Daniela Djikanovic

• PhD
• PhD at University of Belgrade

The surfaces of beech wood samples were treated with polyethylenimine (PEI) solutions at three different concentrations—0.5%, 1% and 2%—and two molecular weights—low molecular weight (LMW) and high molecular weight (HMW). The effects of PEI surface treatment of wood were characterized by FT-IR spectroscopy, the penetration depth of PEI (EPI fluores...

Silicon (Si) is a highly abundant mineral in Earth's crust. It plays a vital role in plant growth, providing mechanical support, enhancing grain yield, facilitating mineral nutrition, and aiding stress response mechanisms. The intricate relationship between silicification and lignin chemistry significantly impacts cell wall structure. Yet, the prec...

Simple Summary Fungi of the genus Trichoderma have a number of positive effects on plants that are manifested in the stimulation of plant growth and tolerance to abiotic and biotic stress factors. Our findings provide evidence for the swift response of tomato seeds to Trichoderma spp. exposure under in vitro conditions. The response was examined af...

In nature, woody substrates are usually degraded by entire communities of microorganisms, which are nowadays jeopardised by anthropogenic influence, making it important to define the functional specificity of every species. Two strains of autochthonous fungi from Serbian lowland forests (Pleurotus ostreatus Ser1 and Cyclocybe aegerita Ser1) have be...

Silicon (Si) is considered a beneficial element for plants, mostly accumulating in cell walls, where its location and content are primed by the chemistry and structure of lignin. It is unrevealed how Si interacts with the process of lignin formation in the CWs. We studied, in an in vitro system, the interaction of SiO2 with the peroxidase-catalyzed...

The effect of acetonitrile (ACN) on the micellization of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), in aqueous solutions at different temperatures was studied. The critical micellar concentration (CMC) as well as the degree of counter ion dissociation (a) of CTAB in aqueous ACN mixtures (10-20 % v/v) at various temperatures (291....

BACKGROUND Aflatoxin B1 (AFB1) is the most dangerous of the mycotoxins that contaminate cereal seeds naturally. A stress lignin formation is linked with the accumulation of reactive oxygen species causing a change in the redox status and formation of stable organic radicals, constituting the first layer of defense. The relationship between AFB1 and...

Due to the increasing environmental pollution caused by scrap tires, a solution is being sought to recycle and use them in a field of civil engineering, i.e., construction. This paper will provide a brief overview of previous researches that give detailed information on the advantages and disadvantages, considering the microstructural and mechanica...

Cellulose, xylan and lignin, as well as maize cell wall, were used as modifiers of carbon paste electrode. Comparative analysis of electrochemical performance of each modifier toward heavy metal detection was performed. A higher affinity of biomass constituents for lead ions than for copper ions influenced simultaneous detection of lead and copper...

We propose a sensitive and selective spectrofluorimetric method for the determination of flavonoids as expressed in ‘quercetin equivalent’ in apple juices. The method is based on the strong emission of the aluminium(III)-quercetin complex at 480 nm with excitation at 420 nm, and it is successfully applied for the determination of flavonoids in comm...

Interactions between macromolecules in the cell walls of different plant origin were compared, namely spruce wood (Picea omorika (Pančić) Purkiňe) as an example of softwood, maple wood (Acer platanoides L.) as a hardwood and maize stems (Zea mays L.) as a herbaceous plant from the grass family and widely used agricultural plant. Interactions of mac...

Key message Young P. omorika trees subjected to static bending showed a severe compression wood response as characterized by fluorescence spectroscopy/microscopy, which decreased in severity with height correlated with a decrease in bending moment. Abstract This investigation is aimed at understanding the reaction wood response in a slow-growing co...

Main conclusion: Cell wall fluorescence and immunocytochemistry demonstrate that xylem parenchyma cell walls do not show changes in structure and composition related to gravitropic response comparable to those of tracheids, even when they have lignified secondary cell walls. Tracheid cell walls in compression wood have altered composition and stru...

Due to the challenges of cell walls (biomass) and its applications in various new technologies, there is a need of rapid and reliable screening of fine variations in lignin structure. The in vitro synthesized lignin model polymers are good experimental system to relate lignin structure/properties with its applications. We used isoelectric focusing...

A simple, accurate and precise method based on the fluorescence properties of the aluminum(III)–quercetin complex, for the determination of quercetin, has been developed and validated. The complex has strong emission at pH 3.30, em = 480 nm, with ex = 420 nm. The linearity range of quercetin deter-mination was 1.5–60.5 ng ml–1 with LOD 0.09 ng ml...

The interactions of avarone, a quinone from the marine sponge Dysideaavara, and the methylamino derivatives of avarone (2), 3'-(methylamino)avarone (3) and 4'-(methylamino)avarone (4) with calf thymus DNA (CT-DNA) were studied. Agarose gel electrophoreticanalysis showed that binding of the quinones quenched fluorescence of ethidium bromide (EB).The...

