Facilely tuning the intrinsic catalytic sites of the spinel oxide for peroxymonosulfate activation: From fundamental investigation to pilot-scale demonstration.

Heterogeneous peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) have shown a great potential for pollutant degradation, but their feasibility for large-scale water treatment application has not been demonstrated. Herein, we develop a facile coprecipitation method for the scalable production (∼10 kg) of the Cu-Fe-Mn spinel oxide (CuFeMnO). Such a catalyst has rich oxygen vacancies and symmetry-breaking sites, which endorse it with a superior PMS-catalytic capacity. We find that the working reactive species and their contributions are highly dependent on the properties of target organic pollutants. For the organics with electron-donating group (e.g., -OH), high-valent metal species are mainly responsible for the pollutant degradation, whereas for the organics with electron-withdrawing group (e.g., -COOH and -NO2), hydroxyl radical (•OH) as the secondary oxidant also plays an important role. We demonstrate that the CuFeMnO-PMS system is able to achieve efficient and stable removal of the pollutants in the secondary effluent from a municipal wastewater plant at both bench and pilot scales. Moreover, we explore the application prospect of this PMS-based AOP process for large-scale wastewater treatment. This work describes an opportunity to scalably prepare robust spinel oxide catalysts for water purification and is beneficial to the practical applications of the heterogeneous PMS-AOPs.

Proteomic profiling of antibiotic-resistant Escherichia coli GW-AmxH19 isolated from hospital wastewater treated with physical plasma.

Microorganisms which are resistant to antibiotics are a global threat to the health of humans and animals. Wastewater treatment plants are known hotspots for the dissemination of antibiotic resistances. Therefore, novel methods for the inactivation of pathogens, and in particular antibiotic-resistant microorganisms (ARM), are of increasing interest. An especially promising method could be a water treatment by physical plasma which provides charged particles, electric fields, UV-radiation, and reactive species. The latter are foremost responsible for the antimicrobial properties of plasma. Thus, with plasma it might be possible to reduce the amount of ARM and to establish this technology as additional treatment stage for wastewater remediation. However, the impact of plasma on microorganisms beyond a mere inactivation was analyzed in more detail by a proteomic approach. Therefore, Escherichia coli GW-AmxH19, isolated from hospital wastewater in Germany, was used. The bacterial solution was treated by a plasma discharge ignited between each of four pins and the liquid surface. The growth of E. coli and the pH-value decreased during plasma treatment in comparison with the untreated control. Proteome and antibiotic resistance profile were analyzed. Concentrations of nitrite and nitrate were determined as long-lived indicative products of a transient chemistry associated with reactive nitrogen species (RNS). Conversely, hydrogen peroxide served as indicator for reactive oxygen species (ROS). Proteome analyses revealed an oxidative stress response as a result of plasma-generated RNS and ROS as well as a pH-balancing reaction as key responses to plasma treatment. Both, the generation of reactive species and a decreased pH-value is characteristic for plasma-treated solutions. The plasma-mediated changes of the proteome are discussed also in comparison with the Gram-positive bacterium Bacillus subtilis. Furthermore, no effect of the plasma treatment, on the antibiotic resistance of E. coli, was determined under the chosen conditions. The knowledge about the physiological changes of ARM in response to plasma is of fundamental interest to understand the molecular basis for the inactivation. This will be important for the further development and implementation of plasma in wastewater remediation.

Kinetic and thermodynamic analysis of alizarin Red S biosorption by Alhagi maurorum: a sustainable approach for water treatment.

