Dinamika brojnosti algi u ritskoj crnici u različitim ekosistemima

The aim of this research was to examine the dynamics of algae number in humogley in three different ecosystems (wood, meadows and arable land). The soil was sampled during four weather seasons throughout the year 2000 and samples were taken from three different depths: 0-1, 1-20 and 20-40cm. Number of algae depend on ecosystem type, soil depth and whether season. Among all the examined sites the highest number of algae was found in wood locality, afterwards in meadow site and arable land has shown to have the lowest number of algae. All the examined ecosystems have highest number of algae is in surface layers (0-1 cm) which decreases with depth, and is less present in arable soils comparing to non-arable soils.U radu je određena brojnost algi u tri različita ekosistema na ritskoj crnici (livada, šuma i njiva) u području makiškog rita, u toku 2000. godine. Uzorci su uzimani iz tri dubine zemljišnog profila: 0-1, 1-20 i 20-40 cm. Brojnost algi zavisi od tipa ekosistema, dubine zemljišnog profila i godišnjeg doba, kao i interakcije ovih faktora. U ekosistemima u kojima zemljište nije obrađivano konstatovana je statistički značajna razlika u odnosu na obrađeno zemljište. Najveća brojnost algi konstatovana je u šumskom ekosistemu a najmanja u oranici. Ukupan broj algi je najveći u površinskom sloju i sa dubinom zemljišnog profila opada. Opadanje brojnosti po dubini je veće u neobrađenim u odnosu na obrađeni ekosistem

Rast Pseudomonas CY u prisustvu benzena

The objective of this research is investigation of Pseudomonas CY growth, isolated from kerosene, in the presence of benzene. Thanks to their high enzymatic activity, microorganisms can use different compounds as a sole sources of carbon and energy, or they can use them in cometabolic processes. Their growth was observed by spectrophotometry measuring optical density on 500nm, while Pseudomonas count was determined on TSA. The growth was observed during specific time period (i.e. in following order: 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12 and 24h). There were used three concentrations of benzene. The results have shown that Pseudomonas population depended on benzene concentration and time. In the presence of benzene the bacterial growth was low, but after 24 hours the Pseudomonas count increased. These results indicate the possibility for Pseudomonas CY growth in the presence of benzene, but also the extension of adaptation phase comparing to normal growth curve. Therefore, the results show that using Pseudomonas population is a very feasible way for decreasing contamination level of soils and waters caused by certain organic compounds.Cilj ovog rada je ispitivanje rasta Pseudomonas CY, izolovanog iz kerozina, u prisustvu različitih koncentracija benzena. Mikroorganizmi zahvaljujući svojoj velikoj enzimskoj aktivnosti mogu koristiti različita organska jedinjenja kao jedinstvene izvore ugljenika i energije ili ih koristiti u toku procesa kometabolizma. Rast je praćen metodom spektrofotometrije merenjem optičke gustine na 560 nm a brojnost Pseudomonas bakterija je određena na TSA. Rast je praćen od nultog vremena do 24 sata (l, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12 i 24 h). U radu su korišćene tri koncentracije benzena. Rezultati pokazuju da je brojnost Pseudomonas populacije zavisila od koncentracije benzena ali i vremena. Rast bakterijskih populacija u prisustvu benzena je slabiji, ali nakon 24 sata brojnost se povećava. Ovi rezultati ukazuju da Pseudomonas CY može da raste u prisustvu benzena ali da je faza adaptacije produžena u odnosu na normalnu krivu rasta. Dobijeni rezultati ukazuju na mogućnost korišćenja Pseudomonas populacije za smanjenje stepena kontaminacije zemljišta i voda nekim organskim jedinjenjima

