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For the increasingly serious software protection problem, the software protection technique based on virtual machine is analyzed, studied and improved, and thus a new software protection technique based on improved virtual machine is proposed. The proposal uses virtual junk code sequence and virtual instruction transformation technique, improves the virtual instruction system of original virtual machine, and hence increases complexity and confusion for virtual machine execution and has the advantages of high anti-reversing, tamper-proof and anti cracking. Experimental analysis proves that the improved virtual machine protection technique outperforms other virtual machine protection techniques. [ABSTRACT FROM AUTHOR]

Aerobic granular sludge can be classified as a type of self-immobilized microbial consortium, consisting mainly of aerobic and facultative bacteria and is distinct from anaerobic granular methanogenic sludge. Aerobic granular technology has been proposed as a promising technology for wastewater treatment, but is not yet established as a large-scale application. Aerobic granules have been cultured mainly in sequenced batch reactors (SBR) under hydraulic selection pressure. The factors influencing aerobic granulation, granulation mechanisms, microbial communities and the potential applications for the treatment of various wastewaters have been studied comprehensively on the laboratory-scale. Aerobic granular sludge has shown a potential for nitrogen removal, but is less competitive for the high strength organic wastewater treatments. This technology has been developed from the laboratory-scale to pilot scale applications, but with limited and unpublished full-scale applications for municipal wastewater treatment. The future needs and limitations for aerobic granular technology are discussed. [ABSTRACT FROM AUTHOR]

Accumulation of formate to millimolar levels was observed during the growth of Methanobacterium formicicum species on H−CO. Hydrogen was also produced during formate metabolism by M. formicicum. The amount of formate accumulated in the medium or the amount H released in gas phase was influenced by the bicarbonate concentration. The formate hydrogenlyase system was constitutive but regulated by formate. When methanogenesis was inhibited by addition of 2-bromoethane sulfonate, M. formicicum synthesized formate from H plus HCOor produced H from formate to a steady-state level at which point the Gibbs free energy (ΔG′) available for formate synthesis or H production was approximately -2 to -3 kJ/reaction. Formate conversion to methane was inhibited in the presence of high H pressure. The relative rates of conversion of formate and H were apparently controlled by the ΔG′ available for formate synthesis, hydrogen production, methane production from formate and methane production from H. Results from C-tracer tests indicated that a rapid isotopic exchange between HCOO and HCOoccurred during the growth of M. formicicum on H−CO. Data from metabolism of C-labelled formate to methane suggested that formate was initially split to H and HCOand then subsequently converted to methane. When molybdate was replaced with tungstate in the growth media, the growth of M. formicicum strain MF on H−CO was inhibited although production of methane was not Formate synthesis from H was also inhibited. [ABSTRACT FROM AUTHOR]

Two types of methanogenic granules capable of high chemical oxygen demand removal rates were developed in laboratory-scale upflow reactors at 35° C. One granule type (R-granules) had a rod-type Methanothrix-like species as the predominant species whereas the other (F-granules) had a filament-type M. soehngenii-like acetate-utilizer as the predominant species. These two types of granules were compared in terms of operational performance, physical-chemical characteristics and microbial population. The R-granules had a higher density [65-70 vs 39-43 g suspended solids (SS)/l], specific gravity (1.03 vs 1.01) and specific volumetric methane production rate (180 vs 120 l CH/l granules per day) than the F-granules. Acetate, propionate and butyrate degraders in both types of granules had similar specific growth rates. The most probable number enumeration indicated that both types of granule had the same population levels (cells/g SS) in terms of methanogens (H-CO-, formate- and acetate-utilizing) and syntrophic acetogens. Hydrolytic-fermentative bacteria were present in greater number in the F-granules than in the R-granules. The R-granules had a higher cell density than the F-granules. The differences in operational performance were due mainly to their different microbial composition, especially the predominant acetate-utilizing methanogens in the granules. The long-filamentous M. soehngenii-like rods in the F-granules appeared to be responsible for their lower density and large-sized granules. [ABSTRACT FROM AUTHOR]

