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Diesel has served as a primary source of fuel in transportation, as well as in small-scale energy generation for backup or emergency power supply, for decades (de Witt et al, 2021). Despite the decreasing production of fossil fuels due to global energy transitions, environmental contamination by petroleum derivatives can persist for extended periods (Marigómez, 2014). Consequently, there remains a high demand for improved technologies to clean up contaminated areas [Ossai et al, 2020]. This paper presents a GC/MS study on the biodegradation of hydrocarbon fractions of diesel D2, utilizing indigenous Rhodocuccus sp. isolated from petroleum-contaminated soil. GC-MS analysis was employed to determine the abundances of specific compounds such as n-alkanes, isoprenoids, sesquiterpanes, hopanes, steranes, and aromatic compounds (including trimethyl-naphthalenes, phenanthrene, anthracene, methylphenanthrenes, dibenzothiophene, and methyl-dibenzothiophenes). After 30 days of biodegradation of diesel D2, significant degradation was achieved, with complete degradation of sesquiterpanes and a reduction in the number of n-alkanes lower than C21. Pristane and phytane were almost completely degraded. Additionally, dimethyl-dibenzothiophenes were nearly completely degraded and removed from the system.

Diesel has served as a primary source of fuel in transportation, as well as in small-scale energy generation for backup or emergency power supply, for decades (de Witt et al, 2021). Despite the decreasing production of fossil fuels due to global energy transitions, environmental contamination by petroleum derivatives can persist for extended periods (Marigómez, 2014). Consequently, there remains a high demand for improved technologies to clean up contaminated areas [Ossai et al, 2020]. This paper presents a GC/MS study on the biodegradation of hydrocarbon fractions of diesel D2, utilizing indigenous Rhodocuccus sp. isolated from petroleum-contaminated soil. GC-MS analysis was employed to determine the abundances of specific compounds such as n-alkanes, isoprenoids, sesquiterpanes, hopanes, steranes, and aromatic compounds (including trimethyl-naphthalenes, phenanthrene, anthracene, methylphenanthrenes, dibenzothiophene, and methyl-dibenzothiophenes). After 30 days of biodegradation of diesel D2, significant degradation was achieved, with complete degradation of sesquiterpanes and a reduction in the number of n-alkanes lower than C21. Pristane and phytane were almost completely degraded. Additionally, dimethyl-dibenzothiophenes were nearly completely degraded and removed from the system.

Lindane is an organochlorine compound that belongs to the group of hexachlorocyclohexane (HCH). HCH is a group of compounds consisting of cyclohexane having one chlorine and one hydrogen attached to each carbon, their common chemical formula is C6H6Cl6 (Zdravkoski et al., 2004). The estimated amount of lindane used globally for agricultural purposes, livestock, forestry, human health in the period from 1950 to 2000 is about 600,000 tons. Since the 1990s, research has begun on possible ways to remove lindane. In addition to more traditional methods such as storage or incineration, catalysts have been discovered that enable faster photodegradation such as TiO2 or mixtures of TiO2 with other metal oxides like CeO2 (Radić et al., 2022). Meanwhile, the microbial breakdown of lindane contamination is becoming more and more recognized as an economical and environmentally friendly alternative to traditional treatment methods (Bhatt et al, 2019).

Lindane is an organochlorine compound that belongs to the group of hexachlorocyclohexane (HCH). HCH is a group of compounds consisting of cyclohexane having one chlorine and one hydrogen attached to each carbon, their common chemical formula is C6H6Cl6 (Zdravkoski et al., 2004). The estimated amount of lindane used globally for agricultural purposes, livestock, forestry, human health in the period from 1950 to 2000 is about 600,000 tons. Since the 1990s, research has begun on possible ways to remove lindane. In addition to more traditional methods such as storage or incineration, catalysts have been discovered that enable faster photodegradation such as TiO2 or mixtures of TiO2 with other metal oxides like CeO2 (Radić et al., 2022). Meanwhile, the microbial breakdown of lindane contamination is becoming more and more recognized as an economical and environmentally friendly alternative to traditional treatment methods (Bhatt et al, 2019).

Table S1. The numbers of microorganisms recovered (CFU g–1) at the start and after bioremediation. Table S2. Percentages of cobalt and molybdenum in different forms, sequentially extracted from the samples, and calculated as the percentage of total metal determined by the melting procedure. Table S3. Amount of cobalt and molybdenum (g kg–1 ) determined by the Melish procedure and by leaching.

