Our study is the first to demonstrate the existence of high levels of mobile genes conferring reduced susceptibility to fluoroquinolones as well as the presence of ESBL genes in fish produced in China, and identifies a significant reservoir of antibiotic resistance genes relevant to human medicine.

Salmonella spp. is one of the most important food-borne pathogens causing digestive tract and invasive infections in both humans and animals. Extended-spectrum β-lactamases (ESBLs) especially the CTX-M-type ESBLs are increasingly being reported worldwide and in China. These studies seldom focused on Salmonella isolates from food-producing animals. The aim of this study was to characterize the antimicrobial resistance profiles, serotypes and ESBLs and in particular, CTX-M producing Salmonella isolates from chickens and pigs in China. Salmonella isolates were identified by API20E system and polymerase chain reaction (PCR) assay; serotypes were determined using slide agglutination with hyperimmune sera; antimicrobial susceptibility was tested using the ager dilution method; the prevalence of ESBLs and PMQR genes were screened by PCR; CTX-M-producing isolates were further characterized by conjugation along with genetic relatedness and plasmid replicon type. In total, 159 Salmonella strains were identified, among which 95 strains were Salmonella enterica serovar Typhimurium, 63 strains were S. enterica serovar Indiana, and 1 strain was S. enterica serovar Enteritidis. All of these isolates presented multi-drug resistant phenotypes. Forty-five isolates carried blaCTX-M genes, the most common subtype was CTX-M-27(34), followed by CTX-M-65(7) and CTX-M-14(4). Most blaCTX-M genes were transmitted by non-typeable or IncN/IncFIB/IncP/IncA/C/IncHI2 plasmids with sizes ranging from 80 to 280 kb. In particular, all the 14 non-typeable plasmids were carrying blaCTX-M-27 gene and had a similar size. PFGE profiles indicated that CTX-M-positive isolates were clonally related among the same serotype, whilst the isolates of different serotypes were genetically divergent. This suggested that both clonal spread of resistant strains and horizontal transmission of the resistance plasmids contributed to the dissemination of blaCTX-M-9G-positive Salmonella isolates. The presence and spread of CTX-M, especially the CTX-M-27 in S. enterica serovars Typhimurium and Indiana from food-producing animals poses a potential threat for public health. Control strategies to limit the dissemination of these strains through the food chain are necessary.

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Agrochemicals have supported the development of the agricultural economy and national population over the past century. However, excessive applications of agrochemicals pose threats to the environment and human health. In the last decades, nanoparticles (NPs) have been a hot topic in many fields, especially in agriculture, because of their physicochemical properties. Nevertheless, the prevalent methods for fabricating NPs are uneconomical and involve toxic reagents, hindering their extensive applications in the agricultural sector. In contrast, inspired by biological exemplifications from microbes and plants, their extract and biomass can act as a reducing and capping agent to form NPs without any toxic reagents. NPs synthesized through these bioinspired routes are cost-effective, ecofriendly, and high performing. With the development of nanotechnology, biosynthetic NPs (bioNPs) have been proven to be a substitute strategy for agrochemicals and traditional NPs in heavy-metal remediation of soil, promotion of plant growth, and management of plant disease with less toxicity and higher performance. Therefore, bioinspired synthesis of NPs will be an inevitable trend for sustainable development in agricultural fields. This critical review will demonstrate the bioinspired synthesis of NPs and discuss the influence of bioNPs on agricultural soil, crop growth, and crop diseases compared to chemical NPs or agrochemicals.

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Excessive solar radiation and high temperature often cause considerable loss and waste of fruits during transportation, retail, and storage. In the current study, a natural deep eutectic solvent-based polyacrylamide/poly(vinyl alcohol) hydrogel with nanoparticles (NPs/ NADES@PAAm/PVA) is developed for fruit quality protection from solar radiation and high-temperature stress by achieving the combined effect of radiative and evaporative cooling. NPs/NADES@PAAm/PVA presents an average solar reflectance of ∼0.89 and an average emittance at the atmospheric window of ∼0.90. Besides, NPs/NADES@PAAm/PVA possesses excellent flexibility, robust mechanical strength, and good swelling behavior. The fruit preservation experiments under sunlight demonstrate that the pear (Pyrus sinkiangensis) treated with NPs/NADES@PAAm/PVA can achieve an average temperature decrease of ∼15.3 °C after sun exposure compared with the blank, and its quality-related attributes, including color, total soluble solid, relative conductivity, and respiration rate, are similar to the fresh one. Multivariate data analyses, including principal component analysis and cluster analysis, further verify that the pear treated with NPs/NADES@PAAm/PVA possesses similar quality to the fresh one after sun exposure. Thus, NPs/ NADES@PAAm/PVA has promising prospects for fruit transportation, retail, and storage under solar radiation in a low-operationcost and sustainable manner.

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