Two types of mesophilic methanogenic granules (R- and F-granules) were developed on different synthetic feeds containing acetate, propionate and butyrate as major carbon sources and their metabolic properties were characterized. The metabolic activities of granules on acetate, formate and H-CO were related to the feed composition used for their development. These granules performed a reversible reaction between H production from formate and formate synthesis from H plus bicarbonate. Both types of granules exhibited high activity on normal and branched volatile fatty acids with three to five carbons and low activity on ethanol and glucose. The granules performed a reversible isomerization between isobutyrate and butyrate during butyrate or isobutyrate degradation. Valerate and 2-methylbutyrate were produced and consumed during propionate-butyrate degradation. The respective apparent K (m m) for various substrates in disrupted R- and F-granules was: acetate, 0.43 and 0.41; propionate, 0.056 and 0.038; butyrate, 0.15 and 0.19; isobutyrate, 0.12 and 0.19; valerate, 0.15 and 0.098. Both granules had an optimum temperature range from 40 to 50° C for H-CO and formate utilization and 40° C for acetate, propionate and butyrate utilization and a similar optimum pH. [ABSTRACT FROM AUTHOR]

The microbial species composition of methanogenic granules developed on an acetate-propionate-butyrate mixture was characterized. The granules contained high numbers of adhesive methanogens (10/g dry weight) and butyrate-, isobutyrate-, and propionate-degrading syntrophic acetogens (10/g dry weight), but low numbers of hydrolytic-fermentative bacteria (10/g dry weight). Prevalent methanogens in the granules included: Methanobacterium formicicum strain T1N and RF, Methanosarcina mazei strain T18, Methanospirillum hungatei strain BD, and a non-filamentous, bamboo-shaped rod species, Methanothrix/Methanosaeta-like strain M7. Prevalent syntrophic acetogens included: a butyrate-degrading Syntrophospora bryantii-like strain BH, a butyrate-isobutyrate degrading non-spore-forming rod, strain IB, a propionate-degrading sporeforming oval-shaped species, strain PT, and a propionate-degrading none-spore-forming sulfate-reducing rod species, strain PW, which was able to grow syntrophically with an H-utilizing methanogen. Sulfate-reducing bacteria did not play a significant role in the metabolism of H, formate, acetate and butyrate but they were involved in propionate degradation. [ABSTRACT FROM AUTHOR]

• Nanoplastics (NPs) are currently less-explored compared to microplastics (MPs). • Co-transport mechanisms of NPs with bacteria and viruses have been proposed. • Aging and aggregation characteristics of NPs have been assessed. • DPSIR framework describes the relationships between NPs, ecosystems and humans. • Further studies should focus on naturally weathered NPs. Tiny plastic particles considered as emerging contaminants have attracted considerable interest in the last few years. Mechanical abrasion, photochemical oxidation and biological degradation of larger plastic debris result in the formation of microplastics (MPs, 1 μm to 5 mm) and nanoplastics (NPs, 1 nm to 1000 nm). Compared with MPs, the environmental fate, ecosystem toxicity and potential risks associated with NPs have so far been less explored. This review provides a state-of-the-art overview of current research on NPs with focus on currently less-investigated fields, such as the environmental fate in agroecosystems, migration in porous media, weathering, and toxic effects on plants. The co-transport of NPs with organic contaminants and heavy metals threaten human health and ecosystems. Furthermore, NPs may serve as a novel habitat for microbial colonization, and may act as carriers for pathogens (i.e., bacteria and viruses). An integrated framework is proposed to better understand the interrelationships between NPs, ecosystems and the human society. In order to fully understand the sources and sinks of NPs, more studies should focus on the total environment, including freshwater, ocean, groundwater, soil and air, and more attempts should be made to explore the aging and aggregation of NPs in environmentally relevant conditions. Considering the fact that naturally-weathered plastic debris may have distinct physicochemical characteristics, future studies should explore the environmental behavior of naturally-aged NPs rather than synthetic polystyrene nanobeads. [ABSTRACT FROM AUTHOR]

