UNASSIGNED: This study aimed to explore the anti-oxidative and anti-inflammatory properties of Lactococcus lactis subsp. lactis HFY14 (LLSLHFY14) and investigate its effects on the intestinal barrier, cranial nerve, and motor function in mice treated with antibiotics.
UNASSIGNED: Mice were administered an antibiotic mixture (neomycin 5 mg/mL, vancomycin 25 mg/mL, amphotericin B 0.1 mg/mL, ampicillin 10 mg/mL, metronidazole file 5 mg/mL, and lipopolysaccharide 1.5 μg/mL) intraperitoneally, and oxidative stress and inflammatory markers in the serum and brain tissues, and liver index were measured. H&E staining was performed to detect pathological alterations in brain tissues. The expression of intestinal-barrier-related genes and that of genes involved in inflammatory pathways in the brain were detected using polymerase chain reaction (PCR).
UNASSIGNED: LLSLHFY14 administration extended the weight-loaded swimming and running times of mice and decreased the liver index. Moreover, the levels of malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) in the serum and brain tissue were reduced, whereas those of superoxide dismutase (SOD), glutathione (GSH), and interleukin-10 (IL-10) were elevated. Elevated brain expression of the protein kinase B (AKT)/cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF)/extracellular signal-regulated kinase 1 (ERK1) pathway, decreased brain expression of the IL-6 gene, and elevated cecum expression of zonula occludens-1 (ZO-1), occludin-1, and claudin-1 genes were noted. LLSLHFY14 supplementation significantly increased Bacteroidetes expression but decreased Firmicutes expression, thus increasing the Bacteroidetes/Firmicutes ratio.
UNASSIGNED: Overall, LLSLHFY14 supplementation ameliorated antibiotic-induced oxidative stress and inflammation in the mouse central nervous system, intestinal barrier dysfunction, and increased motor function, thus confirming its potential application as probiotics.

Antimicrobial resistance (AMR) stands as an escalating public health crisis fueled by antimicrobial residues in the environment, particularly in soil, which acts as a reservoir for antimicrobial resistance genes (ARGs). Merely quantifying the total extractable concentration of antimicrobials, instead of bioavailable fractions, may substantially underestimate their minimal selection concentration for propagating ARGs. To shed light on the role of bioavailability in ARG abundance within soil, a systematic bioavailability assessment method was established for accurately quantifying the partitioning of multi-class antimicrobials in representative Chinese soils. Microcosm studies unveiled that antimicrobials persisting in the bioavailable fraction could potentially prolong their selection pressure duration to trigger AMR. Notably, the co-occurrence of pesticide or steroid hormone influenced the development trends of ARG subtypes, with fluoroquinolone resistance genes (RGs) being particularly susceptible. Partial least squares path model (PLS-PM) analysis uncovered potentially distinct induction mechanisms of antimicrobials: observable results suggested that extractable residual concentration may exert a direct selection pressure on the development of ARGs, while bioavailable concentration could potentially play a stepwise role in affecting the abundance of mobile genetic elements and initiating ARG dissemination. Such unprecedented scrutinization of the interplay between bioavailable antimicrobials in soils and ARG abundance provides valuable insights into strategizing regulatory policy or guidelines for soil remediation.

Antibiotics are widely used to treat bacterial infection and reduce the mortality rate, while antibiotic overuse can cause gut microbiota dysbiosis. The impact of antibiotics on gut microbiota is not fully understood. In our study, four commonly used antibiotics (ceftazidime, cefoperazone-sulbactam, imipenem-cilastatin, and moxifloxacin) were given subcutaneously to mice, and their impacts on the gut microbiota composition and serum cytokine levels were evaluated through 16S rRNA analysis and a multiplex immunoassay. Antibiotic treatment markedly reduced gut microbiota diversity and changed gut microbiota composition. Antibiotic treatment significantly increased and decreased the abundance of Firmicutes and Bacteroidota, respectively. The antibiotic treatments increased the abundance of opportunistic pathogens such as Enterococcus and decreased that of Lachnospiraceae and Muribaculaceae. For moxifloxacin, the significantly high abundance of Enterococcus and Klebsiella was observed after 14 and 21 days of treatment. However, a relatively low abundance of opportunistic pathogens was found after 14 days of imipenem-cilastatin treatment. Additionally, the serum levels of various pro-inflammatory cytokines, such as IL-1β, IL-12 (p70), and IL-17, significantly increased after 21 days of antibiotic treatments. Overall, these results provide a guide for rational use of antibiotics in clinical settings: short-term use of moxifloxacin is recommended with regard to gut microbiota health, and the 14-day use of imipenem-cilastatin may have a less severe impact than other antibiotics.IMPORTANCEAntibiotic treatments are directly associated with changes in gut microbiota and are effective against both pathogens and beneficial bacteria. Gut microbiota dysbiosis induced by antibiotic treatment could increase the risk of some diseases. Therefore, an adequate understanding of gut microbiota changes after antibiotic use is crucial. In this study, we investigated the effects of continuous treatment with antibiotics on gut microbiota, serum cytokines, and intestinal inflammatory response. Our results suggest that short-term use of moxifloxacin is recommended, and the 14-day use of imipenem-cilastatin may have a less severe effect on gut microbiota health than cefoperazone-sulbactam. These results provide useful guidance on the rational use of antibiotics with regard to gut microbiota health.

