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Foodborne health risks posed by antibiotic resistant genes (ARGs) and pathogenic bacteria have garnered increasing global attention. However, the patterns of their propagation and reduction, as well as the resulting health risks in the human gastrointestinal tract, remain unknown. We employed leafy vegetables (water spinach), solanaceous vegetables (pepper), and root vegetables (radish) to investigate the propagation and reduction patterns of ARGs and pathogenic bacteria within an in vitro simulated digestion system. This system mimicked the soil-vegetable-stomach-small intestine (SVSTI) transmission chain. We found that kan, oqxA, and multidrug resistance genes were enriched by 1.10-fold, 11.2-fold, and 2.21-fold, respectively, along the transmission chain. The succession of bacterial communities and horizontal gene transfer mediated by intl1 were identified as the primary drivers of ARG accumulation. Notably, certain pathogenic bacteria (Bacillus cereus, Klebsiella pneumoniae) accumulated in the intestinal environment. According to our proposed health risk assessment system, Bacillus species, as potential ARG hosts, and multidrug ARGs are at a higher risk of exposure to intestinal environment through the transmission chain. Our findings highlight the significant health risks associated with the intake of ARGs and pathogenic bacteria carried by vegetables, emphasizing an urgent need to implement effective biological control measures in vegetable production and consumption., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Massive use of plastic products has caused their accumulation in soils, releasing large amounts of endogenous plastic additives (e.g., benzotriazole ultraviolet stabilizers, in short BZT-UVs) into terrestrial ecosystems. However, their plant toxicity is little known. Herein, we investigated the occurrence of BZT-UVs in contaminated farmland and selected three BZT-UV congeners to explore their toxic effects on the antioxidant, photosynthetic, and metabolic perturbation on rice (Oryza sativa). Results showed that the mean concentrations of ∑BZT-UVs in soil and plant samples were 180.7 ng/g dw and 156.4 ng/g dw, respectively. UV-P, UV-327 and UV-328 were the dominant BZT-UV congeners in both of soils and plants. Three BZT-UV congeners caused oxidative damages to rice in a dose-dependent manner, especially for UV-328. Functional genes involved in chlorophyll synthetases was inhibited by over 50 % under the stress of BZT-UVs, whereas those responsible for chlorophyll degradation were obviously promoted. The chlorophyll content was thus decreased, leading to a weakened photosynthesis system and an unbalanced carbon metabolism. The transcriptome and metabolome proved that the flux of carbohydrate metabolism and amino acid metabolism were obviously promoted in plants induced by BZT-UVs, which could inhibit the growth of rice. These findings offered insights into the coordinated responses of plants and advanced our understanding of potential ecological risks of BZT-UVs to terrestrial ecosystems., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pathogenic microorganisms with antibiotic resistance genes (ARGs) pose a serious threat to public health and soil ecology. Although new drugs and available antibacterial materials can kill ARG carriers but accidentally kill beneficial microorganisms. Therefore, the rapid enrichment and separation of ARGs and their carriers from soil is becoming an important strategy for controlling the diffusion of ARGs. Hydroxamate siderophore (HDS) has gained widespread attentions for its involvement in trace element transfer among microorganisms in the soil environment, we thus explored an in-situ trapping-enrichment method for ARGs and their carriers via a small molecular HDS secreted by Pseudomonas fluorescens HMP01. In this study, we demonstrate that HDS significantly in-situ traps and enriches certain ARGs, including chloramphenicol, MLS, rifamycin, and tetracycline resistance genes in the soil environment. The enrichment efficiencies were 