Larvae of Zophobas atratus (synonym as Z. morio , or Z. rugipes Kirsch, Coleoptera: Tenebrionidae) are capable of eating foams of expanded polystyrene (EPS) and low-density polyethylene (LDPE), similar to larvae of Tenebrio molitor. We evaluated biodegradation of EPS and LDPE in the larvae from Guangzhou, China (strain G) and Marion, Illinois, U.S. (strain M) at 25 °C. Within 33 days, strain G larvae ingested respective LDPE and PS foams as their sole diet with respective consumption rates of 58.7 ± 1.8 mg and 61.5 ± 1.6 mg 100 larvae−1d−1. Meanwhile, strain M required co-diet (bran or cabbage) with respective consumption rates of 57.1 ± 2.5 mg and 30.3 ± 7.7 mg 100 larvae−1 d−1. Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and thermal gravimetric analyses indicated oxidation and biodegradation of LDPE and EPS in the two strains. Gel permeation chromatography analysis revealed that strain G performed broad depolymerization of EPS, i.e., both weight-average molecular weight (M w) and number-average molecular weight (M n) of residual polymers decreased, while strain M performed limited extent depolymerization, i.e., M w and M n increased. However, both strains performed limited extent depolymerization of LDPE. After feeding antibiotic gentamicin, gut microbes were suppressed, and M w and M n of residual LDPE and EPS in frass were basically unchanged, implying a dependence on gut microbes for depolymerization/biodegradation. Our discoveries indicate that gut microbe-dependent LDPE and EPS biodegradation is present within Z. atratus in Tenebrionidae, but that the limited extent depolymerization pattern resulted in undigested polymers with high molecular weights in egested frass. Image 1 • Zophobas atratus eat low-density polyethylene (LDPE) and expanded polystyrene (EPS) foams. • Larvae from two sources biodegraded LDPE via limited extent depolymerization. • Larvae from different sources biodegraded EPS via broad or limited extent depolymerization. • Antibiotics inhibited depolymerization of LDPE and EPS, indicating gut-microbial dependence. Major findings are that first demonstrated depolymerization/biodegradation of LDPE and confirmed biodegradation of EPS in Zophobas atratus larvae from two different sources; verified gut-microbe dependent LDPE and EPS degradation; and discovered two different depolymerization patterns during plastic biodegradation. [ABSTRACT FROM AUTHOR]

The biodegradation of polychlorinated biphenyls (PCBs) occurs slowly when the degrading bacteria enter a low activity state, such as a viable but nonculturable (VBNC) state, under unfavorable environmental conditions. The introduction of resuscitation-promoting factor (Rpf) can re-activate VBNC bacteria. This study tested the feasibility of enhancing PCB biodegradation via supplementing Rpf in liquid culture and soil microcosms inoculated with Rhodococcus biphenylivorans strain TG9T. Exogenous Rpf resuscitated TG9T cells that had previously entered the VBNC state after 90 d of nutrient starvation, resulting in the significantly enhanced degradation of PCB by 24.3% over 60 h in liquid medium that originally contained 50 mg L−1 Aroclor 1242. In soil microcosms containing 50 mg kg−1 Aroclor 1242 and inoculated with VBNC TG9T cells, after 49 d of supplementation with Rpf, degradation efficiency of PCB reached 34.2%, which was significantly higher than the control. Our results confirmed that exogenous Rpf resuscitated VBNC TG9T cells by stimulating endogenous expression of rpf gene orthologs. The enhanced PCB-degrading capability was likely due to the increased cell numbers and the strong expression of PCB catabolic genes. This study demonstrated the role of Rpf in enhancing PCB degradation via resuscitating PCB-degrading bacteria, indicating a promising approach for the remediation of PCB contamination. Image 1 • VBNC state was studied for Rhodococcus biphenylivorans strain TG9T. • Rpf resuscitated VBNC TG9T cells and enhanced PCB biodegradation. • Exogenous Rpf stimulated endogenous expression of rpf and PCB catabolic genes. • Results highlight the feasibility of enhancing aerobic PCB degradation using Rpf. Results highlight the role of Rpf in enhancing PCB degradation via resuscitating PCB-degrading bacteria, indicating a promising approach for the remediation of PCB contamination. [ABSTRACT FROM AUTHOR]

Accumulation of plastic debris in the environment is a matter of global concern. As plastic ages, it generates microplastic (MP) particles with high mobility. Understanding how MPs are generated is crucial to controlling this emerging contaminant. In this study, we utilized high-density polyethylene (HDPE) plastic gauze, collected from urban settings, as a representative example of plastic waste. The plastic gauze was subjected to various aging conditions, including freeze-thaw cycling, mechanical abrasion, and UV irradiation. Following aging, the plastic gauze was rinsed with water, and the number of generated MPs were quantified. It was found that aged plastic gauze generated up to 334 million MP particles per m2 (> 10 µm) during rinsing, a number two orders of magnitude higher than unaged plastic. Fragmentation occurred in two dimensions for bulk MPs of all morphotypes. However, specific aging approaches (i.e., mechanical abrasion and UV irradiation) generated spheres and fibers via pseudo-3D fragmentation. Additionally, changes in molecular weight, size distribution, and surface oxidation characteristics unveiled a complex pattern (i.e., irregular changes with exposure time). This complexity underscores the intricate nature of plastic debris aging processes in the environment. [Display omitted] • Field collected HDPE plastic gauze was subjected to aging experiments. • Plastic gauze generated millions of MPs per m2 following aging and water rinsing. • Molecular weight, size distribution and oxidation characteristics were explored. • Mechanical abrasion and UV irradiation led to different aging characteristics. [ABSTRACT FROM AUTHOR]

