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Biodegradable polylactic acid (PLA) mulch has been developed to replace conventional polyethylene (PE) mulch in agriculture as a response to growing concerns about recalcitrant plastic pollution and the accumulation of microplastics (MPs) in soil. Cadmium is a significant soil pollutant in China. MPs have been shown to adsorb metals. In this study the earthworm Lumbricus terrestris was exposed to either Cd (1.0-100 mg / kg) or MPs (PE and PLA, 0.1-3 % w / w), or a combination of the two, for 28 days. Cd bioavailability significantly decreased in the presence of MPs. In particular, at the end of the experiment, PLA treatments had lower measured Cd concentrations in both earthworms (2.127-29.24 mg / kg) and pore water (below detection limits - 0.1384 mg /L) relative to PE treatments (2.720-33.77 mg / kg and below detection limits - 0.2489 mg / L). In our adsorption experiment PLA MPs adsorbed significantly more Cd than PE MPs with maximum adsorption capacities of 126.0 and 23.2 mg / kg respectively. These results suggest that the PLA MPs reduce earthworm exposure to Cd relative to PE by removing it from solution and reducing its bioavailability.

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INTRODUCTION: The demand for red blood cells (RBCs) is on the rise due to the increasing diagnosis of chronic diseases such as sickle cell anemia, malaria, and thalassemia. Despite many commercial attempts, there are no U.S. FDA-approved artificial RBCs for use in humans. Existing RBC substitutes have employed various strategies to transport oxygen, extend the circulation time, and reduce organ toxicity, but none have replicated the natural protective mechanisms of RBCs, which prevent hemoglobin (Hb) dimerization and heme iron oxidation. Lumbricus terrestris (earthworm) erythrocruorin (LtEc) is a naturally occurring extracellular hemoglobin (Hb) with promising attributes: large molecular diameter (30 nm), high molecular weight (3.6 MDa), low auto-oxidation rate, and limited nitric oxide-scavenging properties. These characteristics make LtEc an ideal candidate as an RBC substitute. However, LtEc has a significant drawback, its short circulatory half-life. To address this issue, we explored thiol-mediated surface PEGylation of LtEc (PEG-LtEc) at varying polyethylene glycol (PEG) surface coverages. Increasing PEG surface coverage beyond 40% destabilizes LtEc into smaller subunits that are 1/12th the size of LtEc. Therefore, we evaluated two PEG surface coverage options: PEG-LtEc-0.2 (20% PEGylation) and PEG-LtEc-1.0 (100% PEGylation). METHODS: We conducted experiments using golden Syrian hamsters with dorsal window chambers and catheters to assess the efficacy of these solutions. We measured microvascular parameters, organ function, cerebral blood flow, circulation time, mean arterial pressure, heart rate, and blood gases and performed histology to screen for toxicity. CONCLUSION: Our findings indicate that both PEG-LtEc molecules offer significant benefits in restoring microvascular parameters, organ function, cerebral blood flow, and circulation time compared to LtEc alone. Notably, PEG-LtEc-1.0 showed superior microvascular perfusion, although it exhibited a higher rate of auto-oxidation compared to PEG-LtEc-0.2. These results underscore the advantages of PEGylation in terms of tissue perfusion and organ health while highlighting its limitations.

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Microplastic (MP) pollution constitutes an emerging type of pollution threatening both aquatic and terrestrial ecosystems. The impact on aquatic ecosystems has been extensively studied, but the effect on terrestrial ecosystems and their inhabitants is mostly underexplored. In this study, we explored the effect of MP pollution on gut bacterial microbiome of endogeic (Aporrectodea caliginosa) and anecic (Lumbricus terrestris) earthworms. The experiments were performed in sandy soil with 0.2% of low-density polyethylene MPs (LDPE MPs). We observed that the endogeic earthworms had 100% survival, while anecic earthworms survived 25 days in the control (i.e. in absence of MPs) and 21 days in the treatment with LDPE MPs. The main driver of shifts in the diversity and composition of the bacterial communities in the gut of tested earthworms was the lifestyle of the worms, followed by the presence of MPs. The bacterial microbiome diversity was significantly different among the two types of earthworms, and the highest bacterial diversity was found in the gut of the endogeic earthworms. The effect of MPs on gut bacterial microbiome was clearly observed in the changes in the relative abundance of several phyla and families of the bacterial communities in both types of earthworms, although it was most evident in the anecic earthworms. The Actinobacteriota, Proteobacteria, and Firmicutes were the main groups enhanced in the MP treatments, suggesting enrichment of the bacterial communities with potential plastic degraders.