Filamentous fungi isolated from grape marc as antagonists of botrytis cinerea

In this paper we report on the isolation and identification of three filamentous fungi from grape marc, and antifungal effect of their cell-free culture filtrates on the growth of Botrytis cinerea, causal agent of gray mold. Grape marc is a waste material that has been used as soil amendment in sustainable agriculture. Isolates originating from grape marc were identified on the basis of morphological features and internal transcribed spacer rDNA or beta-tubulin gene sequencing. The presence of three different species, Penicillium paneum, Penicillium chrysogenum and Aspergillus fumigatus has been detected expressing different effect on the growth of B. cinerea. The effect of crude culture filtrates of selected fungi on B. cinerea growth was tested. Heat sensitivity of the established inhibition effect was examined by autoclaving the crude culture filtrate prior to testing. Additional aim was to determine whether antifungal effect was influenced by previous exposure to B. cinerea in dual liquid cultures. Crude culture filtrate of A. fumigatus K16/2 showed the lowest suppression of B. cinerea growth. A maximal percentage inhibition achieved within the study was 38.2%, 39.8% and 23.8 for crude filtrates of P. paneum K7/1, P. chrysogenum K11/1 and A. fumigatus K16/2, respectively. Presence of B. cinerea in dual liquid culture induced significant increase in antifungal capacity of the culture filtrates in comparison to pure culture filtrates of the chosen isolates. The antifungal activity of all of the isolates' culture filtrates retained after heat treatment suggesting the presence of some thermostable antifungal metabolites. The results indicate the complexity and specificity of the interaction between filamentous fungi and B. cinerea. Grape marc is a good source for isolation od B. cinerea fungal antagonists and their antifungal metabolites. Specificity of fungal-fungal interactions suggests that further research on the antagonistic mechanisms and factors affecting them should be studied separately for each pair of antagonists

Potential and Constraints of Macrophyte Manipulation for Shallow Lake Management

Palic and Ludas lakes are shallow Pannonian lakes, which have undergone rapid eutrophication. High concentrations of nutrients, along with significantly high values of fecal indicators in water samples, indicate that the Palic-Ludas canal, which connects them, contributes to the pollution of the recipient Lake Ludas, a central part of a special nature reserve. In order to improve water quality in the canal and decrease nutrient load of Lake Ludas, it is suggested to use environmentally friendly solutions, so-called bio-barriers (bio-bridges and biobanks), which will contribute to self-purification efficiency. The given model assumes 10 zones with bio-bridges and 0.4 ha covered by biobanks, using plants common in the area, e.g. Typha spp., Phragmites spp., Juncus spp., Scirpus spp. and Carex spp. The main disadvantage of this technology is occupation of large area; thus, the solution seems to be undersized. It removes 4% TN/year and 8% TP/year of the total amount necessary to achieve good ecological status. Nevertheless, the role of bio-bridges in permanent nutrient removal, through preventing the deposition of organic matter at the bottom sediment and later return of nutrients in water, together with indirect influence through enhancement of biodiversity should not be underestimated

Izolacija i karakterizacija bakterija i kvasaca iz kontaminiranog zemljišta

Plant growth promoting (PGP) bacteria and yeasts play an important role in bioremediation processes. Thirty bacterial and ten yeast isolates were obtained from PAH and PCB contaminated soil with an aim of determining the presence of PGP mechanisms (production of ammonia, indoleacetic acid, siderophores and solubilization of inorganic phosphate). As a result, three bacterial (Serratia liquefaciens, Micrococcus sp. and Serratia sp.) and two yeast isolates (Candida utilis and Candida tropicalis) were recognized as PGP strains. Among them, Serratia sp. showed the highest indole production (25.5 μg/ml). Analyses of metal tolerance (Cu+2, Cr+6 and Ni+2) revealed that Serratia liquefaciens, Micrococcus sp., Serratia sp. and Candida tropicalis were capable to tolerate significant concentration of metals. As a result of this study several bacterial and yeast strains were attributed as potential plant growth promoters which can be applied in future remediation activities and environmental quality improvements.Zemljište predstavlja dinamičan ekosistem naseljen brojnim mikroorganizmima među kojima su bakterije najbrojnije. Najveći broj je skoncentrisan u uskoj zoni zemljišta koja okružuje koren i koja se naziva rizosfera. Procenjuje se da 1-2% bakterija koje naseljavaju ovu zonu imaju sposobnost da promovišu rast biljaka (engl. plant growth promoting bacteria - PGPB). Pored bakterija, sve više je podataka da i zemljišni kvasci poseduju ove sposobnosti. Mikroorganizmi koji stimulišu rast biljaka koriste različite mehanizme kojima povećavaju dostupnost nutrijenata biljkama, regulišu njihov hormonski status kao i odnos prema biljnim patogenima. Bakterije i kvasci koji stimulišu rast biljaka igraju važnu ulogu i u procesima bioremedijacije. Trideset bakterijskih i deset izolata kvasaca je izolovano iz kontaminiranog zemljišta (PAH i PCB) i testirano na prisustvo mehanizama kojima se pospešuje rast biljaka. Cilj je bio doći do sojeva koji su prilagođeni na život u zagađenom zemljištu, a istovremeno imaju i potencijalno stimulativno dejstvo. Nakon izvršenih biohemijskih analiza (produkcija amonijaka, indol-sirćetne kiseline, siderofora, rastvaranje neorganskog fosfora) u stimulatore biljnog rasta svrstana su tri bakterijska (Serratia liquefaciens, Micrococcus sp. i Serratia sp.) i dva izolata kvasaca (Candida utilis i Candida tropicalis). Među njima najveću sposobnost produkcije indol-sirćetne kiseline je pokazao izolat Serratia sp. (25,5 μg/ml). Analize tolerancije na prisustvo teških metala (Cu+2, Cr+6 i Ni+2) pokazale su da su izolati Serratia liquefaciens, Micrococcus sp., Serratia sp. i Candida tropicalis sposobni da podnesu više koncentracije. Rezultati ovih istraživanja mogu imati praktičnu primenu u budućim remedijacionim aktivnostima i unapređenju kvaliteta životne sredine