1473-fold, 38-fold, 17-fold, and 5-fold, respectively, higher than those in the control group. Specifically, the primary enriched ARGs were rpoB, mphL, catB2, and tetA(60), and Bacillus, Rhizobium, Rossellomorea, and Agrobacterium were hosts for these ARGs. This enrichment was caused by the upregulation of chemotaxis genes (e.g., cheW, cheC, and cheD) and rapid biofilm formation within the enriched bacterial population. Notably, representative ARGs such as cat, macB, and rpoB were significantly reduced by 36%, 85.7%, and 72%, respectively, in the paddy soil after HDS enrichment. Our research sheds light on the potential application of siderophore as a rapping agent for the eco-friendly reduction of ARGs and their carriers in soil environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Biochar (BC) was used to remove trichloroethylene (TCE) from soil and water phases, and BC modification changed the sorption behavior of pollutants. Microplastics are emerging pollutants in the soil and water phases. Whether microplastics can affect the sorption of TCE by modified BC is not clear. Thus, batch sorption kinetics and isotherm experiments were conducted to elucidate the sorption of TCE on BC, and BC combined with polyethylene (PE) or polystyrene (PS). The results showed that HCl and NaOH modification increased TCE sorption on BC, while HNO 3 modification inhibited TCE sorption on BC. When PE/PS and BC coexisted, the TCE sorption capacity decreased significantly on BC-CK + PE, BC-HCl + PE, BC-HNO 3 + PE, BC-NaOH + PE, and BC-NaOH + PS, which was likely due to the preferential sorption of PE/PS on BC samples. We concluded that microplastics can change TCE sorption behavior and inhibit TCE sorption on BC samples. Thus, the interaction of BC and microplastics should be considered when BC is used for TCE removal in soil and water remediation., Competing Interests: The authors declare there is no conflict., (© 2024 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).)

This study investigated the transformations of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in rhizosphere soils and adaptive responses of rhizobacterial community under the real field conditions during four growth stages (e.g., greening, tillering, heading, and maturity) of early rice (Zhongjiazao 17) and late rice (Zhongyou 9918) in Jiangshe village (JSV) and Yangji village (YJV). Results showed that rhizosphere soils of YJV were mildly polluted by Cd and PAHs compared to that of JSV. The relative abundance of bioavailable Cd (bio-Cd) and bioavailable As (bio-As) in rhizosphere soil increased before the heading stage but decreased at the subsequent growth stage, but the content of ΣPAHs in rhizosphere soil decreased gradually during whole growth period. The dominant rhizobacteria genera at YJV (e.g., Bacillus, Massilia, Sphingomonas, and Geobacter) increased at an abundance level from the tillering to heading stage. Rhizobacteria interacted with the above co-pollutant more intensely at the tillering and heading stage, where genes involved in HM-resistance and PAH-degradation appeared to have a significant enhancement. The contents of bio-Cd and bio-As in rhizosphere soil of early rice were higher than that of late rice at each growth stage, especially at the heading stage. Bio-Cd, ΣPAHs, and organic matter were key factors influencing the community structure of rhizobacteria. Results of this study provide valuable insights about the interactions between HM-PAH co-pollutant and rhizobacterial community under real field conditions and thus develop in-situ rhizosphere remediation techniques for contaminated paddy fields., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

