Molecularly imprinted polymers for environmental adsorption applications.

Molecular imprinting polymers (MIPs) are synthetic materials with pores or cavities to specifically retain a molecule of interest or analyte. Their synthesis consists of the generation of three-dimensional polymers with specific shapes, arrangements, orientations, and bonds to selectively retain a particular molecule called target. After target removal from the binding sites, it leaves empty cavities to be re-occupied by the analyte or a highly related compound. MIPs have been used in areas that require high selectivity (e.g., chromatographic methods, sensors, and contaminant removal). However, the most widely used application is their use as a highly selective extraction material because of its low cost, easy preparation, reversible adsorption and desorption, and thermal, mechanical, and chemical stability. Emerging pollutants are traces of substances recently found in wastewater, river waters, and drinking water samples that represent a special concern for human and ecological health. The low concentration in which these pollutants is found in the environment, and the complexity of their chemical structures makes the current wastewater treatment not efficient for complete degradation. Moreover, these substances are not yet regulated or controlled for their discharge into the environment. According to the literature, MIPs, as a highly selective adsorbent material, are a promising approach for the quantification and monitoring of emerging pollutants in complex matrices. Therefore, the main objective of this work was to give an overview of the actual state-of-art of applications of MIPs in the recovery and concentration of emerging pollutants.

Towards application of CRISPR-Cas12a in the design of modern viral DNA detection tools (Review).

Early detection of viral pathogens by DNA-sensors in clinical samples, contaminated foods, soil or water can dramatically improve clinical outcomes and reduce the socioeconomic impact of diseases such as COVID-19. Clustered regularly interspaced short palindromic repeat (CRISPR) and its associated protein Cas12a (previously known as CRISPR-Cpf1) technology is an innovative new-generation genomic engineering tool, also known as 'genetic scissors', that has demonstrated the accuracy and has recently been effectively applied as appropriate (E-CRISPR) DNA-sensor to detect the nucleic acid of interest. The CRISPR-Cas12a from Prevotella and Francisella 1 are guided by a short CRISPR RNA (gRNA). The unique simultaneous cis- and trans- DNA cleavage after target sequence recognition at the PAM site, sticky-end (5-7 bp) employment, and ssDNA/dsDNA hybrid cleavage strategies to manipulate the attractive nature of CRISPR-Cas12a are reviewed. DNA-sensors based on the CRISPR-Cas12a technology for rapid, robust, sensitive, inexpensive, and selective detection of virus DNA without additional sample purification, amplification, fluorescent-agent- and/or quencher-labeling are relevant and becoming increasingly important in industrial and medical applications. In addition, CRISPR-Cas12a system shows great potential in the field of E-CRISPR-based bioassay research technologies. Therefore, we are highlighting insights in this research direction.

Application of polysaccharide-based metal organic framework membranes in separation science.

Polysaccharide/MOF composite membranes have captured the interests of many researchers during decontamination of polluted environments. Their popularity can be attributed to the relatively high chemical and thermal stabilities of these composite membranes. Chitosan is among the polysaccharides extensively used during the synthesis of hybrid membranes with MOFs. The applications of chitosan/MOF composite membranes in separation science are explored in detail in this paper. Researchers have also synthesised mixed matrix membranes of MOFs with cellulose and cyclodextrin that have proved to be effective during separation of a variety of materials. The uses of cellulose/MOF and cyclodextrin/MOF membranes for the removal of environmental pollutants are discussed in this review. In addition, the challenges associated with the use of these mixed matrix membranes are explored in this current paper.

Antimicrobial Activity of Some Sudanese Medicinal Plants Against its Pollutant Isolated Bacteria.