Although mulching is a widely used agronomic practice, its effects on the rhizosphere remain poorly understood. Here, we employed amplicon and transcriptomic sequencing to investigate variations in a grapevine rhizosphere system under mulch treatment (rice straw + felt + plastic film). Analyzing 16S and intergenic spacer (ITS) rRNA sequences indicated that the Shannon and Simpson indices of the bacterial and fungal communities increased markedly under mulch treatment. The bacterial and fungal compositions varied significantly between the control and mulch treatments. Mulching enriched for potentially beneficial microbes that confer disease resistance to plants or participate in nitrogen metabolism (Kaistobacter, Ammoniphilus, Lysobacter, Ammoniphilus, Alicyclobacillus, Aquicella, Nitrospira, Chaetomium, and Microascus), whereas more potentially pathogenic microbes (Fusarium and Gibberella) were detected in the control. Moreover, certain bacteria and fungi exhibited different correlations with the root transcriptome functions of the MEBlue module. The complexity of the bacterial and fungal co-occurrence networks increased with higher node numbers, positive and negative links after mulching. Following mulching, the rhizosphere showed elevated pH, organic matter, and catalase activities, and decreased sucrase and cellulase and β-glucosidase activities. Our results provide comprehensive data showing how a grapevine rhizosphere system responded to mulching treatment and shed important insight into mulching practices for fruit trees. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) with different physical-chemical properties are considered as vectors for the propagation of microbes in aquatic environments. It remains unclear how plastic types impact on the plastisphere and whether different MPs spread microbes more rapidly than natural materials in microbes across distinct water bodies as proposed previously. We used in-situ incubation to investigate the microbes attached on MPs of polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC), versus that on two natural microcarriers (quartz sands and bamboo) during the travel from aquaculture ponds with impacted by fish farming to adjacent freshwater stream. The results showed that the microbial communities on the carriers were shaped not only by environmental conditions, which were primary determinants but also by carrier types. All the tested plastics did not carry more microbes than the natural carriers during the journey. The biofilm community composition on PVC is distinct from that on PE and PP MPs and natural carriers. The plastisphere of PE and PP kept microbial proportions as natural materials did but PVC retained less than nature materials. Bamboo carried more potential pathogens than plastic polymers and quartz. The results indicated that the communities of plastisphere is polymer-type dependent, and, compared with the natural materials, MPs did not show enhanced propagation of microbes, including pathogens, cross distinct environments. [Display omitted] ● Biofilms on plastics and natural media were tested across aquaculture ponds to stream. ● Environmental factor primarily governs microbial communities rather than media types. ● PVC lost more microbes than PE or PP after the transfer. ● Microplastics did not carry more microbes across waterbodies than quartz or bamboo. ● Reassessing plastics as microbe carriers requires considering nutrients and salinity. [ABSTRACT FROM AUTHOR]

Organo-mineral interaction is an important mechanism affecting the fate of natural organic matter in the environment. Field discoveries since 2014 report a novel type of organo-mineral interaction, where "recalcitrant" plastic polymers either physically or chemically attach onto or fuse into host rocks or sediments. During our previous field observation in 2022, it was reported that weathered low-density polyethylene (LDPE) plastic films were chemically attached onto sedimentary rocks. It was hypothesized that sunlight irradiation may have triggered chemical interactions following physical attachment of plastic film onto rock surfaces. In this study, we tested this hypothesis through accelerated aging experiments. Specifically, we first explored the interaction mechanisms between low-density polyethylene film and crushed sedimentary rock powders, including sandstone, shale, limestone, and ironstone, through accelerated UV irradiation ranging from 0 to 168 h. Subsequently, we conducted experiments using the plastic film and consolidated shale rocks. We found that chemical binding took place after 48 h of UV irradiation equivalent to 35 days of exposure of plastic film to sunlight on the land surface. The organo-mineral interaction process started with the surface oxidation of plastic film leading to the generation of carbonyl and ether groups. After that, irreversible mineral binding occurred. Visualization of the plastic films following the aging experiments showed that mineral particles were incorporated within the polymer instead of surface attachment. Organo-mineral interaction mechanisms between LDPE film and sedimentary rocks were further explored via multiple approaches including XPS, STEM-EELS, TOF-SIMS, and theoretical calculations. Multiple lines of evidence suggested binding mechanisms for this process, including the formation of chemical bonds such as Si-O-C, corroborating well with our previously reported field findings. The findings of this study offer robust evidence that natural weathering processes, such as sunlight irradiation, can initiate chemical reactions between plastic and rock materials, deepening our understanding of plastic pollution dynamics within the geological context. [Display omitted] • Organo-mineral interactions between LDPE and sedimentary rocks were explored. • Mechanisms were explored via XPS, STEM-EELS, TOF-SIMS, and DFT calculations. • UV equivalent to 35 days' exposure to sunlight triggered chemical binding. • Results from this study provided robust evidence that plastic can react with rock. [ABSTRACT FROM AUTHOR]

