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Degradacija betona može da bude posledica različitih fizičkih promena kao što su korozija, pucanje, preopterećenje itd. Osim fizičkih promena, na izdržljivost betona mogu da utiču i mikroorganizmi u procesu biodeterioracije. Iako biodeterioracija retko može biti direktan uzrok degradacije, ona znatno ubrzava druge štetne procese kao što su prodor hlorida i karbonacija koji narušavaju strukturu betona [1]. U procesima biodeterioracije mogu da učestvuju različiti mikroorganizmi kao što su bakterije, gljive, alge, lišajevi [2]. Oni utiču na procese deterioracije betona na tri načina: narušavanjem izgleda, što je posledica formiranja biofilma, mehaničkim pucanjem usled rasta i kretanja mikroorganizama i hemijskim putem usled ekskrecije metabolita [3]. Na početku, pH betonske površine je veoma visoka, pa će, ukoliko je vlažnost i količina hranljivih supstanci dovoljna, doći do kolonizacije alkalifilnim i tionskim bakterijama. Produkcijom oksidovanih sumpornih jedinjenja snižava se pH vrednost što povećava kolonizaciju betonske površine neutrofilnim, a potom i acidofilnim mikroorganizmima. Osim promene pH vrednosti, kiseline koje se proizvode direktno utiču na strukturni integritet betona pošto razgrađuju cementni materijal [2]. Usled deterioracije, troškovi održavanja betonskih konstrukcija je povećavaju, što svake godine prouzrokuje znatnu ekonomsku štetu [1, 2, 3]. U okviru ove studije ispitivan je odnos između mikrobnog rasta i različitih hemijskih svojstava uzoraka poreklom iz tri hidroelektrane u Srbiji (HE Đerdap, HE Potpeć, HE Uvac). Uzorkovanje je radjeno na dva mesta na svakoj lokaciji. Ispitivan je broj ukupnih, gvožđevitih, sulfat-redukujućih i tionskih bakterija, kvasaca i plesni kao i pH vrednost i sadržaj sulfata, nitrata, hlorida, mangana, gvožđa, magnezijuma i kalcijuma. Vrednosti pH su bile u opsegu od 8,39- 9,09, koncentracije gvožđa su bile između 151,0- 61.100,0 mg/L, mangana 7,2- 4.900,0 mg/L, sulfata 37,4- 623,7 mg/L, nitrata 1,0- 11,3 mg/L, hlorida 88,2- 1.104,2 mg/L, kalcijuma 5,48- 19,93% i magnezijuma 0,11- 1,26%. Maksimalan broj ukupnih bakterija je bio 6,24x108 cfu/g, kvasaca i plesni 3,12x105 cfu/g, sulfat redukujućih bakterija 2,20x103 cfu/g , tionskih bakterija 2,50x104 cfu/g, a gvožđevitih bakterija 6.4 x 106 cfu/g. Broj mikroorganizama i njihova aktivnost se uobičajeno povezuje sa osnovnim fizičko-hemijskim i hemijskim karakteristikama ispitivanih uzoraka. Hemijski faktori se u ovim uzorcima znatno razlikuju u zavisnosti od mesta uzorkovanja, zbog čega nije moguće odrediti jedan faktor koji bi bio indikator biodeterioracije. Ipak, uzorci uzeti iz HE Đerdap imaju najveći broj tionskih i sulfat-redukujućih bakterija, kao i najveću koncentraciju hlorida. Jedan od uzoraka uzetih iz HE Potpeć imao je najniži broj svih određivanih mikroorganizama kao i ekstremno visoke koncentracije gvožđa i mangana.

In this work, the determination of different physiological-biochemical groups of microorganisms from sediment on a general and selective medium is presented. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5028]

