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Abstract Vascular tubules in natural leaves form quasi-fractal networks that can be metallized. Traditional metallization techniques for these lignocellulose structures are complex, involving metal sputtering, nanoparticle solutions, or multiple chemical pretreatments. Here we present a novel, facile, and reliable method for metallizing leaf-derived lignocellulose scaffolds using silver microparticles. The method achieves properties on-par with the state-of-the-art, such as broadband optical transmittance of over 80%, sheet resistances below 1 Ω/sq., and a current-carrying capacity exceeding 6 A over a 2.5 × 2.5 cm² quasi-fractal electrode. We also demonstrate copper electrodeposition as a cost-effective approach towards fabricating such conductive, biomimetic quasi-fractals. Additionally, we show that these metallized structures can effectively eliminate pathogenic microorganisms like fecal coliforms and E. coli, which are bacterial indicators of microbiological contamination of water. We finally show that these oligodynamic properties can be significantly enhanced with a small externally applied voltage, indicating the noteworthy potential of such structures for water purification and pollution control.

A continuous population and industrialization growth have enhanced the production of chemical compounds as well as their structural chemical diversification. Unfortunately, they have become an increasing burden for the environmental sustainability and biodiversity. The need for producing and using environmentally friendly products become increasingly evident in the current context of environmental concerns. It is crucial to develop new products and technologies that reduce their overall harmful environmental impact and promote its sustainability. In this study, the citrus peels waste was transformed into a potential antibacterial and antifungal extract by hydrodistillation. The efficacy of orange peels hydro distillation process in obtaining plant extracts was improved by a pre-enzyme-assisted extraction step. Enzymes such as cellulase and pectinase improved the breakdown of cellulose and pectin structures, which led to an increased extraction yield of bioactive compounds and antimicrobial activity.

The SARS-CoV-2 pandemic situation put extreme pressure on the worldwide medical system from medical personnel to medical equipment. The protective face mask became the front line of anti-SARS-CoV-2 prevention methods, used by most of the world population, more than 7 billion people. The massive demand for face masks activated the world market, where countries from different continents increased their mask production and commercialization worldwide. Unfortunately, the focus on face mask production mostly relied on their ability to filter small-size molecules and less on their microbiological sterile status. Since bacterial structural communities could differ between various large populational groups or continents, in this study, we analyzed the microbial quality of face masks received from various countries/continents. There were analyzed the microbiological load of four types of masks, three from China and one from Romania. The bacterial density from masks was analyzed by membrane filtration and swabbing bacterial collection techniques. The results showed the Romanian mask had a smaller bacterial load than the Chinese masks. In addition, the bacterial identification showed a wide range of bacterial strains, quite different between face mask types.

The COVID-19 pandemic was a challenge for the whole world, and it had major secondary effects on humans and environmental health. The viral infection induced, in many situations, secondary bacterial infections, especially enteric infections, by destabilizing the balance of the gastrointestinal microbiota. The large-scale use of antibiotics and biocides for both curative and preventive purposes has resulted in an increase in bacterial resistance, and at the same time, the possibility of pathogenic microorganism multiplication and their dissemination to natural environments. Wastewater is the main vector of fecal microorganisms that favors their dissemination into natural aquatic ecosystems. The present paper aims to analyze the effect of the COVID-19 pandemic on the microbiological quality of wastewater from sewage treatment plants in Romania and its impact on receiving rivers. In order to highlight different and important areas in Romania, three cities from the east, center and west were selected for a microbiological evaluation of their WWTP influents and effluents from the pre-COVID-19 period and during the COVID-19 pandemic peak period, when the COVID-19 pandemic had a direct impact on WWTP microbial compositions. Our study shows that a higher level of contamination with fecal bacteria is linked to a higher COVID-19 incidence. The increased usage of pharmaceutical compounds, in turn, increases the number of resistant bacteria reaching the environment via WWTP effluents.