Abstract: The spectrofluorometric method based on fluorescence ability of aluminium – hesperidin complex for the determination of hesperidin in orange juice is proposed. The linearity range of hesperidin inmethanolic-aqueous solution was 0.08 – 18.0 μg/mL with LOD and LOQ values as 0.023 μg/mL and 0.070 μg/mL, respectively, and recovery values...

In a plant cell wall, lignin is synthesized from several monomeric precursors, combined in various ratios. The variation in monomer type and quantity enables multifunctional role of lignin in plants. Thus, it is important to know how different combinations of lignin monomers impact variability of bond types and local structural changes in the polym...

Abstract: A fluorometric method, based on the fluorescence properties of the aluminium(III)–hesperidin complex, for the determination of hesperidin in hu- man plasma and pharmaceutical forms has been developed and validated. The complex shows a strong emission in the presence of the surfactant betain sul- phonate SB 12 at 476 nm with excitation a...

Export Date: 18 October 2014

U radu je predložena spektrofluorimetrijska metoda za određivanje sadržaja hesperidina u sokovima od pomorandže zasnovana na sposobnosti fluorescencije kompleksa aluminijum - hesperidin. Utvrđena je oblast linearnosti za određivanje hesperidina u metanolno-vodenim rastvora od 0.08 do 18.0 μg/mL, pri čemu je LOD= 0.023 μg/mL i LOQ= 0.070 μg/mL, a re...

The mechanical and physical properties of wood fibres are dependent on the organisation of their constituent polymers (cellulose, hemicellulose and lignin). Fourier Transform Infrared (FTIR) microscopy was used to examine the anisotropy of the main wood polymers in isolated cell wall fragments from branches of maple and Serbian spruce. Polarised FT...

Morin is a flavonol antioxidant. In ethanol – water mixtures (70 wt % of ethanol) it reacts with Al 3+ to give Al(Morin)2 in the pH range 3–6. The conditional stability constant of this complex at 298 K was found to be log β2 = 16.96 ± 0.02 at pH 4.40. The complex shows strong fluorescence emission at 500 nm upon excitation at 410 nm. The fluoresce...

Confocal fluorescence microscopy was used to examine the spectral characteristics of lignin autofluorescence in secondary cell walls of normal and compression wood from Pinus radiata. Using UV excitation, fluorescence spectra of normal and compression wood sections showed significant differences, especially in the outer secondary cell wall of trach...

We used an atomic force microscope to image cell wall isolated from needles of Serbian spruce tree and that synthesized from cell wall components. We also observed the structure of lignin model polymer (DHP), as a best substitute for the natural lignin. A tendency of aggregate formation was observed in all samples. Cell wall was revealed as a lamin...

Morin is a flavonol antioxidant. In ethanol - water mixtures (70 wt % of ethanol) it reacts with Al3+ to give Al(Morin)2 in the pH range 3-6. The conditional stability constant of this complex at 298 K was found to be log β2 = 16.96 ± 0.02 at pH 4.40. The complex shows strong fluorescence emission at 500 nm upon excitation at 410 nm. The fluorescen...

In this work, we deconvoluted the fluorescence spectra of lignin and a lignin model compound using a combination of one symmetric (Gaussian) and the most appropriate number of asymmetric (Log-normal) models. We aimed to obtain new data on the structural characteristics of lignin as a complex molecule using fluorescence spectroscopy in combination w...

Having a valid mathematical model for structureless emission band shapes is important when deconvoluting fluorescence spectra of complex molecules. We propose a new asymmetric model for emission spectra of five organic molecules containing aromatic ring: catechol, coniferyl alcohol, hydroquinone, phenylalanine and tryptophan. For each molecule, a s...

Fluorescence spectroscopy is a sensitive analytical tool in the studies of both simple and complex molecular structures. In complex molecules, however, determining the number and position of components may give a specific insight into the structure, complementary to the other analytical techniques. We applied log-normal model to analyze fluorescenc...

We analyzed low molecular mass phenolics, lignin content and both soluble and cell wall bound peroxidase activity in the needles of three Picea omorika (Pancic) Purkyne lines grown in the generative seed orchard. The highest values of the total phenol content as well as of catechine, caffeic acid, coniferyl alcohol, isoferulic acid and lignin conce...

In order to test whether lignin fluorescence originates from discrete fluorophores, fluorescence emission spectra of the lignin model dehydrogenative polymer (DHP) were analyzed by the band deconvolution method and time-resolved analysis of both the excitation and emission spectra. Two series of 22 fluorescence emission spectra of DHP in chloroform...

In this paper, we present a nanoscale study of the supramolecular structure of the dehydrogenate polymer (ZL-DHP) lignin model compound. The combination of near-field scanning optical microscopy (NSOM or SNOM) and atomic force microscopy (AFM) has been utilized to explore physicochemical properties of the lignin model compound on a scale ranging fr...