Degradacija betona može da bude posledica različitih fizičkih promena kao što su korozija, pucanje, preopterećenje itd. Osim fizičkih promena, na izdržljivost betona mogu da utiču i mikroorganizmi u procesu biodeterioracije. Iako biodeterioracija retko može biti direktan uzrok degradacije, ona znatno ubrzava druge štetne procese kao što su prodor hlorida i karbonacija koji narušavaju strukturu betona [1]. U procesima biodeterioracije mogu da učestvuju različiti mikroorganizmi kao što su bakterije, gljive, alge, lišajevi [2]. Oni utiču na procese deterioracije betona na tri načina: narušavanjem izgleda, što je posledica formiranja biofilma, mehaničkim pucanjem usled rasta i kretanja mikroorganizama i hemijskim putem usled ekskrecije metabolita [3]. Na početku, pH betonske površine je veoma visoka, pa će, ukoliko je vlažnost i količina hranljivih supstanci dovoljna, doći do kolonizacije alkalifilnim i tionskim bakterijama. Produkcijom oksidovanih sumpornih jedinjenja snižava se pH vrednost što povećava kolonizaciju betonske površine neutrofilnim, a potom i acidofilnim mikroorganizmima. Osim promene pH vrednosti, kiseline koje se proizvode direktno utiču na strukturni integritet betona pošto razgrađuju cementni materijal [2]. Usled deterioracije, troškovi održavanja betonskih konstrukcija je povećavaju, što svake godine prouzrokuje znatnu ekonomsku štetu [1, 2, 3]. U okviru ove studije ispitivan je odnos između mikrobnog rasta i različitih hemijskih svojstava uzoraka poreklom iz tri hidroelektrane u Srbiji (HE Đerdap, HE Potpeć, HE Uvac). Uzorkovanje je radjeno na dva mesta na svakoj lokaciji. Ispitivan je broj ukupnih, gvožđevitih, sulfat-redukujućih i tionskih bakterija, kvasaca i plesni kao i pH vrednost i sadržaj sulfata, nitrata, hlorida, mangana, gvožđa, magnezijuma i kalcijuma. Vrednosti pH su bile u opsegu od 8,39- 9,09, koncentracije gvožđa su bile između 151,0- 61.100,0 mg/L, mangana 7,2- 4.900,0 mg/L, sulfata 37,4- 623,7 mg/L, nitrata 1,0- 11,3 mg/L, hlorida 88,2- 1.104,2 mg/L, kalcijuma 5,48- 19,93% i magnezijuma 0,11- 1,26%. Maksimalan broj ukupnih bakterija je bio 6,24x108 cfu/g, kvasaca i plesni 3,12x105 cfu/g, sulfat redukujućih bakterija 2,20x103 cfu/g , tionskih bakterija 2,50x104 cfu/g, a gvožđevitih bakterija 6.4 x 106 cfu/g. Broj mikroorganizama i njihova aktivnost se uobičajeno povezuje sa osnovnim fizičko-hemijskim i hemijskim karakteristikama ispitivanih uzoraka. Hemijski faktori se u ovim uzorcima znatno razlikuju u zavisnosti od mesta uzorkovanja, zbog čega nije moguće odrediti jedan faktor koji bi bio indikator biodeterioracije. Ipak, uzorci uzeti iz HE Đerdap imaju najveći broj tionskih i sulfat-redukujućih bakterija, kao i najveću koncentraciju hlorida. Jedan od uzoraka uzetih iz HE Potpeć imao je najniži broj svih određivanih mikroorganizama kao i ekstremno visoke koncentracije gvožđa i mangana.