This study investigated the diffusion and enrichment of antibiotic resistance genes (ARGs) and pathogens via the transmission chain (mulberry leaves - silkworm guts - silkworm feces - soil) near a manganese mine restoration area (RA) and control area (CA, away from RA). Horizontal gene transfer (HGT) of ARGs was testified by an IncP a-type broad host range plasmid RP4 harboring ARGs (tetA) and conjugative genes (e.g., korB, trbA, and trbB) as an indicator. Compared to leaves, the abundances of ARGs and pathogens in feces after silkworms ingested leaves from RA increased by 10.8% and 52.3%, respectively, whereas their abundance in feces from CA dropped by 17.1% and 97.7%, respectively. The predominant ARG types in feces involved the resistances to β-lactam, quinolone, multidrug, peptide, and rifamycin. Therein, several high-risk ARGs (e.g., qnrB, oqxA, and rpoB) carried by pathogens were more enriched in feces. However, HGT mediated by plasmid RP4 in this transmission chain was not a main factor to promote the enrichment of ARGs due to the harsh survival environment of silkworm guts for the plasmid RP4 host E. coli. Notably, Zn, Mn, and As in feces and guts promoted the enrichment of qnrB and oqxA. Worriedly, the abundance of qnrB and oqxA in soil increased by over 4-fold after feces from RA were added into soil for 30 days regardless of feces with or without E. coli RP4. Overall, ARGs and pathogens could diffuse and enrich in environment via the sericulture transmission chain developed at RA, especially some high-risk ARGs carried by pathogens. Thus, greater attentions should be paid to dispel such high-risk ARGs to support benign development of sericulture industry in the safe utilization of some RAs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Nitrobenzene is a widespread contaminant in water. Biochar (BC) is a promising material for removing organic pollutants, but the adsorption capacity of pristine BC is low. Chemical modification is often used to improve the adsorption performance, but information on the sorption of nitrobenzene by modified BC is rare. In this study, BCs pyrolyzed at 300, 500, and 700 °C were modified by hydrochloric acid (HCl), sulfuric acid (H 2 SO 4 ), sodium hydroxide (NaOH), hydrogen peroxide (H 2 O 2 ), and nitric acid (HNO 3 ), respectively. The properties, nitrobenzene sorption behaviors, and sorption mechanisms of different BCs were analyzed. The results showed that chemical modification decreased the sorption of nitrobenzene on BCs pyrolyzed at 300 °C, possibly due to the loss of the partition phase and the increase in polarity after modification. Regarding BCs pyrolyzed at 500 and 700 °C, the NaOH and HCl modifications significantly increased the sorption capacity by 19% and 60%, 18%, and 41%, respectively, possibly due to the increase in surface area, available pores, and aromaticity, while HNO 3 modification decreased the sorption capacity by 41% and 31%. Two reasons were probably responsible for the decrease: one was the decrease in surface area after HNO 3 modification due to the destruction of pore walls and the continuity of holes; the other was the strong repulsion between the nitro groups formed on the surface of BC and the nitro groups of nitrobenzene that drove nitrobenzene molecules away from the surface. A principal component-based comprehensive evaluation of the BC properties, which were significantly correlated with the sorption isotherm parameters, was used to evaluate the nitrobenzene sorption performance of the modified BC. Overall, BC pyrolyzed at 700 °C modified with NaOH or HCl were proposed as effective sorption materials for the removal of nitrobenzene in environment, which also provided a chemical modified method of biochar derived from agricultural waste., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To improve the accuracy of signal recognition in optical fiber perimeter defense systems, a method based on Mel frequency cepstral coefficients (MFCCs) and a fast dynamic time warping (FastDTW) algorithm is proposed. Four kinds of sensing signals are acquired by employing an in-line Sagnac interferometer system. MFCC features of the signals are extracted. The FastDTW algorithm is utilized to calculate distances of the optimal warping paths between a test sample and all reference templates. According to the nearest neighbor criterion, signal recognition results are obtained. The average accuracy is over 96%. This proposed identification method is highly efficient and easy to implement.

