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Three methods of cellulose-derived polyol synthesis were elaborated. The suitable substrates were (hydroxypropyl)cellulose or cellulose, which were hydroxyalkylated in reactions with glycidol and ethylene carbonate in triethylene glycol or in water. The products were characterized by IR, 1H NMR, and MALDI ToF spectroscopies. For all polyols, IR spectra showed strong bands at 1060 cm−1 from the ether group formed upon the ring opening of GL and EC. The polyol obtained from (hydroxypropyl)cellulose in the triethylene glycol solvent was accompanied by oligomeric products of glycol hydroxyalkylation and oligomeric glycidol. The polyol obtained by the hydroxyalkylation of cellulose with glycidol and ethylene carbonate in the water contained units of hydroxyalkylated cellulose and products of hydroxyalkylation of water. The physical properties of the obtained polyols, like density, viscosity, and surface tension, were determined. The polyols were then used to obtain rigid polyurethane foams. The foams have apparent density, water uptake, and polymerization shrinkage similar to classic rigid PUFs. The foams showed advantageous thermal resistance in comparison with classic ones. After thermal exposure, their compressive strength improved. The biodegradation of the obtained materials was tested by a respirometric method in standard soil conditions by the measurement of biological oxygen demand and also using the cellulases or the enzymes responsible for cellulose degradation. It has been found that polyols are totally biodegradable within one month of exposure, while the foams obtained thereof are at least 50% biodegraded in the same conditions. The enzymatic biodegradation of the PUFs by the action of microbial cellulase was confirmed. [ABSTRACT FROM AUTHOR]

When exposed to different building environmental conditions, bio-composite materials, such as hemp mortars, represent a risk of mold proliferation. This later plays a critical role in the biodeterioration of the materials when their physical properties are locally modified by the natural aging process. The primary objectives of the present work are first to assess the evolution of the surface of contaminated mortar; second, to investigate an accurate DNA extraction method that could be used for both bio-composite mortars and their fiber sources collected in situ; then, to understand the process of the proliferation of mold strains on both hemp shives and hemp mortar; and finally, to compare mold strains present in these phases to show their relationship to mold contamination and their impact on human health. In situ hemp mortar contamination behavior was investigated in the region of Pau (France) two months after hemp mortar application in extreme conditions (high humidity, low temperature, no aeration), which did not match the standard conditions under which hemp mortar must be used. The SEM observations and FTIR and pH analyses highlighted the decrease in pH level and the presence of organic matter on the mortar surface. DNA sequencing results showed that hemp shives were the main source of fungal contamination of hemp mortar. A mold population analysis showed that the most dominant phylum was Ophistokonta, which represented 83.6% in hemp shives and 99.97% in hemp mortar. The Acrostalagmus genus representatives were the most abundant, with 42% in hemp shives and 96% in hemp mortar. The interconnection between the mold strain characteristics (particularly the ability to grow in extreme environments) and the presence of hemp mortar was emphasized. [ABSTRACT FROM AUTHOR]

Excessive use of plastic mulches has triggered a series of environmental problems, primarily due to the large volumes generated and their low or non-existent degradability. For this reason, materials with similar characteristics to synthetic mulches but with a biodegradable character were sought. In this work, mulch films were produced from gelatin/glycerol/cellulose (GelC) and chitosan/glycerol/cellulose (ChiC). Their biodegradation time in soil and photographic analysis using scanning electron microscopy (SEM) were determined. The GelC sample presented a weight loss of 80% at 25 days, compared to 58% for the ChiC sample in the same exposure time. However, the latter was the only sample that could be evaluated up to 70 days, during which it presented its greatest weight loss (97%). The SEM results for both mulch films showed some color changes after 30 days; complete fracturing, growth of mycelium on the surface, and the presence of pores were observed. FTIR spectra revealed a decrease in hydroxyl groups, amides, and carbonyl bands as the number of degradation days increased. Obtaining polymers from waste materials, such as mango, represents an important task to obtain cellulose that can both reinforce and provide biodegradable properties to biobased materials, which can be degraded by microorganisms present in the soil. [ABSTRACT FROM AUTHOR]

Natural minerals play a key role in the burgeoning field of mineral-reinforced polymers, providing an important element in strengthening and toughening the properties of composite materials. This article presents a comprehensive overview of the use of minerals in mineral-reinforced polymers, covering various aspects of their applications and impact on the final properties of these materials. The potential of various types of natural minerals (for example talc, montmorillonite, halloysite, diatomite) as reinforcements in mineral-reinforced polymers is discussed. Techniques for producing mineral-reinforced polymers using minerals, including the mixing method, impregnation, and coating application, are presented in detail. In addition, the effects of process parameters and component ratios on the final properties of mineral-reinforced polymers are discussed. The latest research on the use of minerals in mineral-reinforced polymers is also presented, including their effects on the strength, stiffness, resistance to environmental conditions, and biodegradation of the materials. Finally, the development prospects and potential applications of mineral-reinforced polymers with minerals in various industrial sectors, including packaging, automotive, construction, and medicine, are discussed. [ABSTRACT FROM AUTHOR]

Ceramic materials have a very long tradition of use in construction. Their durability is related to the surface of the material and the action of the corrosive environment. One of the corrosive factors acting on ceramic materials is microorganisms. They can contribute to the deterioration of the technical and performance properties of building materials. Aesthetic, physical, and chemical deterioration are considered to be the main destructive processes in ceramic materials. This work shows how the different types of the most commonly used ceramic materials, i.e., brick and tiles, are damaged. Each of these types is susceptible to microbial growth. Most microorganisms that occur on ceramic materials produce staining substances and thus form coloured biofilms. The direct action of metabolic products secreted by organisms on inorganic substrates is the main cause of chemical biodeterioration. Therefore, this work presents the impact of microorganisms on ceramic building materials. [ABSTRACT FROM AUTHOR]

The total petroleum hydrocarbons (TPH) in used engine oil-polluted soil constrains its natural bioattenuation. Synergistic actions of biostimulation and bioaugmentation in microbial biodegradation mediated by the addition of keratinaceous materials resulted in the biodegradation of TPH. In this study, keratinous materials served as the source of organic nutrients to improve the soil's physicochemical properties and promote the proliferation of keratinolytic and hydrocarbonoclastic bacteria. After the biodegradation activity, the TPH declined from 48,865 mg kg−1 to a threshold lower than 10,000 mg kg−1 in 180 days except in the control groups. The TPH biodegradation efficiencies ranged between 70.5–91.5% in the treatment groups S1, S2 and S3 while natural bioattenuation in control groups S4 and S5 ranged between 18.5–22.5%. Biodegradation kinetics modelling indicated decay rates (0.0075 to 0.0137 per day) and half-life (50.38 to 91.29 days) in the treatment groups, while the control group recorded decay rates (0.0011 to 0.0014 per day) and half-life (487.29 to 616.74) days. From the culture-independent analysis to identify the keratinolytic and hydrocarbonoclastic bacteria in the soil, the changes in bacterial community structures bacterial dynamics, diversity, community structure and phylogenesis were determined. The keratinolytic and hydrocarbonoclastic bacteria identified were made up of Proteobacteria (52%), Actinobacteriota (22%), Firmicutes (4%), Planctomycetota (2%), Acidobacteriota (2%) and Chloroflexi (1%). The AlkB gene copies in the treatment groups increased from 6.25 × 105 to 1.25 × 107 copies ng DNA−1, while the control groups decreased from 6.20 × 105 copies ng DNA−1 to 6.05 × 104 copies ng DNA−1 in 180 days. [ABSTRACT FROM AUTHOR]