Vodeni organizmi su izloženi brojnim hemijskim supstancama različitih mehanizama toksičnosti i da bi se okarakterisali međusobni efekti važna je uporedna analiza hemijskih podataka i odgovarajućeg biološkog odgovora (biomarkeri) [1]. Slatkovodni, planktonski beskičmenjak Daphnia magna je dobro poznat model u ekotoksikologiji, zbog svoje visoke osetljivosti na toksične supstance i relativno lake kultivacije u laboratorijskim uslovima. Većina istraživanja o proceni toksičnosti različitih hemijskih supstanci bazira se na ispitivanju akutne toksičosti i letalne ili efektivne koncentracije supstance koje dovode do neželjenog efekta u 50 % slučajeva (LC50/EC50), međutim neophodne su i detaljnije informacije o toksičnosti, koje bi uključile subletalne efekte i senzitivnije biomerkere [2]. Pošto bakar i njegova jedinjenja spadaju u vodeće zagađujuće supstance vode, sprovedene su i evaluirane brojne procene njegovih opasnosti i/ili negativnih efekata (US EPA 2007;EU 2007) [3]. Homeostaza bakra u akvatičnim organizmima uključuje regulisan unos,transport i ekskreciju koja je slična kao kod sisara. Studije na D. magna, koje su bile izložene subletalnim koncentracijama bakra, pokazuju pojačan oksidativni stres u jedinkama [4]. U ovoj studiji praćena je potrošnja O2 i produkcija CO2 kod jedinki D. magna tokom 48 h izlaganja Cu2+ jonima. Respiracija D. magna (MicroBioTests Inc.) neonata praćena je 48 h pomoću dvanaestokanalnog Micro-Oxymax respirometra (Columbus Instruments, SAD). U intervalima od 4 h merena je koncentracija O2, paramagnetnim senzorom, a CO2 infracrvenim senzorom, pri čemu je tokom celokupnog trajanja eksprerimenta sistem bio zatvoren. Uzorci su pripremani u providnim Micro-Oxymax bocama zapremine 500 mL u kojima je bilo po 100 mL tečne podloge i 20 neonata. Korišćen je AdaM medijum (Aachener Daphnien Medium) [5]. Koncentracija Cu2+ jona bila je 50 μg/mL i odabrana je prema literaturno određenoj EC50 vrednosti za CuSO4 [6]. Jedinke nisu hranjene tokom eksperimenta i izlagane su na temperaturi od 20±2 ºC i fotoperiodu 16 h dan/8 h noć. Dobijeni podaci su evaluirani Micro-Oxymax softverom i određena je kumulativna potrošnja/proizvodnja gasova (μL). Nakon izlaganja praćena je imobilizacija neonata, a rezultati su izraženi kao procenat mortaliteta. Dva dana nakon izlaganja D. magna sa Cu2+ jonima, zabeležen je mortalitet jedinki od 75 %. Test je bio validan, jer nije zabeležen mortalitet u kontrolnoj grupi. Kod organizama koji su bili izloženi jonima bakra kumulativna potrošnja O2 je znatno manja tokom celog eksperimenta, dok je kumulativna produkcija CO2 u prvih 24 h manja, a dalje razlike nisu uočene, što se može pripisati dekompoziciji imobilisanih jedinki. Na osnovu dobijenih rezultata zaključeno je da se test na MicroOxymax respirometru može koristiti kao dodatni parametar za procenu akutnih efekata toksičnih susptanci na organizam D. magna.

The aim of this research was to investigate the overall dynamics and the efficiency of biodegradation of saturated and aromatic compounds – constituents of the oil pollutant, during ex situ bioremediation of the polluted soil. The effect of natural biodegradation was investigated in a parallel set of samples of the same soil which was not subjected to the processes of stimulation (bioaugmentation, biostimulation and aeration). During the period of six months, the biodegradation process caused a gradual and prominent degradation of phenanthrene, dibenzothiophene, fluoranthene/pyrene and their alkyl homologues. Among the polycyclic aromatic hydrocarbons (PAHs), distributions and abundances of benz(a)anthracene/chrysenes and triaromatic steroids were the least affected by biodegradation. n-Alkanes and isoprenoids remained low in abundances during and until the end of the experiment, indicating that the availability, rather than the biodegradability, was responsible for removal of these compounds. In the set of the samples exposed to the stimulated bioremediation, within the homologue series of phenanthrenes, dibenzothiophenes and fluoranthene/pyrenes, higher alkylated homologues were more degradable than the lower ones. Additionally, lower alkylated homologues were more degradable than their parent molecules. These results are opposite to those described in the literature and indicate that a proper choice of bioremediation conditions can influence biodegradation sequences of the compounds present in the pollutant. Furthermore, these results showed that the extent of biodegradation in the samples exposed to stimulation was much higher than in the samples where only natural biodegradation occurred, pointing that the stimulated biodegradation is much more efficient process than the natural biodegradation.

In this paper influence of the low frequency magnetic field on Saccharomyces cerevisiae respiration was examined. Influence of four low frequency magnetic field ranges was examined: 10-200 Hz, 200-300 Hz, 300-650 Hz and 650-1000 Hz. All analyzed frequency ranges gave the same influence on the yeast cells respiration.

