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Amidst worsening climate change, drought stress imperils global agriculture, jeopardizing crop yields and food security, thereby necessitating the urgent exploration of sustainable methods like biopriming for the harnessing of beneficial microorganisms to bolster plant resilience. Recent research has revealed diverse biological compounds with versatile applications produced by Schizophyllum commune, rendering this fungus as a promising contender for biopriming applications. For the first time, this study aimed to investigate the potential of S. commune exo- (EPSH) and intra-polysaccharides (IPSH) isolated from two strains—Italian (ITA) and Serbian (SRB)—under submerged cultivation to enhance the resilience of Pisum sativum L. seeds through the biopriming technique. Testing of the seed quality for the bioprimed, hydroprimed, and unprimed seeds was conducted using a germination test, under optimal and drought conditions, while characterization of the PSHs included FTIR analysis, microanalysis, and determination of total protein content (TPC). The FTIR spectra of EPSH and IPSH were very similar but revealed the impurities, while microanalysis and TPC confirmed a different presence of proteins in the isolated PSHs. In optimal conditions, the IPSH SRB increased germination energy by 5.50% compared to the control; however, the highest percentage of germination (94.70%) was shown after biopriming with the PSH isolated from the ITA strain. Additionally, all assessed treatments resulted in a boost in seedling growth and biomass accumulation, where the ITA strain demonstrated greater effectiveness in optimal conditions, while the SRB strain showed superiority in drought conditions. The drought tolerance indices increased significantly in response to all examined treatments during the drought, with EPSH ITA (23.00%) and EPSH SRB (24.00%) demonstrating the greatest effects. Results of this preliminary study demonstrate the positive effect of isolated PSH, indicating their poten

Polyethylene terephthalate (PET) is a plastic material that poses a significant global concerndue to its durability and resistance to degradation. One effective method for minimizing PETwaste is through microbial degradation, resulting in the production of ethylene glycol andterephthalic acid (TA). Terephthalic acid, as a PET monomer, holds promise as a modelcompound for further exploration into PET plastic degradation and valorisation.

Aim of this study wvas to determine effects of levan and pullulan on bioluminescence of A. fischeri after acute Cu2+ exposure.

In the present study graft copolymers combining starch with polystyrene (S-PS) or methacrylic acid were (S-MA) were synthesized and its biodegradable potential was investigated.

In the present study graft copolymer with microbial levan and polystyren was synthesized and its biodegradable potential inliquid and soil medium was investigated.

Razvoj hemijske industrije u prošlom veku pozitivno je uticao na životni standard, ali je za sobom ostavio značajne količine toksičnih supstanci u životnoj sredini. Dugotrajne organske zagađujuće supstance (Persistant Organic Pollutants - POPs) su antropogene hemikalije koje se zadržavaju, akumuliraju u lancu ishrane i imaju štetne posledice po zdravlje ljudi i životnu sredinu [1]. Per- i polifluoralkil supstance (PFAS) kao što su perfluorooktanska kiselina (PFOA), perfluorooktan sulfonska kiselina (PFOS) i od 2022. godine perfluoroheksan sulfonska kiselina (PFHxS) se nalaze na listi POPs hemikalija [2]. Publikacije proistekle iz istraživanja na temu PFAS supstanci ukazuju da mikroorganizmi koji su izolovani iz životne sredine zagađene ovim jedinjenjima mogu smanjiti količinu istih usled biosorpcije, ali i potencijalne biotransformacije i biodegradacije [3,4].

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals with extremely strong C-F bonds. Due to their thermal stability, acid resistance, and high surface activity, they have been widely used for several decades in various consumer products. PFAS has been detected in water, soil, sediment, air, food, and biota samples on all continents and due to this are recognized as environmental and human health risk (Carlson et al. 2022). In the last decade, several available technologies were tested for the remediation of PFAS-polluted environments, such as adsorption, filtration, thermal destruction, oxidation/reduction, and soil washing, but several disadvantages were reported (Bolan et al., 2021). We hypothesize that by using advanced oxidation techniques followed by microbial treatment decrease in the concentration of PFOA as a PFAS model compound will occur. In the beginning, we tested separately abiotic and biotic degradation of PFOA. Target LC-MS/MS was used for quantitative analysis of PFOA decrease, and for detecting degradation products, nontargeted LC-MS/MS analysis was used. In the photocatalysis study, we used selected Ti and Al-based photocatalysts. The experiments were conducted at 20 °C in an open cylindrical polypropylene reactor, and a simulated solar radiation lamp (Solimed BH Quarzlampen) was used as a light source. Microbial communities were isolated from the locations in Serbia, Japan, and Italy known for their pollution with PFAS, and enrichment was conducted on the media supplemented with ppm values of PFOA (Beskoski et al., 2018). Microbial communities were used as inoculum in the PFOA biodegradation study.

