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Based on the fact that not all chemical substances possess good Raman signals, this article focuses on the Raman silent region signals of pesticides with cyano group. Under the optimized conditions of methanol-water (1:1, v/v) as the solvent, irradiation at 302 nm light source for 20 min, and the use of 0.5 mol/L KI as the aggregating agent, Surface-enhanced Raman spectroscopy (SERS) method for azoxystrobin detection was developed by the Raman silent region signal of 2230 cm -1 , and verified by detecting the spiked grapes with different concentrations of azoxystrobin. Other four pesticides with cyano group also could be identified at the peak of 2180 cm -1 , 2205 cm -1 , 2125 cm -1 , and 2130 cm -1 for acetamiprid, phoxim, thiacloprid and cymoxanil, respectively. When azoxystrobin or acetamiprid was mixed respectively with chlorpyrifos without cyano group, their SERS signals in the Raman silent region of chlorpyrifos were not interfered, while mixed with cymoxanil in different ratios (1:4, 1:1 and 4:1), respectively, each two pesticides with cyano group could be distinguished by the changes in the Raman silent region. In further, four pesticides with or without cyano group were mixed together in 1:1:1:1 (acetamiprid, cymoxanil, azoxystrobin chlorpyrifos), and each pesticide still could be identified even at 0.5 mg/L. The results showed that the SERS method combined with UV irradiation may provide a new way to monitor the pesticides with C≡N performance in the Raman silent region without interference from the food matrix., 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.)

Carbofuran and acetamiprid pose the highest residual risk among pesticides found in wolfberries. This study aimed to degrade these pesticides in wolfberries using a multi-array dielectric barrier discharge plasma (DBD), evaluate the impact on safety and quality and explore their degradation mechanism. The results showed that DBD treatment achieved 90.6% and 80.9% degradation rates for carbofuran and acetamiprid, respectively, following a first-order kinetic reaction. The 120 s treatment successfully reduced pesticide contamination to levels below maximum residue limits. Treatment up to 180 s did not adversely affect the quality of wolfberries. QTOF/MS identification and degradation pathway analysis revealed that DBD broke down the furan ring and carbamate group of carbofuran, while replacing the chlorine atom and oxidizing the side chain of acetamiprid, leading to degradation. The toxicological evaluation showed that the degradation products were less toxic than undegraded pesticides. Molecular dynamics simulations revealed the reactive oxygen species (ROS) facilitated the degradation of pesticides through dehydrogenation and radical addition reactions. ROS type and dosage significantly affected the breakage of chemical bonds associated with toxicity (C 4 -O 5 and C 2 -Cl 1 ). These findings deepen insights into the plasma chemical degradation of pesticides., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

[Display omitted] • M. micrantha derived-biochar for the control and reuse of invasive resources. • Biochar modified microspheres achieve the rapid and complete removal of CHT in field. • Microspheres accelerate CHT contact with bacteria and promote biofilm formation. • Degradation pathway and products indicate that CHT is thoroughly mineralized. Managing invasive plant presents a significant challenge to both the environment and the economy. There is an opportunity to address this issue by utilizing invasive plants as a sustainable and cost-effective source of valuable functional materials for environmental remediation. In this study, a promising Mikania micrantha biochar (MB) was synthesized by pyrolyzing an invasive plant, which was utilized for bacterial immobilization and adsorption of contaminants. By embedding Proteus terrae ZQ02-MB within a polyvinyl alcohol-sodium alginate gel to create a biochar-modified bacterial microsphere (BBM), the superior degradation of pesticide contaminants was observed. Taking chlorothalonil (CHT) as an example, field experiments demonstrated that BBM achieved a removal efficiency of 59.8% by the third day. Additionally, BBM not only improved the richness and diversity of soil bacteria but also enhanced the microbial community structure by the seventh day. On this basis, the adsorption capacity of MB, biofilm growth promoting ability of BBM, and the CHT mineralization ability of strain ZQ02 were validated as a joint mechanism to promote efficient CHT removal. Overall, this study proposes a composite model of invasive plant-derived biochar loaded microorganisms, which has great potential in eliminating pollutant residues and paves new paths to develop strategies for reusing invasive species resources. [ABSTRACT FROM AUTHOR]