Synthetic dyes, such as Alizarin Red S, contribute significantly to environmental pollution. This study investigates the biosorption potential of Alhagi maurorum biosorbent for the removal of Alizarin Red S (ARS) from aqueous solutions. Fourier transform infrared spectroscopy (FTIR) was used to analyze the biosorbent's adsorption sites. Various parameters were optimized to maximize dye adsorption. An optimal removal efficiency of 82.26% was attained by employing 0.9 g of biosorbent with a 25 ppm dye concentration at pH 6 and 60 °C over 30 min. The data were modeled using various isothermal and kinetic models to understand the adsorption behavior. Thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic. The pseudo-second-order kinetic model best described the data, indicating chemisorption as the rate-limiting step. The data matched best to the Langmuir model, indicating that the adsorption occurs as a monolayer on uniform surfaces with a finite number of binding sites. The model showed a strong correlation (R² = 0.991) and a maximum adsorption capacity (qmax) of 8.203 mg/g. Principal component analysis (PCA) identified temperature as the dominant factor, with the primary component, PC1 capturing 100% of its effect. The mechanisms involved in ARS biosorption on A. maurorum include electrostatic interactions, hydrogen bonding, hydrophobic interactions, dipole-dipole interactions, and π-π stacking. Alhagi maurorum showed promising potential for biosorbing toxic dyes from contaminated water, suggesting further investigation for practical applications.

Carbon Dots-Embedded Silica Tubes: An Excitation-Independent Yellow-Emitting Turn-On Probe for Simultaneous Detection and Removal of Inorganic Arsenic with In Vivo Tracking in Living Organisms.

The environmental monitoring and remediation of highly toxic inorganic arsenic species in natural water are needed for the benefit of the ecosystem. Current studies on arsenic detection and removal often employ separate materials, which exhibit blue luminescence with fluorescence quenching, making them unsuitable for biological and environmental samples. In this study, carbon dot-embedded mesoporous silica tubes functionalized with melamine are synthesized to address these limitations and enable specific and turn-on probing of inorganic arsenic. The newly synthesized material demonstrates excitation-independent yellow luminescence and can effectively detect both As (III) and As (V) at low detection limits (11 × 10-9 m, 11.2 × 10-9 m), well below the prescribed threshold limits in drinking water. It also exhibits a high adsorption capacity (≈125, 159 mg g-1 ) with fast kinetics. The material's applicability in environmental samples is validated through the successful quantification of arsenic in real samples with satisfactory recoveries. Moreover, the material shows recyclability for reuse, as demonstrated by its arsenic adsorption and desorption for several cycles under basic conditions. Additionally, the material's capability for monitoring arsenic in a biological sample (Artemia salina) is demonstrated through fluorescence imaging. The encouraging outcomes underscore the material's potential use in monitoring and mitigating arsenic in aqueous systems.

Methamphetamine Removal from Aquatic Environments by Magnetic Microrobots with Cyclodextrin Chiral Recognition Elements.

The growing consumption of drugs of abuse together with the inefficiency of the current wastewater treatment plants toward their presence has resulted in an emergent class of pollutants. Thus, the development of alternative approaches to remediate this environmental threat is urgently needed. Microrobots, combining autonomous motion with great tunability for the development of specific tasks, have turned into promising candidates to take on the challenge. Here, hybrid urchin-like hematite (α-Fe2O3) microparticles carrying magnetite (Fe3O4) nanoparticles and surface functionalization with organic ß-cyclodextrin (CD) molecules are prepared with the aim of on-the-fly encapsulation of illicit drugs into the linked CD cavities of moving microrobots. The resulting mag-CD microrobots are tested against methamphetamine (MA), proving their ability for the removal of this psychoactive substance. A dramatically enhanced capture of MA from water with active magnetically powered microrobots when compared with static passive CD-modified particles is demonstrated. This work shows the advantages of enhanced mass transfer provided by the externally controlled magnetic navigation in microrobots that together with the versatility of their design is an efficient strategy to clean polluted waters.

Accounting for the microbial assembly of each process in wastewater treatment plants (WWTPs): study of four WWTPs receiving similar influent streams.