<b>Background and Objective:</b> Medicinal plants have been known to cure many diseases due to the presence of active bio constituents, the goal of this study to detect and evaluate the effectiveness of antimicrobial activity of some Sudanese medicinal plants. <b>Materials and Methods:</b> Methanolic extracts of the following types of local medicinal plants <i>Artemisia herba-alba</i>,<i> Cyperus rotundus</i>,<i> Cymbopogon schoenanthus </i>sb<i> </i>sp.<i> Proximus</i>,<i> Trigonella foenum-graecum</i>,<i> Nigella sativa</i>,<i> Hyphaene thebaica</i>,<i> Nauclea latifolia</i> and <i>Ziziphus spina-christi</i> were tested against eight types of bacteria that were isolated from the same plants as their pollutants. Cup-plate method was used and then the inhibition zone of each plant was measured and compared with the inhibitory zone of some antibiotics used for the same isolates. <b>Results:</b> Methanol extracts of some plant species showed antibacterial activity against most of the studied bacterial species. <i>Cymbopogon schoenanthus </i>ssp.<i> Proximus </i>showed antibacterial activity against most isolated bacterial species in comparison with commercial antibiotics used. <b>Conclusion:</b> According to the findings of this research, severalmedicinal plants have efficacy and effect on certain types of bacteria and are superior or comparable to certain types of antibiotics. When compared to the other medicinal plants used in this study<i>, Cymbopogon schoenanthus </i>sbsp. <i>proximus </i>has the highest activity on most types of Gram-positive and Gram-negative bacteria, as well as the superiority of some antibiotics.

Antibiotics: An overview on the environmental occurrence, toxicity, degradation, and removal methods.

Antibiotics, as antimicrobial drugs, have been widely applied as human and veterinary medicines. Recently, many antibiotics have been detected in the environments due to their mass production, widespread use, but a lack of adequate treatment processes. The environmental occurrence of antibiotics has received worldwide attention due to their potential harm to the ecosystem and human health. Research status of antibiotics in the environment field is presented by bibliometrics. Herein, we provided a comprehensive overview on the following important issues: (1) occurrence of antibiotics in different environmental compartments, such as wastewater, surface water, and soil; (2) toxicity of antibiotics toward non-target organisms, including aquatic and terrestrial organisms; (3) current treatment technologies for the degradation and removal of antibiotics, including adsorption, hydrolysis, photodegradation and oxidation, and biodegradation. It was found that macrolides, fluoroquinolones, tetracyclines, and sulfonamides were most frequently detected in the environment. Compared to surface and groundwaters, wastewater contained a high concentration of antibiotic residues. Both antibiotics and their metabolites exhibited toxicity to non-target organisms, especially aquatic organisms (e.g., algae and fish). Fluoroquinolones, tetracyclines, and sulfonamides can be removed through abiotic process, such as adsorption, photodegradation, and oxidation. Fluoroquinolones and sulfonamides can directly undergo biodegradation. Further studies on the chronic effects of antibiotics at environmentally relevant concentrations on the ecosystem were urgently needed to fully understand the hazards of antibiotics and help the government to establish the permissible limits. Biodegradation is a promising technology; it has numerous advantages such as cost-effectiveness and environmental friendliness.

Carrageenan-based nano-hybrid materials for the mitigation of hazardous environmental pollutants.

Fast industrialization and population growth are associated with the increased release of hazardous contaminants in the environment. These hazardous substances, including pharmaceutical, biomedical, personal-care products, heavy metals, endocrine-disrupters, and colorants, pollute the ecosystem by disturbing nature's balance. Nanotechnology has paved new horizons in biochemical engineering by designing novel approaches of integrating nanoscale science with biotechnology to construct improved quality materials for target uptake of pollutants. Recently, nanostructured materials have emerged as research and development frontiers owing to their excellent properties. The tailored designing of nanohybrids constructs with physicochemical alteration enables the nano-bioadsorbent with high target specificity and efficiency. The development of eco-friendly, biodegradable, cost-efficient, and biopolymer-based nanohybrid constructs is gaining attention to remove hazardous environmental pollutants. κ-carrageenan biopolymer is frequently used with different nanomaterials to design nanohybrid bio-adsorbents to remove various contaminants. Herein, the potentialities of carrageenan-based nanohybrid constructs in environmental remediation have been summarized. Different nanostructures, e.g., silica, non-magnetic/magnetic, carbon nanotubes/nanorods, nanoclay/nanomembrane, metal organic frameworks, graphene oxide, and other nanomaterials have been described in combination with carrageenan biopolymers focusing on environmental remediation.

