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Salix L. clones grown in habitat with heavy metals for use in cocombustion with coal
No full textPurpose and backround: Bioenergy is one of the possibilities that can be obtained from different
sources of biomass. One of the sources is the cultivation of fast-growing short-rotation deciduous
trees, which give a large amount of biomass per hectare. The purpose of the research is
the plantation of 4 clones of willows, namely 3 clones of Salix alba and 1 clone of Salix viminalis to
improve the caloric value of coal. Material and work method: The experiment was set with clones:
Salix alba - clone B-44; clone 347; clone NS 73/6 and Salix viminalis contaminated with a mixture
of heavy metals (As, Cd, Cr, Cu, Ni, Pb). Adequate methods were used to investigate the chemical
properties of the soil, heavy metal content and the energetic efficiency of the obtained biomass
(in the proportion of 5%, 10%, 15% and 20%), to improve the caloric value of coal. The obtained
data were statistically processed using adequate statistical methods. Obtained results: The obtained
results indicate that there are differences between the clones. Based on the data, it can be
concluded that the improvement of the caloric value of coal (13686 kJ/kg) with willow biomass
(18124 kJ/kg) depends less on the genotype, more on the sample of coal and the proportion of
biomass. The economically profitable share of willow biomass is up to 5-10
Factors threatening fish species in Serbia
No full textSlatkovodni ekosistemi, iako prostorno ograničeni, igraju ključnu ulogu u očuvanju globalne biodiverzitetske raznolikosti i pružanju ekosistemskih usluga. Ipak, slatkovodne vrste, posebno ribe, suočene su s ubrzanim izumiranjem zbog kombinovanih negativnih uticaja ljudskih aktivnosti – uključujući zagađenje, krivolov, gubitak staništa, prisustvo invazivnih vrsta i klimatske promene. U Srbiji su dodatni problemi neusklađeno upravljanje vodnim resursima i nedostatak znanja o biologiji i distribuciji vrsta. Poseban problem predstavlja neadekvatno prečišćavanje otpadnih voda, što ugrožava vodene resurse i staništa brojnih vrsta.Although freshwater ecosystems occupy a very limited area, they play a crucial role in maintaining global biodiversity and providing essential ecosystem services. However, freshwater species—especially fish—are facing accelerated extinction due to various human-induced pressures, including pollution, overfishing, habitat loss, invasive species, and climate change. In Serbia, additional challenges include poorly coordinated water resource management and limited knowledge of species biology and distribution. A significant issue is the inadequate treatment of wastewater, which threatens aquatic resources and the habitats of numerous species
Investigation of Novel Radical Scavenging Mechanisms in the Alkaline Environment: Green, Sustainable and Environmentally Friendly Antioxidative Agent(s)
No full textPharmaceutical and industrial utilization of synthetic chemicals has an immerse impact
on the environment. In that sense, novel chemicals with potential for industrial
application should be investigated for their behavior in reactions with hydroxyl radical,
simulating AOPs (Advanced Oxidation Processes). AOPs are known for being highly
effective in wastewater management and natural water remediation. In this paper,
exhaustive research on the radical scavenging activity of a newly synthesized
coumarin derivative (4HCBH), as a representative of the series of coumarin-
benzohydrazides with high antioxidative potential was conducted. This study took into
consideration the pH value range significant for practically all living organisms (pH=7.0-
8.5). According to the experimentally obtained results, the 4HCBH showed an increase
in radical scavenging activity, following the slight increase in pH values, which
suggested that the formation of anionic form of 4HCBH is responsible for its antiradical
activity. Further investigations led to the postulation of a novel mechanistic approach
called Sequential Proton Loss Electron Transfer – Radical-Radical Coupling (SPLET-
RRC), in which, by a series of steps, a new, stable compound was formed.