The effects of electric, magnetic or electromagnetic fields on different microbes have become a very popular topic nowadays, mostly because the fields could potentially affect the survival of the microbial cells as well as their behavior and metabolism. In this paper the influence of the magnetic field with constant low frequency scan regime from 10 to 1000 Hz on yeast cells S. cerevisiae respiration activity was examined using Micro-Oxymax® respirometer. Experiments were performed in five replicates. All five experiments showed lower cumulative O2 consumption in magnetic field exposed samples, compared to the control sample and inconsistent cumulative CO2 production. The paired two sample onetail T-test showed statistically significant differences between control and magnetic field sample for cumulative O2 consumption, but not for the CO2 production. Even though additional experiments are neccesary to clarify the differencies in CO2 production, these preliminary findings strongly suggest that obtained results represent a good basis for further investigations in this field. Veoma popularna tema današnjice je ispitivanje električnog, magnetnog i elektromagnetnog polja na različite mikroorganizme, jer pomenuta fizička polja potencijalno deluju kao faktori stresa i tako utiču na njihovo preživljavanje, ponašanje i metabolizam. U ovom radu ispitivan je uticaj niskofrekventnog magnetnog polja sa konstantnim intervalom skeniranja od 10 do 1000 Hz na respiraciju ćelija kvasca, Saccharomyces cerevisiae. Eksperimenti su rađeni u pet ponavljanja i kumulativna potrošnja O2 i produkcija CO2 praćena je pomoću Micro-Oxymax® respirometra. U svih pet ponavljanja, ćelije koje su bile izložene magnetnom polju pokazale su manju kumulativnu potrošnju kiseonika u poređenju sa uzorcima van magnetnog polja i nekonzistentnu produkciju CO2. Rezultati su obrađeni uporednim jednosmernim T-testom, koji je pokazao da postoje statistički značajne razlike u kumulativnoj potrošnji O2 između kontrolnih ćelija i onih izloženih magnetnom polju, što nije slučaj sa kumulativnom produkcijom CO2. Iako su dodatna ispitivanja neophodna da se objasni nekonzistentnost produkcije CO2, dobijeni rezultati ovih inicijalnih eksperimenata predstavljaju dobru osnovu za dalja istraživanja u ovoj oblasti.

The numerous naturally occurring biopolymeric materials are used as edible films and coatings (lipids, proteins, and polysaccharides). Microbial levan and pullulan have been already considered as biopolymers in food industry. The aim of this work was to obtain the levan and levan/pullulan blend films and compare them using the Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). Two different films compositions were prepared by casting method: levan and levan/pullulan in the proportions 1:1. AFM measurements showed that levan film had a smoother surface and, consequently, a lower degree of roughness comparing to the levan/pullulan blend films. FTIR spectra showed peaks, which corresponded to all components of the obtained films. Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5427]

In the present study, graft copolymer with microbial levan and styrene was synthetized, characterized and its biodegradable potential was investigated. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5194]

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

Until recently, we considered natural recycling capacities unlimited. However, industrial development, usage of fossil fuels and production of manmade compounds has led to the situation were the amount of generated waste is exceeding the capacity of nature for self-purification. For this purpose to clean up polluted areas, a number of methods have been developed and applied: chemical, physical, physico-chemical, in order to extract, control, and transform the harmful substances. However, it is characteristic that for most of the methods currently in use, as a result of their use, waste that requires controlled disposal is generated. One of the technologies that have achieved remarkable success in the world in terms of remediation of oil pollution is bioremediation - cleaning and curing primarily soil, as well as other ecosystems. This is the most natural method of remediation, which use non-pathogenic microorganisms for which pollutants represent food. In this way, by the action of microorganisms naturally present in the soil, pollutants are transformed into substances that have no toxic effects on humans and the environment, and then completely mineralized to carbon dioxide, water and biomass of microorganisms. It is confirmed that the best microorganisms for bioremediation are those already present at the polluted site that needs to be remediated.

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.