Pollutant Degrading Enzyme: Catalytic Mechanisms and Their Expanded Applications.

The treatment of environmental pollution by microorganisms and their enzymes is an innovative and socially acceptable alternative to traditional remediation approaches. Microbial biodegradation is often characterized with high efficiency as this process is catalyzed via degrading enzymes. Various naturally isolated microorganisms were demonstrated to have considerable ability to mitigate many environmental pollutants without external intervention. However, only a small fraction of these strains are studied in detail to reveal the mechanisms at the enzyme level, which strictly limited the enhancement of the degradation efficiency. Accordingly, this review will comprehensively summarize the function of various degrading enzymes with an emphasis on catalytic mechanisms. We also inspect the expanded applications of these pollutant-degrading enzymes in industrial processes. An in-depth understanding of the catalytic mechanism of enzymes will be beneficial for exploring and exploiting more degrading enzyme resources and thus ameliorate concerns associated with the ineffective biodegradation of recalcitrant and xenobiotic contaminants with the help of gene-editing technology and synthetic biology.

Prediction and Understanding: Quantum Chemical Framework of Transition Metals Enclosed in a B12N12 Inorganic Nanocluster for Adsorption and Removal of DDT from the Environment.

Emission of harmful pollutants from different sources into the environment is a major problem nowadays. Organochlorine pesticides such as DDT (C14H9Cl5) are toxic, bio-accumulative, and regularly seen in water bodies, air, biota, and sediments. Various systems can be considered for minimizing the DDT (dichloro-diphenyl-trichloroethane) pollution. However, due to simplicity and acceptability, the adsorption method is the most popular method. Adsorption is gradually employed for the removal of both organic and inorganic pollutants found in soil and water. Thus, in this regard, efforts are being made to design inorganic nanoclusters (B12N12) encapsulated with late transition metals (Zn, Cu, Ni, Co, and Fe) for effective adsorption of DDT. In this context, detailed thermodynamics and quantum chemical study of all the designed systems have been carried out with the aid of density functional theory. The adsorption energy of DDT on metals cocooned in a nanocluster is found to be higher, and better adsorption energy values as compared to that of the pristine B12N12-DDT nanocluster have been reported. Further, analysis of the dipole moment, frontier molecular orbitals, molecular electrostatic potential plots, energy band gap, QNBO, and Fermi level suggested that the late-transition-metal-encapsulated inorganic B12N12 nanoclusters are efficient candidates for effective DDT adsorption. Lastly, the study of global descriptors of reactivity confirmed that the designed quantum mechanical systems are quite stable in nature with a good electrophilic index. Therefore, the recommendation has been made for these novel kinds of systems to deal with the development of DDT sensors.

Current Applications of Magnetic Nanomaterials for Extraction of Mycotoxins, Pesticides, and Pharmaceuticals in Food Commodities.

Environmental pollutants, such as mycotoxins, pesticides, and pharmaceuticals, are a group of contaminates that occur naturally, while others are produced from anthropogenic sources. With increased research on the adverse ecological and human health effects of these pollutants, there is an increasing need to regularly monitor their levels in food and the environment in order to ensure food safety and public health. The application of magnetic nanomaterials in the analyses of these pollutants could be promising and offers numerous advantages relative to conventional techniques. Due to their ability for the selective adsorption, and ease of separation as a result of magnetic susceptibility, surface modification, stability, cost-effectiveness, availability, and biodegradability, these unique magnetic nanomaterials exhibit great achievement in the improvement of the extraction of different analytes in food. On the other hand, conventional methods involve longer extraction procedures and utilize large quantities of environmentally unfriendly organic solvents. This review centers its attention on current applications of magnetic nanomaterials and their modifications in the extraction of pollutants in food commodities.