We evaluated a unique model in which four full-scale wastewater treatment plants (WWTPs) with the same treatment schematic and fed with similar influent wastewater were tracked over an 8-month period to determine whether the community assembly would differ in the activated sludge (AS) and sand filtration (SF) stages. For each WWTP, AS and SF achieved an average of 1-log10 (90%) and <0.02-log10 (5%) reduction of total cells, respectively. Despite the removal of cells, both AS and SF had a higher alpha and beta diversity compared to the influent microbial community. Using the Sloan neutral model, it was observed that AS and SF were individually dominated by different assembly processes. Specifically, microorganisms from influent to AS were predominantly determined by the selective niche process for all WWTPs, while the microbial community in the SF was relatively favored by a stochastic, random migration process, except two WWTPs. AS also contributed more to the final effluent microbial community compared with the SF. Given that each WWTP operates the AS independently and that there is a niche selection process driven mainly by the chemical oxygen demand concentration, operational taxonomic units unique to each of the WWTPs were also identified. The findings from this study indicate that each WWTP has its distinct microbial signature and could be used for source-tracking purposes.IMPORTANCEThis study provided a novel concept that microorganisms follow a niche assembly in the activated sludge (AS) tank and that the AS contributed more than the sand filtration process toward the final microbial signature that is unique to each treatment plant. This observation highlights the importance of understanding the microbial community selected by the AS stage, which could contribute toward source-tracking the effluent from different wastewater treatment plants.

Impact of operational conditions on drinking water biofilm dynamics and coliform invasion potential.

Biofilms within drinking water distribution systems serve as a habitat for drinking water microorganisms. However, biofilms can negatively impact drinking water quality by causing water discoloration and deterioration and can be a reservoir for unwanted microorganisms. In this study, we investigated whether indicator organisms for drinking water quality, such as coliforms, can settle in mature drinking water biofilms. Therefore, a biofilm monitor consisting of glass rings was used to grow and sample drinking water biofilms. Two mature drinking water biofilms were characterized by flow cytometry, ATP measurements, confocal laser scanning microscopy, and 16S rRNA sequencing. Biofilms developed under treated chlorinated surface water supply exhibited lower cell densities in comparison with biofilms resulting from treated groundwater. Overall, the phenotypic as well as the genotypic characteristics were significantly different between both biofilms. In addition, the response of the biofilm microbiome and possible biofilm detachment after minor water quality changes were investigated. Limited changes in pH and free chlorine addition, to simulate operational changes that are relevant for practice, were evaluated. It was shown that both biofilms remained resilient. Finally, mature biofilms were prone to invasion of the coliform, Serratia fonticola. After spiking low concentrations (i.e., ±100 cells/100 mL) of the coliform to the corresponding bulk water samples, the coliforms were able to attach and get established within the mature biofilms. These outcomes emphasize the need for continued research on biofilm detachment and its implications for water contamination in distribution networks. IMPORTANCE: The revelation that even low concentrations of coliforms can infiltrate into mature drinking water biofilms highlights a potential public health concern. Nowadays, the measurement of coliform bacteria is used as an indicator for fecal contamination and to control the effectiveness of disinfection processes and the cleanliness and integrity of distribution systems. In Flanders (Belgium), 533 out of 18,840 measurements exceeded the established norm for the coliform indicator parameter in 2021; however, the source of microbial contamination is mostly unknown. Here, we showed that mature biofilms, are susceptible to invasion of Serratia fonticola. These findings emphasize the importance of understanding and managing biofilms in drinking water distribution systems, not only for their potential to influence water quality, but also for their role in harboring and potentially disseminating pathogens. Further research into biofilm detachment, long-term responses to operational changes, and pathogen persistence within biofilms is crucial to inform strategies for safeguarding drinking water quality.

Source-to-tap investigation of the occurrence of nontuberculous mycobacteria in a full-scale chloraminated drinking water system.