The gut microbiota plays a crucial role in postnatal growth, particularly in modulating the development of animals during their growth phase. In this study, we investigated the effects of antibiotic-induced dysbiosis of the gut microbiota on the growth of weaning rats by administering a non-absorbable antibiotic cocktail (ABX) in water for 4 weeks. ABX treatment significantly reduced body weight and feed intake in rats. Concurrently, ABX treatment decreased microbial abundance and diversity in rat ceca, predominantly suppressing microbes associated with bile salt hydrolase (BSH) activity. Furthermore, decreased appetite may be attributed to elevated levels of glucagon-like peptide-1 (GLP-1) in the serum, along with reduced neuropeptide Y (NPY) and increased cocaine and amphetamine-regulated transcript (CART) in the hypothalamus at the mRNA level. Importantly, concentrations of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor 2 (IGF-2) were decreased in the serum and liver of antibiotic-treated rats. These alterations were associated with significant down-regulation of IGF-2 mRNA in the liver and significantly decreased farnesoid X receptor (FXR) protein expression and binding to the IGF-2 promoter. These results indicate that antibiotic-induced gut microbial dysbiosis not only impacts bile acid metabolism but also diminishes rat growth through the FXR-mediated IGF-2 pathway.

Mariculture stands as a pivotal enterprise aimed at enhancing the quality of human existence. However, the utilization of antibiotics and pesticides in the mariculture process poses threats to both the environment and human well-being. Therefore, it is of great significance to investigate the occurrence, distribution and risk of antibiotics and pesticides in mariculture areas. In this study, 11 kinds of antibiotics and 12 kinds of pesticides were screened in four mariculture areas around Liaodong Peninsula in China. The pollution characteristics of pollutants were investigated in three different mariculture stages. The pollution in the reproduction stage was the most serious, indicating that mariculture may have a potential impact on the surrounding seawater. Health risk assessment results indicate that the pollutants have a significant risk to human health, therefore it is necessary to strengthen the control of chemicals used in mariculture in future.

Antibiotics are widely utilized in agriculture for the prevention and treatment of animal diseases. How-ever, the abuse and overuse of antibiotics progressively increase the risks of antibiotic residues and antibiotic resis-tance. The bioaccumulation and biomagnification of antibiotics through food chains will negatively affect ecological safety, and finally threaten human health. There are many shortages of traditional antibiotic detection techniques, such as complex procedures, complicated operation and time consuming, and thus are difficult to meet the demand of instant, efficient and accurate on-site detection. Therefore, it is crucial to develop rapid detection techniques of antibiotics to manage the application of antibiotics in agriculture. We reviewed the utilization, and management of antibiotics in animal husbandry, residual characteristics, and potential hazards of antibiotics in agricultural products, summarized the advancements in rapid detection techniques of antibiotics in agricultural products over the past five years, compared the advantages and disadvantages of different rapid detection techniques, and prospected the future development in this area. This review would provide a valuable reference to the control and point-of-care test of antibiotics in agricultural products.
在农业上,抗生素广泛用于动物的疾病预防和治疗。但抗生素的过度使用,甚至滥用,使得抗生素残留和抗生素耐药性问题日渐严重。抗生素通过食物链的生物富集和放大,将影响生态环境安全,并最终危害人体健康。传统的抗生素检测技术存在程序繁琐、操作复杂、耗时长等一系列问题,难以满足即时、高效和准确的现场检测需求。因此,为应对抗生素引起的食品安全问题、规范抗生素在农业上的使用,建立农产品抗生素的快速检测技术显得十分重要。本文综述了世界主要国家地区抗生素在养殖业的使用和管理情况,以及抗生素在农产品中的残留特征和对生物体及环境的危害,归纳了近5年内农产品中抗生素快速检测技术的发展情况,对各项快速检测技术的优缺点进行了对比,最后对未来发展方向进行了展望。本文可为农产品抗生素管控和即时检测提供借鉴。.