A bacterial strain C21 isolated from constructed wetland soil was identified as Arthrobacter sp. based on 16S rRNA gene sequence analysis and physio-biochemical characteristics and was capable of utilizing di- n-butyl phthalate (DBP) as a carbon and energy source for growth. Strain C21 can also utilize other phthalates (PAEs) up to a molecular weight of 390.56 and phthalic acid (PA). The biodegradability of these compounds decreased with the increase in the length of phthalate alkyl chains and molecular weight. Kinetic analysis indicated that the strain C21 cell growth on DBP fitted well with Haldane-Andrews' model ( R > 0.98) with μ, K, and K of 0.12/h, 4.2 mg/L, and 204.6 mg/L, respectively. When the initial DBP concentration was lower than 100 mg/L, DBP biodegradation reaction fitted with the first-order kinetics. The results suggested that Arthrobacter strain C21 played an active role in the bioremediation of the wetland contaminated with phthalates. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution is widely spread in oceans, freshwater, and terrestrial environments but MPs in mountainous headwater ecosystem are rarely reported. This study focuses on the headwater of Yangtze tributaries of the Hindu Kush-Himalayan (HKH) region. Five streams at elevations of 900 to 3300 m were selected to investigate the distribution of MPs in water and sediments across altitudes. MPs were found in all water and sediment samples from top stream zone nearly in absence of anthropogenic activity, low anthropogenic zone, and high anthropogenic zone, increased from 12–54, 81–185 to 334–847 items/L, and 2–35, 26–84 to 124–428 items/kg, respectively. This elevation-dependent MP distribution indicated that as elevation decreased, anthropogenic activities intensified and increased MPs input and their abundance, size, and diversity. Notably, hydraulic projects, such as damming, were identified as potential barriers to the migration of MPs downstream. Microbiome analyses revealed the presence of bacterial genes associated with plastic biodegradation in all sediment samples. The study indicates that Shangri-la mountainous streams have been polluted with MPs for years with potential risk of generation of nano-sized particles via natural fragmentation and biodegradation, and thus raises concern on MPs pollution in headwaters streams in mountainous regions. [Display omitted] • Anthropogenic and biological activities elevate MPs pollution in mountain headwaters. • MPs pollution observed in top and increased towards downstream. • Hydraulic projects e.g. damming prevent MPs migration to downstream. • Genes of 15 bacterial genera associated with plastic degradation was found in sediments. • MPs have symptoms of further degradation into more ecologically risky nanoplastics. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) is the most productive plastic product and includes three major polymers including high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) variation in the PE depends on the branching of the polymer chain and its crystallinity. Tenebrio obscurus and Tenebrio molitor larvae biodegrade PE. We subsequently tested larval physiology, gut microbiome, oxidative stress, and PE degradation capability and degradation products under high-purity HDPE, LLDPE, and LDPE powders (<300 μm) diets for 21 days at 65 ± 5% humidity and 25 ± 0.5 °C. Our results demonstrated the specific PE consumption rates by T. molitor was 8.04–8.73 mg PE ∙ 100 larvae−1⋅day−1 and by T. obscurus was 7.68–9.31 for LDPE, LLDPE and HDPE, respectively. The larvae digested nearly 40% of the ingested three PE and showed similar survival rates and weight changes but their fat content decreased by 30–50% over 21-day period. All the PE-fed groups exhibited adverse effects, such as increased benzoquinone concentrations, intestinal tissue damage and elevated oxidative stress indicators, compared with bran-fed control. In the current study, the digestive tract or gut microbiome exhibited a high level of adaptability to PE exposure, altering the width of the gut microbial ecological niche and community diversity, revealing notable correlations between Tenebrio species and the physical and chemical properties (PCPs) of PE-MPs, with the gut microbiome and molecular weight change due to biodegradation. An ecotoxicological simulation by T.E.S.T. confirmed that PE degradation products were little ecotoxic to Daphnia magna and Rattus norvegicus providing important novel insights for future investigations into the environmentally-friendly approach of insect-mediated biodegradation of persistent plastics. [Display omitted] • Mealworms biodegrade high-density, linear low-density and low-density polyethylene. • Gut flora adapts to PE types by changing their niche width and diversity. • Molecular weights are a key factor influencing the gut microbiome. • The physiological and oxidative stress responses varied between larval species. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET or polyester) is a commonly used plastic and also contributes to the majority of plastic wastes. Mealworms (Tenebrio molitor larvae) are capable of biodegrading major plastic polymers but their degrading ability for PET has not been characterized based on polymer chain size molecular size, gut microbiome, metabolome and transcriptome. We verified biodegradation of commercial PET by T. molitor larvae in a previous report. Here, we reported that biodegradation of commercial PET (M w 29.43 kDa) was further confirmed by using the δ13C signature as an indication of bioreaction, which was increased from − 27.50‰ to − 26.05‰. Under antibiotic suppression of gut microbes, the PET was still depolymerized, indicating that the host digestive enzymes could degrade PET independently. Biodegradation of high purity PET with low, medium, and high molecular weights (MW), i.e. , M w values of 1.10, 27.10, and 63.50 kDa with crystallinity 53.66%, 33.43%, and 4.25%, respectively, showed a mass reduction of > 95%, 86%, and 74% via broad depolymerization. Microbiome analyses indicated that PET diets shifted gut microbiota to three distinct structures, depending on the low, medium, and high MW. Metagenome sequencing, transcriptomic, and metabolic analyses indicated symbiotic biodegradation of PET by the host and gut microbiota. After PET was fed, the host's genes encoding degradation enzymes were upregulated, including genes encoding oxidizing, hydrolyzing, and non-specific CYP450 enzymes. Gut bacterial genes for biodegrading intermediates and nitrogen fixation also upregulated. The multiple-functional metabolic pathways for PET biodegradation ensured rapid biodegradation resulting in a half-life of PET less than 4 h with less negative impact by PET MW and crystallinity. [Display omitted] • High-crystallinity PET biodegradation was confirmed by testing change of δ13C. • Depolymerization is independent of gut microbes. • Polymer molecular size influences degradation rates. • Gut microbiomes synergistically biodegrade intermediates and provide nitrogen sources. • Upregulation of host genes for PET depolymerization and metabolism. [ABSTRACT FROM AUTHOR]

