Đuro
AU  - Potkonjak, Nebojša
PY  - 2023
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/6690
AB  - Humic acids, belonging to the humic substances, are the most reactive organic compounds in water, soil and sediments. They are known for their role in processes related to soil structure, biology, and chemistry, as well as for their effects on the behavior of environmental pollutants. The effects of humic acids on the environment are strongly influenced by their composition and structure. Humic acids are
used in various fields, especially in agriculture, environmental remediation and medicine. Agricultural
fertilizers containing humic acids as additives are often used to improve plant growth and soil fertility.
The content of heavy metals, metalloids, radionuclides and various organic pollutants can be reduced
by adsorption, complexation, and redox processes involving humic acids. Owing to the ability of
humic acids to form composites with inorganic and organic oxides, pollutants are adsorbed and
removed from water. In addition, the composites formed exhibit pronounced antibacterial activity in
water. Various organic pollutants such as pesticides, microplastics and antibiotics can also be
removed from soil and water by adsorption on the composites or humic acids. Various viruses with
positively charged glycoproteins can be bound by the negatively charged humic acids, defining them
as antivirally active. Currently, the humic acids are isolated from various matrices such as coals, peat
and organic wastes. Due to the increasing requirements for the commercial applications of humic
acids, their production and utilization are significantly important and trendy tasks. The humic acid
production with the higher yield is the focus of research today.
PB  - University of Belgrade, Technical Faculty in Bor
C3  - 30th INTERNATIONAL CONFERENCE ECOLOGICAL TRUTH AND ENVIRONMENTAL RESEARCH – EcoTER’23, Serbia
T1  - HUMIC ACIDS IN THE ENVIRONMENT
EP  - 39
SP  - 30
UR  - https://hdl.handle.net/21.15107/rcub_agrospace_6690
ER  - 

@conference{
author = "Marković, Mirjana and Radmanović, Svjetlana and Čokeša, Đuro and Potkonjak, Nebojša",
year = "2023",
abstract = "Humic acids, belonging to the humic substances, are the most reactive organic compounds in water, soil and sediments. They are known for their role in processes related to soil structure, biology, and chemistry, as well as for their effects on the behavior of environmental pollutants. The effects of humic acids on the environment are strongly influenced by their composition and structure. Humic acids are
used in various fields, especially in agriculture, environmental remediation and medicine. Agricultural
fertilizers containing humic acids as additives are often used to improve plant growth and soil fertility.
The content of heavy metals, metalloids, radionuclides and various organic pollutants can be reduced
by adsorption, complexation, and redox processes involving humic acids. Owing to the ability of
humic acids to form composites with inorganic and organic oxides, pollutants are adsorbed and
removed from water. In addition, the composites formed exhibit pronounced antibacterial activity in
water. Various organic pollutants such as pesticides, microplastics and antibiotics can also be
removed from soil and water by adsorption on the composites or humic acids. Various viruses with
positively charged glycoproteins can be bound by the negatively charged humic acids, defining them
as antivirally active. Currently, the humic acids are isolated from various matrices such as coals, peat
and organic wastes. Due to the increasing requirements for the commercial applications of humic
acids, their production and utilization are significantly important and trendy tasks. The humic acid
production with the higher yield is the focus of research today.",
publisher = "University of Belgrade, Technical Faculty in Bor",
journal = "30th INTERNATIONAL CONFERENCE ECOLOGICAL TRUTH AND ENVIRONMENTAL RESEARCH – EcoTER’23, Serbia",
title = "HUMIC ACIDS IN THE ENVIRONMENT",
pages = "39-30",
url = "https://hdl.handle.net/21.15107/rcub_agrospace_6690"
}

Marković, M., Radmanović, S., Čokeša, Đ.,& Potkonjak, N.. (2023). HUMIC ACIDS IN THE ENVIRONMENT. in 30th INTERNATIONAL CONFERENCE ECOLOGICAL TRUTH AND ENVIRONMENTAL RESEARCH – EcoTER’23, Serbia
University of Belgrade, Technical Faculty in Bor., 30-39.
https://hdl.handle.net/21.15107/rcub_agrospace_6690

Marković M, Radmanović S, Čokeša Đ, Potkonjak N. HUMIC ACIDS IN THE ENVIRONMENT. in 30th INTERNATIONAL CONFERENCE ECOLOGICAL TRUTH AND ENVIRONMENTAL RESEARCH – EcoTER’23, Serbia. 2023;:30-39.
https://hdl.handle.net/21.15107/rcub_agrospace_6690 .

Marković, Mirjana, Radmanović, Svjetlana, Čokeša, Đuro, Potkonjak, Nebojša, "HUMIC ACIDS IN THE ENVIRONMENT" in 30th INTERNATIONAL CONFERENCE ECOLOGICAL TRUTH AND ENVIRONMENTAL RESEARCH – EcoTER’23, Serbia (2023):30-39,
https://hdl.handle.net/21.15107/rcub_agrospace_6690 .

