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Three-hydroxyl alcohol glicerol, obtained during the biodiesel production, can be observed as a crude glicerol fraction because of the impurity content. Current researches around the world are aimed at studying the possibilities of converting waste glicerol into various products. Glicerol can be used as the main source of carbon in media for industrial fermentations. This dissertation was studying the possibility of microbial utilization of waste glicerol, obtained as a by-product in the production of biodiesel from sunflower and rapeseed oil, using Enterococcus faecalis MK3-10A lactic acid bacteria, Streptomyces hygroscopicus CH-7 bacteria and freshwater microalgae. Bacteria E. faecalis MK3-10A did not produce a significant amount of lactic acid.The highest production of 14,64 mg/ml/d was achieved in medium containing waste glicerol obtained in biodiesel production from sunflower oil. Depending on the medium, consumption of glicerol was 21-37 %. Cultivating in media containing waste glicerol, as opposed to media with glucose, bacteria S. hygroscopicus CH-7 showed lower growth and did not produce significantly higher amounts of antibiotics. However, addition of isatin derivatives, as a nitrogen source, significantly increased the production of antibiotics. Isatin-3-hydrazone shows the best influence on the antibiotics production, wherein the maximum concentration of hexaene H-85 (196 μg/ml) and azalomycine B (75μg/ml) was obtained. An isolated strain of algae, characterized as a member of genus Chlorococcum, grows well and consume all of available quantity of clean and waste glicerol from sunflower oil, as well as significant amount of glicerol from rapeseed oil (61 %), but in comparison to other isolated strains of algae it produces the least amount of microbial oil (15-23 %). Regardless of weaker growth and consumption of glicerol, Chlorella and Scenedesmus strains produce the most microbial oil (27-35 %). The general conclusion of this thesis is that the waste gl

The objective of this study was to stimulate microbial biodegradation of petroleum pollution in groundwater and to analyze changes in the abundance and distribution of organic compounds detectable in petroleum. Bioremediation was conducted in a closed bipolar system, by bioaugmentation with consortia of hydrocarbon degrading microorganisms (HD) and biostimulation with nutrients. Comprehensive twodimensional gas chromatography-mass spectrometry (GC X GC-MS) was used to visualize all fractions simultaneously. During the study, the content of total petroleum hydrocarbon (TPH) in groundwater decreased by 92.7% of the initial level, and the average rate of biodegradation was 0.1 mg/L per day. Increased numbers of HD were observed and the dominant genera were Pseudomonas, Rhodococcus, Achromobacter, Bacillus, and Micromonospora. In the first 30 days of bioremediation, there was no significant biodegradation of n-alkanes and petroleum biomarkers - isoprenoids such as pristane and phytane, and polycyclic-saturated hydrocarbons such as terpanes and steranes. However, after 60 days of bioremediation, more than 95% of n-alkanes, terpanes and steranes were biodegraded. Phenanthrene and its methyl-,dimethyl-, and trimethyl-isomers were biodegraded and reduced by more than 99% of their initial levels. However, their decomposition had clearly commenced after just 30 days. This is a somewhat surprising result since it follows that the phenanthrenes were more susceptible to biodegradation than the n-alkanes and isoprenoids. Depending on the microbial community used for bioaugmentation, biodegradation of phenanthrene can precede biodegradation of saturated hydrocarbons.

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.

Various microorganisms isolated from polluted environments, such as Pseudomonas sp. and Micrococcus sp. can synthesize exopolysaccharides (EPSs) which are natural, non-toxic and biodegradable polymers. EPSs play a key role in protection of microbial cells under various external influences. For humans, these substances have potential use in many industries. EPSs can be applied as a flavor or a fragrance carrier, an emulsifier, a stabilizer, a prebiotic, an antioxidant or an antitumor agent. In this study, we characterized an environmental microorganism that produces EPS, optimized EPS production by this strain and characterized the EPS produced. Isolate CH-KOV3 was identified as Brachybacterium paraconglomeratum. The sucrose level in the growth medium greatly influenced EPS production, and the highest yield was when the microorganism was incubated in media with 500 g/L, of sucrose. The optimal temperature and pH were 28 degrees C and 7.0, respectively. The nuclear magnetic resonance (NMR) results and GC MS analysis confirmed that the residues were D-fructofuranosyl residues with beta-configuration, where fructose units are linked by beta-2,6-glycosidic bonds, with beta-2,1-linked branches. All these data indicate that the investigated EPS is a levan-type polysaccharide. Thus, it was concluded that Brachybacterium sp. CH-KOV3 could constitute a new source for production of the bioactive polysaccharide, levan.