Vodeni organizmi su izloženi brojnim hemijskim supstancama različitih mehanizama toksičnosti i da bi se okarakterisali međusobni efekti važna je uporedna analiza hemijskih podataka i odgovarajućeg biološkog odgovora (biomarkeri) [1]. Slatkovodni, planktonski beskičmenjak Daphnia magna je dobro poznat model u ekotoksikologiji, zbog svoje visoke osetljivosti na toksične supstance i relativno lake kultivacije u laboratorijskim uslovima. Većina istraživanja o proceni toksičnosti različitih hemijskih supstanci bazira se na ispitivanju akutne toksičosti i letalne ili efektivne koncentracije supstance koje dovode do neželjenog efekta u 50 % slučajeva (LC50/EC50), međutim neophodne su i detaljnije informacije o toksičnosti, koje bi uključile subletalne efekte i senzitivnije biomerkere [2]. Pošto bakar i njegova jedinjenja spadaju u vodeće zagađujuće supstance vode, sprovedene su i evaluirane brojne procene njegovih opasnosti i/ili negativnih efekata (US EPA 2007;EU 2007) [3]. Homeostaza bakra u akvatičnim organizmima uključuje regulisan unos,transport i ekskreciju koja je slična kao kod sisara. Studije na D. magna, koje su bile izložene subletalnim koncentracijama bakra, pokazuju pojačan oksidativni stres u jedinkama [4]. U ovoj studiji praćena je potrošnja O2 i produkcija CO2 kod jedinki D. magna tokom48 h izlaganja Cu2+ jonima. Respiracija D. magna (MicroBioTests Inc.) neonata praćena je 48 h pomoću dvanaestokanalnog Micro-Oxymax respirometra (Columbus Instruments, SAD). U intervalima od 4 h merena je koncentracija O2, paramagnetnim senzorom, a CO2 infracrvenim senzorom, pri čemu je tokom celokupnog trajanja eksprerimenta sistem bio zatvoren. Uzorci su pripremani u providnim Micro-Oxymax bocama zapremine 500 mL u kojima je bilo po 100 mL tečne podloge i 20 neonata. Korišćen je AdaM medijum (Aachener Daphnien Medium) [5]. Koncentracija Cu2+ jona bila je 50 μg/mL i odabrana je prema literaturno određenoj EC50 vrednosti za CuSO4 [6]. Jedinke nisu hranjene tokom eksperimenta i izlagane su na temperaturi od 20±2 ºC i fotoperiodu 16 h dan/8 h noć. Dobijeni podaci su evaluirani Micro-Oxymax softverom i određena je kumulativna potrošnja/proizvodnja gasova (μL). Nakon izlaganja praćena je imobilizacija neonata, a rezultati su izraženi kao procenat mortaliteta. Dva dana nakon izlaganja D. magna sa Cu2+ jonima, zabeležen je mortalitet jedinki od 75 %. Test je bio validan, jer nije zabeležen mortalitet u kontrolnoj grupi. Kod organizama koji su bili izloženi jonima bakra kumulativna potrošnja O2 je znatno manja tokom celog eksperimenta, dok je kumulativna produkcija CO2 u prvih 24 h manja, a dalje razlike nisu uočene, što se može pripisati dekompoziciji imobilisanih jedinki. Na osnovu dobijenih rezultata zaključeno je da se test na MicroOxymax respirometru može koristiti kao dodatni parametar za procenu akutnih efekata toksičnih susptanci na organizam D. magna.

Development of innovative granular micro-composite fertilizers based on vermicompost and metabolic activity testing are presented. Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5404]

Izolovanje mikroorganizama iz mednog i pravog želuca pčele, biohemijska i fiziloška karakterizacija mikroorganizama. Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5435]

Aim of this study is to separate aromatic fraction from diesel fuel and then to investigate the microbial biodegradation of aromatic fraction.

In our work we have studied the process of bioremediation of waste heavy residual oil fuel (mazut) from the site of the Belgrade heating plants. Bioremediation is performed on the projected biopile adding microbial consortium that was isolated from the pollutet site. We added nutrients (biostimulation) at biopile, and aeration is provided by periodic mixing. Biostimulation and inoculation of biopile for 150 days resulted in a decrease of total petroleum hydrocarbons (TPH) for about 80 times and increased content of humic acids that indicate the beginning of Soilification. This "primitive" soil was used as an overlay for the stabilization of municipal waste landfill after bioremediation. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5470]

