THE EFFECT OF DEMULSIFIER AND DEWATERING AGENT ON SEPARATION OF PHASES FROM OILY WATER

Environmental pollution with crude oil and its derivates has become a growing problem due to their toxic and carcinogenic effects on live organisms. Proper collection and treatment of oily wastewaters is very important for prevention and disabling of harmful effects on the environment. The most important step in the oily wastewater treatment process is separation of oil and aqueous phase. Consequently, it is important to examine the conditions which enable the maximum separation effect and provide satisfactory quality of the aqueous phase before discharge into natural recipients. This paper examines the effects of temperature and addition of demulsifier and dewatering agent on phase separation in oily wastewaters. The best separation rate and the highest quantity of the aqueous phase are achieved with the addition of demulsifier in concentration of 500 mg/l and the dewatering agent in concentration of 500 mg/l at 60 °C. The quality of the aqueous phase after separation shows low values of mineral oils and high COD (Chemical Oxygen Demand) values due to the remaining demulsifier and dewatering agent in aqueous phase. For that reason it is necessary to use additional treatments, such as adsorption on active carbon or biological treatment before discharge into natural waters

Trametes suaveolens as ligninolytic enzyme producer

Species of the genus Trametes represent one of the most efficient lignin-degraders which can be attributed to a well developed ligninolytic enzyme system. Current trends are screening of ability of new species to produce these enzymes, as well as the optimization of conditions for their overproduction. Therefore, the aim of the study was to evaluate the potential of T. suaveolens to synthesize laccase and Mn-oxidizing peroxidases during fermentation of the selected plant raw materials. Level of enzyme activities was measured on 7, 10 and 14th day of submersion, as well as the solid-state fermentation of wheat straw and oak sawdust in the presence of NH4NO3 in previously determined optimal nitrogen concentration of 25 mM. The enzyme activity was determined spectrophotometrically using ABTS and phenol red as the substrates. The highest level of laccase activity (1087.1 U/L) was noted after 7 days of wheat straw solid-state fermentation, while during the submerged cultivation the production of the enzyme was not noted. Submerged cultivation in oak sawdust-enriched medium was the optimal for activity of Mn-dependent peroxidase (1767.7 U/L on day 14) and Mn-independent peroxidase (1113.7 U/L on day 7). Introduction of T. suaveolens to produce ligninolytic enzyme represented the base for further study, as well as the determination of relation between enzyme activity and rate of lignin degradation. It could lead to greater possibility of fungal species selection with high delignification capacity, which could take participation in sustainable production of food, feed, fibres, and energy, environmentally friendly pollution prevention, and bioremediation

Biofilm forming cyanobacteria, algae and fungi on two historic monuments in Belgrade, Serbia

Biofilm on the sandstone substrata of the bridge 'Brankov most' and on the granite substrata of the 'Monument of the Unknown Hero' contains a complex consortia of cyanobacteria, algae, and fungi. Coccoid and filamentous cyanobacteria, green algae and diatoms make up the photosynthetic part of the biofilm while hyphal fragments, chlamydospores, fruiting bodies and spores take part as fungal components. These structures make a dense layer by intertwining and overlapping the stone surface. Five cyanobacterial, 11 algal and 23 fungal taxa were found. The interaction of the biofilm's constituents results in the bioweathering of the stone substrata through mechanical penetration, acid corrosion and the production of secondary mycogenic biominerals.

Variability of Phomopsis populations in sunflower (Helianthus annuus L.)

Various reports state that the sunflower disease, primarily caused by Diaporthe/Phomopsis helianthi Munt.-Cvet. et al., has a wide geographic distribution in Europe, USA, Argentina and Australia. Various Phomopsis isolates obtained during this investigation of the sunflower disease differed in conidial type (α, β, α and β). Phomopsis helianthi was the only isolate producing exclusively β-conidia and perithecia on debris (Diaporthe helianthi). The other Phomopsis isolates were saprobes on sunflower plants.nul

In vitro antifungal and demelanizing activity of Nepeta rtanjensis essential oil against the human pathogen Bipolaris spicifera