TY  - JOUR
AU  - Jovanović, Uroš D.
AU  - Marković, Mirjana M.
AU  - Čokeša, Đuro M.
AU  - Živković, Nikola V.
AU  - Radmanović, Svjetlana B.
PY  - 2022
UR  - http://www.doiserbia.nb.rs/Article.aspx?ID=0352-51392200010J
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/6139
AB  - The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms.
T2  - Journal of the Serbian Chemical Society
T2  - Journal of the Serbian Chemical Society
T1  - Self-aggregation of soil humic acids with respect to their structural characteristics
EP  - 773
IS  - 6
SP  - 761
VL  - 87
UR  - https://hdl.handle.net/21.15107/rcub_agrospace_6139
ER  - 

@article{
author = "Jovanović, Uroš D. and Marković, Mirjana M. and Čokeša, Đuro M. and Živković, Nikola V. and Radmanović, Svjetlana B.",
year = "2022",
abstract = "The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms.",
journal = "Journal of the Serbian Chemical Society, Journal of the Serbian Chemical Society",
title = "Self-aggregation of soil humic acids with respect to their structural characteristics",
pages = "773-761",
number = "6",
volume = "87",
url = "https://hdl.handle.net/21.15107/rcub_agrospace_6139"
}

Jovanović, U. D., Marković, M. M., Čokeša, Đ. M., Živković, N. V.,& Radmanović, S. B.. (2022). Self-aggregation of soil humic acids with respect to their structural characteristics. in Journal of the Serbian Chemical Society, 87(6), 761-773.
https://hdl.handle.net/21.15107/rcub_agrospace_6139

Jovanović UD, Marković MM, Čokeša ĐM, Živković NV, Radmanović SB. Self-aggregation of soil humic acids with respect to their structural characteristics. in Journal of the Serbian Chemical Society. 2022;87(6):761-773.
https://hdl.handle.net/21.15107/rcub_agrospace_6139 .

Jovanović, Uroš D., Marković, Mirjana M., Čokeša, Đuro M., Živković, Nikola V., Radmanović, Svjetlana B., "Self-aggregation of soil humic acids with respect to their structural characteristics" in Journal of the Serbian Chemical Society, 87, no. 6 (2022):761-773,
https://hdl.handle.net/21.15107/rcub_agrospace_6139 .

TY  - CONF
AU  - Radmanović, Svjetlana
AU  - Marković, Mirjana
AU  - Živković, Nikola
AU  - Čokeša, Đuro
AU  - Jovanović, Uroš
AU  - Bogosavljević, Jelena
PY  - 2021
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/6650
AB  - Humic substances, including humic acids (HAs), are the most abundant fractions of soil organic matter. Their composition, structure and properties, determined by soil formation conditions, can be used as indicators of pedogenetic processes. In this study, elemental composition as very important part of HAs characterization was determined for humic acids isolated from the soils of Serbia developed under different pedogenetic conditions (Chernozem (CH), Smonica/Vertisol (VR), Rendzina/Regosol (RG), Pseudoglej/Planosol (PL) and Prelazni treset/Histosol (HI) and related to soil properties and origin. Soil samples were collected at 0 to 15-30 cm depth. Soil texture, organic C (soil organic matter for HI), and pH were determined by common methods. HA samples were isolated using a modified IHSS method. The C, H, and N contents of HA samples were determined using elemental analyzer (CHNS 628, LECO Corporation, USA) after drying the samples over P2O5 under vacuum. Their percentages were calculated on the ash-free basis. The oxygen content was obtained as the difference. The ash content was determined by a dry combustion method. The C/N, O/C, H/C and O/H atomic ratios were used as indicators of variations in HA properties as a function of HA origin. Internal oxidation degree (ω) was calculated by the equation: ω = (2O+3N-H)/C, where: O, N, H and C are element contents (atomic %). Elemental compositions of investigated HAs fall within the range of average values reported for soil HAs. According to the humification degree obtained, HAs studied are ranged as follows: CH>VR>RG>HI>PL. Both correlations done (H/C versus O/C and H versus C) separate HAs in three groups: CH and VR - the most dehydrogenated and demethylated, i.e. the most stable; RG - the most oxidated; and HI and PL - the most hydrogenated. HAs elemental composition is related to soil organic C and pH, but not related to soil clay. Internal oxidation degree is used as an indicator of plant residue humification progress. Positive ω values point out well drained soils with prevailing oxidizing conditions and negative values reflect anaerobic soil conditions. Internal oxidation degree values are obviously lower in hydromorphic HI and PL HAs compared to terrestrial RG, CH and VR HAs, but positive values indicate predominance of aerobic under anaerobic conditions in surface layer of hydromorphic soils. Results obtained in this study are in agreement with the literature data, indicating characteristics of HAs as particularly dependant on environmental conditions.
PB  - Serbian Society of Soil Science
C3  - 3rd International and 15th National Congress of Serbian Society of Soil Science: Soils for Future under Global Challenges, Sokobanja, Serbia
T1  - ELEMENTAL COMPOSITION OF HUMIC ACIDS ISOLATED FROM CHERNOZEM, VERTISOL, REGOSOL, PLANOSOL AND HISTOSOL
EP  - 70
SP  - 64
UR  - https://hdl.handle.net/21.15107/rcub_agrospace_6650
ER  - 