Environmental context: Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents. Rationale: Bioremediation harnesses microorganisms’ diverse metabolic abilities to detoxify and eliminate pollutants, particularly hydrocarbon-based ones such as oil. This natural biodegradation process performed by microorganisms is a cost-effective method for environmental cleanup compared to other remediation technologies. Methodology: In this study, we examined the fate of heavy metals, cobalt and molybdenum, by the analysis of the basic chemical parameters of other sample components, such as n-hexane extractable substances and total petroleum hydrocarbons. The metal content was determined using inductively coupled plasma–optical emission spectrometry (ICP-OES). Exchangeable (loosely bound to the surface of particles and due to its high mobility and availability is crucial for understanding the potential immediate impact of metal contamination) and more stable fractions of the metal and the metal forms were determined using a sequential extraction method. The phase composition of the samples was determined by X-ray diffraction. Results: In our microbiological analysis, we isolated various cultures from a consortium of microorganisms. Basic chemical analysis indicators, such as n-hexane extractable substances, total petroleum hydrocarbons and humic acids, reflected robust microbiological activity. During the study, metals in exchangeable form decreased and those in more stable forms increased. Discussion: The sequential extraction of cobalt and m

Freshwater lakes have been heavily altered by multiple stressors for decades, including a wide range of harmful human activities. Similarly, it is estimated that most of continental saline lakes will have undergone changes in their functioning by 2025. In the European Water Framework Directive (WFD), the ecological status assessment of lakes is based on the survey of key communities (i.e., Biological Quality Elements, BQEs). Due to its ecological features, phytoplankton is one of the key BQEs required by the WFD. In current assessments, phytoplankton is studied using a standardised microscopy approach. The advent of methods based on molecular techniques (e.g., eDNA metabarcoding) provides an alternative to overcome issues associated with microscopy-based assessment. The aim of our study was to compare phytoplankton data obtained by microscopy approach with eDNA metabarcoding based on the 23S RNA marker gene. Water was sampled in eight sites: four sites in Savsko lake (urban freshwater lake) and four sites in Plava Banja (saline clay pit pond) during spring, summer, and autumn 2023. The water quality analyses showed that nutrient concentrations (especially total nitrogen), chlorophyl a and conductivity were several times lower in the freshwater lake than in the saline lake. The very high total dissolved mineral content in Plava Banja had a substantial impact on the phytoplankton composition The results of lake species inventories obtained using both approaches will be presented. Particular attention will be paid to the level of congruence between the fl oristic lists.

Charophyte algae have long been used for the ecological status assessment of lakes. Traditional fieldwork and species determination are, however, time-consuming and expensive. In the BIOLAWEB project, we aim to use environmental DNA (eDNA) for metabarcoding of Chara sp. in the water samples from selected lakes, and use this information to develop new or improve existing indices for the ecological status assessment of lakes. Ecological status assessment of lakes is important to safeguard biodiversity, and to ensure that lakes are in good enough status to safely be used for, among others, drinking water production, and recreation. Charophytes are benthic algae which are sensitive to changes in water quality and therefore are important indicators for ecological status. The use of eDNA is an approach that can be used to quickly detect the presence of different species in a lake, including species that are easily overlooked with more traditional, time-consuming methods. The use of eDNA for ecological status assessment is, therefore, a new and promising field of study. Here we present preliminary results of charophyte investigations in four lakes in Serbia, two freshwater and two saline lakes, in three seasons. Besides traditional sampling of charophytes, water samples were filtered for eDNA, aiming to generate new knowledge on the use of DNA metabarcoding for the detection of charophyte algae and for improving indices for ecological status assessment.

Environmental contextMitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents.RationaleBioremediation harnesses microorganisms’ diverse metabolic abilities to detoxify and eliminate pollutants, particularly hydrocarbon-based ones such as oil. This natural biodegradation process performed by microorganisms is a cost-effective method for environmental cleanup compared to other remediation technologies.MethodologyIn this study, we examined the fate of heavy metals, cobalt and molybdenum, by the analysis of the basic chemical parameters of other sample components, such as n-hexane extractable substances and total petroleum hydrocarbons. The metal content was determined using inductively coupled plasma–optical emission spectrometry (ICP-OES). Exchangeable (loosely bound to the surface of particles and due to its high mobility and availability is crucial for understanding the potential immediate impact of metal contamination) and more stable fractions of the metal and the metal forms were determined using a sequential extraction method. The phase composition of the samples was determined by X-ray diffraction.ResultsIn our microbiological analysis, we isolated various cultures from a consortium of microorganisms. Basic chemical analysis indicators, such as n-hexane extractable substances, total petroleum hydrocarbons and humic acids, reflected robust microbiological activity. During the study, metals in exchangeable form decreased and those in more stable forms increased.DiscussionThe sequential extraction of cobalt and molybdenum reve