Bioremediation is the process of detoxification or elimination of pollutants using microorganisms with different metabolic capabilities. Biodegradation by natural populations of microorganisms is one of the primary mechanisms by which oil and other pollutants of hydrocarbon origin can be removed from the environment and it is also much cheaper than the other remediation technologies. In this study, we analyzed the samples of historical waste from the oil industry, which contained sand, organic materials, heavy fuel oil and catalysts used during the process of hydrodesulfurization (HDS) of oil. The aim was to examine the fate of cobalt and molybdenum, toxic heavy metals present in those catalysts. A consortium of microorganisms isolated from the complex pollutants from the oil industry was added to the samples. During the study, beside the transformation of cobalt and molybdenum forms, we also monitored the biodegradation process of the total petroleum hydrocarbons (TPH).

Nutrition is one of the most important environmental factors that influence the development and growth in Drosophila. The food composition strongly affects their reproduction, welfare and survival, so it is necessary for flies to search for a mixture of macronutrients that maximizes their fitness. We have five D. melanogaster strains, which were reared for 13 years on five different substrates: standard cornmeal-agar-sugar-yeast medium and four substrates modified by adding tomato, banana, carrot and apple. This study was aimed at determining how such long-term rearing of flies on substrates with different protein content affects fitness traits (dynamics of eclosion, developmental time and egg-to-adult survival). Further, we determined how transferring flies reared on fruit/vegetable substrates to a standard laboratory diet affected their fitness. Results indicate that strains reared on the diet with the lowest content of protein and the highest C/N ratio had the slowest eclosion and developmental time, and lowest egg-to-adult survival (apple diet). The flies reared on the diet with the highest protein content and the lowest C/N ratio had the highest survival (tomato diet). Flies reared on the carrot diet, which is quite similar in protein content and C/N ratio to the standard cornmeal diet, had the fastest development. Transferring flies to the standard cornmeal diet accelerate eclosion and developmental time, but did not affect survival.

Oil industry is the largest or potentially the largest source of pollutants for all ecospheres. This applies to all segments, from exploitation to processing, transportation, storage and use of fuel and raw materials for petrochemical industry.

In the present work, four derivatives of salicylaldehyde (salicylaldehyde-hydrazone, phenylhydrazone, semicarbazone and thiosemicarbazone) were synthesized using both conventional (95% ethanol) and green (crude glycerol from biodiesel production) solvents. The obtained compounds were identified by elemental microanalysis, as well as FTIR, UV/Vis and H-1-NMR spectroscopic methods. Yields of 93-98% of the compounds in crude glycerol were achieved within 10-25 min. The derivatives of salicylaldehyde and crude glycerol were used as a nitrogen and carbon source, respectively, in the medium for antibiotic (hexaene H-85 and azalomycine B) production by Streptomyces hygroscopicus CH-7. The highest concentrations of hexaene H-85 and azalomycine B were achieved in the medium containing salicylaldehyde-thiosemicarbazone (198 and 69 mu g/cm(3), respectively). Derivatives of salicylaldehyde also impacted the strain morphology. In the media with salicylaldehyde- phenylhydrazone and salicylaldehyde-thiosemicarbazone, S. hygroscopicus CH-7 grew like large dispersive pellets with long twisted filaments that produced the highest yield of the antibiotics.

Bioremediation is the process of detoxification or elimination of pollutants using microorganisms with different metabolic capabilities. Biodegradation by natural populations of microorganisms is one of the primary mechanisms by which oil and other pollutants of hydrocarbon origin can be removed from the environment and it is also much cheaper than the other remediation technologies. In this study, we analyzed the samples of historical waste from the oil industry, which contained sand, organic materials, heavy fuel oil and catalysts used during the process of hydrodesulfurization (HDS) of oil. The aim was to examine the fate of cobalt and molybdenum, toxic heavy metals present in those catalysts. A consortium of microorganisms isolated from the complex pollutants from the oil industry was added to the samples. During the study, beside the transformation of cobalt and molybdenum forms, we also monitored the biodegradation process of the total petroleum hydrocarbons (TPH).

Izolovanje mikroorganizama iz mednog i pravog želuca pčele, biohemijska i fiziloška karakterizacija mikroorganizama.

