Marko Jonovic - Academia.edu (original) (raw)

Papers by Marko Jonovic

Catalysts, Feb 26, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Catalysts

Enzymatic hydrolysis of food proteins is convenient method to improve their functional properties... more Enzymatic hydrolysis of food proteins is convenient method to improve their functional properties and physiological activity. Herein, the successful covalent attachment of alcalase on alginate micron and submicron beads using the carbodiimide based chemistry reaction and the subsequent application of the beads for egg white and soy proteins hydrolysis were studied. In addition to the electrostatic extrusion technique (EE) previously used by others, the potential utilization of a novel ultrasonic spray atomization technique without drying (UA) and with drying (UAD) for alginate submicron beads production has been attempted. The immobilization parameters were optimized on microbeads obtained by EE technique (803 ± 23 µm) with respect to enzyme loading and alcalase activity. UA and UAD techniques resulted in much smaller particles (607 ± 103 nm and 394 ± 51 nm in diameter, respectively), enabling even higher enzyme loading of 671.6 ± 4 mg g−1 on the carrier and the highest immobilized ...

For more than a century of mining in the municipality of Bor, various mining and metallurgical ac... more For more than a century of mining in the municipality of Bor, various mining and metallurgical activities, degradation of thousands of hectares of forests and fields. It is estimated that up to now in Bor and its surroundings have been excavated over 200 million tons of ore and 500 million tons of overburden, where he produced about 195 million tons of tailings. Deferred mining waste disposal from the moment onwards, under the influence of environmental factors is an ongoing source of acid waters carry dissolved heavy metals and pollute the surrounding soil, surface water and groundwater. Due to the continuous occurrence of acid solutions appears constant negative impact on surface and ground water flows as well as their watersheds. The paper analyzes the actual state of endangered locations and their categorization according to the degree of contamination of harmful elements.

Biotechnology Letters, 2006

Horseradish peroxidase (HRP) was immobilized on carboxylated multi-wall carbon nanotubes in the p... more Horseradish peroxidase (HRP) was immobilized on carboxylated multi-wall carbon nanotubes in the presence of a coupling reagent, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The immobilized HRP maintained its oxidative activity for guaiacol over a broad range of pH values (4-9). An electrode of graphite rod, 6 mm diam. was fabricated using the immobilized HRP. Cyclic voltammetry of the enzyme electrode confirmed electron transfer between the immobilized HRP and the electrode in the presence of H2O2 but without an added mediator or a reducing substrate.

Bioprocess and biosystems engineering, Jan 11, 2017

In this study, alcalase (protease from Bacillus licheniformis) immobilization by adsorption, enzy... more In this study, alcalase (protease from Bacillus licheniformis) immobilization by adsorption, enzyme crosslinking and covalent enzyme binding to activated chitosan microbeads were examined. The biocatalysts highest activity was obtained by covalent immobilization of alcalase onto a solid support. The alcalase covalent immobilization onto different types of chitosan beads obtained by inverse emulsion technique and electrostatic extrusion was studied. Parameters examined under different conditions were beads diameter, enzyme loading, enzyme capacity yield, and biocatalyst activity. The highest activity and enzyme loading of 23.6 IU/mg protein and 340.2 mg/g, respectively, were achieved by the enzyme immobilized onto chitosan microbeads obtained by the electrostatic extrusion technique. FT-IR analysis was used to confirm formation of alcalase-chitosan conjugates. The activity of optimally produced alcalase-chitosan microbeads was then verified in the industrially feasible reaction syste...

Mining and Metallurgy Engineering Bor, 2014

The off-balance resources present the environmental problem and potential resource for copper ext... more The off-balance resources present the environmental problem and potential resource for copper extraction. This paper presents the results obtained using different reagents for the process of sulphide form oxidation of copper from flotation tailings. For the investigation in this paper work, the samples of flotation tailings were taken from the Old Flotation Tailing Dump of the Mining and Smelting Complex Bor in Eastern Serbia. Experimental testing was carried out in order to increase the leaching degree of copper with addition of oxidants during leaching. Using the Fe 2 (SO 4) 3 as an oxidant, the achieved copper leaching degree was 76.8%. The effect of thermal destruction of sulfide copper from flotation tailings in the presence of concentrated sulfuric acid was also investigated. After leaching of calcine with water, the degree of copper leaching was attained of 92%. Solutions after leaching are suitable for the SX-EW process of obtaining the copper.

Zastita materijala, 2016

Production process of copper obtaining in the Mining and Smelting Company (RTB) Bor directly affe... more Production process of copper obtaining in the Mining and Smelting Company (RTB) Bor directly affects the environmental pollution in Bor and surrounding area. Harmful elements present in the air are deposited on the surface and due to the effects of atmospheric precipitation penetrate into deeper layers of soil. On the other hand, in the area of RTB Bor activity, the significant pollution of rivers and soil are present in coastal area due to the increased concentrations of present heavy metals. The Bor River is particularly endangered where the waste industrial and mining waste water flew for many years. The Bor River has become on time one of the most polluted rivers in Europe. This paper presents the results of physico-chemical characterization of soil samples from the coastal areas of the Bor River. The following parameters were analyzed: moisture content, pH value, bulk density, specific gravity, grain size distribution, chemical composition, toxic characteristics-TCLP Method and leaching test-Method for characterization of waste leaching. The obtained results indicate that the soil is contaminated with heavy metals and that a significant deviation from the permissible concentrations was found in particular for the following elements: Cu, As, and Pb. The soil in the coastal area of the Bor River belongs to the category of hazardous waste and the preventive measures are necessary in accordance with defined regulations.

Bioprocess and Biosystems Engineering