Furthermore, it was demonstrated that the product generated through SPLET-RRC
showed lower toxicity than the parent molecule
Phytoremediation Potential of Different Genotypes of Salix alba and S. viminalis
Get PDFElevated concentrations of heavy metals result in soil degradation, a reduction in plant
yields, and a lower quality of agricultural products, which directly endangers people, animals, and
the ecosystem. The potential of three clones of Salix alba (347, NS 73/6, and B-44) and one genotype of
S. viminalis for the phytoextraction of heavy metals was investigated, with the aim of identifying the
most physiologically suitable willow genotypes for use in soil phytoremediation. The experiment was
placed on the contaminated soil substrate collected in Kolubara Mining Basin (Serbia), enriched by
high loads of heavy metal salts, and a control medium. Significant differences in the concentrations
of heavy metals were recorded between the contaminated and control plant material, especially
when it comes to nickel (Ni), copper (Cu), cadmium (Cd), and lead (Pb), confirming that S. alba and
S. viminalis are hyperaccumulator species of heavy metals. Clone 347 shows the greatest uptake of
Cd and chromium (Cr), and clone B-44 takes up these metals only to a lesser extent, while clone
NS 73/6 shows a less pronounced uptake of Cr. The roots have the greatest ability to accumulate
Ni and Pb, Cu is absorbed by all plant organs, while Cd is absorbed by the leaves. The organ that
showed the greatest ability to accumulate heavy metals was the root, which means that willows have
a limited power to translocate heavy metals to above-ground organs. The studied genotypes of S. alba
have a higher potential for the phytostabilization of Cu and Cd, as well as the phytoextraction of
Cd, compared with S. viminalis. The results confirm the assumption of differences between different
willow genotypes in terms of the ability to phytoextract certain heavy metals from soil, which is
important information when selecting genotypes for soil phytoremediation
VARIABILITY OF ANATOMICAL AND MORPHOLOGICAL TRAITS OF PINUS NIGRA AND PINUS SYLVESTRIS SEEDLINGS AFFECTED BY DIFFERENT CONTAINER TYPE
Get PDFIn the paper was analysed the influence of three different container types, used for
cultivation of Pinus nigra and Pinus sylvestris seedlings, on dimensions of their anatomical
(resin ducts width, resin ducts number, tracheid number, tracheid width, wood rays height) and
morphological (height, root collar diameter, sturdiness coefficient) elements, and on proportion
of wood, bark and pith, as well. Two-factorial ANOVA showed that container type affects a lot
all investigated anatomical traits by both species, but on the other side, these species varied
between each other just in terms of tracheid width and wood rays height. Based on descriptive
statistics, significantly lower values of all studied anatomical elements were recorded by
biodegradable compared to plastic containers. As for P. nigra seedlings, they showed the best
anatomical performance in Plantagrah I, while Hiko V-120 SS was the most suitable for