Danas se u životnoj sredini mogu pronaći brojna hemijska jedinjenja koja je stvorio čovek u svojim laboratorijama. Ideja vodilja sredinom dvadesetog veka je bila kreirati jedinjenja kvalitetnih osobina koja će dugo imati upotrebnu vrednost a samim tim i dugo trajati. Neka od tih jedinjenja su danas prepoznata i kao „večne hemikalije”. Per- i polifluorovana jedinjenja (PFAS) su grupa sintetičkih hemijskih jedinjenja koja poseduju C- F, najjaču kovalentnu vezu. Zbog hemijske strukture koja im omogućava stabilnost na povišenim temperaturama, otpornost na niske pH vrednosti kao i visoku površinsku aktivnost, ova jedinjenja su u vidu različitih formulacija već nekoliko decenija našla široku primenu u brojnim potrošačkim proizvodima. Međutim, PFAS su poslednje dve decenije otkriveni u vodi, zemljištu, sedimentu, vazduhu, hrani i uzorcima biote na svim kontinentima, što prepoznato kao rizik za životnu sredinu i zdravlje ljudi. Zbog ovoga su u poslednjoj deceniji intenzivno testirane postojeće tehnologije za sanaciju i remedijaciju poput adsorpcije, filtracije, termalne destrukcije, oksidacije/redukcije kao i pranje zemljišta. Ipak, opisani su i brojni nedostaci ovih tehnologija.

Razvoj hemijske industrije u prošlom veku pozitivno je uticao na životni standard, ali je za sobom ostavio značajne količine toksičnih supstanci u životnoj sredini. Dugotrajne organske zagađujuće supstance (Persistant Organic Pollutants - POPs) su antropogene hemikalije koje se zadržavaju, akumuliraju u lancu ishrane i imaju štetne posledice po zdravlje ljudi i životnu sredinu. Cilj ovog rada je izolovanje bakterijskih sojeva sa zagađenih lokaliteta i njihova potencijalna primena u biodegradaciji perfluorovanih jedinjenja.

U poslednje vreme, bis-(2-hidroksietil)-tereftalat (BHET) se često koristi kao model jedinjenje za identifikovanje novih biokatalizatora za degradaciju polietilen-tereftalat (PET). Stoga, u radu je predstavljeno ispitivanje mehanizma degradacije BHET-a pomoću mikroorganizama.

Cilj ovog rada bio je selektovati mikroorganizme koji mogu da razgrade Bis-(2-hidroksietil)-tereftalat (BHET) kao model jedinjenje za ispitivanje degradacije plastičnog otpada na bazi polietilen tereftalata (PET) i sa visokim prinosom produkuju egzopolisaharide.

Plastika kao izvor zagađenja postaje sve veći globalni problem. Većina plastike je dizajnirana za jednokratnu upotrebu, što dodatno povećava količinu plastičnog otpada. Usled preopterećenja zemlje i voda plastičnim otpadom neophodno je razviti procese koji će omogućiti efikasno uklanjanje plastike iz životne sredine. Kao povoljan metod degradacije PET plastike predlaže se enzimska hidroliza korišćenjem mikroorganizama koji kao izvor ugljenika mogu koristiti PET. Cilj ovog rada je bila identifikacija mikroorganizama koji potencijalno razgrađuju BHET, kao i primena čistih kultura za degradaciju istog.