The antifungal activity of Nepeta rtanjensis Diklić & Milojević essential oil was tested against the human pathogenic fungus Bipolaris spicifera (Bainier) Subramanian via mycelial growth assay and conidia germination assay. The minimally inhibitory concentration (MIC) of the oil was determined at 1.0 μg ml-1, while the MIC for the antifungal drug Bifonazole in a positive control was determined at 10.0 μg ml-1. The maximum of conidia germination inhibition was accomplished at 0.6 μg ml-1. In addition, at 0.6 μg ml-1 and 0.8 μg ml-1 the oil was able to cause morphophysiological changes in B. spicifera. The most significant result is the bleaching effect of the melanized conidial apparatus of the test fungi, since the melanin is the virulence factor in human pathogenic fungi. These results showed the strong antifungal properties of N. rtanjensis essential oil, supporting its possible rational use as an alternative source of new antifungal compounds

Polne populacije kompleksne vrste Gibberella fujikuroi (Sawada) S. Ito poreklom iz kukuruza, gajenog sirka i pšenice u Srbiji

The status of fertility and distribution of mating populations in the G. fujikuroi species complex, isolating from maize, sorghum and wheat cultivated under various agroecological conditions of Serbia, have been studied. A total of 79 field isolates of Fusarium spp. in the section Liseola, which had been reciprocally crossed to standard testers (MAT-1 and MAT-2) from each of the four mating populations of the G. fujikuroi species complex, were selected for these studies. Twenty of 79 isolates belonged to the mating population A (G. moniliformis), 22 to the population D (G. intermedia), 17 to the population E (G. subglutinans) and 20 to the population F (G. thapsina). A mating type MAT-1 was dominant in the populations A (14 MATA-1 :6 MATA-2), D (13 MATA-1 :9 MATA-2) and E (10 MATA-1 :7 MATA-2), while MAT-2 prevailed in the population F (6 MATA-1 : 14 MATA-2). The obtained results indicate that the possibility of sexual reproduction of Fusarium spp., belonging to the A, D, E and F mating populations, is not so frequent phenomenon in Serbia as in other regions world-wide. Consequently, these species will be asexually reproduced under field conditions, particularly species belonging to the F population. These are the first results on the characterisation of three (A, E and F) out of four populations of the G. fujikuroi species complex present in Serbia.U radu su proučavani fertilnost i distribucija polnih populacija i tipova u okviru kompleksne vrste G. fujikuroi, poreklom iz različitih biljnih vrsta (kukuruza, gajenog sirka i pšenice), koje su gajene u različitim godinama i agroekološkim uslovima Srbije. Za proučavanja su odabrana 79 poljskih izolata Fusarium spp. iz sekcije Liseola, koji su recipročno ukršteni sa standardnim testerima (MAT-1 i MAT-2) od četiri polne populacije kompleksne vrste G. fujikuroi. U ukrštanjima je fertilno potomstvo dalo 77 od 79 izolata. Od 77 izolata 20 je pripadalo polnoj populaciji A (G. moniliformis), 22 populaciji D (G. intermedia), 15 populaciji E (G. subglutinans) i 20 populaciji F (G. thapsina). Polni tip MAT-1 je dominirao u populacijama A (14 MATA-1 :6 MATA-2), D (13 MATA-1 :9 MATA-2) iE(10 MATA-1 :7 MATA-2), dok je MAT-2 dominirao u populaciji F (6 MATA-1 : 14 MATA-2). Proučavani izolati su bili fertilni kao očevi a sterilni kao majke, izuzev po jedan izolat u populacijama A, D i E koji su bili hermafroditi. Na osnovu polnog tipa (Ne(mt)) efektivni broj za A i F populacije bio je 84.00%, za D je 96.69% i E je 96.89%. Na osnovu učestalosti hermafrodita efektivan broj (Ne(f)) za populaciju A bio je 18.15%, populaciju D 16.60%, populaciju E 20.84% i populaciju F 0.00% od stvarnog broja. Dobijeni rezultati ukazuju da je mogućnost seksualne reprodukcije Fusarium spp., koje pripadaju utvrđenim polnim populacija, nije učestala pojava u Srbiji, kao što je za njih utvrđeno u drugim regionima sveta. Kao posledica toga, ove vrste će se aseksualno reprodukovati u poljskim uslovima, posebno vrsta koja pripada F populaciji. Ovo su prvi rezultati o karakterizaciji tri (A, E i F) od četiri populacije kompleksne vrste G. fujikuroi, koje su prisutne u Srbiji