Dissolved organic matter (DOM) is an important organic matter fraction that affects many biological and chemical processes in soil. Biochar can change soil DOM while the effects were paradoxical, and contributions of biochar to soil DOM was not clear yet. In this study, excitation-emission matrix (EEM) fluorescence spectroscopy was applied to determine the biochar-induced changes of DOM composition. Batch experiments were conducted to quantify the contributions of biochar to soil DOM. Biochars were prepared by pyrolyzing wheat straw (S300/700) and cow manure (M300/700) at 300 and 700 °C, respectively. Generally, biochar increased the humification of soil DOM possibly by the release of indigenous DOM and selective adsorption of the small molecule DOM. Besides, contributions of S300 and M300 to soil DOM (37-91%) were higher than that of S700 and M700 (2-19%) irrespective of application rates. The indigenous DOM released from S300 and M300 was 6.4-12.1 times more than the soil DOM adsorbed by S300 and M300, leading to the increase of DOM content. Contrarily, the DOM from S700 and M700 was only 11-17% of the soil DOM adsorbed by them, resulting in the decrease of DOM content. In addition, contributions of biochar to soil DOM increased as the application rate increased, especially for S300 and M300. This study indicated that the release and adsorption of DOM were the key processes determining the effects of biochar on soil DOM, which were closely related to the pyrolysis temperature and application rate of biochar., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The present study was conducted to explore the mechanisms of surfactant-enhanced phytoremediation of soils contaminated with polycyclic aromatic hydrocarbons (PAHs), focusing on the bioavailability of PAHs and microbial diversity. We investigated the remediation efficiencies of phenanthrene and pyrene after the addition of mixed surfactants (sodium dodecyl benzene sulfonate (SDBS) and Tween 80) of different ratios (1:1, 1:2, and 2:1) at the concentration of 100 mg/kg to soils cultured with ryegrass (Lolium multiflorum L.). The fractions of phenanthrene and pyrene were determined using a sequential extraction method, and the microbial diversity was evaluated using 16S rRNA gene high-throughput sequencing. The results showed that mixed surfactants could enhance the remediation efficiencies of PAHs, and mainly occurred in the initial 21 days. Mixed surfactants at the ratio of 1:1 (HM1) showed the best remediation efficiency in enhancing the dissipation of pyrene in 21 days. Mixed surfactants showed little effects on the removal of phenanthrene. In general, HM1 significantly decreased the bioavailable, bound and residual fractions of pyrene; additionally, higher abundances of PAH-degradation bacteria and degradation-related genes were observed. Pearson correlation analysis among PAH degraders, degradation-related genes and bioavailable fraction of PAHs was performed. Our results indicated that mixed surfactants could promote the transformation of pyrene from the bound and residual fractions to bioavailable fractions and enhance the abundances of PAH degradation bacteria and PAH degradation-related genes, thereby enhancing the degradation of pyrene., (Copyright © 2018. Published by Elsevier B.V.)

Root exudates play an important role in the phytoremediation of soils contaminated by organic pollutants, but how root exudate components affect the remediation process is not well understood. In this study, we explored the effects and mechanisms of the major root exudates, including glucose, organic acids, and serine, in the rhizoremediation of pyrene-contaminated soil. The results showed that glucose increased the degradation of pyrene (54.3 ± 1.7%) most significantly compared to the organic acids (45.5 ± 2.5%) and serine (43.2 ± 0.1%). Glucose could significantly facilitate the removal of pyrene in soil through promoting dehydrogenase activity indicated by a positive correlation between the removal efficiency of pyrene and the soil dehydrogenase activity (p < 0.01). Furthermore, root exudates were able to change soil microbial community, particularly the bacterial taxonomic composition, thereby affecting the biodegradation of pyrene. Glucose could alter soil microbial community and enhance the amount of Mycobacterium markedly, which is dominant in the degradation of pyrene. These findings provide insights into the mechanisms by which root exudates enhance the degradation of organic contaminants and advance our understanding of the micro-processes involved in rhizoremediation.

To reveal the pollution status associated with rapid urbanization and economic growth, extensive areas of agricultural soils (approximately 45,800 km(2)) in the Yangtze River Delta of China were investigated with respect to selected endocrine disruptor compounds (EDCs), including phthalate esters (PAEs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). The residues of sum of 15 PAEs, sum of 15 OCPs and sum of 13 PBDEs were in the range of 167-9370 ng/g, 1.0-3520 ng/g, and <1.0-382 ng/g, respectively. The OCPs residuals originated from both historical usage and recent input. Agricultural plastic film was considered to be an important source of PAEs. Discharge from furniture industry was potential major source of PBDEs in this region. The selected pollutants showed quite different spatial distributions within the studied region. It is worth noting that much higher concentrations of the EDCs were found on the borders between Shanghai and the two neighboring provinces, where agriculture and industry developed rapidly in recent years. Contaminants from both agricultural and industrial activities made this area a pollution hotspot, which should arouse more stringent regulation to safeguard the environment and food security., (Copyright © 2015 Elsevier B.V. All rights reserved.)