Nontuberculous mycobacteria (NTM) in drinking water are a significant public health concern. However, an incomplete understanding of the factors that influence the occurrence of NTM in drinking water limits our ability to characterize risk and prevent infection. This study sought to evaluate the influence of season and water treatment, distribution, and stagnation on NTM in drinking water. Samples were collected source-to-tap in a full-scale, chloraminated drinking water system approximately monthly from December 2019 to November 2020. NTM were characterized using culture-dependent (plate culture with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry [MALDI-TOF MS] isolate analysis) and culture-independent methods (quantitative PCR and genome-resolved metagenomics). Sampling locations included source waters, three locations within the treatment plant, and five buildings receiving water from the distribution system. Building plumbing samples consisted of first draw, 5-min flush, and full flush cold-water samples. As the study took place during the COVID-19 pandemic, the influence of reduced water usage in three of the five buildings was also investigated. The highest NTM densities source-to-tap were found in the summer first draw building water samples (107 gene copies/L), which also had the lowest monochloramine concentrations. Flushing was found to be effective for reducing NTM and restoring disinfectant residuals, though flush times necessary to improve water quality varied by building. Clinically relevant NTM species, including Mycobacterium avium, were recovered via plate culture, with increased occurrence observed in buildings with higher water age. Four of five NTM metagenome-assembled genomes were identified to the species level and matched identified isolates.IMPORTANCENTM infections are increasing in prevalence, difficult to treat, and associated with high morbidity and mortality rates. Our lack of understanding of the factors that influence NTM occurrence in drinking water limits our ability to prevent infections, accurately characterize risk, and focus remediation efforts. In this study, we comprehensively evaluated NTM in a full-scale drinking water system, showing that various steps in treatment and distribution influence NTM presence. Stagnant building water contained the highest NTM densities source-to-tap and was associated with low disinfectant residuals. We illustrated the differences in NTM detection and characterization obtained from culture-based and culture-independent methods, highlighting the complementarity between these approaches. We demonstrated that focusing NTM mitigation efforts in building plumbing systems, which have the highest NTM densities source-to-tap, has potential for immediate positive effects. We also identified steps during treatment that increase NTM levels, which provides beneficial information for utilities seeking to reduce NTM in finished water.

Discovery of a new volcanic soil material, "Akahoya," as an adsorbent for bacterial and viral pathogens and its application to environmental purification.

Akahoya is a volcanic soil rich in alumina, primarily deposited in Kyushu, Japan. We have found that Akahoya adsorbs bacteria in the water surrounding cattle grazing areas, suggesting a potential for environmental purification. This study investigated the spectrum of microorganisms adsorbed by Akahoya using a column filled with Akahoya through which a suspension of microorganisms was passed. Shirasu soil, another volcanic soil with a different chemical composition, was used as a control. Akahoya effectively adsorbed a diverse range of microorganisms including Escherichia coli, Campylobacter jejuni, Vibrio parahaemolyticus, Salmonella Enteritidis, Staphylococcus aureus, Clostridium perfringens, spores of Bacillus subtilis and Bacillus anthracis, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), murine norovirus, and avian influenza virus (H3N2), whereas Shirasu soil did not adsorb any of the organisms examined. Moreover, bacteria naturally present in river water, such as aerobic bacteria, total coliforms, and Enterobacteriaceae as indicators of river contamination, as well as E. coli added artificially to sterilized river water, were reduced to below the detection limit (<1 CFU/mL) after being passed through Akahoya. Additionally, the number of viable E. coli continued to decrease after contact with Akahoya for 1 month, suggesting bactericidal effects. Notably, the adsorption of E. coli to Akahoya was influenced by the concentration of phosphate and the pH of the suspension due to the interaction between the surface phosphorylation of organisms and Al2O3, the major chemical component of Akahoya. The present results demonstrate the remarkable ability of Akahoya to remove phosphate and microbes, suggesting that Akahoya could be used for water purification processes.IMPORTANCEAlthough a safe and sufficient water supply is essential for the maintenance of hygienic conditions, a major challenge is to develop a comprehensive effective, sustainable, and cost-effective technological approach for the treatment and purification of contaminated water. In this study, we demonstrated that a novel volcanic soil, Akahoya, which has unlimited availability, is a highly effective adsorbent for a wide range of bacterial and viral pathogens, suggesting its potential as a sustainable resource for this purpose. It was suggested that the adsorption of microorganisms on Akahoya was mediated by phosphate groups present on the surface structures of microorganisms, which bind to the alumina component of Akahoya according to the phosphate concentration and pH of the liquid phase. The present findings highlight the exceptional ability of Akahoya to eliminate or reduce phosphate and microorganisms effectively in water purification processes, thus contributing to the development of efficient and sustainable solutions for addressing water pollution challenges.