The unresolved challenges in the development of highly efficient, stable and controlled synthetic microbial consortia, as well as the use of natural consortia, are very attractive for science and technology. However, the consortia management should be done with the knowledge of how not only to accelerate but also stop the action of such "little pots". Moreover, there are a lot of microbial consortia, the activity of which should be suppressively controlled. The processes, catalyzed by various microorganisms being in complex consortia which should be slowed down or completely cancelled, are typical for the environment (biocorrosion, landfill gas accumulation, biodegradation of building materials, water sources deterioration etc.), industry (food and biotechnological production), medical practice (vaginitis, cystitis, intestinal dysbiosis, etc.). The search for ways to suppress the functioning of heterogeneous consortia in each of these areas is relevant. The purpose of this review is to summarize the general trends in these studies regarding the targets and new means of influence used. The analysis of the features of the applied approaches to solving the main problem confirms the possibility of obtaining a combined effect, as well as selective influence on individual components of the consortia. Of particular interest is the role of viruses in suppressing the functioning of microbial consortia of different compositions. [ABSTRACT FROM AUTHOR]

Lignocellulosic materials, made up of cellulose, hemicellulose, and lignin, constitute some of the most prevalent types of biopolymers in marine ecosystems. The degree to which marine microorganisms participate in the breakdown of lignin and their impact on the cycling of carbon in the oceans is not well understood. Strain LCG002, a novel Marivivens species isolated from Lu Chao Harbor's intertidal seawater, is distinguished by its ability to metabolize lignin and various aromatic compounds, including benzoate, 3-hydroxybenzoate, 4-hydroxybenzoate and phenylacetate. It also demonstrates a broad range of carbon source utilization, including carbohydrates, amino acids and carboxylates. Furthermore, it can oxidize inorganic gases, such as hydrogen and carbon monoxide, providing alternative energy sources in diverse marine environments. Its diversity of nitrogen metabolism is supported by nitrate/nitrite, urea, ammonium, putrescine transporters, as well as assimilatory nitrate reductase. For sulfur assimilation, it employs various pathways to utilize organic and inorganic substrates, including the SOX system and DSMP utilization. Overall, LCG002's metabolic versatility and genetic profile contribute to its ecological significance in marine environments, particularly in the degradation of lignocellulosic material and aromatic monomers. [ABSTRACT FROM AUTHOR]

The vast majority of cultural heritage objects consist of materials that can be subjected to biodeterioration. Currently, there is significant number of publications showing which materials are capable of destroying certain organisms, and what conservation and restoration procedures are required. However, there is neither a clear classification of these diverse events nor their visual representation. In our review, for the first time, an attempt is made to compare the type of biodeterioration, based on the destruction of a particular material, with a specific color of the rainbow. In this regard, a cultural heritage objects made of a single material are designated as one color icon; and those made of composite materials are designated as pictogram consisting of several icons of corresponding colors. For example, a stone sculpture, in accordance with the rainbow code, is assigned a gray color, which was introduced to visualize stone materials. The drum corresponds to a pictogram consisting of violet (corresponds to leather) and brown (corresponds to wood). A work of easel painting on canvas corresponds to a pictogram consisting of a red color icon (corresponds to canvas) and a gold color icon (corresponds to painting materials). We used cold color shades to denote basic inorganic materials, and cold color shades to denote organic materials. The proposed rainbow code for biodetermination is an open platform that can be expanded by adding new colors for new materials introduced, and allows to translate potentially any cultural heritage object into a pictogram with colors that correspond to the materials used in its manufacture. Such a graphical interpretation can help both systematize the storage conditions of museum exhibits and facilitate understanding of the processes of biodeterioration of composite materials. [ABSTRACT FROM AUTHOR]

The stability and composting behaviour of monolayers and laminates of poly (lactic acid) (PLA) and starch with and without active extracts and cellulose fibres from rice straw (RS) were evaluated. The retrogradation of the starch throughout storage (1, 5, and 10 weeks) gave rise to stiffer and less extensible monolayers with lower water vapour barrier capacity. In contrast, the PLA monolayers, with or without extract, did not show marked changes with storage. However, these changes were more attenuated in the bilayers that gained water vapour and oxygen barrier capacity during storage, maintaining the values of the different properties close to the initial range. The bioactivity of the active films exhibited a slight decrease during storage, so the antioxidant capacity is better preserved in the bilayers. All monolayer and bilayer films were fully composted within 90 days but with different behaviour. The bilayer assembly enhanced the biodegradation of PLA, whose monolayer exhibited a lag period of about 35 days. The active extract reduced the biodegradation rate of both mono- and bilayers but did not limit the material biodegradation within the time established in the Standard. Therefore, PLA–starch laminates, with or without the valorised fractions from RS, can be considered as biodegradable and stable materials for food packaging applications. [ABSTRACT FROM AUTHOR]

Highlights: A comprehensive introduction into organic cathode materials for aqueous zinc-ion batteries with specific focus on their structural–property relationship based on the variations in composition, geometry, and molecular size. For each representative organic cathode, the unique electrochemistry has been discussed to provide insight into the underlying working mechanism. Summarized pros and cons of different organic cathodes and outlined challenges plus future research directions. Aqueous zinc-ion batteries (AZIBs) are one of the most compelling alternatives of lithium-ion batteries due to their inherent safety and economics viability. In response to the growing demand for green and sustainable energy storage solutions, organic electrodes with the scalability from inexpensive starting materials and potential for biodegradation after use have become a prominent choice for AZIBs. Despite gratifying progresses of organic molecules with electrochemical performance in AZIBs, the research is still in infancy and hampered by certain issues due to the underlying complex electrochemistry. Strategies for designing organic electrode materials for AZIBs with high specific capacity and long cycling life are discussed in detail in this review. Specifically, we put emphasis on the unique electrochemistry of different redox-active structures to provide in-depth understanding of their working mechanisms. In addition, we highlight the importance of molecular size/dimension regarding their profound impact on electrochemical performances. Finally, challenges and perspectives are discussed from the developing point of view for future AZIBs. We hope to provide a valuable evaluation on organic electrode materials for AZIBs in our context and give inspiration for the rational design of high-performance AZIBs. [ABSTRACT FROM AUTHOR]

Food packaging is an important concept for consumer satisfaction and the increased shelf life of food products. The introduction of novel food packaging materials has become an emerging trend in recent years, which could be mainly due to environmental pollution caused by plastic packaging and to reduce food waste. Recently, numerous studies have been carried out on nanoclays or nanolayered silicate to be used in packaging material development as reinforcing filler composites. Different types of nanoclays have been used as food packaging materials, while montmorillonite (MMT), halloysite, bentonite (BT), Cloisite, and organically modified nanoclays have become of great interest. The incorporation of nanoclays into the packaging matrix improves the mechanical and barrier properties and at the same time prolongs the biodegradation of the packaging material. The purpose of this article is to examine the development of nanoclay-based food packaging materials. The review article highlights the current state of research on bio-based polymers with nanoclay for food packaging. In addition, the report analyses the mechanical, barrier, and antibacterial characteristics of nanoclay-based food packaging materials. Finally, it discusses the migration of nanoclays, toxicity levels, and the legislation associated with the application of nanoclays. [ABSTRACT FROM AUTHOR]