It is widely understood that microplastics (MPs) can induce various biological stresses in macroinvertebrates that are incapable of biodegrading plastics. However, the biodegradation and physiological responses of plastic-degrading macroinvertebrates toward MPs of different degradability levels remain unexplored. In this study, Tenebrio molitor larvae (mealworms) were selected as a model of plastics-degrading macroinvertebrate, and were tested against three common plastics of different degradability rankings: polyvinyl chloride (PVC), polystyrene (PS), and polylactic acid (PLA) MPs (size <300 μm). These three MPs were biodegraded with the rate sequence of PLA > PS > PVC, resulting in a reversed order of negative physiological responses (body weight loss, decreased survival, and biomass depletion) of mealworms. Simultaneously, the levels of reactive oxygen species (ROS), antioxidant enzyme activities, and lipid peroxidation were uniformly increased as polymer degradability decreased and intermediate toxicity increased. PVC MPs exhibited higher toxicity than the other two polymers. The oxidative stresses were effectively alleviated by supplementing co-diet bran. The T. molitor larvae fed with PLA plus bran showed sustainable growth without an increase in oxidative stress. The results provide new insights into the biotoxicity of MPs on macroinvertebrates and offer comprehensive information on the physiological stress responses of plastic-degrading macroinvertebrates during the biodegradation of plastics with different degradability levels. [Display omitted] • Microplastics (MPs) degradation rate by mealworms with sequence of PLA > PS > PVC. • Physiological responses were dependent on polymer degradability and intermediate toxicity. • Supplementing nutrient-rich co-diets alleviated oxidative stress by MPs. • Nanoplastics were not detected in frass after microplastics biodegradation. [ABSTRACT FROM AUTHOR]