@conference{
author = "Radmanović, Svjetlana and Marković, Mirjana and Živković, Nikola and Čokeša, Đuro and Jovanović, Uroš and Bogosavljević, Jelena",
year = "2021",
abstract = "Humic substances, including humic acids (HAs), are the most abundant fractions of soil organic matter. Their composition, structure and properties, determined by soil formation conditions, can be used as indicators of pedogenetic processes. In this study, elemental composition as very important part of HAs characterization was determined for humic acids isolated from the soils of Serbia developed under different pedogenetic conditions (Chernozem (CH), Smonica/Vertisol (VR), Rendzina/Regosol (RG), Pseudoglej/Planosol (PL) and Prelazni treset/Histosol (HI) and related to soil properties and origin. Soil samples were collected at 0 to 15-30 cm depth. Soil texture, organic C (soil organic matter for HI), and pH were determined by common methods. HA samples were isolated using a modified IHSS method. The C, H, and N contents of HA samples were determined using elemental analyzer (CHNS 628, LECO Corporation, USA) after drying the samples over P2O5 under vacuum. Their percentages were calculated on the ash-free basis. The oxygen content was obtained as the difference. The ash content was determined by a dry combustion method. The C/N, O/C, H/C and O/H atomic ratios were used as indicators of variations in HA properties as a function of HA origin. Internal oxidation degree (ω) was calculated by the equation: ω = (2O+3N-H)/C, where: O, N, H and C are element contents (atomic %). Elemental compositions of investigated HAs fall within the range of average values reported for soil HAs. According to the humification degree obtained, HAs studied are ranged as follows: CH>VR>RG>HI>PL. Both correlations done (H/C versus O/C and H versus C) separate HAs in three groups: CH and VR - the most dehydrogenated and demethylated, i.e. the most stable; RG - the most oxidated; and HI and PL - the most hydrogenated. HAs elemental composition is related to soil organic C and pH, but not related to soil clay. Internal oxidation degree is used as an indicator of plant residue humification progress. Positive ω values point out well drained soils with prevailing oxidizing conditions and negative values reflect anaerobic soil conditions. Internal oxidation degree values are obviously lower in hydromorphic HI and PL HAs compared to terrestrial RG, CH and VR HAs, but positive values indicate predominance of aerobic under anaerobic conditions in surface layer of hydromorphic soils. Results obtained in this study are in agreement with the literature data, indicating characteristics of HAs as particularly dependant on environmental conditions.",
publisher = "Serbian Society of Soil Science",
journal = "3rd International and 15th National Congress of Serbian Society of Soil Science: Soils for Future under Global Challenges, Sokobanja, Serbia",
title = "ELEMENTAL COMPOSITION OF HUMIC ACIDS ISOLATED FROM CHERNOZEM, VERTISOL, REGOSOL, PLANOSOL AND HISTOSOL",
pages = "70-64",
url = "https://hdl.handle.net/21.15107/rcub_agrospace_6650"
}

Radmanović, S., Marković, M., Živković, N., Čokeša, Đ., Jovanović, U.,& Bogosavljević, J.. (2021). ELEMENTAL COMPOSITION OF HUMIC ACIDS ISOLATED FROM CHERNOZEM, VERTISOL, REGOSOL, PLANOSOL AND HISTOSOL. in 3rd International and 15th National Congress of Serbian Society of Soil Science: Soils for Future under Global Challenges, Sokobanja, Serbia
Serbian Society of Soil Science., 64-70.
https://hdl.handle.net/21.15107/rcub_agrospace_6650

Radmanović S, Marković M, Živković N, Čokeša Đ, Jovanović U, Bogosavljević J. ELEMENTAL COMPOSITION OF HUMIC ACIDS ISOLATED FROM CHERNOZEM, VERTISOL, REGOSOL, PLANOSOL AND HISTOSOL. in 3rd International and 15th National Congress of Serbian Society of Soil Science: Soils for Future under Global Challenges, Sokobanja, Serbia. 2021;:64-70.
https://hdl.handle.net/21.15107/rcub_agrospace_6650 .

Radmanović, Svjetlana, Marković, Mirjana, Živković, Nikola, Čokeša, Đuro, Jovanović, Uroš, Bogosavljević, Jelena, "ELEMENTAL COMPOSITION OF HUMIC ACIDS ISOLATED FROM CHERNOZEM, VERTISOL, REGOSOL, PLANOSOL AND HISTOSOL" in 3rd International and 15th National Congress of Serbian Society of Soil Science: Soils for Future under Global Challenges, Sokobanja, Serbia (2021):64-70,
https://hdl.handle.net/21.15107/rcub_agrospace_6650 .