Sustainable Materials and their Contribution to the Sustainable Development Goals (SDGs): A Critical Review Based on an Italian Example.

The Sustainable Development Goals (SDGs) have been proposed to give a possible future to humankind. Due to the multidimensional characteristic of sustainability, SDGs need research activities with a multidisciplinary approach. This work aims to provide a critical review of the results concerning sustainable materials obtained by Italian researchers affiliated to the National Interuniversity Consortium of Materials Science and Technology (INSTM) and their contribution to reaching specific indicators of the 17 SDGs. Data were exposed by using the Web of Science (WoS) database. In the investigated period (from 2016 to 2020), 333 works about sustainable materials are found and grouped in one of the following categories: chemicals (33%), composites (11%), novel materials for pollutants sequestration (8%), bio-based and food-based materials (10%), materials for green building (8%), and materials for energy (29%). This review contributes to increasing the awareness of several of the issues concerning sustainable materials but also to encouraging the researchers to focus on SDGs' interconnections. Indeed, the mapping of the achievements can be relevant to the decision-makers to identify the opportunities that materials can offer to achieve the final goals. In this frame, a "Sustainable Materials Partnership for SDGs" is envisaged for more suitable resource management in the future.

Overexpression of Capsular Polysaccharide Biosynthesis Protein in Lactobacillus plantarum P1 to Enhance Capsular Polysaccharide Production for Di-n-butyl Phthalate Adsorption.

Exopolysaccharides (EPSs) such as capsular polysaccharide (CPS) are important bioactive carbohydrate compounds and are often used as bioenrichment agents and bioabsorbers to remove environmental pollutants like di-n-butyl phthalate (DBP). Among the EPS-producing bacteria, lactic acid bacteria (LAB) have gained the most attention. As generally recognized as safe (GRAS) microorganisms, LAB can produce EPSs having many different structures and no health risks. However, EPS production by LAB does not meet the needs of large-scale application on an industrial scale. Here, the capA gene (encoding CPS biosynthesis protein) was overexpressed in Lactobacillus plantarum P1 to improve the production of EPSs and further enhance the DBP adsorption capability. Compared with P1, the CPS production in capA overexpressed strain was increased by 11.3 mg/l, and the EPS thickness was increased from 0.0786 ± 0.0224 µm in P1 to 0.1160 ± 0.0480 µm in P1-capA. These increases caused the DBP adsorption ratio of P1-capA to be doubled. Overall, the findings in this study provide a safe method for the adsorption and removal of DBP.

Microbial Sensing and Removal of Heavy Metals: Bioelectrochemical Detection and Removal of Chromium(VI) and Cadmium(II).

The presence of inorganic pollutants such as Cadmium(II) and Chromium(VI) could destroy our environment and ecosystem. To overcome this problem, much attention was directed to microbial technology, whereas some microorganisms could resist the toxic effects and decrease pollutants concentration while the microbial viability is sustained. Therefore, we built up a complementary strategy to study the biofilm formation of isolated strains under the stress of heavy metals. As target resistive organisms, Rhizobium-MAP7 and Rhodotorula ALT72 were identified. However, Pontoea agglumerans strains were exploited as the susceptible organism to the heavy metal exposure. Among the methods of sensing and analysis, bioelectrochemical measurements showed the most effective tools to study the susceptibility and resistivity to the heavy metals. The tested Rhizobium strain showed higher ability of removal of heavy metals and more resistive to metals ions since its cell viability was not strongly inhibited by the toxic metal ions over various concentrations. On the other hand, electrochemically active biofilm exhibited higher bioelectrochemical signals in presence of heavy metals ions. So by using the two strains, especially Rhizobium-MAP7, the detection and removal of heavy metals Cr(VI) and Cd(II) is highly supported and recommended.