Biodegradation of methyl tert-butyl ether by Kocuria sp.

Methyl tert-butyl ether (MTBE) has been used to replace the toxic compounds from gasoline and to reduce emission of air pollutants. Due to its intensive use, MTBE has become one of the most important environment pollutants. The aim of this paper is isolation and identification of the bacteria from wastewater sample of “HIP Petrohemija” Pančevo (Serbia), capable of MTBE biodegradation. The results of the investigation showed that only the bacterial isolate 27/1 was capable of growth on MTBE. The result of sequence analyzes of 16S rDNA showed that this bacterial isolate belongs to the Kocuria sp. After the incubation period of 86 days, the degradation rates of initial MTBE concentration of 25 and 125 μg/ml were 55 and 36%, respectively. These results indicated that bacteria Kocuria sp. is successfully adapted on MTBE and can be potentially used in bioremediation of soils and waters contaminated with MTBE

Mikrobni diverzitet zemljišta kontaminiranog visokim sadržajem teških metala

Except of benefits for human population, several industrial activities have a negative consequences i.e. increasing of heavy metal content and changes in diversity of living organisms in environment. The aim of this work was to examinated the influence of high content of heavy metals on microbial diversity of soil. Researches was conducted at locations of former factory 'Rog' (Ljubljana, Republic of Slovenia), by taking of four samples of contaminated soil, while the control was uncontaminated soil sample. Determination of microbial diversity (abundance of bacteria, fungi and actinomycetes) was performed using the standard methodology. The results of research showed that abundance of microorganisms depends on location and presence/absence of contamination. In control treatment abundance of all examinated groups of microorganisms was higher compared with other samples. The bacterial number in contaminated samples was from 1.21 to 6.88x106 CFU/g, the number of fungi was from 1,08 to 30,30x103 CFU/g, while actinomycetes number from 302,15 to 381,82x103 CFU/g. In control treatment, bacterial number was 17,45x106 CFU/g, fungi number 54,02x103 CFU/g and actinomycetes number 481,91x103 CFU/g. These results confirms the importance of microbial diversity research on contaminated locations and potential applications of bioremediation technologies on locations of former factory 'Rog'.Mnogobrojne industrijske aktivnosti, osim koristi za ljudsku populaciju, imale su za posledicu povećanje sadržaja teških metala i promene diverziteta živih organizama u životnoj sredini. Cilj ovog rada bio je ispitivanje uticaja visokih koncentracija teških metala na mikrobni diverzitet zemljišta. Istraživanja su obavljena na području bivše fabrike 'Rog' (Ljubljana, Republika Slovenija), gde su uzeta četiri uzorka kontaminiranog zemljišta, dok je kontrolni uzorak predstavljao nekontaminirano zemljište. Ispitivanje mikrobnog diverziteta (brojnost bakterija, gljiva i aktinomiceta) obavljeno je primenom standardnih metoda. Rezultati istraživanja ukazuju da je brojnost mikroorganizama zavisila od lokacije i prusustva/odsustva kontaminacije. U kontrolnoj varijanti brojnost svih ispitivanih grupa mikroorganizama bila je veća u odnosu na ostale uzorke. Brojnost bakterija u kontaminiranim uzorcima iznosila je od 1,21-6,88x106 CFU/g, gljiva 1,08-30,30x103 CFU/g i aktinomiceta 302,15-381,82x103 CFU/g. U kontrolnoj varijanti broj bakterija iznosio je 17,45x106 CFU/g, gljiva 54,02x103 CFU/g i aktinomiceta 481,91x103 CFU/g. Ovi rezultati ukuzuju na značaj ispitivanja mikrobnog diverziteta na kontaminiranim lokacijama i predstavljaju osnovu za potencijalne aplikacije bioremedijacionih tehnologija na području bivše fabrike 'Rog'