Hybrid porous polymers based on poly-EGDMA and polylactide containing vancomycin, the concentration of which in the polymer varied by two orders of magnitude, were synthesized. The processes of polymer biodegradation and vancomycin release were studied in the following model media: phosphate-buffered saline (PBS), trypsin-Versene solution, and trypsin-PBS solution. The maximum antibiotic release was recorded during the first 3 h of extraction. The duration of antibiotic escape from the polymer samples in trypsin-containing media varied from 3 to 22 days, depending on the antibiotic content of the polymer. Keeping samples of the hybrid polymer in trypsin-containing model media resulted in acidification of the solutions—after 45 days, up to a pH of 1.84 in the trypsin-Versene solution and up to pH 1.65 in the trypsin-PBS solution. Here, the time dependences of the vancomycin release from the polymer into the medium and the decrease in pH of the medium correlated. These data are also consistent with the results of a study of the dynamics of sample weight loss during extraction in the examined model media. However, while the polymer porosity increased from ~53 to ~60% the pore size changed insignificantly, over only 10 μm. The polymer samples were characterized by their antibacterial activity against Staphylococcus aureus, and this activity persisted for up to 21 days during biodegradation of the material, regardless of the medium type used in model. Surface-dependent human cells (dermal fibroblasts) adhere well, spread out, and maintain high viability on samples of the functionalized hybrid polymer, thus demonstrating its biocompatibility in vitro. [ABSTRACT FROM AUTHOR]

Plastics have increasingly dominated our material landscape due to their widespread use. With the surge in the production and distribution of plastic products, the threat of global plastic pollution has escalated. This issue has increasingly alarmed environmental researchers due to the pronounced negative impacts on flora and fauna. As research efforts intensify worldwide, there is encouraging advancement in pinpointing and comprehending microorganisms capable of breaking down these plastics. The recent studies depicted microbial entities for their remarkable capabilities in tackling plastic waste. Among these are bacteria from the genera Ideonella, Pseudomonas, Enterobacter and Brevibacillus, as well as fungi, especially those from the genera Aspergillus and Penicillium which have showcased promising results in degrading plastics This scholarly review aims to clarify the lasting understanding concerning the biodegradation of polymeric materials. We delve into the different roles of specific microorganisms adept at plastic degradation, highlighting the enzymatic capabilities they employ. Additionally, we explore the environmental implications of leveraging microbial degradation as a sustainable approach to mitigating plastic pollution, offering insights into future research directions and applications. [ABSTRACT FROM AUTHOR]

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Cellulose diacetate (CDA) is a bio-based plastic widely used in consumer products. CDA is a promising alternative to conventional thermoplastics due to its susceptibility to biodegradation in various environments. Despite widespread evidence for the degradation of CDA, relatively little is known about the microorganisms that drive degradation, particularly in the ocean. Recently, we documented the biodegradation of CDA-based materials (i.e., fabric, film, and foam) in a continuous-flow natural seawater mesocosm on the timescales of months, as indicated by mass loss, enzyme activity, and respiration to carbon dioxide. These findings paved the way for the present study aimed at identifying key microbial taxa implicated in CDA degradation. Analysis based on 16S rRNA gene amplicon sequencing of bacteria and archaea revealed that material type, incubation time, material morphology (e.g., fabric vs film), and plasticizer content significantly influenced the microbial community structure. Differential abundance analysis revealed that bacterial taxa affiliated with the families of Arenicellaceae, Cellvibrionaceae, Methyloligellaceae, Micavibrionaceae, Puniceicoccaceae, Spirosomaceae, and Thermoanaerobaculaceae, and the order of Pseudomonadales potentially initiated the degradation (i.e., deacetylation) of CDA fabric and film. These taxa were notably distinct from CDA-degrading microbes reported in non-seawater environments. Collectively, the findings lend further support for CDA as a promising next-generation, high-utility, and low-environmental persistence bioplastic material. IMPORTANCE Cellulose diacetate (CDA) is a promising alternative to conventional plastics due to its versatility in manufacturing and low environmental persistence. Previously, our group demonstrated that CDA is susceptible to biodegradation in the ocean on timescales of months. In this study, we report the composition of microorganisms driving CDA degradation in the coastal ocean. We found that the coastal ocean harbors distinct bacterial taxa implicated in CDA degradation and these taxa have not been previously identified in prior CDA degradation studies, indicating an unexplored diversity of CDA-degrading bacteria in the ocean. Moreover, the shape of the plastic article (e.g., a fabric, film, or foam) and plasticizer in the plastic matrix selected for different microbial communities. Our findings pave the way for future studies to identify the specific species and enzymes that drive CDA degradation in the marine environment, ultimately yielding a more predictive understanding of CDA biodegradation across space and time. [ABSTRACT FROM AUTHOR]

• The bioactive protective PEO-coating is formed on bioresorbable Mg-0.8Ca alloy. • A uniform distribution of hydroxyapatite over the thickness of coating is proved. • PEO-layer makes it possible to control the process of material's biodegradation. • The mechanism of biodegradation of the coated material in vitro is established. • The prospects for application of formed coating in implant surgery are highlighted. In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation (PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, SEM-EDX analysis, and micro-Raman spectroscopy. The uniform distribution of hydroxyapatite over the thickness of protective PEO-layer was established. Using traditional (EIS, PDP, OCP) and local scanning electrochemical methods (SVET, SIET with H+-selective microelectrode), the level of protective properties of PEO-layer in a biological environment (mammalian cell culture medium, MEM) was determined. It was established that modification of Mg-0.8Ca alloy surface by PEO contributes to a significant increase in the corrosion resistance of the surface layer, making it possible to control the process of material's biodegradation. The maximum local electrochemical activity was recorded after 72 h of testing, while for the uncoated sample, intense corrosion degradation was recorded in the first 12 min of exposure to the cell culture medium. Formation of the PEO-coating results in a twofold decrease in the corrosion current density (2.8ˑ10−6 A cm−2) and an increase in the impedance modulus measured at a low frequency (1.7ˑ104 Ω cm2) in comparison with the uncoated material (9.5ˑ10−6 A cm−2; 8.1ˑ103 Ω cm2). The mechanism of material bioresorption was established and a model for biodegradation process of Mg-0.8Ca alloy with hydroxyapatite-containing PEO-coating in MEM was proposed. Analysis of these results and comparing with others obtained by various scientific groups indicate the prospects for application of biocompatible PEO-coating on Mg-Ca alloy in implant surgery. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal materials are widely used in the degradation of pollutants, especially for the degradation of some refractory organics in sewage. A large and growing body of researchers has investigated the relationship between the fate of antibiotics and antibiotic resistance genes (ARGs) and the addition of iron-based materials during anaerobic digestion (AD) of sludge. In this article, firstly, the mechanisms by which iron-based materials affect the biodegradation of antibiotics in the process of AD are discussed. The biodegradation of antibiotics is promoted through physical and chemical reactions such as adsorption, redox, and chelation, and the improvement of microbial activity after iron-based materials is added. Secondly, the effect of iron-based materials on ARGs in AD is discussed in this article. The addition of iron-based materials can reduce the generation and spread of ARGs by altering the microbial community, affecting the proliferation of mobile genetic elements (MGEs), the synergistic effect of metal resistance genes (MRGs) and ARGs, and other pathways. Finally, the application and development prospects of iron-based materials in the biodegradation of antibiotics during AD are prospected. [ABSTRACT FROM AUTHOR]