Microbial fatty acid analysis represents a simple and rapid method for identification of strains mainly for taxonomic purpose. Fatty acid composition in the whole cells and lipopolysaccharides in Rhizobiaceae were studied to point at biochemical events of the nitrogen-fixing symbiosis too. In this study the fatty acid profiles of six strains Bradyrhizobium japonicum and three strains Sinorhizobium meliloti were analyzed. The strains were isolated from soils of Serbia and obtained from collection of Institute of Soil Science. Methyl esters of total fatty acids were prepared from lyophilised biomass using toluene-methanol-sulphuric acid mixture and analyzed using GC-MS method. In Sinorhizobium meliloti strains the main components are 16:0, 218:1. cy-19:0 and in lesser proportion are cy 17:0. 17:0. 18:0. 16:1, 3-OH 14:0, 15:0 and 14:0 fatty acids. The results obtained are in accordance with previously reported data. The absence of 20:3(0 6,9,12cis and 3-OH 16:0 fatty acids in all chromatograms might be explained by differences in derivation method or growth medium used. The ineffective strain (Nod+Fix-) contains remarkable less cyl7:0 acid. Dominant components in Bradyrhizobium japonicum strains are 118:1 and 16:0 fatty acids. Also cy19:0, 18:0 and 16:1 components were detected and certain shifts in the amount of these minor components observed. However, on the basis of our results there is no correlation between the relative content of particular fatty acid and the fixing effectiveness of tested strain., Analiza masnih kiselina mikroorganizama, jednostavna i brza metoda za identifikaciju sojeva, često se koristi u taksonomiji. Masne kiseline celih ćelija i lipopolisaharida kod Rhizobiaccae su od posebnog značaja za proučavanje simbiotske azot o fiksacije. U ovom radu su analizirani profili masnih kiselina šest sojeva Bradvrhizobium japonicum i tri soja Sinorhizobium meliloti. Sojevi su ili izolovani iz uzoraka zemlje rz Srbije ili potiču iz kolekcije Instituta za zemljište. Metil estri ukupnih masnih kiselina su pripremani digestijom liofilizovane biomase u smesi toluol-metanol-sumporna kiselina i analizirani GC-MS metodom. Kod sojeva Sinorhizobium meliloti glavne komponente su 16:0, Z18; l, cj'19:0 i u manjem procentu cy 17:0, 17:0, 18:0, 16:1, 3-OH 14:0, 15:0 i 14:0 masne kiseline. Dobijeni rezultati su u saglasnosti sa literaturnim podacima, a odsustvo 20:3co 6,9.12r/s i 3-OH 16:0 masnih kiselina u svim hromatogramima se može objasniti razlikama u sastavu podloge korišćene za gajenje i načinu pripreme metil estara. Neefektivni soj (Nod+Fix-) sadrži znatno manje cy 17:0 kiseline. Dominantne komponente kod sojeva Bradyrhizobium japonicum su Z18: l i 16:0 masne kiseline. Pored toga detektovane su i cy 19:0, 18:0 and 16:1 masne kiseline. Uočene razlike u koncentraciji ovih minornih komponenata su verovatno posledica različite brzine rasta, pa na osnovu dobijenih rezultata nema korelacije između sadržaja masnih kiselina i efektivnosti azotofiksacije kod ispitivanih sojeva.

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.

The field of microbial polysaccharides is an immensely developing field over the last two decades as a result of its wide-ranging applications in different areas of science and technology. Microbial exopolysaccharides (MPSs) such as xanthan, dextran, gellan, pullulan and levan have been commercially used in their natural or modified state for many years. A large number of these natural polymer applications is a consequence of their excellent physical and chemical properties, based on their capacity to alter the basic properties of water (e.g. thickening or gelling). In addition, these polymers have secondary functions, such as emulsification, suspension, stabilization, encapsulation, flocculation, film forming, binding and coating. MPSs, and particularly exopolysaccharides, have many other novel properties to offer, and the discovery of immune modulation and bifidogenic effect of some of them should provide other applications. This work focuses on the more recent developments in the extent of application of microbial polysaccharides in the various fields which makes these polymers promising and versatile materials in the future, and also in our investigations of these natural products.