Polysaccharides based on fructose, also called fructans, are synthetized from sucrose by some plant species and many bacteria, fungi and Archaea. Levan is an exopolysaccharide composed of fructose units and has numerous applications in personal care and cosmetics, medicine and food industry. Polystyrene is the most widespread polymer for plastic production due to its low costing and easy production. Degradation of polystyrene is longterm process, therefore incorporating natural polymers is the desirable approach. In the present study, levan-polystyrene graft copolymer (L-g-PS) was synthetized, characterized and influence of reaction time on grafting reaction at two temperatures was investigated. Levan was isolated after cultivation Bacillus licheniformis NS032. Syntheses of L-g-PS were performed by the free radical reaction using K2S2O8 as initiator. Grafting reactions proceeded in nitrogen atmosphere, at 55ºC and 70ºC and reaction time ranged between 15 and 210 min. FTIR spectra and XRD patterns were recorded using a Thermo Nicolet 6700 Spectrophotometer and Philips PW-1710 automated diffractometer, respectively. The formation of L-d-g-PS was confirmed by FTIR spectra which displayed the presence of all characteristic peaks for both component and X-ray diffractograms which showed amorphous nature of copolymer. Compared to other reaction parameters, the temperature of 70ºC and time of 45 min was more optimal showing higher percentage of grafting.

Chemical and biochemical activities of microorganisms are obvious in industrial biotechnology. They are becoming even more important in environmental biotechnology and circular economy. The application of microorganisms in remediation, environmental protection and management have proven that they are "biological agents" of choice. In bioremediation processes they may be used for the treatment of waste water as well as for polluted surface and underground waters, polluted soil and process gases, i.e. indirectly, even for polluted air. In situ and ex situ bioremediation procedures for the treatment of soil and underground water contaminated by oil derivatives with the application of zymogenous active microbial consortia on the industrial level have shown in our multi-year practice to be very effective and applicable in all aspects. During biodegradation of oil pollutants, the soilification of the substrate has occurred through the process of humification. Laboratory experiments dealing with the recovery of a number of elements from electronic waste (printed circuit boards) with the application of the bacterial species Acidithiobacillus ferrooxidans that generates/regenerates iron(III)-ion as an active reagent for the solution of metals have proven that biohydrometallurgical procedures have potential application in the recycling and reuse of technically important metals such as are rare earth elements-REE (critical materials). It may be concluded that microorganisms are undoubtfully the most useful "green" agents in the area of environmental protection and in the future, in circular economy of some of critical elements. Microorganisms are inseparable from the green chemistry and engineering and they are an important link in the sustainable development. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5488]

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 this study is to develop innovative granular multicomposite fertilizer based on vermicompost.

Lignin depolymerization could be an important technique for the production of valuable aromatic compounds. The aim of this work was to investigate the degradation of kraft lignin by a mixed culture of fungi and to identify degradation products using comprehensive two-dimensional gas chromatography-mass spectrometry (GCxGC-MS). Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5415]

Cilj ovog rada je bio izolovati i upotrebiti mikrobni levan za sintezu novog tipa kalemljenog kopolimera sa stirenom i ispitati uticaj aminoaktivatora na reakciju kalemljenja. The aim of this study was to isolate and use microbial levan for the synthesis of a new type of grafted copolymer with styrene and to investigate the influence of amino activators on the grafting reaction. Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5433]

Humic substances have an important role in soil fertility, plant three nutrition and the stabilization of soil aggregates. They are divided into three components: humin, humic acids and fulvic acids. In nature, lignocellulose accounts for the major part of biomass and its degradation is one of the main contributors to the formation of humic substances. It is composed of polysaccharides (hemicelluloses and cellulose) and aromatic polymer (lignin). White and brown rot fungi are well known for their essential role in naturally occurring degradation of lignocellulosic biomass, which is enabled by secretion of extracellular ligninolytic enzymes. Composting is an aerobic process during which different waste products are partly mineralized and partly converted to humic substances. It has been claimed that during composting, lignin is the major contributor to the biosynthesis of humic acids. One of the most abundant forms of lignin is Kraft lignin, a byproduct of the alkaline sulfide treatment of lignocelluloses in the paper mill industry. The aim of this work was to investigate the potential of mixed culture of fungi to degrade kraft lignin. Degradation process was monitored with respirometric test to assess the cot production and with comprehensive two-dimensional gas chromatography-mass spectrometry (GCxGC-MS), to identify the degradation products. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5334]

The aim of this work was structural characterization of EPS produced by Brachybacterium paraconglomeratum sp. CH-KOV3. For the structural instrumental analysis of EPS, the following methods were applied: GC-MS (gas chromatography mass spectrometry) and correlated two-dimensional NMR (nuclear magnetic resonance) techniques - DEPT 135 (distortionless enhancement by polarization transfer), COSY (correlation spectroscopy), and HSQC (heteronuclear single quantum coherence). Methylation was performed by the method which described earlier. The permethylated EPS was subjected to reductive cleavage as described by Rolf and Gray. Cleaved monomer units were acetylated. Obtained acetylated, methylated products were analyzed by GC-MS. These analyses were performed on a GCxGC-MS (Shimadzu, Kyoto, Japan). NMR spectra of the isolated EPS were measured on a Bruker AVANCE III 500 spectrometer.