Taxonomic variation, plastic degradation, and antibiotic resistance traits of plastisphere communities in the maturation pond of a wastewater treatment plant.

Wastewater treatment facilities can filter out some plastics before they reach the open environment, yet microplastics often persist throughout these systems. As they age, microplastics in wastewater may both leach and sorb pollutants and fragment to provide an increased surface area for bacterial attachment and conjugation, possibly impacting antimicrobial resistance (AMR) traits. Despite this, little is known about the effects of persistent plastic pollution on microbial functioning. To address this knowledge gap, we deployed five different artificially weathered plastic types and a glass control into the final maturation pond of a municipal wastewater treatment plant in Otautahi-Christchurch, Aotearoa/New Zealand. We sampled the plastic-associated biofilms (plastisphere) at 2, 6, 26, and 52 weeks, along with the ambient pond water, at three different depths (20, 40, and 60 cm from the pond water surface). We investigated the changes in plastisphere microbial diversity and functional potential through metagenomic sequencing. Bacterial 16S ribosomal RNA genes composition did not vary among plastic types and glass controls (P = 0.997) but varied among sampling times [permutational multivariate analysis of variance (PERMANOVA), P = 0.001] and depths (PERMANOVA, P = 0.011). Overall, there was no polymer-substrate specificity evident in the total composition of genes (PERMANOVA, P = 0.67), but sampling time (PERMANOVA, P = 0.002) and depth were significant factors (PERMANOVA, P = 0.001). The plastisphere housed diverse AMR gene families, potentially influenced by biofilm-meditated conjugation. The plastisphere also harbored an increased abundance of genes associated with the biodegradation of nylon, or nylon-associated substances, including nylon oligomer-degrading enzymes and hydrolases.IMPORTANCEPlastic pollution is pervasive and ubiquitous. Occurrences of plastics causing entanglement or ingestion, the leaching of toxic additives and persistent organic pollutants from environmental plastics, and their consequences for marine macrofauna are widely reported. However, little is known about the effects of persistent plastic pollution on microbial functioning. Shotgun metagenomics sequencing provides us with the necessary tools to examine broad-scale community functioning to further investigate how plastics influence microbial communities. This study provides insight into the functional consequence of continued exposure to waste plastic by comparing the prokaryotic functional potential of biofilms on five types of plastic [linear low-density polyethylene (LLDPE), nylon-6, polyethylene terephthalate, polylactic acid, and oxygen-degradable LLDPE], glass, and ambient pond water over 12 months and at different depths (20, 40, and 60 cm) within a tertiary maturation pond of a municipal wastewater treatment plant.

Bioflocculation of pollutants in wastewater using flocculant derived from Providencia huaxiensis OR794369.1.

