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Copper is one of the leading metal pollutants in the water, which can cause adverse effects when present in high concentrations. The Daphnia magna is a model organism usually used for the determination of ecotoxicological effects of various compounds since it is highly sensitive to toxic compounds [1]. The aim of this work was to investigate the potential application of microbial extracellular polysaccharides (EPS), levan and pullulan, as agents for reducing the copper toxicity to D. magna. The protective effects of EPS were estimated based on the accumulation of copper in the D. magna cells. Levan is a branched fructane EPS [2] and the one used in this study was produced by Bacillus licheniformis NS032. Pullulan, a linear glucan EPS [3], was produced by Aureobasidium pullulans CH-1. The D. magna were exposed to 50 µg/dm3 of Cu (II) or a combination with 50 mg/dm3 and 100 mg/dm3 of levan or pullulan for 48h in the acute test. Additionally, the prolonged test was performed, where the daphnia were exposed to a 10 µg/dm3 of Cu (II) with or without 50 mg/ dm3 of levan or pullulan for 5 days. After the exposure period, the samples were digested and the accumulation of copper in D. magna was analysed using the iCAP Qc ICP-MS (Thermo Scientific, United Kingdom). The results showed that animals exposed to Cu (II) only, accumulated Cu (II) in a greater amount after the prolonged test compared to the acute one, despite the lower concentration. The treatment with EPS during the acute test increased the copper accumulation for both EPS concentrations tested, whereas during the prolonged exposure test, the Cu (II) accumulation was inhibited. Considering that protective effects of levan and pullulan were observed only with lower copper concentrations and 5 days of exposure, additional experiments are necessary to determine the mechanism of EPS action in order to confirm their possible use as protective agents.

The aim of this study is to synthesize PANI/pullulan composites using microwave radiation and investigate their microbial activity.

Aquaphotomics is a relatively novel scientific discipline which can be used for elucidation of structural and related functional properties of aqueous systems. The aim of this study was to analyse water solutions of carbohydrates of different size from monosaccharides (glucose and fructose) via, disaccharides (sucrose), gluco and fructo-oligosaccharides and various selected polisaccharides (based on glucose and fructose, respectively) using Aquaphotomics. Knowing that main functions of carbohydrates within our body are various: providing energy and regulation of blood glucose; sparing the use of proteins for energy; breakdown of fatty acids and preventing ketosis; biological recognition processes; flavor and sweeteners and dietary fibers who can promote digestive health, knowledge about their interaction with water molecules can have strong influence on our understanding of some basic but also complex metabolic processes.

This study investigated potential effects of microbial levan and pullulan for reducing copper toxicity in model organism Daphnia magna using Micro-Oxymax respirometer. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5178]

Pullulan based films were prepared with crude extracts of cinnamon and oregano spices. Obtained films were characterized by FTIR-ATR spectroscopy and their antioxidant and antimicrobial properties were evaluated. These biopolymer based films have potential use in food applications as food ingredients and active packaging material. 6th Workshop Specific Methods for Food Safety and Quality, 27.09.2018. Belgrade, Serbia

In this work, pullulan based films with water extracts of medicinal herbs thyme and sage, were prepared. The resulting films were characterized by FT-IR spectroscopy and their antioxidant and antimicrobial activities were evaluated. These products have potential use in food applications, as a supplement to functional food and/or as coatings for food packaging material.

Production, purification and partial characterization of obtained polysaccharide production optimization by response surface method is presented. Prikazana je produkcija, prečišćavanje i parcijalna karakterizacija dobijenog polisaharida; optimizacija proizvodnje pululana pomoću metode odzivnih površina. Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5256]

The aim of the present work was the synthesis of silver nanoparticles based on periodate oxidazed pullulan and investigation thus obtained material as an antibacterial agent. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5287]

A chromogenic substrate was obtained by coupling azo dye Congo red to microbial polysaccharide pullulan. The synthesized product was characterized by spectral techniques and elemental analysis. Results showed that dye-labelled glycan can be successfully used for the screening of microorganisms possessing enzymes that selectively catalyze the cleavage of glycosidic linkages characteristic for this polysaccharide.