The microorganisam Streptomyces hygroscopicus CH-7 produces antibiotics Hexaene, Nigericine and Elaiophyline. The yield of antibiotics can be increased by changing the fermentation conditions and the composition of the nutrient medium. Based on the previous research with this strain and the literature reviewed, the aim of this work was to study the possibility of using waste materials (whey with proteins in varying ammounts and crude glycerol from the biodiesel production) as a carbon and nitrogen source in order to increase the yeald of antibiotics produced by Streptomyces hygroscopicus CH-7. The maximum concentration of Hexaene (47,2 μg/ cm3) was achieved in the medium with whey containing 80% of protein and glycerol from sunflower oil, while the maximum concentration of Elaiophyline (24,3μg/cm3) was achived in the basal medium. Mikroorganizam Streptomyces hygroscopicus CH-7 produkuje antibiotike Heksaen, Nigericin i Elaiofilin. Promenom uslova fermentacije i sastava hranljive podloge može se povećati produkcija antibiotika. Na osnovu dosadašnjih istraživanja sa ovim sojem i literaturnog pregleda, cilj ovog rada je bio da se ispita mogućnost primene otpadnih sirovina (surutke sa različitim procentom proteina i sirovog glicerola iz proizvodnje biodizela) kao izvora ugljenika i azota, kako bi se povećala produkcija antibiotika pomoću Streptomyces hygroscopicus CH-7. Maksimalna koncentracija Heksaena (47,2 μg/cm 3) postignuta je na podlozi sa surutkom (koja sadrži 80% proteina) i glicerolom iz suncokretovog ulja, dok je maksimalna koncentracija Elaiofilina (24,3μg/cm3) ostvarena na osnovnoj podlozi.

This study was focused on investigating researching humification process during the ex situ experiment of bioremediation of soil contaminated with petroleum and its products from Rafinery Pančevo.

In this work, microbial polysaccharide levan from Bacillus licheniformis strain was firstly oxidized to polyaldehyde, then reduced to polyalcohol, completely hydrolyzed, and finally acetylated. Resulting peracetylated alcohols were characterized by GC-MS and compared to the results from corresponded acetylated standards.

Novel chromogenic macromolecular substrate was synthesized by covalently coupling of branched β-glucan isolated from the cell-wall of baker’s yeast S. cerevisiae with anthraquinone reactive dye Remazol Brilliant Blue R (RBBR). New material could potentially have many applications, i.e. for evaluation of endo- and exo-1,3/1,6 glucanases or for screening of β-glucan-degrading microorganisms.

The aim of this work was to investigate dibenzothiophene (DBT) biodegradation of products formed during ex situ bioremediation of a soil contaminated with heavy residual fuel oil. Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/5207]

The aim of this paper is to study the use of different microorganisms as “biological agents” through processe which are of crucial importance for soil formation. The processe includes the study of an active consortium of zymogenous microorganisms for ex situ bioremediation of a complex petroleum contaminant in soil substrate, along with simultaneous monitoring of the humification process.

The aim of this work was to conduct microbiological and biochemical characterization of Klebsiella variicola, bacterial strain isolated from an environment polluted PFOS.

The aim of this work is the isolation of levan from the Bacillus licheniformis strain and the synthesis of a new levan-polystyrene grafted copolymer. Cilj ovog rada je izolovanje levana iz soja Bacillus licheniformis i sinteza novog levan-polistiren graftovanog kopomlimera.

Solubleinulin pimaricin conjugate have been synthesized by coupling of aldehyde-functionalized polysaccharide inulin with a water-insoluble tetraene macrocyclic membrane-active antifungal antibiotic pimaricin. The synthesized product was soluble in water and characterized by UV-VIS and 1HNMR spectroscopic data.

Poster presented at SETAC Europe 26th Annual Meeting, Nantes, France, May 22-26, 2016 Abstract: [https://cer.ihtm.bg.ac.rs/handle/123456789/5288]