P. sylvestris. The highest proportion of pith and bark was recorded in biodegradable container.
As for morphological parameters, such as height and root collar diameter, higher values were
recorded by plastic containers
Sourcing Chitin from Exoskeleton of Tenebrio molitor Fed with Polystyrene or Plastic Kitchen Wrap
Get PDFIn this work we have characterized and compared chitin sourced from exoskeleton of Tenebrio molitor larvae fed with polystyrene or plastic kitchen wrap combined with bran in the ratio 1:1 with chitin sourced from larvae exoskeleton fed only with bran. Analysis of the frass by ATR-FTIR showed very similar spectra and confirmed degradation of the plastic feed components, while ATR-FTIR analysis of the exoskeleton verified the absence of any plastic residue. Deproteinization followed by demineralization produced 6.78 -5.29 % chitin, showing that plastic (polystyrene or plastic kitchen wrap) in the larvae diet resulted in heavier insect exoskeleton, but yielded slightly less chitin, with the lowest value obtained for plastic kitchen wrap in the insect diet. The deacetylation degree of 98.17-98.61% was determined from measured ATR-FTIR spectra. XRD analysis confirmed the presence of -chitin with a crystallinity index of 66.5-62% and crystallite size 4-5 nm. Thermogravimetric analysis showed similar degradation curves for all chitin samples, with two degradation steps. These results show that chitin sourced from exoskeleton of T. molitor larvae fed with plastic (polystyrene or plastic kitchen wrap) and contributing to significant biodegradation of major polluting materials can be a feasible and alternative source of chitin, further promoting a bio-circular economy
In vitro Evaluation of Acaricidal Efficacy of Selected Essential Oils against Dermanyssus gallinae
Get PDFIntensification of poultry production has been associated with an increase in parasite prevalence and adaptation of an invasive external parasitic species, such as the poultry red mite (Dermanyssus gallinae). The studies of biological efficacy (contact and fumigant) and level of toxicity to mites indicated that the external application of essential oils (EOs) can be an alternative to acaricides. In this study, the results of acaricidal efficacy of eight selected EOs - Lavandula angustifolia Mill., Laurus nobilus L., Mentha x piperita L., Mentha spicata L., Ocimum basilicum L., Salvia officinalis L., Satureja montana L. and Thymus vulgaris L. are presented. Their chemical profiles were analyzed by gas chromatography coupled with mass spectrometry (GC–MS). The acaricidal efficacy of EOs (6% concentration) was tested on adult mites over 10 days in laboratory conditions using the Petri-dish method, through direct exposure for 1 min (contact toxicity) and subsequent exposure for 1 h (residual toxicity). The most effective EO in direct exposure-contact, after 48 h of observation, was S. montana (100% toxicity), while the greatest residual effect was observed in T. vulgaris (11% toxicity). The obtained results showed high efficacy of the EOs against the mites through direct contact and thus their great acaricidal potential. However, the activity was lost with subsequent exposure, indicating the absence of prolonged effect. Possible ways to overcome this problem are discussed further in this paper. In any case, the present study confirmed the acaricidal potential of herbal medicines that can be used in the integrated control of poultry red mite
Assessment of growth-promoting properties of Pseudomonas spp. on soybeans under field conditions
Get PDFThe soybean is recognized worldwide as one of the most important crops due to its protein- and
oil-rich seeds. Several beneficial bacterial strains, including those of the genus Pseudomonas, are
known to increase plant yield and disease tolerance. The aim of this study was to test the potential of 15 strains of Pseudomonas spp. to promote soybean growth under field conditions. Strains were identified based on 16S rRNA and gyrB sequences, and strains belonging to risk group 1 were further analyzed. Selected strains were tested for plant growth-promoting (PGP) properties, biofilm formation and in vitro antimicrobial activity against various fungal pathogens. PGP activity indicators of the selected strains were evaluated on soybean plants grown in fertilizer-free soil and in soil treated with 70% and 100% fertilizers. Three Pseudomonas spp. strains, P. putida VB131A, P. fulva VB134B and P. rhodesiae VB143S, were selected as PGP candidates. All three strains showed the ability to produce IAA and solubilize phosphorus, while only P. rhodesiae VB143S showed strong lipase and protease activity. Only P. fulva VB134B showed the ability to
produce biofilm and hydrogen cyanide. All three strains showed in vitro antifungal activity against
Alternaria infectoria. P. fulva VB134B and P. rhodesiae VB143S showed antifungal activity against
Alternaria alternata and P. putida VB131A and P. rhodesiae VB143S against Epicoccum nigrum. Only P. fulva VB134B showed activity against Monilinia laxa. Statistically significant differences in
plant height were not observed regardless of the strain or soil treatment used. In terms of first
pod height, the P. fulva VB134B treatment was most effective when applied to soybeans grown
in 100% fertilized soil. In contrast, plants treated with P. rhodesiae VB143S and grown in 100% fertilized soil had the highest number of branches and pods per plant
Phenol and textile dye removal from wastewater with immobilized peroxidases from Horseradish (Armoracia rusticana) and white rot fungi (Phanerochaete chrysosporium)
Get PDFSve veći globalni problem predstavlja zagađenje vodenih sistema razičitim otpadnim
materijama, pre svega fenolnim jedinjenjima i organskim bojama ispuštenim iz mnogobrojnih
industrijskih postrojenja. S obzirom da su fenoli označeni kao najčešći zagađivači voda širom
sveta, pronalazak metoda za njihovo uklanjanje predstavlja jedan od najvećih izazova
savremene naučne zajednice. Različiti biokatalizatori su pronašli primenu u ove svrhe, a među
njima je posebno mesto zauzela peroksidaza iz rena (HRP). Kao najveće ograničenje ove metode
navodi se inaktivacija enzima, koja se može prevazići njegovom imobilizacijom na različitim
nosačima.