Caffeine is a verified bio-protective substance in the fight against the biodegradation of cellulose materials, but its ecotoxicity in this context has not yet been studied. For this reason, the ecotoxicity of flax-fiber-reinforced epoxy composite with or without caffeine was tested in the present study. Prepared samples of the composite material were tested on freshwater green algal species (Hematococcus pluvialis), yeasts (Saccharomyces cerevisae), and crustacean species (Daphnia magna). Aqueous eluates were prepared from the studied material (with caffeine addition (12%) and without caffeine and pure flax fibers), which were subjected to chemical analysis for the residues of caffeine or metals. The results indicate the presence of caffeine up to 0.001 mg/L. The eluate of the studied material was fully toxic for daphnids and partially for algae and yeasts, but the presence of caffeine did not increase its toxicity statistically significantly, in all cases. The final negative biological effects were probably caused by the mix of heavy metal residues and organic substances based on epoxy resins released directly from the tested composite material. [ABSTRACT FROM AUTHOR]

Despite its reputation as the most widely used restorative dental material currently, resin-based materials have acknowledged shortcomings. As most systematic survival studies of resin composites and dental adhesives indicate, secondary caries is the foremost reason for resin-based restoration failure and life span reduction. In subjects with high caries risk, the microbial community dominated by acidogenic and acid-tolerant bacteria triggers acid-induced deterioration of the bonding interface and/or bulk material and mineral loss around the restorations. In addition, resin-based materials undergo biodegradation in the oral cavity. As a result, the past decades have seen exponential growth in developing restorative dental materials for antimicrobial applications addressing secondary caries prevention and progression. Currently, the main challenge of bioactive resin development is the identification of efficient and safe anticaries agents that are detrimental free to final material properties and show satisfactory long-term performance and favorable clinical translation. This review centers on the continuous efforts to formulate novel bioactive resins employing 1 or multiple agents to enhance the antibiofilm efficacy or achieve multiple functionalities, such as remineralization and antimicrobial activity antidegradation. We present a comprehensive synthesis of the constraints and challenges encountered in the formulation process, the clinical performance-related prerequisites, the materials' intended applicability, and the current advancements in clinical implementation. Moreover, we identify crucial vulnerabilities that arise during the development of dental materials, including particle aggregation, alterations in color, susceptibility to hydrolysis, and loss of physicomechanical core properties of the targeted materials. [ABSTRACT FROM AUTHOR]

The structure and physicochemical properties of glycoluril were studied to evaluate the possibility of using it as a filler additive to polymer composite materials to stimulate their biodegradation. The mean particle size of glycoluril was determined (5–10 μm). Glycoluril was found to be stable at temperatures below 270°C. Its particles efficiently reflect visible light. Glycoluril particles and their aggregates have high specific surface area. High parameters of glycoluril bioassimilation with a mold fungus culture determine the potential of this compound for use in biodegradable polymer compound formulations. [ABSTRACT FROM AUTHOR]

Plastic can be a good solution for the industry and, even if plastic products might be designed and produced for circular usage, conventional methods production of it and waste management are not reliable solutions anymore. Plastic pollution became a very serious problem for the environment around the world today. Several studies shown us that microplastic is a very dangerous form of pollution and increasing amounts of it can be found in animals and human's bodies. However, recent studies provide us important data about the involvement of microorganisms in biodegradation of polymer materials. Biodegradation process is based on the ability of some microorganisms to degrade certain plastic pollutants through their metabolic activity. Many microorganisms have the ability to secrete specific degradation enzymes that participates in degrading processes of plastic. In this review we discuss about various microorganisms and their role in plastic degradation. We review different types of approaches and applications of molecular biology used for identifying microorganisms capable of degrading polymers and key genes involved in polymers degradation. [ABSTRACT FROM AUTHOR]

Nanopharmaceuticals represent a group of nanoparticles engineered for medical purposes. Nowadays, nanotechnology offers several possibilities to improve the safety and efficacy of medicines by designing advanced carrier systems which have been found to offer particular advantages when formulated in the nanoscale. Some of the initially marketed nano-formulations already demonstrate advantages over conventional formulations. Innovative delivery systems offer the possibility to not only control drug release but also to overcome biological barriers. For the translation of new drug products from bench to bedside, however, it is pivotal to test and prove their safety. This is of course also true for nanopharmaceuticals, where in particular the biocompatibility and also the clearance/biodegradation of the carrier material after drug delivery has to be demonstrated. The pulmonary route offers some great opportunities for noninvasive drug delivery but also implicates peculiar challenges. Advanced aerosol formulations with innovative drug carriers have already contributed to the significant progress of inhalation therapy. However, in spite of the large alveolar epithelial surface area, the respiratory tract still features diverse efficient biological barriers, primarily designed by nature to protect the human body against inhaled pollutants and pathogens. Only a thorough understanding of particle-lung interactions will allow the rational design of novel nanopharmaceuticals capable of overcoming these barriers, while of course always keeping in mind the strict demands for their safety. While the recent resurrection of inhaled insulin has already confirmed the potential of the pulmonary route for systemic delivery of biopharmaceuticals, inhaled nanopharmaceuticals, currently under investigation, promise to improve also local therapies like anti-infectives. [ABSTRACT FROM AUTHOR]

• Reconstruction experiments of biodeterioration on materials are crucial in testing biocides. • Interference of biocides with materials and pigments cannot be neglected. • Stone porosity strongly affects the biocidal efficiency. • Eco-friendly emulsifiers can act as tertiary bioreceptivity agents. Hypogeal environments due to their limited air circulation, low constant temperatures and high humidity could be threatened by microbial spreading. In cultural heritage preservation, natural bioactive molecules have been proposed as a possible alternative to traditional biocides. Although several papers report the in vitro effect of green biocides, scant information is available about their efficacy in direct application and interaction with historical materials. Then, we investigated five green biocidal formulations never applied before to control the biodeterioration of subterranean mural painting raising from Italian and South Korean traditions. We tested three emulsified essential oil-based (oregano and clove bud) water suspensions, and usnic acid-based water and 2-propanol/dimethyl sulfoxide (7:3) solutions for establishing: (i) possible interference with the reconstructed ancient wall paintings materials (colour and water adsorption changes), (ii) efficacy on recurrent biodeteriogens, trough optical/electronic microscopy, bioluminometric and culture-based methods. Results evidenced the different impact of such biocides on wall paintings' materials and pigments (e.g., higher on red and black Etruscan tiles). They also highlight the importance of reconstruction experiments for customizing treatments, avoiding interference with historical materials (e.g., changes in colour) and biodeteriogens' spreading. The active principles concentration and stone porosity strongly affect the biocidal efficacy, but the solvent and emulsifier used also had a relevant role. [Display omitted] [ABSTRACT FROM AUTHOR]

Surfactants with an ester bond connecting the polar headgroup and the hydrophobic tail are common. They are easy to synthesize, they can often be made from natural raw materials and their biodegradation profile is generally good, partly due to lipase or esterase catalyzed breakdown of the ester bond in sewage plants. A labile ester bond in the molecule may cause problems, however. Surfactants are often formulated at relatively high pH and it is important that they remain intact for a given period of time. In this article we discuss alkaline hydrolysis of different types of ester‐based surfactants—cationic, anionic and nonionic—and also of surfactant mixtures. We show that the ester bond in a surfactant has a different hydrolysis pattern than ester bonds in non‐surface active uncharged molecules. Cationic ester‐based surfactants are hydrolyzed rapidly while anionic and also nonionic ester‐containing surfactants are relatively resistant to hydrolysis. [ABSTRACT FROM AUTHOR]

