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ENHANCING YIELDS IN PEAT-FREE MEDIA THROUGH SYNERGISTIC EFFECTS OF MICROORGANISMS AND ORGANIC FERTILIZERS
No full textThe future of plant production will be shaped by the ecologically justified renunciation of peat as part of growing media and by a steadily growing proportion of ecological production processes. We investigated how combining microorganisms and organic fertilizers affects yields on peat-free growing media. An experiment was set up using a fully randomized block design, in which three vegetable species (lettuce, celery, Chinese cabbage) and a grass were grown on peat-free growing media in Mitscherlich vessels. Chicken dry manure and hydrothermally carbonized sheep wool served as fertilizers. Bacillus amyloliquefaciens, mycorrhizal fungi, and Bacillus amyloliquefaciens combined with mycorrhizal fungi were selected as microorganisms. This resulted in a total of 48 vessels per plant species. With the exception of celery, all species showed high yield increases when the application of organic fertilizers was combined with the application of bacteria and/or mycorrhizal fungi. Our results suggest that a combination of microorganisms and organic fertilizers is a promising approach for increasing yields of a variety of plants, when using peat-free growing media for plant producti
Antibacterial effects of coniferyl alcohol-derived dehydrogenation polymer on chlamydial infection in vitro
No full textChlamydia trachomatis, Gram-negative obligate intracellular bacteria, are a leading cause of sexually transmitted diseases worldwide, often causing severe complications. With no vaccine available and concerns about potential antibiotic resistance, the need for novel treatments is urgent. Dehydrogenation polymer of coniferyl alcohol in alginate hydrogel (DHP/Alg) has not yet been tested against chlamydial infections
Variscan Gornjane granitoid as an alternative cold-water reservoir in the ore-baring and mining area of eastern Serbia: Quantitative-qualitative characterization (Carpathian-Balkan belt, Getic unit)
No full textThe diminishing high-quality groundwater reservoirs have sparked significant interest in hard-rock aquifers, especially in active mining and raw material exploration areas. This paper aims to forecast the quantity and quality of alternative water resources in the area, thus facilitating the planning and design of the existing water resource systems. The focal point is the groundwater accommodated within basement-type alternative igneous aquifers nestled within an active mining and exploration province belonging to the Carpathian-Balkan fold-and-thrust belt (Banat-Timok Province/Banatitic Belt, sector in eastern Serbia). Despite their lower water-bearing capacity, we underscore the significant hydrogeological potential of natural water igneous-type aquifers, such as the Variscan Gornjane massif.
For the first time, this research identifies different reservoirs across the granite massif, providing a fresh perspective on the regional water resource systems. By categorizing reservoirs based on porosity type, flow rates, depth of reservoir rocks (in the depth range of 50 m), and distribution, this study significantly enhances the forecasting of the new water resource system, underlining the importance of this research in the field of water resources and mining. In addition to faulted sections of granite, aquifers are formed in the area characterized by weathered and decomposed granite fragments, often referred to as gruss deposits. The gruss layer has a flow rate reaching up to 0.01 l/s. In terms of the water quality, the groundwaters of the Gornjane granite massif mostly do not contain elements that are above the maximum permitted concentrations for drinking water. However, the occurrence of the elements Fe Mn in some water samples and the presence of Al Pb in one sample, as well as Se, As, Cu, Zn, Ag, Cd, Ga, and Bi, suggest the contact of water with sulfide mineralization detected in granite rocks of Rudna Glava-Tanda-Luka area, raising concerns about potential water quality issues
Enhancement of Bioactivity of Common Ash and Manna Ash Leaf Extracts Against Spongy Moth Larvae Using a Chitosan–Gelatin Biopolymer Matrix
No full textThis study investigated the bioactivity of common ash (Fraxinus excelsior L.) and
manna ash (Fraxinus ornus L.) leaf extracts, both in the crude form and incorporated into a
biopolymer matrix, against spongy moth (Lymantria dispar L.) larvae. Chemical analysis
revealed that both species were abundant in polyphenolic compounds, with common ash
containing significant quantities of p-hydroxycinnamic acid derivatives and verbascoside,
while manna ash was rich in coumarins, particularly aesculetin and aesculin. This study
evaluated the feeding deterrent activity, contact and digestive toxicity, effects on larval
nutritional indices, and larval development. Chitosan–gelatin-based biopolymer matrices containing the leaf extracts exhibited strong feeding deterrent activity at all tested
concentrations, while crude leaf extracts showed moderate deterrence. The biopolymer
matrices influenced spongy moth behavior only after digestion, resulting in reduced consumption and growth, as well as a prolonged duration of the third larval instar. No contact
toxicity was observed for the biopolymer matrices. Incorporating leaf extracts into the