Bioremediation Potential Assessment of Plant Growth-Promoting Autochthonous Bacteria: a Lignite Mine Case Study

Coal and lignite play a major energy supply role in many European countries, including Bosnia and Herzegovina. Yet mining activities are a heavy source of ecosystem contamination, posing significant environmental threats. The primary goal of this study was to isolate and identify autochthonous lignite mine spoil bacteria and evaluate their potential in bioremediation of these polluted soils. Two Bacillus species, Bacillus simplex and a Bacillus cereus group member, were identified using conventional, molecular, and bioinformatics approaches. This represents, to our knowledge, the first microbial characterization of mine overburden in Bosnia and Herzegovina. A co-inoculum of autochthonous bacterial populations was used to treat unvegetated as well as oat- and lettuce-vegetated lignite overburden samples. Our results illustrate the potential of recovered native species to enrich soil fertility and productivity through plant growth promotion

Identifikacija rizosferne mikroflore kod biljne vrste Triticum aestivum

The collection of isolates has been made from rhizosphere of great number of divergent genotypes in order to identify the wheat's rhizosphere microflora. The genotypes were breed on the varietal test in Center for stubble wheat in Kragujevac. We have examined various characteristics on pure isolates e.g. morphological, biochemical, ecological and growing features. Determination was done by Bergey key (1974,1984). Out of 82 isolates there have been identified 39 of them to the species. We have assorted 25 isolates in family of Enterobacteriaceae. Genus Enterobacter and Klebsiella are dominant here. Family Pseudomonaceae (7 isolates) and family Azotobacteriaceae (3 isolates) are also quite present here. We have noticed the qualification of family Bacillaceae (4 isolates).U cilju identifikacije rizosferne mikroflore kod pšenice urađena je kolekcija izolata iz rizosfere velikog broja divergentnih genotipova pšenice, gajenih na sortnom ogledu Centra za strna žita u Kragujevcu. Čistim izolatima su ispitana morfološka, odgajivačka, biohemijska i ekološka svojstva. Determinacija je vršena po ključu BERGEY (1974, 1984). Od 82 ispitana izolata identifikovano je do vrste 39. U familiju Enterobacteriaceae svrstano je 25 izolata. Dominantno mesto zauzimaju rodovi Enterobacter i Klebsiella. Nađena je velika zastupljenost familije Pseudomonaceae (7 izolata) kao i familije Azotobacteriaceae (3 izolata). Uočena je pripadnost i familiji Bacillaceae (4 izolata)

The evolution of the eutrophication of the Palic Lake (Serbia)

Eutrophication is a world-wide environmental issue. The Palic Lake is a shallow lake typical for the Pannonian plain. The Lake itself was in a very bad condition during the late sixties of the last century; polluted and hypertrophic. Due to inadequate water quality, it was dried out in 1971 and re-established in 1977 and since then its trophicity has been worsening. The lake has recreational purposes but it is also a collector for treated municipal waste waters coming from the lagoons for active sludge water treatment. The sewage discharges from rapidly developing towns in the watershed and the growing use of fertilizers in agriculture increased the nutrient load to the Lake in the last decades. A steady increase of phosphorus loading is the most important factor of the lake eutrophication. The result of the accelerated eutrophication is the enormous amount of sediment at the bottom of the Palic Lake. Therefore, in the lake that covers an area of 565 ha and volume of 10 million m(3), there was 1.900.160 m(3) of sediment. The sediment thickness varied from 0.3 to 1.2 m. In summer 2010, the recreational part of the lake (sector IV) was 1.311.356 m(3) of sediment, characterized with concentrations of total phosphorus (TP) of 2885 mg/kg, 4300 mg/ kg total nitrogen (TN) and 39000 mg/ kg total organic carbon TOC. The sediment of the Palic Lake was not loaded with high concentrations of heavy metals. Everything mentioned supports the fact that the restoration of this aquatic system is necessary and applied measures have to be grounded on the principles of ecoremediation technologies