BACKGROUND: Water pollution has become a major environmental and health concern due to increasing population and industrialisation. Microbial flocculants are promising agents for treatment of contaminated water owing to their effectiveness, eco-friendliness, and high biosafety levels. In this study, culture conditions of Providencia huaxiensis OR794369.1 were optimised and its bioflocculant was extracted, characterised and used to treat wastewater. RESULTS: The maximum flocculating activity of 92% and yield of 3.5 g/L were obtained when cultivation conditions were: 3% inoculum size, starch, casein, initial pH of 6, cultivation temperature of 30 oC and 72 h of fermentation. The bioflocculant is an amorphous glycoprotein biomolecule with 37.5% carbohydrates, 27.9% protein, and 34.6% uronic acids. It is composed of hydroxyl, amino, alkanes, carboxylic acid and amines groups as its main functional structures. It was found to be safe to use as it demonstrated non-cytotoxic effects on bovine dermis and African green monkey kidney cells, illustrating median inhibitory concentration (IC50) values of 180 and > 500 µg/mL on both cell lines, respectively. It demonstrated the removal efficiencies of 90% on chemical oxygen demand (COD), 97% on biological oxygen demand (BOD) and 72% on Sulphur on coal mine wastewater. It also revealed the reduction efficacies of 98% (COD) and 92% (BOD) and 70% on Sulphur on domestic wastewater. CONCLUSION: The bioflocculant was effective in reducing pollutants and thus, illustrated potential to be used in wastewater treatment process as an alternative.

Design of a two functional permeable reactive barrier for synergistic enzymatic and microbial bioremediation of phenol-contaminated waters: laboratory column evaluation : Enzymatic and microbial bioremediation of phenol in a bilayer permeable reactive barrier.

The present study aimed to develop a system using a combination of enzymatic and microbial degradation techniques for removing phenol from contaminated water. In our prior research, the HRP enzyme extracted from horseradish roots was utilized within a core-shell microcapsule to reduce phenolic shock, serving as a monolayer column. To complete the phenol removal process, a second column containing degrading microorganisms was added to the last column in this research. Phenol-degrading bacteria were isolated from different microbial sources on a phenolic base medium. Additionally, encapsulated calcium peroxide nanoparticles were used to provide dissolved oxygen for the microbial population. Results showed that the both isolated strains, WC1 and CC1, were able to completely remove phenol from the contaminated influent water the range within 5 to 7 days, respectively. Molecular identification showed 99.8% similarity for WC1 isolate to Stenotrophomonas rizophila strain e-p10 and 99.9% similarity for CC1 isolate to Bacillus cereus strain IAM 12,605. The results also indicated that columns using activated sludge as a microbial source had the highest removal rate, with the microbial biofilm completely removing 100% of the 100 mg/L phenol concentration in contaminated influent water after 40 days. Finally, the concurrent use of core-shell microcapsules containing enzymes and capsules containing Stenotrophomonas sp. WC1 strain in two continuous column reactors was able to completely remove phenol from polluted water with a concentration of 500 mg/L for a period of 20 days. The results suggest that a combination of enzymatic and microbial degrading systems can be used as a new system to remove phenol from polluted streams with higher concentrations of phenol by eliminating the shock of phenol on the microbial population.

Crystal to Hydrogel Transformation in S-Benzyl-L-Cysteine-Containing Cyclic Dipeptides - Nanostructure Elucidation and Applications.

Cyclic dipeptides (CDPs) are crucial building blocks for a range of functional nanomaterials due to their simple chemical structure and high molecular stability. In this investigation, we synthesized a set of S-benzyl-L-cysteine-based CDPs (designated as P1-P6) and thoroughly examined their self-assembly behavior in a methanol-water solvent to elucidate the relationship between their structure and gelation properties. The hydrophobicity of the amino acids within the CDPs was gradually increased. The present study employed a comprehensive array of analytical techniques, including NMR, FT-IR, AFM, thioflavin-T, congo-red CD, X-ray crystallography, and biophysical calculations like Hirshfield Surface analysis and DFT analysis. These methods revealed that in addition to hydrogen bonding, the hydrophobic nature of the amino acid side chain significantly influences the propensity of CDPs to form hydrogels. Each CDP yielded distinct nanofibrillar networks rich in ß-sheet structures, showcasing unique morphological features. Moreover, we explored the practical application of these CDP-based hydrogels in water purification by utilizing them to remove harmful organic dyes from contaminated water. This application underscores the potential of CDPs in addressing environmental challenges, offering a promising avenue for the future development of these materials in water treatment technologies.