chitosan–gelatin biopolymer matrix significantly enhanced their bioactivity against spongy
moth larvae compared with crude leaf extracts. The results suggest that biopolymer matrices containing common ash and manna ash leaf extracts are promising environmentally
friendly bioproducts for forest insect control, offering an innovative approach to managing
spongy moth populations and protecting forest ecosystems
Seasonal trends in water quality and their implications for water treatment technology in drinking water production
No full textGlavni fokus u cilju zaštite vode je plansko i naučno zasnovano iskorišćavanje vodnih resursa, kao i primena i optimizacija tehnoloških postupaka za pripremu pitke vode. Proizvodni pogon „Makiš“ snabdeva gotovo 60% stanovništva Beograda vodom za piće, prerađujući sirovu vodu iz reke Save pomoću Degremon (franc. Degremont) tehnologije. Upotreba koagulanta, flokulanta i hlora je neophodna kako bi kvalitet vode bio u skladu sa Pravilnikom o higijenskoj ispravnosti vode za piće. Cilj istraživanja bio je da se analiziraju sezonski trendovi u kvalitetu sirove vode reke Save i njihove implikacije na tehnologiju prerade površinske vode, kroz ispitivanje korelacije između fizičko-hemijskih parametara sirove vode i utroška hemikalija (koagulant, flokulant i hlor). Korišćenjem Pirsonove korelacione matrice, utvrđena je međusobna povezanost između kvaliteta sirove vode i količine primenjenih hemikalija, što je omogućilo optimizaciju tehnološkog procesa prerade i efikasnije upravljanje resursima.The primary objective of water protection is the planned and scientifically based management of water resources, along with the implementation and optimization of technological processes for drinking water treatment. The "Makis" water treatment plant, utilizing Degremont technology, meets nearly 60% of Belgrade's drinking water requirements by processing raw water sourced from the Sava River. The application of coagulants, flocculants, and chlorine is critical to ensuring that water quality adheres to the standards outlined in the Book of Rules regarding the hygienic safety of drinking water. This study aims to analyze seasonal variations in the quality of raw water from the Sava River and their implications for surface water treatment technology by investigating the correlation between the physicochemical parameters of raw water and the consumption of treatment chemicals (coagulants, flocculants, and chlorine). By employing Pearson's correlation matrix, we can ascertain the relationship between raw water quality and the amount of chemicals used, facilitating the optimization of the treatment process and enhancing resource management efficiency
Bridging structure and sensitivity: SnO2 nanofibers for NO2 sensing
No full textIndustrial growth and vehicular emissions have worsened air pollution, contributing to global
challenges like climate change and ecosystem disruption. Nitrogen dioxide (NO2), primarily
emitted from transportation and industrial processes, poses a significant health threat even at
low concentrations (~30 ppb), highlighting the urgent need for sensitive, cost-effective NO2
sensors. Semiconducting nanofibers, fabricated using electrospinning, are promising for
enhancing gas sensing performance. Electrospinning controls nanofiber morphology, creating
a highly porous and interconnected structure that increases surface area and improves gas
diffusion, key factors for boosting sensor sensitivity and efficiency. This paper explores the
fabrication of multi-porous tin dioxide (SnO2) nanofibers via electrospinning and their
application in detecting varying concentrations of NO2. By fine-tuning the ratio of
polyvinylpyrrolidone (PVP) to Sn-precursor, we achieved fibers with multiple pore channels,
improving gas diffusion and surface reactivity. After electrospinning, the fibers were calcined
at 550 oC to induce crystallization and pore development. Structural analysis revealed the
formation of multi-porous fibers with diameters ranging from 30 to 130 nm, exhibiting a high
surface area of 75 m²/g, an average pore radius of 4.5 nm, and crystallite sizes of approximately
15 nm. The nanofibers were processed into thick films on Al₂O₃ substrates with interdigitated
electrodes and microheaters via screen printing. The sensors, tested with controlled NO2
concentrations, exhibited excellent sensitivity, quick response, and recovery times, showcasing
their potential for sub-ppm NO2 detection. This study emphasizes the effectiveness of
electrospinning as a method for tailoring the structure and functionality of SnO2 nanofibers,
paving the way for next-generation NO2 sensors for real-time environmental monitoring
Green synthesis of polyphenol-derived nanoparticles from the branches of Picea omorika (Pančić) Purkynĕ and potential biomedical applications
No full textPolyphenolic compounds, with a particular focus on lignans, were extracted from the branches of Picea omorika (Pančić) Purkynĕ through an ethanol and water extraction. The lignans served as the basis for nanoparticle synthesis using ethylenediamine as a cross-linking agent during the hydrothermal process, while chemical synthesis was carried out using various amino acids as cross-linking agents. The synthesis of nanoparticles from Picea omorika (Pančić) Purkynĕ branches represents a sustainable alternative to conventional methods.