A series of novel polyurethane network/organoclay nanocomposites (PUN-NCs) with different soft segment contents (30–60 wt%) was prepared by in situ polymerization in solution and characterized. PU network (PUN) was made from poly(dimethylsiloxane)-based macrodiol as the soft segment and 4,4′-methylenediphenyldiisocyanate and hyperbranched polyester of the third pseudo generation as the hard segment. Nanocomposites were obtained by dispersion of organically modified montmorillonite (Cloisite 30B) nanofiller (0.5 wt%). The influence of the soft segment content on the functional properties of PUN-NCs was studied by Fourier transform infrared (FTIR), small-angle and near wide-angle X-ray scattering (SWAXS), thermogravimetric analysis (TGA), dynamic mechanical thermal analyses (DMTA), differential scanning calorimetry (DSC), nanoindentation, atomic force microscopy (AFM), scanning electron microscopy (SEM), and swelling behavior, water absorption and contact angle measurements. The biodegradation process was evaluated using mixed cultures of microorganisms that originated from soil. Mechanically strong PUN-NC materials in the form of films were obtained, pointing to good dispersion and the existence of exfoliated morphology of Cloisite 30B within the PUN matrix, and the nanocomposites with the abovementioned characteristics were obtained as a function of the soft segment content. The decrease of the soft segment content induced a higher degree of phase separated microstructure, increase of Young's modulus, hardness, plasticity, storage modulus, glass transition temperature, surface free energy and swelling ability in tetrahydrofuran, but at the same time, it is responsible for the decrease of crosslinking density and hydrophobicity of PUN-NCs. By choosing adequate soft segment content, the prepared materials can potentially be designed for coating applications, such as top coating materials in environmental conditions.

Metals are widespread in nature and organisms are constantly exposed to them through a variety of sources, therefore, there is a need for microorganisms to have the ability to respond to potentially toxic metals in their environment. One of such metals is chromium (Cr), and the toxicity of Cr is dependent on oxidation state and solubility. Chromate (Cr(VI)) is a powerful oxidizing agent, and is more toxic then Cr (III). The aim of this work was to determine the influence of chromate on the respiration and enzymatic activity of baker’s and brewer’s yeast, Saccharomyces cerevisiae.

Polyurethanes (PUs) are widely used polymers, with specific production able to be aimed at their notable industrial and biomedical applications by carefully changing their ingredients, their ratios and their preparation procedures. The popularity of PU nanocomposites is caused mainly by the simplicity of tuning their functional properties. The choice of nanofillers, for example, clay, graphene oxide, carbon nanotubes, silicon dioxide, nanosilver or nanoferrite is miscellaneous. In this work, PU/clay nanocomposites were prepared by in situ polymerization in the presence of organically modified clay (Cloisite 30B) with clay loading of 0.5 wt.%. We used hyperbranched polyester and 4,4'-methylenediphenyldiisocyanate as hard segment components, while poly(dimethylsiloxane) macrodiol as soft segment. The influence of the soft segment content on the properties of nanocomposites was investigated by swelling behavior, crosslinking density, degree of phase separation, water absorption and contact angle measurements as well as surface free energy determination. FTIR results showed the higher degree of phase separation in nanocomposites as soft segment content decreased. Moreover, the results showed that equilibrium swelling degree of PU nanocomposites decreases, while crosslinking density increases with decreasing soft segment content. Hydrophobicity of the PU nanocomposites increases with increasing soft segment content, due to the hydrophobic character of PDMS. Namely, the surface free energy of nanocomposites films decreases in the range of 39.8 to 28.0 mJ/m2 with increasing soft segment content, confirming good surface hydrophobicity. Therefore, PU nanocomposites could be considered as promising materials suitable for coating applications.

in this study, in situ polymerization procedure in solvent mixture was used for the preparation of thermosetting PU nanocomposites (PUNCs) with different content of soft segment (from 30 to 60 wt%), and with the addition of organomodified montmorillonite clay (Cloisite 30B®) as the nanofiller, in an amount of 0.5 wt.%. The PUNCs were based on poly(dimethylsiloxane) macrodiol (PDMS) that represents soft segment and 4,4′-diphenylmethane diisocyanate (MDI) and hyperbranched polyester (BH-30) which were selected as the hard segment. The PUNCs are marked. so that the last two numbers in title indicate wt.% of soft segment in materials. Namely, the main objective of this study is to analyze the effect of the soft segment content on the morphology of the prepared PU nanocomposite films using atomic force microscopy (AFM), scanning electron microscopy (SEM), and small- and near wide-angle X-Ray scattering (SWAXS) analyses. SEM images of the fractured surfaces were obtained on JEOL JSM-6610LV. AFM analysis was carried out by atomic force microscope (Dimension Icon, Bruker, USA). SWAXS measurements of the PUNCs were performed using SAXS instrument (originally Molecular Metrology, USA, recently considerably upgraded by SAXSLAB, now Xenocs).