The wide distribution of bacteria and their highly dynamic activities have a great impact on the aquatic ecosystem. Surface water bodies constitute an important drinking water source that approximatively cover half of the worldwide need. Considering the main health threats, the microbial profile represents the most important indicator on the biology quality of water environments. One of the most important criterion is fecal indicators and in consequence the aim of this study was to monitor the seasonal fecal pollution variability in the surface water of Arges and Dambovita River during 2021. These rivers are part of the Arges-Vedea basin that cover 9% of Romania’s surface and they are located in the proximity of the Bucharest, the capital city of Romania.

The current work focused on the water quality of the Bega and Timis rivers measured by two methods. One of them is the method by which the water was analyzed from a physical-chemical point of view, and the other aimed at quantifying the degree of water pollution by biological methods. In this sense, diatoms were used. In the study, samples of water and diatoms were taken using specific techniques from the Bega and Timis rivers, starting from near the area of their formation until near the border with Serbia. Four sampling points were chosen on the Timis River plus one sampling point on the Surgani River, which is a tributary of the Timis, and six sampling points on the Bega River. The points were chosen specifically, being located downstream of the major sources of pollution. In order to locate the points, information was collected from the studies carried out as part of an extensive monitoring that spanned several years. The abundance and diversity of diatom species were used to calculate the Biological Diatom Index (BDI) and the Saprobity Index (SI). These two indices provide valuable information about organic or heavy metal pollution of water bodies.

Nowadays, progressive field crop practice requires modern, reliable, and cost-efficient methods to monitor crop development and yield. The most common and used biochemical parameter for plant physiology, namely the dynamic processes of growth, metabolism, reproduction, defense and communication, is chlorophyll's content in plant leaves. Our paper aims to compare optical in-situ method with a classical in vitro spectrometric chlorophyll detection method. A comparison between a quick and cost-effective screening method using portable CCM-200 plus (Opti-Science, Inc) and a biochemical chlorophyll extraction method was applied. Two sets of chlorophyll concentration data from terrestrial plants such as marigold (Calendula officinalis) and wheat (Triticum sp.) were reported. Chlorophyll pigments has a non-uniform distribution on the leaves surface, thus the concentration differs a lot at different times of the day, and this makes the optical measurements vary a lot between the same leaves. In this study, a mathematical correlation of the optical chlorophyll content conversion to absolute chlorophyll was carried out considering previous studies. The relationships between the CCM-200 measurements and the values obtained for the total chlorophyll concentration and the chlorophyll a/b ratio suggested a wide range of relationships between the two species.

It has been observed the spread of a growing number of antibiotic resistant bacteria (ARB) outside the clinical setting into the environment. The surface water seems to play an important role in ARB dissemination by being both habitats and transport systems for microorganisms, respectively. The ecological and touristic importance of the Danube Delta make it an European priority for a close observation and monitoring of its freshwater system. The main goal of this paper was to analyze how the St. Gheorghe branch of the Danube Delta microbiological contamination and their antibiotic resistant profile were influenced by climate change, especially the global warming from 2013 up to 2019. The bacterial population’s analyses revealed an indirect proportionality between coliform bacteria density in water and sediment during the time. Bacterial strains resistant to commonly used antibiotics in clinical settings were more and more identified and the strains exhibited high rates of beta-lactam resistance, especially to ampicillin and amoxicillin enriched with clavulanic acid.

The COVID-19 pandemic reshaped the global response to a pandemic, including the way of using chemical compounds such as disinfectants and antibiotics. The large-scale use of antibiotics and disinfectants during the COVID-19 pandemic caused environmental pressure not only due to the chemicals themselves but also due to their effect on bacterial communities, inducing resistance to chemicals and changing the population structure of bacterial communities, especially in aquatic environments. The dissemination of fecal bacteria, including antibiotic-resistant bacteria, and pathogens from hospital wastewater into the environment, via wastewater treatment plants (WWTPs), triggered the premises of a major public health issue. Rivers flowing through cities are natural streams for WWTP discharges, and they directly bear the impact of anthropic activities, disseminating domestic and industrial pollution over large areas. The aim of the present study was to assess the microbiological bacterial structure of municipal and hospital wastewaters as well as their impact on natural streams, covering the pre-to post-COVID-19 pandemic period of time. The results indicated that the COVID-19 pandemic had a direct impact on hospital wastewater microbiological quality and the environment due to an excessive use of antibiotics and disinfectants. In addition, the constant presence of antibacterial compounds increased the rate of bacterial selection and induced population structural changes in the bacterial communities from aquatic systems.