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Haemorrhagic shock is a leading cause of death worldwide. Blood transfusions can be used to treat patients suffering severe blood loss but donated red blood cells (RBCs) have several limitations that limit their availability and use. To solve the problems associated with donated RBCs, several acellular haemoglobin-based oxygen carriers (HBOCs) have been developed to restore the most important function of blood: oxygen transport. One promising HBOC is the naturally extracellular haemoglobin (i.e. erythrocruorin) of Lumbricus terrestris (LtEc). The goal of this study was to maximise the portability of LtEc by lyophilising it and then testing its stability at elevated temperatures. To prevent oxidation, several cryoprotectants were screened to determine the optimum formulation for lyophilisation that could minimise oxidation of the haem iron and maximise recovery. Furthermore, samples were also deoxygenated prior to storage to decrease auto-oxidation, while resuspension in a solution containing ascorbic acid was shown to partially reduce LtEc that had oxidised during storage (e.g. from 42% Fe3+ to 11% Fe3+). Analysis of the oxygen equilibria and size of the resuspended LtEc showed that the lyophilisation, storage, and resuspension processes did not affect the oxygen transport properties or the structure of the LtEc, even after 6 months of storage at 40 °C. Altogether, these efforts have yielded a shelf-stable LtEc powder that can be stored for long periods at high temperatures, but future animal studies will be necessary to prove that the resuspended product is a safe and effective oxygen transporter in vivo.

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BACKGROUND: Artificial light at night, also referred to as light pollution (LP), has been shown to affect many organisms. However, little is known about the extent to which ecological interactions between earthworms and plants are altered by LP. We investigated the effects of LP on anecic earthworms (Lumbricus terrestris) that come to the surface at night to forage and mate, and on the germination and growth of the invasive and allergenic ragweed (Ambrosia artemisiifolia). In a full factorial pot experiment in the greenhouse, we tested four factors and their interactions: LP (5 lux vs. 0 lux at night), earthworms (two individuals vs. none), plant species (seeding of ragweed only vs. mixed with Phacelia seeds) and sowing depth (seed placed at the surface vs. in 5 cm depth). Data were analysed using Generalized Linear (Mixed) Models and multifactorial ANOVAs with soil parameters as covariates. RESULTS: Light pollution reduced earthworm surface activity by 76% as measured by casting activity and toothpick index; 85% of mating earthworms were observed in the absence of LP. Light pollution in interaction with earthworms reduced ragweed germination by 33%. However, LP increased ragweed height growth by 104%. Earthworms reduced ragweed germination especially when seeds were placed on the soil surface, suggesting seed consumption by earthworms. CONCLUSIONS: Our data suggest that anecic earthworms are negatively affected by LP because reduced surface activity limits their ability to forage and mate. The extent to which earthworm-induced ecosystem services or community interactions are also affected by LP remains to be investigated. If the increased height growth of ragweed leads to increased pollen and seed production, it is likely that the competition of ragweed with field crops and the risks to human health will also increase under LP.

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The erythrocruorin of Lumbricus terrestris (LtEc) is a relatively large macromolecular assembly that consists of at least four different hemoglobin subunits (A, B, C, and D) and four linker subunits (L1, L2, L3, and L4). The complexity and stability of this large structure make LtEc an attractive hemoglobin-based oxygen carrier that could potentially be used as a substitute for donated red blood cells. However, the sequences of the LtEc subunit sequences must be determined before a scalable recombinant expression platform can be developed. The goal of this study was to sequence the L. terrestris genome to identify the complete sequences of the LtEc subunit genes. Our results revealed multiple homologous genes for each subunit (e.g., two homologous A globin genes; A1 and A2), with the exception of the L4 linker. Some of the homologous genes encoded identical peptide sequences (C1 and C2, L1a and L1b), while cDNA and mass spectrometry experiments revealed that some of the homologs are not expressed (e.g., A2). In contrast, multiple sequences for the B, D, L2, and L4 subunits were detected in LtEc samples. These observations reveal novel degeneracy in LtEc and other annelids, along with some new revisions to its previously published peptide sequences.