In this review, we have summarized the current knowledge about the environmental importance, relevance, and consequences of microbial arsenic (As) methylation in various ecosystems. In this regard, we have presented As biomethylation in terrestrial and aquatic ecosystems particularly in rice paddy soils and wetlands. The functions of As biomethylation by microbial consortia in anaerobic and aerobic conditions are extensively discussed. In addition, we have tried to explain the interconnections between As transformation and carbon (C), such as microbial degradation of organic compounds and methane (CH4) emission. These processes can cause As release because of the reduction of arsenate (As(V)) to the more mobile arsenite (As(III)) as well as As methylation and the formation of toxic trivalent methylated As species in anaerobic conditions. Furthermore, the sulfur (S) transformation can form highly toxic thiolated As species owing to its interference with As biomethylation. Besides, we have focused on many other mutual interlinks that remain elusive between As and C, including As biomethylation, thiolation, and CH4 emission, in the soil-water systems. Recent developments have clarified the significant and complex interactions between the coupled microbial process in anoxic and submerged soils. These processes, performed by little-known/unknown microbial taxa or well-known members of microbial communities with unrecognized metabolic pathways, conducted several concurrent reactions that contributed to global warming on our planet and have unfavorable impacts on water quality and human food resources. Finally, some environmental implications in rice production and arsenic removal from soil-water systems are discussed. Generally, our understanding of the ecological and metabolic evidence for the coupling and synchronous processes of As, C, and S are involved in environmental contamination-caused toxicity in human food, including high As content in rice grain, water resources, and global warming through methanogenesis elucidate combating global rice safety, drinking water, and climate changes.

Contamination of aquatic products with sulfonamide antibiotics poses a threat to consumer health and can lead to the emergence of drug-resistant bacteria. Common methods to detect such compounds are slow and require expensive instruments. We developed a sensitive sulfadiazine (SDZ) detection method based on the photoinduced electron transfer between UCNPs and Cu2+. The surface-modified upconversion nanoparticles bind to Cu2+ by electrostatic adsorption, causing fluorescence quenching. The quenched fluorescence was subsequently recovered by the addition of imidazole and SDZ to the detection system, which formed a complex with Cu2+. The sensor showed excellent linearity over a wide concentration range (0.05-1000 ng/mL), had a low limit of detection (0.04 ng/mL), was selective, and was not affected by common substances present in aquatic media. This indicates that the sensor has great potential for application in the detection of SDZ residues in aquatic products.

Microplastics and antibiotics coexist in aquatic environments, especially in freshwater aquaculture areas. However, as the second largest production of polyvinyl chloride (PVC) in the world, the effects of co-exposure to microplastics particles and antibiotics on changes in antibiotic resistance gene (ARG) profiles and the microbial community structure of aquatic organism gut microorganisms are poorly understood. Therefore, in this study, carp (Cyprinus carpio) were exposed to single or combined PVC microplastic contamination and oxytetracycline (OTC) or sulfamethazine (SMZ) for 8 weeks. PVC microplastics can enrich potential pathogenic bacteria, such as Enterobacter and Acinetobacter, among intestinal microorganisms. The presence of PVC microplastics enhanced the selective enrichment and dissemination risk of ARGs. PVC microplastics combined with OTC (OPVC) treatment significantly increased the abundance of tetracycline resistance genes (1.40-fold) compared with that in the OTC exposure treatment, revealing an obvious co-selection effect. However, compared with those in the control group, the total abundance of ARGs and MGEs in the OPVC treatment groups were significantly lower, which was correlated with the reduced abundances of the potential host Enterobacter. Overall, our results emphasized the diffusion and spread of ARGs are more influenced by PVC microplastics than by antibiotics, which may lead to antibiotic resistance in aquaculture.

Nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) is an important methane (CH4) consumption and nitrogen (N) removal pathway in estuarine and coastal wetlands. Antibiotic contamination is known to affect microbially mediated processes; however, its influences on n-DAMO and the underlying molecular mechanisms remain poorly understood. In the present study, using 13CH4 tracer method combined with molecular techniques, we investigated the responses of n-DAMO microbial abundance, activity, and the associated microbial community composition to sulfamethazine (SMT, a sulfonamide antibiotic, with exposure concentrations of 0.05, 0.5, 5, 20, 50, and 100 µg L-1). Results showed that the effect of SMT exposure on n-DAMO activity was dose-dependent. Exposure to SMT at concentrations of up to 5 µg L-1 inhibited the potential n-DAMO rates (the average rates of nitrite- and nitrate-DAMO decreased by 92.9 % and 79.2 % relative to the control, respectively). In contrast, n-DAMO rates tended to be promoted by SMT when its concentration increased to 20-100 µg L-1 (the average rates of nitrite- and nitrate-DAMO increased by 724.1 % and 630.1 % relative to the low-doses, respectively). Notably, low-doses of SMT suppressed nitrite-DAMO to a greater extent than nitrate-DAMO, indicating that nitrite-DAMO was more sensitive to SMT than nitrate-DAMO. Molecular analyses suggest that the increased n-DAMO activity under high-doses SMT exposure may be driven by changes in microbial communities, especially because of the promotion of methanogens that provide more CH4 to n-DAMO microbes. Moreover, the abundances of n-DAMO microbes at high SMT exposure (20 and 50 µg L-1) were significantly higher than that at low SMT exposure (0.05-5 µg L-1). These results advance our understanding of the ecological effects of SMT on carbon (C) and N interactions in estuarine and coastal wetlands.