The group of polycyclic aromatic hydrocarbons (PAHs) are very hazardous environmental pollutants because of their mutagenic, carcinogenic and toxic effects on living systems. The aim of this study was to examine and compare the ability and efficiency of selected bacterial isolates obtained from oil-con-taminated areas to biodegrade PAHs. The potential of the bacteria to biodeg-rade various aromatic hydrocarbons was assessed using the 2,6-dichlorophe-nolindophenol assay. Further biodegradation of PAHs was monitored by gra-vimetric and gas-chromatographic analysis. Among the eight bacterial isolates, identified on the basis of 16S rDNA sequences, two isolates, Planomicrobium sp. RNP01 and Rhodococcus sp. RNP05, had the ability to grow on and utilize almost all examined hydrocarbons. Those isolates were further examined for biodegradation of phenanthrene and pyrene, as single substrates, and as a mixture, in vitro for ten days. After three days, both isolates degraded a significant amount phenanthrene, which has a simpler chemical structure than pyrene. Planomicrobium sp. RNP01 commenced biodegradation of pyrene in the PAH mixture only after it had almost completely degraded phenanthrene. The isolated and characterized bacteria, Planomicrobium sp. RNP01 and Rhodococcus sp. RNP05, have shown high bioremediation potential and are likely candidates to be used for degradation of highly toxic PAHs in contaminated areas.

The effect of isatin derivatives as a nitrogen source on antibiotic (hexaene H-85 and azalomycine B) production by Streptomyces hygroscopicus CH-7 was studied. Isatin-3-hydrazone, 5-chloroisatin-3-hydrazone, isatin-3-tosylhydrazone, 5-chloroisatin-3-tosylhydrazone, isatin-3-(4-hidroxy) benzoilhydrazone and 5-chloroisatin-3-(4'-hidroxy) benzoylhydrazone were synthesized in a crude glycerol, obtained during the biodiesel production from edible sunflower oil. The highest concentration of Hexaene H-85 is achieved with 5-chloroisatin-3-hydrazone (197 mu g/cm(3)) in medium, while isatin-3-hydrazone has the greatest impact on azalomycine B production (72 mu g/cm(3)).

The aim of our study was to analyze the PCBs biodegradation potential of autochthonous and allochthonous microorganisms in river sediment samples in order to protect the environment and estimate future treatment of these sites. This samples collected from rivers in the territory of Belgrade, Serbia, from four locations.

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

Novel macromolecular graft copolymers were synthesized by reaction of the hydroxyl groups of the microbial polysaccharide levan, produced using Bacillus licheniformis, with polystyrene (Lev-g-PS). Synthesis was performed by the free radical reaction using potassium persulfate (PPS) as initiator. The prepared copolymer was characterized by FTIR, SEM, TG/DTA, XRD and C-13 NMR. The influence of the different conditions (reaction temperature, air or nitrogen atmosphere, reaction time, type of amines and ascorbic acid (AA) concentration) on the grafting reaction was investigated. Results showed that maximum percentage of grafting (58.1%) was achieved at a reaction temperature 70 degrees C, in a nitrogen atmosphere and using dimethylethanolamine (DMEA) as the amine activator. On the basis of the obtained results, the likely reaction mechanism was proposed. Synthesized copolymers have better thermal stability in comparison with their initial components. Copolymers such as Lev-g-PS could potentially have many applications, such as compatibilizers and material for membranes.

Iron and sulfur oxidizing chemolithoautotrophic acidophilic bacteria, such as Acidithiobacillus species, hold the dominant role in mine environments characterized by low pH values and high concentrations of reduced sulfur and iron compounds, such as ores, rocks and acid drainage waters from mines. On the other hand, heterotrophic microorganisms, especially their biofilms, from these specific niches are receiving increased attention, but their potential eco-physiological roles have not been fully understood. Biofilms are considered a threat to human health, but biofilms also have beneficial properties as they are deployed in waste recycling and bioremediation systems. We have analyzed interactions of the metal tolerant heterotrophic microorganisms in biofilms with iron oxidizing autotrophic bacteria both from the sulphidic mine environment (copper mine Bor, Serbia). High tolerance to Cu2+, Cd2+ and Cr6+ and the presence of genetic determinants for the respective metal tolerance and biofilm-forming ability was shown for indigenous heterotrophic bacteria that included strains of Staphylococcus and Rhodococcus. Two well characterized bacteria-Pseudomonas aeruginosa PAO1 (known biofilm former) and Cupriavidus metallidurans CH34 (known metal resistant representative) were also included in the study. The interaction and survivability of autotrophic iron oxidizing Acidithiobacillus bacteria and biofilms of heterotrophic bacteria during co-cultivation was revealed. Finally, the effect of heterotrophic biofilms on bioleaching process with indigenous iron oxidizing Acidithiobacillus species was shown not to be inhibitory under in vitro conditions.

Aim of this study was to compare oxidative stress induced by copper(II) in Daphnia magna in the presence and absence of levan.