he contamination of the water bodies by diesel oil (DO) and its water-soluble fraction (WSF) represents one of the most challenging tasks in the management of polluted water streams. This paper contains data related to the synthesis and characteristics of the plum stone biochar material (PmS-B), which was made from waste plum stones (PmS), along with its possible application in the sorption of the WSF of DO from contaminated water. Techniques applied in sample characterisation and comparisons were: Elemental Organic Analysis (EOA), Scanning Electron Microscopy−Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR), pH (pHsus) and point of zero charge (pHpzc). In order to increase the overall efficiency of the removal process, sorption and bioremediation were subsequently combined. Firstly, PmS-B was used as a sorbent of WSF, and then the remaining solution was additionally treated with a specific consortium of microorganisms. After the first treatment phase, the initial concentration of diesel WSF was reduced by more than 90%, where most of the aromatic components of DO were removed by sorption. The sorption equilibrium results were best fitted by the Sips isotherm model, where the maximum sorption capacity was found to be 40.72 mg/g. The rest of the hydrocarbon components that remained in the solution were further subjected to the biodegradation process by a consortium of microorganisms. Microbial degradation lasted 19 days and reduced the total diesel WSF concentration to 0.46 mg/L. In order to confirm the non-toxicity of the water sample after this two-stage treatment, eco-toxicity tests based on a microbial biosensor (Aliivibrio fischeri) were applied, confirming the high efficiency of the proposed method.

Project "Boosting Institute of Chemistry, Technology and Metallurgy in Water Biomonitoring" (BIOLAWEB) aims to strengthen the research and innovation capacity of the Institute of Chemistry, Technology and Metallurgy, National Institute of the Republic of Serbia, University of Belgrade (UB-ICTM) in biodiversity assessment and biomonitoring. UB-ICTM researchers made a noticeable contribution to the study of biodiversity, community ecology, and conservation of water bodies in South-Eastern Europe. However, a knowledge on index development and intercalibration following the EU standards for lakes and watercourse monitoring is still lacking in this geographic region. Similarly, there is a knowledge gap in DNA-based ecological status assessment in SEE.

Napredak u molekularnoj biologiji doveo je do snažnog razvoja molekularnih metoda u biomonitoringu. Metabarkoding je porcedura zasnovana na upotrebi DNK molekula koja može da dopuni ili čak potpuno zameni klasičan biomonitoring u skorijoj budućnosti. Sproveli smo istraživanje fitoplanktonske zajednice, važnog biološkog parametra kvaliteta, u Markovačkom jezeru sa ciljem da uporedimo tradicionalni i molekularni pristup u biomonitoringu. Ukupno smo pronašli 105 sekvenci algi i cijanobakterija, ali usled nepotpunosti baze, lista taksona dobijena metabarkodingom je nepotpuna. Iako se rezultati metabarkodinga trenutno ne mogu koristiti za procenu ekološkog statusa u Republici Srbiji, primena molekularnog pristupa u biomonitoringu je obećavajuća., The advancement in molecular biology resultet in development of molecular methods in biomonitoring. Metabarcoding is a DNA based procedure that can supplement or even replace classical biomonitoring in the near future. We conducted a study of phytoplankton, an importtant biological quality element, in Markovačko lake aiming to compare morphological and metabacoding approach in biomonitoring. In total, 105 sequences were obtained, but due to the incompletness of the reference library the metabarcoding taxonomic list was not comprehensive. Although, the metabarcoding results can not be currently used for ecological status assessment in the Republic of Serbia, its application in biomonitoring is promissing.