An innovative approach is developed to utilize the frass of mealworms (Tenebrio molitor Linnaeus 1758) for producing dye-removal biochar. Agricultural waste wheat straw (WS) was tested as feedstock versus wheat bran (WB) to rear mealworms for the production of insect biomass. Mealworms on WS grew at a slightly slower rate than those grown on WB for 32 days with ∼40% lignin removed at 25 °C. Biochars were generated using the frass of mealworms via pyrolysis. The best adsorption performance for three dyes, especially malachite green, a cationic dye, was the biochar of WS frass at 800 °C; it had better capacity (1738.6 mg/g) compared with the frass fed with bran, raw WS and raw WB as well as those reported in the literature. Adsorption of malachite green fits the Langmuir isotherm and the pseudo second order kinetic model, mainly due to chemisorption and electrostatic interaction. Our results demonstrated that the WS can be utilized to rear mealworms, and that frass of mealworms is an excellent raw material for generating high-efficiency bioadsorbents. Image 10384 • Mealworms lived on WS as diet and digested 39.17% of the consumed WS over 32 days. • Biochar generated from WS fed frass had highest adsorption capacity than others. • Adsorption isotherm fits Langmuir model, kinetics fits pseudo-second order reaction. • Adsorption was mainly due to chemisorption and electrostatic interaction. • Frass of mealworms can provide raw materials to generate high quality bioadsorbents. [ABSTRACT FROM AUTHOR]

Microplastic pollution has become emerging environmental concern around world. The wastewater treatment plants (WWTPs) are attributed to a major pathway for microplastics (MPs) to enter into aquatic environment. To understand the fate and control strategies of MPs in WWTPs, we investigated MPs at a full-scale WWTP, Eastern China, with two parallel wastewater treatment systems, i.e. oxidation ditch (OD) and membrane bioreactor (MBR) for case study. The influent MPs consisted of polyethylene terephthalate (PET, 47%), polystyrene (PS, 20%), polyethylene (PE, 18%) and polypropylene (PP, 15%). MP morphotypes dominated in fragments (65%) and fibers (21%), which mainly were PET, with limited films (12%) and foams (2%). Typical plastic microbeads were not observed. The dominant size of MPs was >500 μm (40%) and 62.5–125 μm (29%). MP concentrations increased across the treatment systems depends on facility of treatment process. Influent MPs were removed by 99.5% in MBR system versus 97% in OD system on the basis of plastic mass while 82.1% versus 53.6% on MP number. The removed MPs accumulated in sludge phase. MBR system has much higher MP removal efficiency than OD system, likely due to membrane filtration. The results suggest that the source control of MPs by eliminating MP fibers from laundry facilities, banning use of plastic microbeads, Styrofoam products and plastic bags and properly selecting WWTP treatment unit could significantly reduce the mass and number of MPs from WWTPs. Image 1 • Microplastics (MP) numbers increased cross oxidation ditch and MBR systems. • MPs belonging to PET, PS, PE and PP dominated in morphotypes of fragments and fibers. • MPs removed from water phase by >97% and accumulated in sludge phase. • MBR was superior in MP removal due to micromembrane filtration. • Strategies for MP source reduction and enhancement of WWTP management are proposed. [ABSTRACT FROM AUTHOR]