Adsorption of Organic Pollutants on Carbonaceous Adsorbents Prepared by Direct Activation of Sweet Cherry Stones.

The main objective of this study was to assess the usefulness of the sweet cherry stones for the production of carbonaceous adsorbents by means of direct physical activation method, using conventional and microwave variant of heating. The adsorbents were characterized in terms of textural parameters, acidic-basic character of the surface, electrokinetic properties and their suitability for drinking water purification. Adsorption tests were carried out against three organic compounds - Triton X-100 (surfactant), bovine serum albumin (protein) and methylene blue (synthetic dye). Depending on the variant of heating applied during activation procedure, the obtained activated biochars differed significantly in terms of the elemental composition, acidic-basic properties as well as degree of specific surface development and the type of porous structure generated. Adsorption tests have showed that the efficiency of organic pollutants removal from aqueous solutions depends significantly not only on the type of the adsorbent and adsorbate applied, but also on the temperature and pH of the system. The sample prepared by microwave-assisted direct activation proved to be very effective in terms of all tested organic pollutants adsorption. The maximum sorption capacity toward Triton X-100, bovine serum albumin and methylene blue reached the level of 86.5, 23.4 and 81.1 mg/g, respectively.

New insights into Chlorella vulgaris applications.

Environmental pollution is a big challenge that has been faced by humans in contemporary life. In this context, fossil fuel, cement production, and plastic waste pose a direct threat to the environment and biodiversity. One of the prominent solutions is the use of renewable sources, and different organisms to valorize wastes into green energy and bioplastics such as polylactic acid. Chlorella vulgaris, a microalgae, is a promising candidate to resolve these issues due to its ease of cultivation, fast growth, carbon dioxide uptake, and oxygen production during its growth on wastewater along with biofuels, and other productions. Thus, in this article, we focused on the potential of Chlorella vulgaris to be used in wastewater treatment, biohydrogen, biocement, biopolymer, food additives, and preservation, biodiesel which is seen to be the most promising for industrial scale, and related biorefineries with the most recent applications with a brief review of Chlorella and polylactic acid market size to realize the technical/nontechnical reasons behind the cost and obstacles that hinder the industrial production for the mentioned applications. We believe that our findings are important for those who are interested in scientific/financial research about microalgae.

Microalgae-mediated bioremediation: current trends and opportunities-a review.

Environmental pollution poses a critical global challenge, and traditional wastewater treatment methods often prove inadequate in addressing the complexity and scale of this issue. On the other hand, microalgae exhibit diverse metabolic capabilities that enable them to remediate a wide range of pollutants, including heavy metals, organic contaminants, and excess nutrients. By leveraging the unique metabolic pathways of microalgae, innovative strategies can be developed to effectively remediate polluted environments. Therefore, this review paper highlights the potential of microalgae-mediated bioremediation as a sustainable and cost-effective alternative to conventional methods. It also highlights the advantages of utilizing microalgae and algae-bacteria co-cultures for large-scale bioremediation applications, demonstrating impressive biomass production rates and enhanced pollutant removal efficiency. The promising potential of microalgae-mediated bioremediation is emphasized, presenting a viable and innovative alternative to traditional treatment methods in addressing the global challenge of environmental pollution. This review identifies the opportunities and challenges for microalgae-based technology and proposed suggestions for future studies to tackle challenges. The findings of this review advance our understanding of the potential of microalgae-based technology wastewater treatment.

Application of chlorine dioxide and its disinfection mechanism.