Growing industrialization and non-renewable resource depletion have a huge impact on alternative clean up technologies development, inducing investigation of the renewable, low-cost waste materials. Recently, lignocellulosic waste biomass, generated at a large scale by different industries, appeared as an attractive feedstock worldwide, due to its abundance, availability, multi-functionality and low cost. Since the fruits production has increasing trend all over the world, generation of lignocellulosic waste such as fruit stones (that represent approximately 1/5 of the total fruit mass) became a great environmental threat. In order to minimize negative impact on the environment, avoid greenhouse gasses emissions and help in resource depletion by its renewable nature, it is necessary to explore its performances regarding its wide application potential. Thermo-chemical conversion of lignocellulosic biomass in oxygen limited conditions, in order to get biochar, has received a lot of attention recently. The biochar production requires lower energy inputs and less expensive technology compared to activated carbon (estimation is that production cost of activated carbon are six times higher than biochar costs). In this paper, waste peach stones biomass was effectively converted into biochar at 500 °C under inert (Ar) atmosphere. Pyrolysis was performed in Nabertherm 1300 muffle furnace for residence time of 1.5 h, with a heating rate of 10 °C/min, while Ar was circulated through the sample at a rate of 100 mL/min. The raw biomass (PS) and obtained biochar (PS-B) with particle size 0.1 mm < dp < 0.5 mm, were characterized by Scanning Electron Microscopy (SEM), Fourier transform infrared spectrometry (FTIR) and Raman spectrometry to understand physicochemical changes which have been occurred after pyrolysis. SEM analysis revealed the increased surface area due to the visible augmentation of pores and roughness. FTIR analysis showed that many bands present in native biomass c

Freeze storage and pasteurization of human milk are common treatments in milk banks. Thermal treatment changes the quality of milk for preterm infants’ nutrition, and the aim of this paper was to examine the nutritional profile and antioxidant potential of preterm human milk after storage and pasteurization, and also after supplementation with fortifier. The effects of storage processes were estimated on mature preterm milk of 30 breastfeeding women. Total proteins, lipids and lactose were determined after thermal processing and supplementation of mature preterm milk with fortifier. The antioxidant capacity was determined using the ferric reducing antioxidant potential method and lipid peroxidation inhibition assay. Protein concentration decreased after frozen storage and pasteurization (p<0.05). Pasteurization further reduced the lipid concentration after freezing. The ferric reducing antioxidant potential decreased after thermal treatments (p<0.05). Supplementation of mature milk with fortifier increased the concentration of proteins, lipids and lactose. Our findings demonstrated that storage and pasteurization processes affect the basic nutritional composition and antioxidant capacity of preterm human milk. In order to ensure adequate nutrition for preterm infants with preterm human milk, supplementation, especially with high concentrations of proteins and lipids, is necessary after thermal treatments.

Background and objectives: Human milk is the golden standard in infant nutrition. A very important segment of nutritional support for premature children is milk banks. In milk banks, during the process of storage and pasteurization, the characteristics of milk change, and consequently, its quality changes as well. Current electrochemical techniques (green analytical chemistry) can be used to determine the quality of milk regarding its total antioxidant capacity (TAC). Methods: The application of various electrochemical methods, such as differential pulse voltammetry, cyclic voltammetry, polarography, or potentiometry, enables monitoring of the quality and redox capacity of human milk and infant food. Changes in the TAC of human milk were examined after thermal treatments, which are commonly used in milk banks, as well as after supplementation with a fortifier. Results: The results obtained using electrochemical methods were compared to the most commonly used spectrophotometric methods for monitoring total antioxidant capacity. The obtained results showed that electrochemical methods can overcome the limitations of spectrophotometric methods, such as lower sensitivity, slower reaction and insensitivity at higher antioxidant concentrations. Cyclic and differential pulse voltammetry methods can be successfully applied as fast methods for testing milk quality in milk banks and clinical studies. Conclusion: The tested electrochemical methods are fast, cheap, and reliable in determining TAC since they are based on direct measurement of electron-donating components of milk and enable the quantitative determination of TAC in human milk and infant food. They are very important for routine and daily determinations of TAC in infant food, as well as for the control of milk freshness, especially after using fortifiers in neonatal units.