Abstract Aquaponics is considered as a promising approach to mass produce both fish meat and vegetable at high rates without discharge pollutants. A novel aquaponics system is proposed to control water quality and enhance nutrition efficiency with high rate immobilized biofilm units, including mass-bio system (MBS) and fiber biofilter (FB), installed between upstream hydroponics units, which are composed of the media filled beds (MFD) and nutrient film technique (NFT), and downstream aquaculture unit for fish rearing. A pilot test was conducted over 130 d to characterize the performance of proposed system which converted residual nutrients from aquaculture unit into ammonium and nitrate at balanced ratio for aquatic plant growth and then removed residual ammonium or/and nitrite to ensue recycled water quality for fish rearing. The kinetics of organic matter removal and nutrient conversion in hydroponics unit and immobilized biofilm units were determined via batch assays over 24 h in the system. The estimated daily pollutant increments for TAN, NO 2 −-N, NO 3 −-N, TN, DTP and TOC in the system were 0.28, 0.17, 0.20, 0.64, 0.56 and 2.19 mg/L, respectively. The results demonstrated that total ammonia nitrogen (TAN), nitrite (NO 2 −-N), nitrate (NO 3 −-N), total nitrogen (TN), dissolved total phosphorus (DTP) and total organic carbon (TOC) were maintained at low levels in the system for a long-term. Aquatic plants in MFD and NFT contributed to the removal of TAN, NO 2 −-N, NO 3 −-N, TN and DTP. The removal efficiencies of MFD versus NFT for TAN were 71.4% vs 43.5% for TAN and 62.5% vs 52.3% for DTP. MBS and FB performed the removal of TAN, NO 2 −-N and TOC. The 24 h removal efficiencies of TAN, NO 2 −-N and TOC were 71.8%, 58.5% and 3.7% for MBS and 15.7%, 7.7% and 27.2% for FB. Graphical abstract Image Highlights • A novel process of aquaponics system combined with immobilized biofilm units was tested at pilot scale. • This system controlled water quality of aquaponics for fish rearing over 130 d. • Aquatic plants in media filled beds showed better nutrient removal than nutrient film technique. • More total ammonia was removed by immobilized biofilm units than hydroponics units. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is a mass-produced fossil-based plastic polymer that contributes to catastrophic levels of plastic pollution. Here we demonstrated that Tenebrio molitor (mealworms) was capable of rapidly biodegrading two commercial PET resins (microplastics) with respective weight-average molecular weight (M w) of 39.33 and 29.43 kDa and crystallinity of 22.8 ± 3.06% and 18 ± 2.25%, resulting in an average mass reduction of 71.03% and 73.28% after passage of their digestive tract, and respective decrease by 9.22% and 11.36% in M w of residual PET polymer in egested frass. Sequencing of 16 S rRNA gene amplicons of gut microbial communities showed that dominant bacterial genera were enriched and associated with PET degradation. Also, PICRUSt prediction exhibited that oxidases (monooxygenases and dioxygenases), hydrolases (cutinase, carboxylesterase and chitinase), and PET metabolic enzymes, and chemotaxis related functions were up-regulated in the PET-fed larvae. Additionally, metabolite analyses revealed that PET uptake caused alterations of stress response and plastic degradation related pathways, and lipid metabolism pathways in the T. molitor larvae could be reprogrammed when the larvae fed on PET. This study provides new insights into gut microbial community adaptation to PET diet under nutritional stress (especially nitrogen deficiency) and its contribution to PET degradation. [Display omitted] • Confirmation of commercial PET biodegradation by Tenebrio molitor. • Minor difference in degradation performance of two PET polymers. • Spiroplasma , Dysgonomonas and Hafnia-Obesumbacterium associated with PET degradation. • Both host and gut microbiota contributed enzyme repertoire to PET degradation. • A plausible mechanism was proposed based on 16 S rRNA and metabolome analyses. [ABSTRACT FROM AUTHOR]

Hypertension is a multifactorial chronic inflammatory disease that leads to cardiac remodeling. A-kinase anchor protein 12 (AKAP12) is a scaffolding protein that has multiple functions in various biological events, including the regulation of vessel integrity and differentiation of neural barriers in blood. However, the role of AKAP12 in angiotensin II (Ang II)-induced cardiac injury remains unclear. In the present study, Ang II infusion reduced AKAP12 expressions in the hearts of wild-type (WT) mice, and AKAP12 knockout (KO) enhanced the infiltration of inflammatory cells. In addition, AKAP12 deletion accelerated Ang II-induced cardiac histologic alterations and dysfunction. Further, AKAP12 −/− aggravated heart failure by promoting the inflammation, oxidative stress, cellular apoptosis, and autophagy induced by Ang II. Furthermore, AKAP12 KO elevated Ang II-induced cardiac fibrosis, as indicated by the following: (1) Masson trichrome staining showed that Ang II infusion markedly increased fibrotic areas of the WT mouse heart, which was greatly accelerated in AKAP12 −/− mice; (2) immunohistochemistry analysis showed increased expression of transforming growth factor β1 (TGF-β1) and α-smooth muscle actin (α-SMA) in the AKAP12 −/− mouse heart; (3) reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) analysis showed increased expression of fibrosis-related molecules in the AKAP12-deficient mouse heart; and (4) Western blot analysis indicated significantly higher upregulation of p-SMAD2/3 in the AKAP12 −/− mouse heart. In vitro, AKAP12 knockdown in HL-1 cells was responsible for TGF-β1-induced inflammation, the generation of reactive oxygen species (ROS), apoptosis, autophagy, and fibrosis. Furthermore, overexpression of AKAP12 reduced fibrosis triggered by TGF-β1 in cells. Overall, our study suggests that fibrosis induced by Ang II may be alleviated by AKAP12 expression through inactivation of the TGF-β1 pathway. [ABSTRACT FROM AUTHOR]