Polycyclic aromatic compounds (PAHs) have been noted to generate a high risk for human health. Their presence and concentration have not been equally distributed in the environment and various anthropic activities favored the environmental presence of specific pollution components. The economic sector of bakery, as well as intensive animal breeding, are well spread worldwide and they represent a priority economic sector due to their direct link to the food industry. In this study, particulate matter (PM) and PAH pollutant compounds were monitored and their presence and concentration were correlated with specific anthropic activities such as bakery and animal husbandry. For the first time, the data analysis established correlations between PM10 or PM2.5 sizes and concentrations with a specific anthropic activity (bakery vs. animal husbandry). PM10 seemed to be more present at sites of animal husbandry activities than bakery ones. The vast majority of high PAH concentrations were detected in industrial sites such as bakeries. Spearman statistical correlation tests of intensive breeding of animals and bakery fields showed a moderate correlation between dimensional fractions of particulate matters, which indicated several emission sources, with different characteristics.

The paper aims to emphasis the specific detection of bacterial strains using enzyme-linked immunosorbent assay. The assay is based on the specific binding of polyclonal antibody anti E.coli tagged with FITC to E.coli and monoclonal antibody anti Ps. aeruginosa tagged with Alexa Fluor 647 tagged to Ps. aeruginosa and on subsequent enzymatic immunological demonstration of the conjugated enzyme. In this experiment the negative control was the Salmonella enterica strain. The two antibodies had no interaction with the negative control, instead they were specific for E . coli and Ps. aeruginosa strains. When both strains were in the same well, the fluorescence intensity given by the presence of E. coli was 2.3 times higher than that given by Ps . aeruginosa, and the intensity of fluorescence decreased if there are both bacterial strains in the wells.

The environment pollution is an important issue influencing on human health and environmental equilibrium. The range of pollutants is very wide due to the industrialization and population growth and the surfactants are one of the most common organic pollutants due to their extensive use and ubiquitous presence from industry to households. Their massive presence in the domestic and industrial wastewater could affect the Wastewater treatment plants by inhibit the activated sludge used in pollutants biodegradation treatment step. This paper aimed to study the inhibition effect of three classes of surfactants (nonionic, anionic and cationic) by measuring of the respiratory activity of microorganisms with the application of the Oxygen Uptake Rate (OUR) test. This study established that the surfactants can activate or inhibit microorganisms activity, depending on surfactant concentration.

The paper focused on the possible links among pollution, pollution management efficiency including waste management and the propensity of a variety of emerging diseases in our society by answering the question: “How pollution can affect human health?” Environmental pollution is a reality and our planet ecosystem possibilities to face the challenges due to the constant exceeding its resilience are becoming smaller and smaller. The evolution of the climate change indicators like global temperature, global CO2 emissions, oceans acidification and species extinction point out that in a not very long period of time, the planet will not be able to sustain any more the present society’s life style set by the current economic development. Therefore, many warning signals have been issued to change the present behavior in order to reduce significant damages done to the environment and on human health with serious implications on the dysregulation of our immunity and the onset of a plethora of diseases. In this respect, the present paper reviewed relevant aspects linked to the environmental pollution issues that become part of scientific and public debates presented in specialty literature in recent years emphasizing why the implementation of “One Health” concept is necessary.