This paper deals with investigating the feasibility of using waste plum pits in the production of composite particleboard materials and the improvement of their mechanical and physical properties. Biodegradability, flammability and water absorption are the primary disadvantages of wood-based composites, which reduce their service life. In this experimental study, waste colemanite was used to decrease the known flammability of wood composites. Phenol formaldehyde (PF) was used to increase the water resistance and prevent biodegradability of the prepared materials, and hemp fiber was added to increase their mechanical strength. Thus, the objective was to avoid the disadvantages of wood-based materials. Based on the results of the flexural strength test, the optimum polymer composite material production parameters were determined to be as follows: 0.50 filler/binder ratio, 56 kg/cm2 moulding pressure and 0.75 hemp fiber ratio. According to the results of the experiments, the use of waste colemanite in the production of composite materials improves their non-flammability, while decreasing flexural and screw withdrawal strengths. It was determined that waste plum pits could be used to substitute for wood chips, as an alternative filler material in the production of composite materials. As a result, eco-friendly polymer composite materials were produced from waste plum pits, hemp fiber, and waste colemanite. The obtained composite materials are compliant with applicable standards and are suitable for application as building materials for use in both interior and exterior space. [ABSTRACT FROM AUTHOR]

Microbial growth on surfaces poses health concerns and can accelerate the biodegradation of engineered materials and coatings. Cyclic peptides are promising agents to combat biofouling because they are more resistant to enzymatic degradation than their linear counterparts. They can also be designed to interact with extracellular targets and intracellular targets and/or self-assemble into transmembrane pores. Here, we determine the antimicrobial efficacy of two pore-forming cyclic peptides, α-K3W3 and β-K3W3, against bacterial and fungal liquid cultures and their capacity to inhibit biofilm formation on coated surfaces. These peptides display identical sequences, but the additional methylene group in the peptide backbone of β-amino acids results in a larger diameter and an enhancement in the dipole moment. In liquid cultures, β-K3W3 exhibited lower minimum inhibitory concentration values and greater microbicidal power in reducing the number of colony forming units (CFUs) when exposed to a gram-positive bacterium, Staphylococcus aureus, and two fungal strains, Naganishia albida and Papiliotrema laurentii. To evaluate the efficacy against the formation of fungal biofilms on painted surfaces, cyclic peptides were incorporated into polyester-based thermoplastic polyurethane. The formation of N. albida and P. laurentii microcolonies (105 per inoculation) for cells extracted from coatings containing either peptide could not be detected after a 7-day exposure. Moreover, very few CFUs (∼5) formed after 35 days of repeated depositions of freshly cultured P. laurentii every 7 days. In contrast, the number of CFUs for cells extracted from the coating without cyclic peptides was >8 log CFU. [ABSTRACT FROM AUTHOR]

• Achieving high waterproofing in modified cellulose sheets using silylated starch. • Accelerating to biodegradation rate of starch-modified cellulose material by water. • Increasing service life and decay acceleration by fungi for modified paper. Modifying natural polymers with silicones gives new possibilities for packaging products and waste management. In this study, the innovative papers produced were altered following the reaction of polysaccharides and organosilicon compounds. The susceptibility of the studied material to biodegradation caused by a brown-rot fungus was assessed. Strength properties by tensile strength and dynamic mechanical analysis and hydrophobic properties by water uptake test and water contact angle analysis were evaluated. Moreover, elemental analysis by ICP method was controlled. The durability against fungi and the hydrophobic properties were increased by the modification. The fungal decay resistance of the silanized paper was reduced by water storage, which allows for managing paper waste. Cellulose-based paper treated with starch-modified methyltrimethoxysilane showed potential as a packaging material due to its reduced water uptake. Possible application areas could be corrugated boxes, cellulose thermoformed products for electronics, and food packaging. However, the water-repellent effect is limited to short-term exposure in humid conditions. [ABSTRACT FROM AUTHOR]

Compounds of plant origin are used in biodegradable polymers as stabilizers and functional additives. However, these substances often have a biological activity (antimicrobial) that can affect the biodegradability of these polymers. The objective of this work is to study the effect of two polyphenols, quercetin and gallic acid on the biodegradability of the natural polyester poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The biodegradation of the materials was evaluated in pure liquid culture media in the presence of the PHBV-degrading bacterium Streptomyces exfoliatus, and also by a respirometric test in compost. The bacterial inhibition was demonstrated from the second and fourth month of incubation in the presence of quercetin and gallic acid, respectively. This was confirmed by optical microscopic observations of the bacterial cells (showing the disappearance of the bacterial filament network) and scanning electron microscopy analysis (showing no structural change on the surface of the additivated films). However, all the films produced were considered fully biodegradable, according to the specification standard NF T51-800, leading to the conclusion that the use of polyphenolic additives to PHBV materials (instead of synthetic additives) to improve their functionality is not an obstacle to their biodegradation in home compost. [ABSTRACT FROM AUTHOR]

Plastic materials are recalcitrant in the open environment, surviving for longer without complete remediation. The current disposal methods of used plastic material are inefficient; consequently, plastic wastes are infiltrating the natural resources of the biosphere. The mixed composition of urban domestic waste with different plastic types makes them unfavorable for recycling; however, natural assimilation in situ is still an option to explore. In this research work, we have utilized previously published reports on the biodegradation of various plastics types and analyzed the pattern of microbial degradation. Our results demonstrate that the biodegradation of plastic material follows the chemical classification of plastic types based on their main molecular backbone. The clustering analysis of various plastic types based on their biodegradation reports has grouped them into two broad categories of C-C (non-hydrolyzable) and C-X (hydrolyzable). The C-C and C-X groups show a statistically significant difference in their biodegradation pattern at the genus level. The Bacilli class of bacteria is found to be reported more often in the C-C category, which is challenging to degrade compared to C-X. Genus enrichment analysis suggests that Pseudomonas and Bacillus from bacteria and Aspergillus and Penicillium from fungi are potential genera for the bioremediation of mixed plastic waste. The lack of uniformity in reporting the results of microbial degradation of plastic also needs to be addressed to enable productive growth in the field. Overall, the result points towards the feasibility of a microbial-based biodegradation solution for mixed plastic waste. [ABSTRACT FROM AUTHOR]

Octacalcium phosphate (OCP) has been advocated as a precursor of bone apatite crystals. Recent studies have shown that synthetic OCP exhibits highly osteoconductive properties as a bone substitute material that stems from its ability to activate bone tissue-related cells, such as osteoblasts, osteocytes, and osteoclasts. Accumulated experimental evidence supports the proposition that the OCP-apatite phase conversion under physiological conditions increases the stimulatory capacity of OCP. The conversion of OCP progresses by hydrolysis toward Ca-deficient hydroxyapatite with Ca2+ ion incorporation and inorganic phosphate ion release with concomitant increases in the solid Ca/P molar ratio, specific surface area, and serum protein adsorption affinity. The ionic dissolution rate during the hydrolysis reaction was controlled by introducing a high-density edge dislocation within the OCP lattice by preparing it through co-precipitation with gelatin. The enhanced dissolution intensifies the material biodegradation rate and degree of osteogenecity of OCP. Controlling the biodegradation rate relative to the dissolution acceleration may be vital for controlling the osteogenecity of OCP materials. This study investigates the effects of the ionic dissolution of OCP, focusing on the structural defects in OCP, as the enhanced metastability of the OCP phase modulates biodegradability followed by new bone formation. Octacalcium phosphate (OCP) is recognized as a highly osteoconductive material that is biodegradable by osteoclastic resorption, followed by new bone formation by osteoblasts. However, if the degradation rate of OCP is increased by maintaining the original osteoconductivity or acquiring a bioactivity better than its current properties, then early replacement with new bone can be expected. Although cell introduction or growth factor addition by scaffold materials is the standard method for tissue engineering, material activity can be augmented by introducing dislocations into the lattice of the OCP. This review article summarizes the effects of introducing structural defects on activating OCP, which was obtained by co-precipitation with gelatin, as a bone substitute material and the mechanism of improved bone replacement performance. [Display omitted] [ABSTRACT FROM AUTHOR]