The aim of this study was to investigate the environmental risk from the gasoline range volatile organic contaminants in the Sava river aquifer. The investigated area is located in New Belgrade, in the vicinity of the largest heating plant in Belgrade, the capital of Serbia. Our previous research on the oil pollutants in the groundwater at this locality was focused on the origin and spatial distribution of these contaminants, and estimation of potential human health risks from exposure to these compounds. [1] The purpose of our present study is a Tier I Environmental risk assessment in this part of the aquifer. Groundwater samples were collected from 28 hydrogeological boreholes. Preliminary analyses of the organic compounds extracted from the groundwater samples were conducted by gas chromatography with flame ionization detection (GC-FID), and by gas chromatography – mass spectrometry (GC-MS). Volatile organic compounds (VOCs) were analyzed and identified by headspace gas chromatography – mass spectrometry. Chemicals of concern were quantified by headspace gas chromatography with flame ionization detection (HS-GC-FID). In the groundwater samples analyzed, the most frequently detected VOCs were from the group of the gasoline range organics. Concentrations of the individual VOCs ranged from below detection limits to 5.2 mg/L. For each of the compounds quantified, the Risk Quotient (RQ) was calculated as the ratio of the measured concentration of that compound in the groundwater sample and the lowest Predicted Non-Effect Concentration for freshwater aquatic organisms (PNEC). The PNEC values were adopted from the European chemicals agency’s (ECHA) Registration Dossier database. [2] At some of the sampling points, the detected concentrations of VOCs were higher than that of the PNEC values with resulting RQ > 1. Considering the fact that the VOC compounds analyzed were present as mixtures, the mixture RQ was calculated (as a sum of the individual RQs) for each sampling

Refinery wastes generated in conventional crude oil refining processes, or in accidental situations, are complex substrates for treatment and disposal. Petroleum desulphurisation catalysts can also be hazardous refinery waste. They contain various metals, such as cobalt, molybdenum, nickel and tungsten. In this paper, three petroleum refiner’s spent desulphurisation catalysts were investigated. These catalysts were not suitable for recycling and, therefore, were classified as hazardous waste. They were chemically characterised, including phase composition and their effect on a consortium of microorganisms used in the process of bioremediation. Catalysts contained up to 2.26 g kg−1 of total petroleum hydrocarbons, up to 56.7 g kg−1 of iron, 18.6 g kg−1 of molybdenum, and less than 0.1 mg kg−1 each of cobalt and nickel. These obtained results show that bioremediation of such waste is possible.

U ovom radu je ispitivano kombinovanje adsorpcije i bioremedijacije u postupku prečišćavanja voda kontaminiranih dizelom. Prva faza je ispitivanje adsorpcije dizela na biouglju, dobijenom pirolizom koštica šljive. Druga faza je biorazgradnja dizela zaostalog u rastvoru nakon adsorpcije. Oba procesa podržavaju koncept održivog razvoja, kome je imperativ obnovljivost, efikasnost i ekološka prihvatljivost.

Cilj našeg eksperimenta je bio da ispita potencijal Acidithiobacillus ferrooxidans za ekstrakciju cinka iz fotacionog koncentrata polimetalične rude ležišta Rudnik (Srbija).

Aktivnost mikroorganizama je direktno povezana sa njihovim disanjem. U prisustvu velikih količina biodostupne organske supstance, brzina disanja mikroorganizama je veća. Praćenje disanja je postalo bitan parametar u raznim procesima biodegradacije otpadne supstance. Stoga, cilj ovog rada obuhvata praćenje ćelijskog disanja pomoću Micro-Oxymax respirometra, kako bi se dobio bolji uvid u prisustvo dostupne organske supstance u upotrebljenom rečnom sedimentu za generisanje električne energije pomoću MFC

Polychlorinated biphenyls (PCBs) are a group of contaminants characterized by their persistence, long-range transport, biomagnification in food chains and bioaccumulation in humans and wildlife. They have been shown to cause cancer in animals as well as a number of serious non-cancer health effects such as effects on the immune, reproductive and endocrine system and other health effects. The international community has responded to the threat from persisting organic pollutants (POPs), including PCBs, by negotiating a global treaty, the Stockholm Convention on POPs, with the objective of protecting human health and the environment from POPs.

Reserves of rich ore, from which it is technologically possible and economically feasible to obtain metals, mainly by pyrometallurgical processes, are reducing from year to year. At the same time, intensive, world-wide development of technology is causing higher metal consumption, which has resulted in multiple increases of metal prices in recent years. Study of new procedures for usage of low-grade metal ores (e.g. Cu and Zn), while also respecting rigorous environmental regulations, are considered current problems of extractive metallurgy in developed countries. Some of these ores are polymetallic ores. Therefore, increasing efforts are being made to develop new hydrometallurgical and biohydrometallurgical procedures that are more selective than conventional ones and which would enable successful processing of this kind of raw material. [1] The aim of this study was to investigate the possibility of applying Acidithiobacillus sp. B2 to obtain copper, zinc and gold from a polymetallic ore flotation concentrate. The study was designed in two phases.