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Objective To investigate the effect of Lumbricus protein on the phenotypic transformation of corporal cavernosum smooth muscle cells(CCSMC)and erectile function in diabetic erectile dysfunction(DMED)rats.Methods Sixty male SD rats with normal erectile function were randomly divided into a blank group,a model group,a Sildelafil group(5 mg·kg-1),and a Lumbricus protein low-,medium-,and high-dose group(45,90,and 180 mg·kg-1),with 10 rats in each group.The diabetic rat model was established by intraperitoneal injection of Streptozotocin(STZ,50 mg·kg-1)combined with high-fat feed feeding;after 8 weeks,the DMED rat model was prepared by neck injection of Apomorphine(APO,100 μg·kg-1).After successful modeling,the rats were administered with a dose of Apomorphine by gavage once a day for 4 weeks.The blood glucose levels and body mass of rats in each group were measured before modeling,on the third day of modeling,and after 4 weeks of drug administration.The intracavernous pressure(ICP)and carotid artery pressure(MAP)were measured by multi-channel physiological recorder,and the ICP/MAP ratio was calculated.The expressions of contractile markers α-smooth muscle actin(α-SMA),smooth muscle myosin heavy chain(SMMHC)and synthetic markers Collagen I and osteopontin(OPN)in corpus cavernosum were detected by immunohistochemistry.The mRNA expression levels of α-SMA,SMMHC and Collagen I in corpus cavernosum were detected by RT-PCR.The protein expression levels of α-SMA,Desmin,Collagen I and OPN in corpus cavernosum were detected by Western Blot.Results Compared with the blank group,the blood glucose levels of the rats in the model group were significantly increased on the third day of modeling and after 4 weeks of administration(P＜0.01),and the body mass was significantly decreased after 4 weeks of administration(P＜0.01).ICP and ICP/MAP ratio were significantly decreased(P＜0.01).The protein expression levels of α-SMA,SMMHC and Desmin in penile corpus cavernosum were significantly decreased(P＜0.01),and the protein expression levels of Collagen I and OPN were significantly increased(P＜0.01).The mRNA expression levels of α-SMA and SMMHC in corpus cavernosum were significantly decreased(P＜0.01),and the mRNA expression level of Collagen I was significantly increased(P＜0.01).Compared with the model group,there was no significant change in blood glucose and body mass of rats in the administration group(P＞0.05).ICP and ICP/MAP ratio were significantly increased(P＜0.01).The expression levels of α-SMA,SMMHC and Desmin in corpus cavernosum were significantly increased(P＜0.01),while the expression levels of Collagen I and OPN were significantly decreased(P＜0.01).The mRNA expression levels of α-SMA and SMMHC in corpus cavernosum were significantly increased(P＜0.01),and the mRNA expression level of Collagen I was significantly decreased(P＜0.01).Conclusion Lumbricus protein can improve the erectile function of DMED rats,and its mechanism may be related to the inhibition of CCSMC from'contractile'to'synthetic(proliferative)'transformation.

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Microorganisms from L. terrestris gut previously exposed to different types of plastic (PET, LDPE, LLDPE, and PS) were studied to be used as probiotics of earthworms in plastic-contaminated soils (LDPE, LLDPE and recycled mulching film) at mesocosm-scale trials. The most abundant morphotypes with enzymatic capacities of interest were identified. Pseudomonas alkylphenolica (PL4) and Pseudomonas putida (PL5) strains were selected to be used as inoculants using Morus alba leaves as carriers to strengthen the intestinal microbiota of earthworms. Culture (selective cetrimide agar medium) and molecular (qPCR) techniques were used to trace the presence of the inoculum in the intestine of the earthworms. Additionally, a metataxonomic analysis was carried out to study the biodiversity and functionality of the earthworm microbiome, and their measure of survival and weight. Probiotics improved the survival rates of earthworms exposed to plastics, which also increased the abundance of microbial groups of interest in plastic bioremediation tasks.