There are two main themes in the research on the biodegradation of industrial materials by mycelial fungi. The challenge of reducing environmental pollution necessitates the creation of biodegradable polymers that allow microorganisms, including mycelial fungi, to degrade them to low-molecule soluble substances. Additionally, to minimize the biodegradation of industrial materials while they are operating in the environment, there is a need to produce fungi-resistant polymer compositions. The fungal resistance of industrial materials and products can be assessed using a specific set of mycelial fungi cultures. Test cultures selected for this purpose are supported in the All-Russian Collection of Microorganisms (VKM). This review addresses the principle of culture selection to assess the fungal resistance of industrial materials and evaluates the results of the tests using these cultures. [ABSTRACT FROM AUTHOR]

Understand the process of biodegradation of lignocellulosic material as its chemical composition is key properties for enhancing the cultivation of edible mushrooms, which seek in lignin and other carbon source carbohydrates. The purpose of this study was to monitor polysaccharide and lignin degradation caused by Pleurotus ostreatoroseus on different agroindustrial substrates using near infrared spectroscopy (NIR). Sawdust substrates of Marupá and Cajuí wood, banana pseudostem fibers, enriched with bran of cereals were formulated (WB and MWB). Of the 12 formulations elaborated, eight were submitted to biodegradation of P. ostreatoroseus over a period of 49 days (Residual substrate), and four formulations maintained in natura (Initial substrates), where each treatment was formed by 10 replicates totaling n = 120. Spectra were obtained from the substrates before and after cultivation in FT-NIR system in the region between 10,000 and 4,000 cm-1 and the index degradation of lignocellulosic compounds was determined (LDI and PDI). Through Fourier transform near infrared spectroscopy was it is possible to observe the degradation of polysaccharides and lignin in the substrates grown with the fungus P. ostreatoroseus. In the residual substrate Marupá+WB-POSP was the highest lignin degradation index (LDI = 9.26%). While whereas for the PDI (Polysaccharide degradation index), the highest degradation (7.12%) was observed in the residual substrate Cajuí+MWB-POAM. Through analysis of the absorption bands, it was possible to observe the degradation of structures/bonds characteristics of lignocellulosic residues. The NIR model for degradation of lignocellulosic compounds was more effective in predicting "lignin degradation" in the spectral range 6,350-7,308 cm-1. [ABSTRACT FROM AUTHOR]

Chitosan is one of the prospective polymers for use in regenerative medicine which has unique properties such as biocompatibility, biodegradability, antimicrobial, anti-inflammatory, and antitumor potency. In this article, we study the peculiarities of the surface modification of chitosan films with carbonyl-containing compounds, which differed both in molecular characteristics and in their hydrophilic and hydrophobic properties. The potential for controlling the biodegradation of the resulting materials has been established, which can be used in the creation of wound dressings. Both the destruction time and lyophilic properties of the surface depend on the length of the modifier's hydrocarbon radical. The contact angle and water absorption of obtained film materials correlate with hydrophobicity, which estimated by the calculated value of the hydrophilic–lipophilic balance. The cytotoxicity of modified chitosan films was studied, and it was found that they are non-toxic (cytotoxic index of < 50%) for human skin cell cultures, which shows their potential for use in the creation of materials for skin protection and external wound healing. [ABSTRACT FROM AUTHOR]

Biopolymers used to mitigate the environmental impact needed establish biodegradation percentage. The thermal and structural changes of two plastic materials, a flexible film based on cassava starch - Poly(lactic acid) (PLA) and a semi-rigid cassava flour-stay cellulose fique fiber, were evaluated biodegradation under ISO 4855-1 standard. The tests were carried out for four weeks at constant temperature and flow of 58 °C ± 2 °C and 250 mL/h, using a mature compost as inoculum. The percentages of CO 2 , thermal, morphological, and structural changes, variation of degradation temperatures, glass transition temperatures (T g), Melting temperatures (T m) and enthalpies of fusion (H m), were properly evaluated as indicators of the materials biodegradation of two materials. Scanning electron microscopy (SEM), showed the microorganisms colonization on the materials surface, evidencing the appearance of cracks and microbial population. The flexible film showed a biodegradation percentage of 98.24 %, the semi-rigid tray 89.06 %, and the microcrystalline cellulose, 81.37 %. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing interest in soil additives used in environmental ecosystems. Currently, most soil amendments are produced from synthetic materials. Some synthetic amendments break down into microplastics, which persist in the environment and can be ingested by soil organisms, affecting soil health and biodiversity and the chemicals they contain can leach into groundwater. At the same time, the number and availability of biodegradable technologies are limited, and the aspects related to their biodegradation in soil are not sufficiently known. The study developed a sustainable water-saving and vegetation-supporting technology in the form of a biodegradable water-absorbing geocomposite (BioWAG). BioWAGs were produced using biodegradable materials derived from animal and plant waste, such as waste wool, jute, and linen. In a three-year field experiment, their physicochemical properties in the soil were analysed. These were characterized using a.o. Surface weight, scanning electron microscopy (SEM), and FTIR. The results indicate that the degree of biodegradation of materials used in BioWAG depended on the raw material and production technology. Needle-punched nonwovens underwent intensive biodegradation just 6 months after being buried in the soil, while stitched nonwovens retained their mechanical properties even for three growing seasons. In the case of seamed non-woven fabrics, a decrease in selected physical parameters was observed. The addition of wool-based soil additive, a decrease in surface mass was observed by 85% after 6 months, 88% after 18 months and 90% after 30 months. Regardless of the waste materials used, BioWAGs provided plants with continuous access to water and nutrients. The work indicates a sustainable method of managing textile waste and analyzes its properties in the soil, which enables the development of technologies based on natural fibers for applications such as geotextiles, mulches and controlled-release fertilizers. The technology was developed in line with the principles of a circular economy and can improve soil quality, mitigate the effects of climate change and reduce environmental pollution. [Display omitted] • Over 10 million plastics enter the environment annually. • Biodegradable materials can replace synthetics in up to half of applications. • Textile waste offers alternative for the production of biodegradable technologies. • Textile biodegradable waste was used to produce a new type of soil additive. • Understanding degradation processes is key to using sustainable technologies effectively. [ABSTRACT FROM AUTHOR]