In the last decade, the cosmetic industry has experienced a massive development, but there have also been issues related to their influence on the health of the population. The application methods of the cosmetic products could trigger the appearance of the skin infectious, which raise the need for efficient disinfection processes of the cosmetic products. At the present, the economic operators in the field of cosmetics are guided by medical regulations, but, unfortunately there are not standardized procedure for the application and control of disinfection. The aim of this study was to determine an efficient procedure of disinfection for instruments used in the application of cosmetics such as the beauty blender. There were performed two different disinfection procedures, a chemical disinfection using 70% ethanol and a physical disinfection with UV radiation. The influence of foundation on disinfection procedures was also tested. A standardized S. aureus and a S. haemolyticus bacterium from a human abscess were tested and an antibiotic resistance pattern was also analyzed. The disinfection efficiency tests showed that the ethanol solution was effective after 5 minutes, decreasing the S. haemolyticus bacterial density by 50% in the absence of foundation. In the presence of the foundation, this process was no longer efficient, foundation having a possible protection and nutritional role for bacteria. The radiation with UV at 265 nm showed a complete eradication of both bacterial strains after 1 minute, regardless of foundation presence or not. The antibiotic susceptibility tested showed that both strains had the natural penicillin resistance.

An endless list of companies have produced a large amount of pharmaceutical compounds in a year-on-year growth trend. Due to the excessive consumption of these substances and the inappropriate disposal, the environment was contaminated, especially aquatic ecosystems, with quantities of pharmaceuticals (PHACs) so that they have affected the living organisms, leading to decreased biodiversity and ecological degradation. Many studies on PHACs environmental presence and toxic effects were performed, but unfortunately, no limit was establish for discharging into environment, especially into the aquatic systems. The aim of this study was to use the bioluminescence of Aliivibrio fischeri bacteria as an indicator of toxically effect of different PHACs in simulated marine medium. The Microtox® bioassay is based on the PHACs inhibitory effect on the metabolism of bacteria which induced changes in their bacterial bioluminescence. The test organisms were exposed to analgesics and anti-inflammatories such as Diclofenac, Ketoprofen, Naproxen and Ibuprofen. The results showed that based on EC50 values, Naproxen had a very low toxicity but Diclofenac, Ketoprofen and Ibuprofen had a harmful effect on the aquatic organisms.

The paper aims a review of the water quality monitoring and evaluation studies conducted at National R&D Institute for Industrial Ecology over the last ten years, at the level of aquatic ecosystem complexes in the Danube Delta. The paper will include a broad compendium of data including: a data bank of abiotic variables which control the structure and composition of biotic communities; studies of ecological status assessment; methodology development for assessing the bioaccumulation of chemical pollutants (metals) in the biota; ecotoxicological study of surface water and sediment on aquatic organisms (algae, crustaceans, rotifers); studies on the benthic invertebrate species as biological vectors for pathogens; technical / scientific support for 5 national / international project proposals; 19 papers published in international / national journals; 22 papers presented at international / national scientific conferences.

The worldwide population rise corroborated with the raise of the health-care standards have generated an escalation of the antibiotic production and uncontrolled usage. The subsequent effects of this escalation have led to an increase of the antibiotic resistance rates, Romania is in the top of the EU countries regarding the antibiotic resistance rates, and to a continuous presence in the environment, including the aquatic environment. Unfortunately, the present design of the classical WWTPs is not optimized for the efficient removal of antibiotics since these compounds may have highly soluble and polar molecular structures. Instead, antibiotics removal using microorganisms could be an ecofriendly solution to this environmental issue, as long as their antibiotic degradation structures are not more toxic than the antibiotic itself. In the present review, we focus on the environmental presence and biodegradation of the most commonly used antibiotics as well as on their biodegradation, based on bacterial model, monitored by mass-spectrometric methods.

The market expansion due to globalization generated more anthropogenic contaminants, enhancing their negative impact on the environment. In order to prevent and balanced their negative effect, more rapid, sensitive and eco-friendly ecotoxicological studies as risk assessments were developed. Each country developed national programs to ensure the research infrastructure for implementation and development of new testing methodologies, generating new experimental data transferable to governmental authorities, economic agents and academia. In this review, we intend to highlighted the progress of Romanian researchers in the last 10 years in the field of ecotoxicology and aquatic risk assessment. The studies focused on aquatic systems as a non-targeted system to the anthropogenic pollutants impact. The implemented methodologies according with international requirements for chemical control like REACH Regulation, Detergents Regulation, Biocide Products Regulation or the Aquatic Risk Assessment Guidelines were presented. The ecotoxicological effects of various contaminants such as detergents, pharmaceuticals, pesticides, biocides or heavy metals and environmental polluted samples (surface water, sediment or sludge) were provided. Overall, the studies presented in our studies have a nationally novelty through the variety of test substances, the complexity of laboratory experiments and data processing. The research work has a continue applicability in industry and for control authorities. New accredited testing services that providing useful information about the chemicals and their impact on the environmental were introduced. In addition, the ecotoxicology studies and their challenges were a great source for professional training like PhD and master studies and for impact published papers.