U ovom radu su razvijene metode za uklanjanje fenola i degradaciju tekstilnih boja
imobilizovanom peroksidazom iz rena i ćelijskim zidovima sa lignin-peroksidazom (LiP). Kao
nosači za imobilizaciju su korišćeni oksidovani alginati modifikovani tiraminom, makroporozni
kopolimeri različite veličine pora, kao i neorganski glineni nosač – sepiolit.
Tiramin-alginatne mikro-kuglice su iskorišćene za enkapsulaciju peroksidaze iz rena
primenom kuplovane emulziono-polimerizacione reakcije. Ispitan je uticaj stepena
modifikacije alginata tiraminom na specifičnu aktivnost enzima. Ustanovljeno je da sa
povećanjem koncentracije perjodata korišćenog za oksidaciju alginata od 2,5 do 20 mol% pre
modifikacije tiraminom dolazi do postepenog povećanja specifične aktivnosti.
Imobilizovana HRP je potom upotrebljena za uklanjanje fenola u šaržnom reaktoru.
Optimizovani su reakcioni uslovi sa ciljem postizanja visokog stepena efikasnosti i poboljšane
kontinualne primene. Za interno generisanje vodonik-peroksida (H2O2) tokom oksidacije
fenola primenjen je sistem sastavljen od glukoze i glukoza-oksidaze. Znatno veći stepen
uklanjanja fenola (96%) iz reakcionog sistema za 6 h je postignut primenom interne dostave
H2O2, dok se njegovim direktnim dodavanjem značajno smanjuje efikasnost uklanjanja fenola
na 42%. Primenom glukoza-oksidaze u koncentraciji od 0,187 U/mL i 4 mmol/L glukoze
postiže se najveća efikasnost, kao i korišćenjem 20 mol% oksidovanog i modifikovanog tiraminalginata
za enkapsulaciju HRP.
Degradacija tekstilnih boja ostvarena je i primenom ćelijskih zidova sa ligninperoksidazom
(LiP) zarobljenih u kalcijum-alginatnom hidrogelu. LiP je imobilizovana na
tiramin-alginatne mikro-kuglice. Inkubacijom enkapsuliranih ćelijskih zidova u rastvorima
boja Evans Blue i Amido Black 10B tokom 48 h i merenjem njihove aktivnosti u određenim
vremenskim intervalima uočeno je postepeno povećanje procenta degradacije sa periodom
inkubacije. Nakon maksimalne inkubacije 86% boje Evans Blue se dekolorizuje, dok taj
procenat za Amido Black 10B iznosi 84%. Ponovnom upotrebom ćelijskih zidova sa LiP
ostvarena je efikasna degradacija navedenih boja tokom 12 uzastopnih ciklusa.
Makroporozni kopolimeri sastavljeni od glicidil metakrilata i etilen glikol dimetakrilata
veličine čestica od približno 2 μm i različite veličine pora (150–310 nm) su sintetisani
disperzionom polimerizacijom i modifikovani etilendiaminom. Dve različite metode,
perjodatna i glutaraldehidna, su korišćene za imobilizaciju peroksidaze iz rena na ovim
polimerima.