The obtained nanoparticles were characterized using Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM), which revealed that the particle sizes were less than 200 nm. The particles also demonstrated moderate antioxidant activity against the DPPH radical, as determined by EPR spectroscopy. Special attention is given to their antimicrobial potential, which will be evaluated against selected microbial strains.
As bioactive polyphenols, lignans possess inherent biological properties, including antioxidant and antimicrobial potential that may be enhanced or modulated at the nanoscale. These findings may support the development of novel nanoformulations for biomedical applications (e.g., wound dressings, drug delivery), food preservation, or environmentally friendly protective coatings
Employing microalga Chlorella sorokiniana in the biosynthesis of paramagnetic and catalytically functional manganese cluster
No full textFinding vehicles for biosynthesis of metal clusters with advantageous magnetic and catalytic properties is an
important industrial and environmental task. We have found previously that green microalga Chlorella sorokiniana produces a multivalent Mn-O cluster with structure that is similar to photosynthetic oxygen-evolving
complex (OEC). Here we reported magnetic and redox properties and the site of accumulation of this cluster,
and we proposed the mechanisms of biosynthesis and the protocol for extraction. The cluster was paramagnetic
even at room temperature, with an antiferromagnetic transition at ~13 K. The separation between ground and
excited state of ΔE ≈ 15.0 cm− 1 matched the separation energy of OEC in S2 state. Nano X-ray fluorescence
microscopy and 31P NMR showed that the cluster is accumulated in acidocalcisomes, a lysosome-type organelles
rich in polyphosphates. The conditions in these organelles resemble the settings of chemical synthesis of OEC
mimics, including mildly acidic pH and the availability of Ca2+ ions. Polyphosphates are likely to play a role of stabilizing ligands and modulators of redox properties of Mn2+ in the cluster synthesis. The cluster shares redox
potentials with OEC and showed catalase-like activity. However, we could not confirm OEC-like performance
because the cluster was prone to degradation by oxidizing agents in the presence of organic residue in the extract.
The biosynthesis showed an overall yield of ~25 % and appears to be cost-competitive with chemical synthesis.