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Microglia-induced inflammatory signaling and neuronal oxidative stress are mutually reinforcing processes central to the pathogenesis of neurodegenerative diseases. Recent studies have shown that extracts of dried Pheretima aspergillum (Lumbricus) can inhibit tissue fibrosis, mitochondrial damage, and asthma. However, the effects of Lumbricus extracts on neuroinflammation and neuronal damage have not been previously studied. Therefore, to evaluate the therapeutic potential of Lumbricus extract for neurodegenerative diseases, the current study assessed the extract's anti-inflammatory and antioxidant activities in BV2 microglial cultures stimulated with lipopolysaccharide (LPS) along with its neuroprotective efficacy in mouse hippocampal HT22 cell cultures treated with excess glutamate. Lumbricus extract dose-dependently inhibited the LPS-induced production of multiple proinflammatory cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß) and reversed the upregulation of proinflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2). Lumbricus also activated the antioxidative nuclear factor erythroid 2-relayed factor 2/heme oxygenase-1 pathway and inhibited LPS-induced activation of the nuclear factor-κB/mitogen-activated protein kinases/NOD-like receptor family pyrin domain containing 3 inflammatory pathway. In addition, Lumbricus extract suppressed the glutamate-induced necrotic and apoptotic death of HT22 cells, effects associated with upregulated expression of antiapoptotic proteins, downregulation of pro-apoptotic proteins, and reduced accumulation of reactive oxygen species. Chromatography revealed that the Lumbricus extract contained uracil, hypoxanthine, uridine, xanthine, adenosine, inosine, and guanosine. Its effects against microglial activation and excitotoxic neuronal death reported herein support the therapeutic potential of Lumbricus for neurodegenerative diseases.

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Background and Objectives: The ineffective combination of corticosteroids and antibiotics in treating some atopic dermatitis (AD) cases has been concerning. The skin barrier defects in AD ease the colonization of Staphylococcus aureus (S. aureus), which results in a rise in interleukin-31 (IL-31). Lumbricus rubellus (L. rubellus) has shown antimicrobial and antiallergic effects but has not been studied yet to decrease the growth of S. aureus and IL-31 levels in AD patients. This study aimed to analyze the effect of L. rubellus extract in reducing S. aureus colonization, the IL-31 level, and the severity of AD. Materials and Methods: A randomized controlled trial (RCT) (international registration number TCTR20231025004) was conducted on 40 AD patients attending Dermatology and Venereology Polyclinic, Mother and Child Hospital (RSIA), Aceh, Indonesia, from October 2021 to March 2022. AD patients aged 8-16 who had a Scoring Atopic Dermatitis (SCORAD) index > 25, with total IgE serum level > 100 IU/mL, and had healthy weight were randomly assigned into two groups: one received fluocinolone acetonide 0.025% and placebo (control group) and one received fluocinolone acetonide 0.025% combined with L. rubellus extract (Vermint®) (intervention group). The S. aureus colony was identified using a catalase test, coagulase test, and MSA media. The serum IL-31 levels were measured using ELISA assay, while the SCORAD index was used to assess the severity of and improvement in AD. Mean scores for measured variables were compared between the two groups using an unpaired t-test and Mann-Whitney U test. Results: A significant decline in S. aureus colonization (p = 0.001) and IL-31 (p = 0.013) in patients receiving L. rubellus extract was found in this study. Moreover, fourteen AD patients in the intervention group showed an improvement in the SCORAD index of more than 35% (p = 0.057). Conclusions: L. rubellus extract significantly decreases S. aureus colonization and the IL-31 level in AD patients, suggesting its potential as an adjuvant therapy for children with AD.