One cationic surfactant with a wide spectrum of microbiocidal activity is benzethonium chloride (BEC). Despite being widely used, the toxicity data on vertebrate organisms are limited. Therefore, we aimed to evaluate within this study the acute toxicity of BEC on the gills and kidneys of Cyprinus carpio (European carp). An alteration of the antioxidant enzymes activities (glutathione reductase, glutathione peroxidase and glutathione S-transferase) was noticed after 96 h of exposure, along with an elevation of lipid peroxidation and decreased concentration of reduced glutathione, which confirmed that BEC was able to induce toxicity to these tissues. These metabolic effects were correlated with unspecific structural changes observed in gills and kidneys, having moderate degree of severity (such as an increase of melanomacrophages aggregation incidence and cytoplasm vacuolation of goblet cells in collecting tubules) and generally being compatible with life for the exposure time studied. The most severe structural effects were observed in gills after 96 h, noticing a lamellar aneurysm, hemorrhages and lamellar epithelium disruption due to the blood vessels and pillar cells damages and increased blood flow inside the lamellae. By our research we can confirm the utility of biochemical and histological analyses in the fish organs as tools for monitoring the water quality and ecotoxicological potential of chemicals.

Benzenthonium chloride (BEC, Hyamine 1622) is a quaternary ammonium surfactant with cationic properties widely used in cleaning, sanitation, and medical products that can become harmful to humans and also to the environment. This study aimed to evaluate its acute effects on Cyprinus carpio fish in terms of oxidative stress and morphological changes on hepatic tissue in order to show the sub-lethal toxicity of BEC. Fish were exposed to 1 mg/L BEC for 24, 48, and 96 h, and the liver samples were collected. The most significant changes were noticed after 96 h of exposure when the entire antioxidant enzyme system was affected. The activities of catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase decreased by 44%, 31%, 30%, and 45%, respectively, compared to control. Glucose-6-phosphate dehydrogenase activity decreased by 29% after 96 h of control, inducing a reduction of NADPH formation which decreased by half the level of reduced glutathione, the main non-enzymatic antioxidant. These effects correlated with the raised value of lipid peroxidation after 96 h and the morphology changes on hepatic tissue, such as cytoplasmic vacuolization and nuclear hypertrophy that could affect the normal function of the liver. All of these results showed acute toxicity of BEC on C. carpio after 96 h of exposure, causing oxidative stress response at the hepatic level.

Abstract The economic factor of the microalgae harvesting step acts as a barrier to scaling up microalgae-based technology designed for wastewater treatment. In view of that, this study presents an alternative microalgae-bacteria system, which is proposed for eliminating the economic obstacle. Instead of the microalgae-bacteria (activated algae) flocs, the study aimed to develop activated algae granules comprising the microalgae Chlorella sp. as a target species. The presence of the filamentous microalgae (Phormidium sp.) was necessary for the occurrence of the granulation processes. A progressive decrease in frequency of the free Chlorella sp. cells was achieved once with the development of the activated algae granules as a result of the target microalgae being captured in the dense and tangled network of filaments. The mature activated algae granules ranged between 600 and 2,000 µm, and were characterized by a compact structure and significant settling ability (21.6 ± 0.9 m/h). In relation to the main aim of this study, a microalgae recovery efficiency of higher than 99% was achieved only by fast sedimentation of the granules; this performance highlighted the viability of the granular activated algae system for sustaining a microalgae harvesting procedure with neither cost nor energy inputs.