Biofilms are created when micro-colonies adhere to a solid surface and produce a strong extracellular matrix which increases the risk of infection and impedes the healing process of bone defects. Although post-operative antibiotics are commonly prescribed to prevent infections, they carry the risk of side effects and antibiotic resistance. Current research explored the potential of magnesium doped zinc oxide incorporated silk fibroin scaffolds to prevent the biofilms formation for alveolar bone regeneration applications. Novel silk fibroin (SF)/hydroxyapatite (HA) scaffolds incorporated with magnesium-doped zinc oxide nanoparticles (Mg–ZnO NPs with 0.5, 1 and 2 % Mg) were fabricated by freeze gelation method. The data suggested that new materials exhibit remarkable antibacterial activity against Staphylococcus aureus. Moreover, these materials are also found to be both biodegradable and biocompatible. The study revealed that scaffolds displayed excellent antibacterial activity that was increased with increasing concentration of Mg in ZnO, with a maximum of 49.39 % was observed for 2 % of Mg doped ZnO. Additionally, biodegradation of the material also increases with the increase in concentration of Mg doping in ZnO. The adequate porosity in the range of 67 %–74.3 % was recorded of new materials substituted with Mg–ZnO, which led to improved cell viability (99.6 %) and uniform deposition of apatite over the surface of scaffolds, making it an excellent candidate for biomedical applications that require antibacterials properties with high cell viability. [Display omitted] • A novel nanocomposite scaffold of SF/HA/SA/Mg–ZnO was successfully synthesized by freeze gelation method. • The composite scaffold showed remarkable antibacterial activity against Staphylococcus aureus. • The composite scaffold showed good biodegradation and porosity and improved cell viability in vitro. [ABSTRACT FROM AUTHOR]

In this study, two essential oils (EOs) with preventive proved biocidal efficacy, namely oregano and eugenol, are encapsulated in silica nanocontainer, then dispersed in multifunctional, hybrid and nanocomposite coating. The aim of this work is to reduce toxicity of restoration materials, to avoid the chemicals dispersion in the environment and to extent stone protection treatments, preventing biofouling. Composite silica nanocapsules, containing separately the two EOs, are prepared via one-step synthesis, based on oil-in-water miniemulsion polymerisation processes, and fully characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N 2 physisorption (BET/BJH). Micro-Raman spectroscopy (RS) and thermal analysis (TG/DSC). In a second step, nanocomposite coatings, based on a flexible tetraethyl orthosilicate (TEOS) matrix, are synthesised dispersing TiO 2 nanoparticles and the two silica nanocapsules incorporating EOs. The coatings were applied on three different lithotypes samples of historical importance: brick, piperine and mortar. The effectiveness and compatibility of the coating formulation with the different stone substrates were assessed through a multi-analytical standard protocol. The silica nanocapsules, show monodispersed spherical shape with size ∼110 nm, a core-shell structure, a BET surface area of 600–700 m2/g and high loading capacity. The results on coatings characterisation show a crack-free and transparent structure. Moreover, the tests on applied coatings reveal the high hydrophobicity of the treated stone samples (static contact angle in the range ∼ 130–140° and reduction of liquid water capillary absorption 97–99 %) and unaltered permeability to water vapour (density of water vapour flow rate in the range 150–200 g/m2·d), demonstrating the suitability of the nanocomposite hybrid coatings for the application in stone protection against biodeterioration. [Display omitted] • Nanocomposite hybrid coatings have been synthesised to contrast biodeterioration of stones. • Essential oils are successfully encapsulated in mesoporous core-shell silica nanocapsules. • Nanocapsules and photocatalytic TiO 2 nanoparticles are dispersed in the hybrid polymetric matrix. • Crack-free and transparent coatings are obtained and tested on different stone substrates. • Treated stone surfaces show very high hydrophobicity and unaltered permeability to water vapour. [ABSTRACT FROM AUTHOR]

The durability of cementitious materials in harsh environments, like marine or sulfate-rich soils, is influenced by various factors, with bacteria playing a significant role alongside environmental chemistry. To address sustainability concerns, research focuses on developing cement mixes that reduce emissions and withstand aggressive conditions. New standards require testing these mixes. This study developed and tested low-carbon cement mixes (CEM III, CEM V, CAC, and CSS) under real sewer conditions enriched with H 2 S and bacteria for four years. The specimens underwent SEM-EDS, XRD, TGA-DTA, and µRaman analysis to enhance understanding of degradation processes by conducting detailed and localized characterization of both initial and newly formed phases. Through this analysis, the work offers a precise description of the effects of bio-alteration on various cement matrices, elucidating their reactions under such conditions. The analysis of mortar specimens has revealed the presence of expansive products such as gypsum besides various polymorphs of calcium carbonate. • Impact of severe H 2 S levels on low-carbon cementitious materials in sewer networks. • In-depth discussion on layer-by-layer alteration phenomena. • Greater resistance of CAC and CSS mortar specimens compared to PC-based specimens. • High-precision techniques are crucial for accurately assessing biodeterioration. [ABSTRACT FROM AUTHOR]

In this paper, screen-printed electrodes are asymmetrically fabricated on three different dielectrics (multi-layered polyimide, quartz, and alumina). Supplied with AC power, sustainable surface dielectric barrier discharge (SDBD) plasma is generated in atmospheric pressure. During plasma processing, different changes of material degradation and discharge images are observed. The corresponding electrical and optical characteristics are investigated by optical emission spectra (OES) and Lissajous figure analysis, respectively. It is found that both dielectric degradation and electrode erosion occur on the surface of the polyimide based SDBD device, while there is only electrode erosion for the quartz and alumina based devices, which results in different changes of electrical characteristics. OES calculated results show that with an increase of discharge aging time, electron temperature increases for the polyimide based SDBD device and decreases for quartz and alumina based SDBD devices, while all the gas temperatures of three dielectrics increase with the aging time. Furthermore, compared to vibrational temperature and gas temperature, the distribution of electron temperature is more suitable for evaluating the changes in discharge uniformity during plasma processing. [ABSTRACT FROM AUTHOR]

Pine processionary caterpillar nests are made from raw silk. Fibroin protein is the main component of silk which, in the case of pine processionary caterpillar, has some unusual properties such as a higher resistance to chemical hydrolysis. Isolation of microorganisms naturally present in silk nests led to identification of Bacillus licheniformis and Pseudomonas aeruginosa strains that in a defined minimal medium were able to carry out extensive silk biodegradation. A LasB elastase-like protein from P. aeruginosa was shown to be involved in silk biodegradation. A recombinant form of this protein expressed in Escherichia coli and purified by affinity chromatography was able to efficiently degrade silk in an in vitro assay. However, silk biodegradation by B. licheniformis strain was mediated by a SubC subtilisin-like protease. Homologous expression of a subtilisin Carlsberg encoding gene (subC) allowed faster degradation compared to the biodegradation kinetics of a wildtype B. licheniformis strain. This work led to the identification of new enzymes involved in biodegradation of silk materials, a finding which could lead to possible applications for controlling this pest and perhaps have importance from sanitary and biotechnological points of view. [ABSTRACT FROM AUTHOR]

Microorganisms are one of the main factors in the deterioration of cultural heritage, in particular art paintings. The antiseptics currently used in painting have significant limitations due to insufficient effectiveness or increased toxicity and interaction with art materials. In this regard, the actual challenge is the search for novel materials that effectively work against microorganisms in the composition with painting materials and do not change their properties. Chitosan has pronounced antimicrobial properties but was not used previously as an antiseptic for paintings. In our study we developed a number of mock layers based on sturgeon glue, supplemented which chitosan (molecular weight 25 kDa or 45 kDa), standard antiseptics for paintings (positive controls) or without additives (negative control). According to Fourier transform infrared spectroscopy and atomic force microscopy, the addition of chitosan did not significantly affect the optical and surface properties of this material. The ability of chitosan to effectively protect paintings was shown after inoculation on the created mock-up layers of 10 fungi-destructors of tempera painting, previously isolated from cultural heritage of the of the 15–16th centuries in the State Tretyakov Gallery, on the created mock layers. Our study demonstrated the principled opportunity of using chitosan in the composition of painting materials to prevent biodeterioration for the first time. [ABSTRACT FROM AUTHOR]