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Soil microplastic pollution can have negative effects on organisms, including plants, but the underlying mechanisms are not fully understood. We tested whether structural or chemical properties of a microplastic cause its effects on plant above- and belowground growth and whether these effects can be influenced by earthworms. We conducted a factorial experiment in a greenhouse with seven common Central European grassland species. Microplastic granules of the synthetic rubber ethylene propylene diene monomer (EPDM),1 a frequently used infill material of artificial turfs, and cork granules with a comparable size and shape to the EPDM granules were used to test for structural effects of granules in general. To test for chemical effects, EPDM-infused fertilizer was used, which should have contained any leached water-soluble chemical components of EPDM. Two Lumbricus terrestris individuals were added to half of the pots, to test whether these earthworms modify effects of EPDM on plant growth. EPDM granules had a clear negative effect on plant growth, but since cork granules had a negative effect of similar magnitude, with an average decrease in biomass of 37 % in presence of granules, this is likely due to the structural properties of granules (i.e., size and shape). For some belowground plant traits, EPDM had a stronger effect than cork, which shows that there must be other factors playing into the effects of EPDM on plant growth. The EPDM-infused fertilizer did not have any significant effect on plant growth by itself, but it had in interaction with other treatments. Earthworms had an overall positive effect on plant growth and mitigated most of the negative effects of EPDM. Our study shows that EPDM microplastic can have negative effects on plant growth, and that these might be more related to its structural than to its chemical properties.

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BACKGROUND: Lumbrokinase derived from earthworms, Lumbricus rubellus is known to have fibrinolytic enzymes that have potential as therapeutic drugs due to its ability to dissolve fibrin. The current study is aimed to purify the Lumbrokinase from L. rubellus and identify its protein component. METHODS: Water extract of local earthworm Lumbricus rubellus revealed several proteins. Therefore, to identify its protein component, purification through HiPrep DEAE fast flow and proteomic analysis were conducted prior to identifications. A combination of two-dimension gel electrophoresis (2DE) and electrospray ionization mass spectrometry analysis was used to identify the purified fractions. RESULTS: The purified fractions contain five protein bands, namely F25-1, F25-2, F85-1, F85-2, and F85-3, which displayed strong fibrinogenolytic activity. F25 fractions showed fibrinogenolytic activity of 974.85 U/mg, while F85 fractions showed higher activity of 1,484.11 U/mg. Fractions F85-1, F85-2, and F85-3 showed molecular weights of 42.6 kDa, 27.03 kDa, and 14 kDa, respectively and were identified as Lumbrokinase iso-enzymes. CONCLUSION: This preliminary study indicates that the F25 and F85 fractions are similar to published fibrinolytic protease-1 and lumbrokinase, respectively, in terms of their amino acid sequence.

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As reported recently by the present authors, vermicomposting by the epigeic earthworm Eisenia fetida transforms the highly ligninous and allelopathic aquatic weed salvinia (Salvinia molesta) into a benign organic fertilizer. The present study was carried out with four other earthworm species, including three epigeic species of different sizes and phytophagic habits: Eisenia andrei, Lumbricus rubillus, and Perionyx sansibaricus. One anecic species, with geophytophagous habits, was also explored for comparison: Drawida willsi. The objective was to see whether the type of salvinia transformation caused by E. fetida is a general phenomenon or whether there are significant differences in the nature of biocomposts generated by different earthworm species. Accordingly, the characteristics of the biocomposts separately generated by each of the six species mentioned above were assessed with UV-visible spectrophotometry, Fourier-transform infrared spectrometry, differential scanning calorimetry, thermogravimetry, and scanning electron microscopy. The studies reveal that, with minor variations, the biocomposting by all four species was able to remove the intransigence of salvinia and impart plant/soil-friendly attributes to it in substantial measures. All the findings obtained with different techniques corroborated each other in arriving at this conclusion. Hence, it can be said that, in general, biocomposting by earthworms takes away the toxicity of pernicious weeds such as salvinia, converting them into plant-friendly and soil-friendly biofertilizers.