Silica Monolith for the Removal of Pollutants from Gas and Aqueous Phases.

This study focused on the application of mesoporous silica monoliths for the removal of organic pollutants. The physico-chemical textural and surface properties of the monoliths were investigated. The homogeneity of the textural properties along the entire length of the monoliths was assessed, as well as the reproducibility of the synthesis method. The adsorption properties of the monoliths for gaseous toluene, as a model of Volatile Organic Compounds (VOCs), were evaluated and compared to those of a reference meso-structured silica powder (MCM-41) of commercial origin. Silica monoliths adsorbed comparable amounts of toluene with respect to MCM-41, with better performances at low pressure. Finally, considering their potential application in water phase, the adsorption properties of monoliths toward Rhodamine B, selected as a model molecule of water soluble pollutants, were studied together with their stability in water. After 24 h of contact, the silica monoliths were able to adsorb up to the 70% of 1.5 × 10-2 mM Rhodamine B in water solution.

Recent Advances in the Synthesis, Properties, and Applications of Modified Chitosan Derivatives: Challenges and Opportunities.

Chitosan is a very well-known biocompatible and biodegradable polysaccharide consisting of ß-(1-4)-linked glucosamine units, derived from the deacetylation of chitin. This unique biopolymer consists of primary amines as well as hydrophilic hydroxyl groups along with the chitosan backbone and has exceptional properties and wide applications. Numerous articles have been devoted to the preparation and properties of chitosan-based biomaterials, which have been demonstrated as beads, films, fibers (2D-scaffolds), gels, sponges (3D-scaffolds), and wound-healing materials. The unusual adsorption capacity of chitosan cross-linked polymer is demonstrated by trapping cations, anions, organic dyes, and pharmaceutical ingredients from wastewater. The most striking manifestations of flexibility in the preparation of these adsorbents have been critically reviewed, and their sorption efficiencies compared. Notably, these materials are also used as drug delivery carriers. Further, various metal-loaded chitosan-based nanocomposite materials have been used efficiently in organic catalytic reactions. As per the rich literature survey, such chitosan-based materials warrant further research due to their abundance, eco-friendliness, and effectiveness towards commercialization. The biotechnological aspects of chitosan may lead to promising low-cost materials and by-products of industrial and agricultural significance. The constant demand for potential adsorbents for the removal of pollutants, can be met by fine-tuning the structural properties of chitosan with appropriate cross-linkers or additives.

Pesticides and their metabolites in human urine: development of multi-analyte method by LC-MS/MS and GC-MS/MS.

The objective of this study consists of being able to develop a precise, reliable, easy, cheap and quick method to identify and quantify the presence of pesticide metabolites and their parents in human urine. In order to reach our purpose we selected the pesticides and their metabolites with intended uses on permanent crops such as orchards and vineyard. The activity planning started with the identification of the target list carried out by UHPLC-MS/MS and GC-MS/MS, succeeded by several tests oriented to determine the best sample treatment having recourse to instrumental analysis in the range 5-100 ng/mL. Several purifications were also investigated combining different adsorbents (PSA, EMR-lipid and final polish pouch). The use of formic acid during the extraction step has no impact on the recoveries, whereas the PSA adsorbent in the cleanup step negatively affects the results for all investigated metabolites. Any substantial differences were not observed in urine matrix for parent compounds achieving recoveries higher than 80% and RSD less than 20%. The final polish in combination or not with Enhanced Matrix Removal EMR-lipid did not show statistically significant difference in term of trueness and precision for both metabolites and parents, as evaluated by one-way ANOVA. The 3-OH THPI was the most critical compound with not acceptable results for linearity, trueness and precision.

Recent Achievements in Dyes Removal Focused on Advanced Oxidation Processes Integrated with Biological Methods.