• Biodeterioration is one of the most frequent afflictions found in deteriorated art • The artwork itself functions as an ecological niche • Fungi and bacteria are prevalent biodeterioration agents of modern materials • Certain treatments may be the answer for the base material but damage the surface • Biological impact does not decrease despite contemporary material incorporation • A model of action was developed for poly-material contemporary art pieces Biodeterioration is one of the most common alteration factors affecting cultural heritage, and its appearance responds to numerous factors. Awareness of the risk it poses to heritage material and the study of its development is essential. With the mass production evolution of widely accessible materials, the criteria for choosing the constituents of a work of art no longer respond to traditional premises, associating the conservation of these new materials with the flawed expectation of longevity and stable resistance to biological attack. This work aims to update the contemporary preventive conservation practice through the review of the biodeterioration risk of indoor poly-material artworks. It also means analyzing the potential incidence of biological agents deteriorating contemporary materials stored in art collections, characterized by their industrial origin, and frequently used in the pieces produced in the current art scene. Due to their characteristic agglomeration of components, the artistic object is subjected to complicated surveillance and problematic biological control and eradication, which can often be contraindicated for some constituents. The study encompasses four main points that make up the risk review analysis sequence: a brief art history exposition to understand poly-material creative values; a general definition of terms surrounding biodeterioration; a selection of most used contemporary materials and a study of their biodeterioration risks; and the basic preventive conservation considerations regarding biological attacks. The review concludes with a critical analysis of the complicated issue of preventive treatment compatibility, as well as a proposed model of action and consideration towards heritage pieces endangered or affected by biological attacks. [Display omitted] [ABSTRACT FROM AUTHOR]

Polymers with low environmental impact are of great interest worldwide to reduce greenhouse gases (CO2 and CH4) and soil and water contamination. Evaluating the biodegradation process of biopolymeric matrices obtained from different biodegradable biopolymers is a priority. This work evaluated the behavior of a foamed material based on biopolymers under the ISO 14855‐2: 2007 standard under simulated natural environmental conditions and its ecotoxic potential of the material residues in the growth of seeds Phaseolus vulgaris. A percentage of biodegradation was obtained in the TPS/PLA samples: 84.7 ± 0.3%; 0% MG: 89.1 ± 0.4%; 2% MG: 82.4 ± 0.4%; 3% MG: 82.0 ± 0.%1; 6% MG: 81.0 ± 0.3%; TPSEG: 66.7 ± 2.4%, and TPSE: 62.9 ± 1.0%; having microcrystalline cellulose as a control sample. CH stretch bands were identified at 728 cm–1 related to PBAT vibration that remained constant in the samples containing PHA, evidencing that this material is not an alternative to elaborate foamed materials to improve their biodegradation. Protein‐based samples increase their biodegradation rate, while based samples PHA remain resilient over time due to the blend of the polymer and the presence of PLA (1437.5 cm–1). The low or high decomposition of the material in weight loss corroborated this behavior of both blends. Regarding the ecotoxicity of the samples, there was no significant difference. [ABSTRACT FROM AUTHOR]

In recent years, extensive laboratory-scale research has focused on the biofilm formation, leaching, and migration of organic chemical compounds from plastic pipes into drinking water. This research has been conducted on an existing distribution network in three rural villages near the dead ends to study the small diameter pipes associated with stagnant or low flow conditions. The distribution network was constructed more than ten years ago using unplasticized polyvinyl chloride pipes. Samples of water, soil, and aged pipes have been collected and tested in the laboratory. Results showed a heavy biofilm formed on the inner surfaces of the uPVC pipes. The biofilm has resulted in high concentrations of trihalomethanes, total organic carbon, and PAHs in the drinking water. The predominant PAHs were the acenaphthylene followed by the naphthalene, while no PAHs have detected at the source. The SEM images showed deterioration of pipe walls, swelled parts, and pores. The EDX confirms the migration of some elements including O, Cl, Ca, Ti, Mg, Fe and K due to the biodegradation of the pipe material and the Ca/Zn stabilizers. However, PAHs released from the plastic pipes into the flowing water are caused by metabolic activities. In addition, results showed that the surrounding soil has classified as having low organic content. Hence, uPVC pipes need protection or change in the manufacturing processes to reduce their hazards in distribution networks over time. [ABSTRACT FROM AUTHOR]

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India accumulates 5.6 million tonnes of plastic waste every year, out of which 66% is the mixed waste polybags and pouches used for food packaging. Especially, the single‐use cups, made up of polystyrene, are not generally recycled as their process is expensive and tedious. On the other hand, biodegradable composite materials on biodegradation and composting act as fertilizers. The applicability of these biodegradable packaging materials is less in the industries as they lack mechanical barrier properties compared with plastic packaging materials. Ultrasonication is one such technology that can result in the successful enhancement of various properties. In ultrasonication, the amplitude was changed to 20%, 40%, and 60%, and time of ultrasonication was varied as 2, 4, 8, and 16 min. Mechanical properties such as tensile strength (31.38 N) and puncture strength (13.35 N) showed improvement. Other important properties such as density increased, whereas the water vapor transmission rate of biodegradable cup samples was decreased. Novelty impact statement: The developed composite biodegradable cup with ultrasonication has good mechanical properties. The developed biodegradable cup can be used as a single‐use food server, thus reducing the use of plastic cups in the food industry. [ABSTRACT FROM AUTHOR]

The development of new biodegradable polymers has increased in the last few years. Typically, the standards describe that 130 days are needed for percentage of biodegradation determination. Therefore, this work presents the use of a LSTM neural network architecture to predict the biodegradation percentage value and decrease the number of testing days. The developed network was able to predict biodegradation values with MAPE from 7.6% to 16.99% between standard test and predicted values. Furthermore, the model was able to forecast the material biodegradability with 40 test days, which is 90 days before the 130 days described in the standards. The main contribution of this development is the decreasing of the total test time allowing an acceleration in new materials development. A complete automated prototype was developed and it is available to industry and institutions at SENAI Institute of Innovation in Polymer Engineering (ISI-POL) at São Leopoldo/RS - Brasil. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, the impact of different ratios of castor oil (CO) and polycarbonate diol (PCDL) mixed soft segments, as well as the introduction of sodium 2-[(2-aminoethyl)amino]ethanesulphonate (AAS-Na) salt, on the biodegradable waterborne polyurethane (WPU) was investigated. Firstly, various waterborne polyurethanes with different mixed soft segments were prepared by adjusting the ratios of castor oil and polycarbonate diol. Subsequently, varying amounts of AAS-Na salt were introduced to assess their influence on the polymer properties. The results indicated that the ratio of CO to PCDL significantly affected the mechanical properties and biodegradability of WPU. As the ratio decreased from 10:0 to 6:4, the tensile strength of WPU films decreased from 18 MPa to 11 MPa, while the elongation at break increased from 56 % to 258 %. Furthermore, the addition of AAS salt improved the water absorption and biodegradation rate of the material. When the ratio of CO to PCDL within the system is 10:0 and the molar content of AAS-Na is 20 mol%, the sample exhibits optimal water absorption of 132.12 % after 48 h and biodegradability of 30.58 % after 28 days. The degradation mechanism was preliminarily explored using Fourier-transform infrared spectroscopy. In conclusion, by adjusting the ratios of castor oil, polycarbonate diol, and AAS salt, a series of biodegradable waterborne polyurethanes with excellent performance were obtained. This study demonstrates the feasibility of developing biodegradable packaging materials using bio-based waterborne polyurethanes as the main component. [ABSTRACT FROM AUTHOR]