Aktivnost imobilizovanog enzima je u direktnoj vezi sa veličinom pora na nosaču
korišćenom za imobilizaciju. Imobilizacijom HRP perjodatnom metodom na poli(GMA-co-
EGDMA) veličine pora od 234 nm dobijena je specifična aktivnost od 9,65 U/g nosača, dok je
HRP na kopolimeru sa porama od 297 nm imala specifičnu aktivnost 8,94 U/g nosača. Takođe
je došlo i do povećanja stabilnosti imobilizovane peroksidaze na 65 °C u vodenom rastvoru kao
i u organskom rastvaraču.
Dobru stabilnost na različitim pH vrednostima, kao i povećanu Km vrednost tokom
oksidacije pirogalola, pokazala je peroksidaza imobilizovana na makroporoznom kopolimeru
sa veličinom pora od 234 nm, koja je imala i najveću specifičnu aktivnost. Nakon 5 ciklusa
ponovne upotrebe za oksidaciju pirogalola zadržano je 80% inicijalne aktivnosti. Imobilizovani
enzim skladišten 14 dana u odgovarajućem puferu zadržao je 98% aktivnosti. Značajna
efikasnost uklanjanja fenola pri optimizovanim uslovima za dostavu vodonik-peroksida u
reakcioni sistem je postignuta primenom HRP imobilizovane na kopolimeru sa porama veličine
234 nm.
Sepiolit je primenjen za adsorpciju nativne HRP i HRP oksidovane natrijum-perjodatom.
Dodate su različite količine oba enzima po gramu sepiolitnog nosača. Sa povećanjem količine
peroksidaze povećava se specifična aktivnost imobilizovanog enzima. Najveća aktivnost je
postignuta pri imobilizaciji 15 mg perjodatno-oksidovane peroksidaze po gramu sepiolita.
Testirane su temperaturna i operativna stabilnost imobilizovanih peroksidaza, kao i stabilnosti
na različitim pH vrednostima. Oksidovana peroksidaza je zadržala 42% inicijalne aktivnosti
nakon 4 uzastopna ciklusa oksidacije pirogalola.A growing global concern is the pollution of water courses with various waste materials,
primarly phenolic compounds and organic dyes released from numerous industrial plants.
Since phenols are designated as the most common water pollutants worldwide, finding
methods for their removal is nowadays one of the biggest challenges for the broad scientific
community. To this end, various biocatalysts have been used, among them Horseradish
peroxidase (HRP) has been in prime position. The main limitation of this method is an enzyme
inactivation, which can be overcome by its immobilization on different carriers.
In this study, various methods for the removal of phenol and degradation of textile dyes by
immobilized Horseradish peroxidase and cell walls with lignin peroxidase (LiP) were
developed. Oxidized alginates modified with tyramine, macroporous copolymers with different
pore characteristics, as well as inorganic clay mineral – sepiolite, were used as carriers in
immobilization.
Tyramine-alginate micro-beads were used for the encapsulation of peroxidase by coupled
emulsion polymerization reaction. An effect of a degree of the alginate modification by tyramine
on the specific activity of enzyme was examined. A gradual increase in the specific activity, with
an increase in the concentration of periodate used for oxidation of alginate from 2.5 to 20 mol%
prior to modification by tyramine, was observed.
Immobilized HRP was then used for the removal of phenol in a batch reactor. Reaction
conditions were optimized with an aim of achieving a high degree of efficiency and improved
reusability. A system composed of glucose and glucose oxidase was used for internal generation
of hydrogen peroxide (H2O2). When internal delivery of H2O2 was employed, 96% of phenol was
removed from the reaction system in 6 h, whereas its straightforward addition significantly
reduced the efficiency of phenol removal (42%). The highest efficiency was achieved by using
glucose oxidase at the concentration of 0.187 U/mL and 4 mmol/L of glucose, as well as by using
20 mol% periodate-oxidized and modified tyramine-alginate for HRP encapsulation.