In the last 3 years alone, over 10,000 publications have appeared on the topic of dye removal, including over 300 reviews. Thus, the topic is very relevant, although there are few articles on the practical applications on an industrial scale of the results obtained in research laboratories. Therefore, in this review, we focus on advanced oxidation methods integrated with biological methods, widely recognized as highly efficient treatments for recalcitrant wastewater, that have the best chance of industrial application. It is extremely important to know all the phenomena and mechanisms that occur during the process of removing dyestuffs and the products of their degradation from wastewater to prevent their penetration into drinking water sources. Therefore, particular attention is paid to understanding the mechanisms of both chemical and biological degradation of dyes, and the kinetics of these processes, which are important from a design point of view, as well as the performance and implementation of these operations on a larger scale.

Study on detoxification and removal mechanisms of hexavalent chromium by microorganisms.

Extensive industrial activities have led to an increase of the content of chromium in the environment, which causes serious pollution to the surrounding water, soil and atmosphere. The enrichment of chromium in the environment through the food chain ultimately affects human health. Therefore, the remediation of chromium pollution is crucial to development of human society. A lot of scholars have paid attention to bioremediation technology owing to its environmentally friendly and low-cost. Previous reviews mostly involved pure culture of microorganisms and rarely discussed the optimization of bioreduction conditions. To make up for these shortcomings, we not only introduced in detail the conditions that affect microbial reduction but also innovatively introduced consortium which may be the cornerstone for future treatment of complex field environments. The aim of this study is to summary chromium toxicity, factors affecting microbial remediation, and methods for enhancing bioremediation. However, the actual application of bioremediation technology is still facing a major challenge. This study also put forward the current research problems and proposed future research directions, providing theoretical guidance and scientific basis for the application of bioremediation technology.

Removing Pb2+ with a pectin-rich fiber from sisal waste.

A pectin-rich dietary fiber from sisal waste (P-SF), containing 11.8% pectin, was produced by a sequential enzymatic-ultrasonic process. P-SF was effective in adsorbing Pb2+ from aqueous solution with a maximum adsorption amount of 184 mg g-1. Adsorption isotherms were fitted well by the Langmuir equation, and the adsorption kinetics could be described by a pseudo-second-order model. X-ray photoelectron spectroscopy and energy dispersive spectroscopy suggested that Pb2+ was adsorbed by P-SF via ion exchange, complexation and mineral precipitation. Dietary supplementation with 10% (w/w) P-SF in basal feed led to a significant decrease in Pb2+ in the brain, liver and kidney. P-SF has greater in vivo efficacy of Pb2+ removal as compared to commercial soybean dietary fiber. The reduction of brain Pb2+ level by P-SF was as effective as by a Pb2+ excretion drug. These findings suggested that P-SF has a great potential to be used as a dietary supplement to cope with Pb2+ poisoning.

A novel process for the covalent immobilization of laccases on silica gel and its application for the elimination of pharmaceutical micropollutants.

In the present work, pharmaceutical micropollutant degradation by laccase immobilized on silica through an innovative process is proposed. The influence of different parameters on the immobilization conditions was evaluated by a 23 full factorial design, and parameters leading to the highest activity were identified. Under these conditions, laccase activity reached 14 ± 2 U g-1 of silica with a protein immobilization yield of 35%. The biocatalyst characterization did not show any change in pH and thermal stabilities but enhanced the long-term storage of laccases. Immobilized T. versicolor laccases were then tested to remove four pharmaceutical micropollutants (amoxicillin, ciprofloxacin, carbamazepine, and sulfamethoxazole) in the presence of redox mediators (syringaldehyde, p-coumaric acid, and ABTS). High removal yields (50-100% according to the pollutant) were obtained within 4 h of treatment due to the synergistic effect of laccase-mediator biotransformation and adsorption on the support. Overall, the pharmaceuticals' removal efficiency was highly influenced by their physicochemical properties; however, the presence of redox mediators impacted not only the oxidation mechanism but also the interactions between the biocatalyst and micropollutants. Finally, the reusability of the biocatalyst was proved during 7 degradation cycles.