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With vermireactors designed on the basis of the concept of high-rate vermicomposting recently introduced by S.A. Abbasi and co-workers, it has become possible to directly vermicompost phytomass, including pernicious weeds. It has also been shown that upon vermicomposting, even toxic and allelopathic weeds get transformed into highly plant-friendly and soil-friendly organic fertilizers. Pre-existing vemireactors were not able to achieve direct vermicomposting of weeds or other plant biomass, for reasons explained in the main text. But it is necessary to ascertain whether vermireactors can be operated indefinitely with problematic weeds and whether earthworms born in such vermireactors have adequate health and reproductive ability to sustain the vermireactors interminably. Hence the present work has been undertaken to assess the performance of three successive generations of four earthworm species in terms of their ability to vermicompost the highly ligninous aquatic weed salvinia and reproduce in the vermireactors solely fed by it. It was seen that in all cases the first generation of animals, which had been born and grown to adulthood in cow-dung fed vermiculture systems, took time to adapt to the weed-feed, but did so and remained healthy. The next generation which was born and raised in salvinia-fed vermireactor was significantly more efficient in vermicomposting salvinia while the third generation was still more efficient in comparison to the second generation. The trend of third generation being superior to the second and the second being superior to the first was manifest in the production of offspring (juveniles and cocoons) as well. All-in-all the findings, covering 16 months of uninterrupted vermireactor operation, reveal that earthworms tend to get acclimated to have salvinia as their exclusive feed and the successive generations of earthworms that are born and grown in the weed-feed reactors manifest not only greater vermicomposting efficiency but also superior reproductive ability than the earthworms which had been raised on animal manure.

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Earthworms are attracting the attention of bioremediation research because of their short-term impact on pollutant fate. However, earthworm-assisted bioremediation largely depends on the earthworm sensitivity to target pollutants and its metabolic capacity to break down contaminants. The most studied species in soil bioremediation has been Eisenia fetida, which inhabits the soil surface feeding on decomposing organic residues. Therefore, its bioremediation potential may be limited to organic matter-rich topsoil. We compared the detoxification potential against organophosphate (OP) pesticides of three earthworm species representative of the main ecotypes: epigeic, anecic, and endogeic. Selected biomarkers of pesticide detoxification (esterases, cytochrome P450-dependent monooxygenase, and glutathione S-transferase) and oxidative homeostasis (total antioxidant capacity, glutathione levels, and glutathione reductase [GR] and catalase activities) were measured in the muscle wall and gastrointestinal tract of E. fetida (epigeic), Lumbricus terrestris (anecic) and Aporrectodea caliginosa (endogeic). Our results show that L. terrestris was the most suitable species to bioremediate OP-contaminated soil for the following reasons: 1) Gut carboxylesterase (CbE) activity of L. terrestris was higher than that of E. fetida, whereas muscle CbE activity was more sensitivity to OP inhibition than that of E. fetida, which means a high capacity to inactivate the toxic oxon metabolites of OPs. 2) Muscle and gut phosphotriesterase activities were significantly higher in L. terrestris than in the other species. 3) Enzymatic (catalase and GR) and molecular mechanisms of free radical inactivation (glutathione) were 3- to 4-fold higher in L. terrestris concerning E. fetida and A. caliginosa, which reveals a higher potential to keep the cellular oxidative homeostasis against reactive metabolites formed during OP metabolism. Together with biological and ecological traits, these toxicological traits suggest L. terrestris a better candidate for soil bioremediation than epigeic earthworms.

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We present a genome assembly from an individual Lumbricus terrestris (the common earthworm; Annelida; Clitellata; Haplotaxida; Lumbricidae). The genome sequence is 1,056.5 megabases in span. Most of the assembly is scaffolded into 18 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 15.93 kilobases in length.

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We present a genome assembly from an individual Lumbricus rubellus (the red compost earthworm; Annelida; Clitellata; Haplotaxida; Lumbricidae). The genome sequence is 787.5 megabases in span. Most of the assembly is scaffolded into 18 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 15.81 kilobases in length. Gene annotation of this assembly on Ensembl identified 33,426 protein coding genes.