Degradation of textile dyes was performed by employing cell walls with lignin peroxidase
(LiP) entrapped in a calcium-alginate hydrogel. LiP was also imobillized on tryamine-alginate
micro-beads. By incubating encapsulated cell walls in Evans Blue and Amido Black 10B dye
solutions for 48 h and measuring their activity in certain time intervals, a gradual increase in
the degree of degradation with incubation period was observed. Maximal incubation in Evans
Blue dye leads to 86% decolorization, whereas that percent for Amido Black 10B is 84%
Efficient degradation of previously mentioned dyes was achieved within 12 consecutive cycles
by reusing cell walls with LiP.
Macroporous copolymers composed of glycidyl methacrylate and ethylene glycol
dimethacrylate with a particle size of approximately 2 μm and different pore sizes (150–
310 nm) were synthesized by dispersion polymerization and modified with ethylenediamine.
Two methods, periodate and glutaraldehyde method, were used for the immobilization of horseradish peroxidase onto these polymers.
The activity of immobilized enzyme is affected by the pore size of the carrier used for
immobilization. By immobilizing HRP using the periodate method onto poly (GMA-co-EGDMA)
copolymers with the pore size diameter of 234 nm specific activity of 9.65 U/g of carrier was
obtained, whereas HRP immobilized onto carrier with the pore size diameter of 297 nm showed
specific activity of 8.94 U/g of carrier. Also, the stability of immobilized peroxidase at 65 °C, as
well as in an organic solvent, was increased.
Peroxidase immobilized onto macroporous copolymer with a pore size diameter of 234 nm
and the highest specific activity also showed a good stability at different pH values, as well as
the increased Km value during the oxidation of pyrogallol. Eighty percent of the initial activity
was retained after 5 consecutive cycles of pyrogallol oxidation. After storing the immobilized
enzyme for 14 days in appropriate buffer, 98% of its activity was preserved. A significant
efficiency of phenol removal under optimized conditions for the delivery of hydrogen peroxide
into the reaction mixture was achieved by applying HRP immobilized onto copolymer with the
pore diameter of 234 nm.
Sepiolite was used for the adsorption of native HRP and HRP oxidized with sodium
periodate. Different amounts of both enzymes were added per gram of sepiolite carrier.
Increase in the amount of peroxidase leads to the increase in the specific activity of immobilized
enzyme. The highest activity was achieved when 15 mg of periodate-oxidized peroxidase was
immobilized per gram of sepiolite. Temperature and operational stabilities of immobilized
peroxidases were tested. Oxidized peroxidase retained 42% of initial activity after
4 consecutive cycles of pyrogallol oxidation
Evolutionary dynamics and geographical dispersal of Borrelia lusitaniae
Get PDFBackground: Borrelia lusitaniae is a species within the complex Borrelia burgdorferi sensu lato, associated with lizards as reservoirs and Ixodes ricinus as its main vector. Borrelia lusitaniae is predominantly distributed in Central and Southeast Europe, and in countries of the Mediterranean basin, such as Portugal, Morocco, Tunisia, and Italy where this spirochete appears to infect vector ticks more frequently than other genospecies. Evolution of this zoonotic tick-borne microparasite is shaped by different environmental factors. Comprehensive phylogenetic analysis may give insight into how B. lusitaniae spreads to new geographic locations.
Aim: We applied Bayesian statistical methods to B. lusitaniae multilocus sequence typing (MLST) data to study the migration routes of B. lusitaniae and its potential for further spread.
Results: The discrete phylogeographic analysis placed origins of B. lusitaniae in Southeast Europe and identified at least two introductions of B. lusitaniae from Europe to North Africa. Estimated effective reproductive potential (Re), as a key indicator for a pathogen spread, suggested potential for further spread.
Conclusion: The results of this study can provide beneficial information about the potential for further spread of B. lusitaniae in Europe and North Africa and estimation of necessity for the development of strategies to monitor and control Lyme borreliosis