Chlorine dioxide (ClO2) is a strong oxidizing agent and an efficient disinfectant. Due to its broad-spectrum bactericidal properties, good inactivation effect on the vast majority of bacteria and pathogenic microorganisms, low resistance to drugs, and low generation of halogenated by-products, chlorine dioxide is widely used in fields such as water purification, food safety, medical and public health, and living environment. This review introduced the properties and application status of chlorine dioxide, compared the action mode, advantages and disadvantages of various disinfectants. The mechanism of chlorine dioxide inactivating bacteria, fungi and viruses were reviewed. The lethal target of chlorine dioxide to bacteria and fungi is to destroy the structure of cell membrane, change the permeability of cell membrane, and make intracellular substances flow out, leading to their death. The lethal targets for viruses are the destruction of viral protein capsids and the degradation of RNA fragments. The purpose of this review is to provide more scientific guidance for the application of chlorine dioxide disinfectants.

Treatment of agricultural wastewater using microalgae: A review.

The rapid development of agriculture has led to a large amount of wastewater, which poses a great threat to environmental safety. Microalgae, with diverse species, nutritional modes and cellular status, can adapt well in agricultural wastewater and absorb nutrients and remove pollutants effectively. Besides, after treatment of agricultural wastewater, the accumulated biomass of microalgae has broad applications, such as fertilizer and animal feed. This paper reviewed the current progresses and further perspectives of microalgae-based agricultural wastewater treatment. The characteristics of agricultural wastewater have been firstly introduced; Then the microalgal strains, cultivation modes, cellular status, contaminant metabolism, cultivation systems and biomass applications of microalgae for wastewater treatment have been summarized; At last, the bottlenecks in the development of the microalgae treatment methods, as well as recommendations for optimizing the adaptability of microalgae to wastewater in terms of wastewater pretreatment, microalgae breeding, and microalgae-bacterial symbiosis systems were discussed. This review would provide references for the future developments of microalgae-based agricultural wastewater treatment.

Comamonas resistens sp. nov. and Pseudomonas triclosanedens sp. nov., two members of the phylum Pseudomonadota isolated from the wastewater treatment system of a pharmaceutical factory.

Five strains of two novel species were isolated from the wastewater treatment systems of a pharmaceutical factory located in Zhejiang province, PR China. Strains ZM22T and Y6 were identified as belonging to a potential novel species of the genus Comamonas, whereas strains ZM23T, ZM24 and ZM25 were identified as belonging to a novel species of the genus Pseudomonas. These strains were characterized by polyphasic approaches including 16S rRNA gene analysis, multi-locus sequence analysis, average nucleotide identity (ANI), in silico DNA-DNA hybridization (isDDH), physiological and biochemical tests, as well as chemotaxonomic analysis. Genome-based phylogenetic analysis further confirmed that strains ZM22T and Y6 form a distinct clade closely related to Comamonas testosteroni ATCC 11996T and Comamonas thiooxydans DSM 17888T. Strains ZM23T, ZM24 and ZM25 were grouped as a separate clade closely related to Pseudomonas nitroreducens DSM 14399T and Pseudomonas nicosulfuronedens LAM1902T. The orthoANI and isDDH results indicated that strains ZM22T and Y6 belong to the same species. In addition, genomic DNA fingerprinting demonstrated that these strains do not originate from a single clone. The same results were observed for strains ZM23T, ZM24 and ZM25. Strains ZM22T and Y6 were resistant to multiple antibiotics, whereas strains ZM23T, ZM24 and ZM25 were able to degrade an emerging pollutant, triclosan. The phylogenetic, physiological and biochemical characteristics, as well as chemotaxonomy, allowed these strains to be distinguished from their genus, and we therefore propose the names Comamonas resistens sp. nov. (type strain ZM22=MCCC 1K08496T=KCTC 82561T) and Pseudomonas triclosanedens sp. nov. (type strain ZM23T=MCCC 1K08497T=JCM 36056T), respectively.