Supplementary material for the article: Stefanović, V.; Trifković, J.; Djurdjić, S.; Vukojević, V.; Tešić, Ž.; Mutić, J. Study of Silver, Selenium and Arsenic Concentration in Wild Edible Mushroom Macrolepiota Procera, Health Benefit and Risk. Environmental Science and Pollution Research 2016, 23 (21), 22084–22098. https://doi.org/10.1007/s11356-016-7450-2

Supplementary material for: [https://doi.org/10.1007/s11356-016-7450-2]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2348

Fungicide sensitivity of selected Verticillium fungicola isolates from Agaricus bisporus farms

Five isolates of Verticillium fungicola, isolated from diseased fruiting bodies of Agaricus bisporus collected from mushroom farms in Serbia during 2002-2003, were studied. By observing their colony morphology under different growth conditions and their pathogenic characteristics, the isolates were identified as V. fungicola var. fungicola. The peat/lime casing was the primary source of infection. Testing of sensitivity to selected fungicides showed that all isolates were highly resistant to benomyl (EC50 values were higher than 200.00 mg/l), moderately sensitive to iprodione (EC50 values were between 11.93 and 22.80 mg/l), and highly sensitive to prochloraz-Mn (EC50 values were less than 3.00 mg/l)

Potential of selected fungal species to degrade wheat straw, the most abundant plant raw material in Europe

Background: Structural component of plant biomass, lignocellulose, is the most abundant renewable resource in nature. Lignin is the most recalcitrant natural aromatic polymer and its degradation presents great challenge. Nowadays, the special attention is given to biological delignification, the process where white-rot fungi take the crucial place owing to strong ligninolytic enzyme system. However, fungal species, even strains, differ in potential to produce high active ligninolytic enzymes and consequently to delignify plant biomass. Therefore, the goals of the study were characterization of Mn-oxidizing peroxidases and laccases of numerous mushrooms as well as determination of their potential to delignify wheat straw, the plant raw material that, according to annual yield, takes the first place in Europe and the second one in the world. Results: During wheat straw fermentation, Lentinus edodes HAI 858 produced the most active Mn-dependent and Mn-independent peroxidases (1443.2 U L-1 and 1045.5 U L-1, respectively), while Pleurotus eryngii HAI 711 was the best laccase producer (7804.3 U L-1). Visualized bends on zymogram confirmed these activities and demonstrated that laccases were the dominant ligninolytic enzymes in the studied species. Ganoderma lucidum BEOFB 435 showed considerable ability to degrade lignin (58.5%) and especially hemicellulose (74.8%), while the cellulose remained almost intact (0.7%). Remarkable selectivity in lignocellulose degradation was also noted in Pleurotus pulmonarius HAI 573 where degraded amounts of lignin, hemicellulose and cellulose were in ratio of 50.4%:15.3%:3.8%. Conclusions: According to the presented results, it can be concluded that white-rot fungi, due to ligninolytic enzymes features and degradation potential, could be important participants in various biotechnological processes including biotransformation of lignocellulose residues/wastes in food, feed, paper and biofuels. © 2017 The Author(s)

Supplementary data for article: Đurđić, S. Z.; Sredojević, M.; Trifković, J.; Vukojević, V.; Natić, M.; Tešić, Ž. L.; Mutić, J. Elemental Composition as a Tool for the Assessment of Type, Seasonal Variability, and Geographical Origin of Wine and Its Contribution to Daily Elemental Intake. RSC Advances 2017, 7 (4), 2151–2162. https://doi.org/10.1039/c6ra25105f

Supplementary material for: [https://doi.org/10.1039/c6ra25105f]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2397