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Agronomic factors can affect mycotoxin contamination of maize, one of the most produced cereals. Maize is usually harvested at 18% moisture, but it is not microbiologically stable until it reaches 14% moisture at the drying plants. We studied how three agronomic factors (crop diversification, tillage system and nitrogen fertilization rate) can affect fungal and mycotoxin contamination (deoxynivalenol and fumonisins B1 and B2) in maize at harvest. In addition, changes in maize during a simulated harvest-till-drying period were studied. DON content at harvest was higher for maize under intensive tillage than using direct drilling (2695 and 474 µg kg-1, respectively). We found two reasons for this: (i) soil crusting in intensive tillage plots caused the formation of pools of water that created high air humidity conditions, favouring the development of DON-producing moulds; (ii) the population of Lumbricus terrestris, an earthworm that would indirectly minimize fungal infection and mycotoxin production on maize kernels, is reduced in intensive tillage plots. Therefore, direct drilling is a better approach than intensive tillage for both preventing DON contamination and preserving soil quality. Concerning the simulated harvest-till-drying period, DON significantly increased between storage days 0 and 5. Water activity dropped on the 4th day, below the threshold for DON production (around 0.91). From our perspective, this study constitutes a step forward towards understanding the relationships between agronomic factors and mycotoxin contamination in maize, and towards improving food safety.

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Accurate prediction of organic contaminant bioavailability for risk assessment in ecological applications is hindered by limited validation on relevant bioassay species. Here, six in-vitro chemical extraction methods (butanol, non-buffered and buffered hydroxypropyl-ß-cyclodextrin (HPCD, Buf-HPCD), Tenax, potassium persulfate oxidation, polyoxymethylene solid phase extraction (POM)) were tested for PAH bioaccumulation prediction in three earthworm ecotypes with dissimilar exposures, Amynthas sp., Eisenia fetida, and Lumbricus terrestris, in historically contaminated soils from manufactured gas plant (MGP) sites. Extractions were compared directly and modelled in a calculation approach using equilibrium partitioning theory (EqPT) with a novel combination of different organic carbon/octanol-water partitioning parameters (KOC and KOW). In the direct comparison approach Buf-HPCD showed the closest prediction of accumulation for burrowing Amynthas sp. and L. terrestris (within 1.5 and 3.1, respectively), but Tenax and POM showed the closest approximation for E. fetida (within 1.1 and 0.9, respectively). The optimum method for predicting PAH bioaccumulation in the calculation approach depended on earthworm species and the partitioning parameters used in equations of the four models, but overall POM, which was independent of KOC, showed the closest approximation of accumulation, within a factor of 2.5 across all species. This work effectively identifies the optimum in-vitro based approaches for PAH bioavailability prediction in earthworms as a model soil health indicator for ecological risk assessment within regulatory and remediation decision frameworks.

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The dreaded weed ipomea (Ipomea carnea), has shown promise as a versatile phytoremediator. But I. carnea plants exude several alkaloids and phenols which are harmful to plants as well as animals. Due to this, the weed imparts as much or more toxicity to the soil as it remediates. These authors have earlier found that upon being vermicomposted by Eisenia fetida ipomea loses its toxicity and becomes a benign organic fertilizer with pest repellant attributes. These findings open up the possibility of using earthworms in those segments of land which are sought to be phytoremediated by ipomea so that the earthworms can keep converting the dead ipomea plants and the debris of live plants to fertilizer. The present work has aimed to determine whether the extent and nature of earthworm impact differs from species to species or is similar across different species. It has revealed that the action of each of the four different earthworm species deployed by the authors caused the C:N ratio of ipomea to change drastically ̶ from 28.20 to 15.95 ± 0.75, bringing the vermicomposts to the category of fertilizers fit for horticulture. The Fourier transform infrared (FTIR) spectra revealed that all the species caused a breakdown of the alkaloids and the phenolic compounds present in ipomea, resulting in the weed's detoxification. The earthworms also effected partial degradation of the lignocellulosic content of ipomea to simpler and more soil-friendly constituents like humic acids. Thermogravimetry, differential scanning calorimetry and scanning electron microscopy corroborated these findings. The influence exerted by the four species of earthworms was similarly beneficial in nature and extent.

First-ever study which establishes the general applicability of earthworms in nullifying the toxic impacts caused by ipomea during its use in phytoremediation, thereby greatly enhancing ipomea's value as a phytoremediator. The studies also provide an avenue for the utilization of the otherwise worthless ipomea harvested after phytoremediation or from natural stands.

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