This study shows that metabolic trades of selected microalgae can be employed in the green synthesis of catalytically functional clusters
Effect of silicon fertilization and crop rotation on PhytOC sequestration in Vojvodina wheat production systems
No full textCarbon dioxide (CO₂) is the primary greenhouse gas driving global warming, with annual emissions
projected to reach 80 billion tons by 2050. One promising pathway for terrestrial carbon (C)
sequestration is the occlusion of C within plant silica formations – phytoliths (PhytOC). To evaluate
potential of wheat for PhytOC-based CO₂ sequestration, a field survey was conducted in the Vojvodina region (Serbia), which accounts for 55% of the country’s wheat production. Wheat straw and topsoil samples (plough depth) were collected from 25 sites under typical farming practices involving crop rotation (mostly maize and sunflower, rarely soybean or sugar beet) and NPK fertilization. PhytOC concentrations ranged from 50-260 mg kg⁻¹ in topsoil and 40-860 mg kg⁻¹ in wheat straw, revealing considerable genotypic variation. To assess the effect of Si fertilization, both soil (150 kg Si ha⁻¹) and foliar (1 mM H₄SiO₄) applications were tested. Compared to untreated control, straw phytolith content increased by 30% and 50% with foliar and soil Si, respectively. Correspondingly, straw biomass increased from 8.34 t ha⁻¹ (control) to 9.45 t ha⁻¹ (foliar Si) and 9.53 t ha⁻¹ (soil Si), nearly doubling PhytOC yield in the Si treatments. A 60-year crop rotation trial further examined the long-term effects on PhytOC sequestration. Compared to monoculture wheat, two-crop (maize–wheat) and three-crop (maize–soybean–wheat) rotations increased wheat biomass (by 1.3 and 1.7 times), leaf Si concentration (by 1.3 and 1.6 times), and straw phytolith accumulation (by 2.4 and 2.6 times), resulting in nearly double PhytOC yields (160 and 150 mg kg⁻¹ vs. 90 mg kg⁻¹). Soil PhytOC storage increased by 25% in three-crop systems (two grains and a legume) compared to monoculture, and by 60% in two grain crops rotations. In Vojvodina, PhytOC-based CO₂ sequestration in soil (at plough depth) is estimated at 334 kg CO₂ ha⁻¹, while wheat straw captures approximately 15 kg CO₂ ha⁻¹ annually, corresponding to an estimated 5,500,000 kg CO₂ yr⁻¹ across the region. These findings highlight that wheat’s capacity for PhytOC-based CO₂ sequestration can be substantially improved through genotypic selection, Si fertilization, and diverse crop rotations, offering a sustainable strategy for climate-smart agriculture
Phloem mobility and leaf remobilization of silicon in cucumber
No full textThe possibility of silicon (Si) remobilization from leaves and its transport via the phloem remains a subject of ongoing debate. Recently, Si was detected in rice phloem sap at concentrations exceeding saturable levels; however, a direct transport pathway via the phloem has yet to be confirmed (Yamaji et al., Nature Communications 15: 10712, 2024). Our earlier research showed that plants cannot distinguish between Si and its chemical analog, germanium (Ge). Therefore, Ge was used as a tracer to investigate potential phloem-mediated Si transport. Cucumber (Cucumis sativus L.) plants, used as a model high Si-accumulating dicot species, were grown hydroponically to the three-leaf stage, and 1 mM Ge(OH)₄ was carefuly applied to the second leaf. After five days, plants were harvested and separated into roots and leaves collected from seven positions (from the base to the apex). In foliarly treated (+Ge) and untreated (–Ge) plants, Ge concentrations were measured in roots (575 vs. 45 ng g⁻¹), first leaf (1995 vs. 45 ng g⁻¹), fourth leaf (3139 vs. 29 ng g⁻¹), and seventh leaf with apex (2955 vs. 30 ng g⁻¹), respectively. Since both downward movement to roots and upward transport to developing tissues (lacking fully developed xylem) can occur only via the phloem, these results provide direct evidence of phloem-mediated transport of Ge as a functional analog of Si. Nevertheless, interaction with adjacent xylem elements cannot be excluded. To assess Si remobilization, cucumber plants were grown under three treatments: continuous Si supply (+Si), Si-free nutrient solution (–Si), and pulsed Si supply (Si withdrawn at the second-leaf stage; +/–Si), under either Fe-sufficient (+Fe) or Fe-deficient (–Fe) conditions. Silicon contents in the youngest tissues (fourth leaf and apex) of +Si, –Si, and +/–Si plants were 953, 16, and 29 μg Si leaf⁻¹, respectively. Under Fe deficiency, Si accumulation in youngest tissues further increased (49 μg leaf⁻¹), likely due to elevated citrate levels in –Fe plants. Our previous work also showed that Si enhances Fe remobilization from older to younger leaves (Pavlović et al., Annals of Botany 118: 271-280, 2016). Overall, these findings provide the first direct evidence of Si mobility via the phloem (from leaf to root) and demonstrate that xylem-delivered Si can be remobilized form older leaves and subsequently retranslocated to young expanding leaves, particularly under Fedeficient conditions. Ongoing research using stable isotopes ²⁹Si and ³⁰Si aims to further confirm Si retranslocation