Although abundant evidence has suggested that early-life antibiotic exposure was associated with adipogenesis later in life, limited data were available on the effect of intrauterine antibiotic exposure on infant growth and growth speed. Additionally, few studies have investigated the role of the neonatal gut microbiota in the above association. In this study, we examined the association between intrauterine cumulative antibiotic exposure and infant growth and explored the potential role of the neonatal gut microbiota in the association. 295 mother-child pairs from the Shanghai Maternal-Child Pairs Cohort (MCPC) study were included, and meconium samples and infant growth measurements were assessed. Z-scores of length-for-age, weight-for-age (weight-for-age), and body mass index (BMI)-for-age (BMI-for-age) were calculated. Eighteen common antibiotics were measured in meconium. Multivariable linear regression models were applied to test the interrelationships between antibiotic exposure, diversity indicators, and the relative abundance of selected bacterial taxa from phylum to genus levels from least absolute shrinkage and selection operator (LASSO) and infant growth indicators. The detection rates of the 18 antibiotics, except for chlortetracycline, penicillin, and chloramphenicol, were below 10 %. Penicillin was found to be positively associated with infant growth at birth and with growth speed from 2 to 6 months. The Pielou and Simpson indexes were negatively associated with meconium penicillin. Nominally significant associations between penicillin and the relative abundances of several bacterial taxa from the phyla Proteobacteria, Bacteroidetes, and Firmicutes were found. The Pielou and Simpson indexes were also found to be negatively associated with infant growth. Among taxa selected from LASSO regression, the relative abundances of the phyla Actinobacteria and Firmicutes and order Bifidobacteriales were found to be significantly associated with weight and BMI growth speeds from 2 to 6 months. In conclusion, intrauterine antibiotic exposure can affect infant growth. The neonatal gut microbiota might play a role in the abovementioned association.

Penicillin fermentation dreg (PFD) is a solid waste discharged by pharmaceutical enterprises in the fermentation production process. Due to the residual antibiotic of PFD, the risk of antibiotic resistance bacteria (ARB) generation should be considered in the disposal process. High-throughput quantitative PCR (HT-qPCR) and 16S rRNA gene sequencing were performed to investigate the effect of PFD on the dynamics of antibiotic resistance genes (ARGs) and bacterial community during a lab-scale soil experiment. After the application of PFD, the bacterial number and diversity showed an obvious decrease in the initial days. The abundances of Streptomyces and Bacillus, which are the most widespread predicted source phyla of ARGs, increased remarkably from 4.42% to 2.59%–22.97% and 21.35%. The increase of ARGs was observed during the PFD application and the ARGs carried by PFD itself contributed to the initiation of soil ARGs. The results of redundancy analysis (RDA) show that the shift in bacterial community induced by variation of penicillin content is the primary driver shaping ARGs compositions.

In this study, degradation affinities of 14 antibiotics and one metabolite were determined in batch experiments. A modelling framework was applied to decrypt potential ranges of abiotic, biotic and photolytic degradation coefficients. In detail, we performed batch experiments with three different sewages in the dark at 7 °C and 22 °C. Additionally, we conducted further batch experiments with artificial irradiation and different dilutions of the sewage at 30 °C – de novo three different sewages were used. The batch experiments were initially spiked with a stock solution with 14 antibiotics and one metabolite to increase background concentrations by 1 μg L−1 for each compound. The final antibiotic concentrations were sub-inhibitory with regard to sewage bacteria. The here presented modelling framework based on the Activated Sludge Model No. 3 in combination with adsorption and desorption processes. The model was calibrated with monitored standard sewage compounds before antibiotic degradation rates were quantified. The model decrypted ranges of abiotic, biotic and photolytic degradation coefficients. In detail, six antibiotics were not abiotic degradable at 7 °C, five antibiotics not at 22 °C and only 2 antibiotics at 30 °C. Finally, nine antibiotics were not significantly biodegradable at 7 °C and 22 °C. The model determined the link between adsorption characteristics and biodegradation rates. In detail, the rate was significantly affected by the bio-solid partition coefficient and the duration until adsorption was balanced. All antibiotics and the metabolite were photolytic degradable. In general, photolytic degradation was the most efficient elimination pathway of presented antibiotics except for the given metabolite and penicillin antibiotics.

Combining hydrothermal treatment and composting is an effective method to dispose of penicillin fermentation residue (PFR), but the safety and related mechanism are still unclear. In this study, penicillin solution was hydrothermally treated to decipher its degradation mechanism, and then hydrothermally treated PFR (HT-PFR) was mixed with bulking agents at ratios of 2:0 (CK), 2:1.5 (T1), and 2:5 (T2) to determine the absolute abundance of antibiotic resistance genes (ARGs) and the succession of bacterial community. Results showed that penicillin was degraded to several new compounds without the initial lactam structure after hydrothermal treatment. During composting, temperature and pH of the composts increased with the raising of HT-PFR proportion, except the pH at days 2. After 52 days of composting, the absolute copies of ARGs (blaTEM, blaCMY2, and blaSFO) and the relative abundance of bacteria related to pathogens were reduced significantly (P < 0.05). Especially, the total amount of ARGs in the samples of CK and T1 were decreased to equal level (around 5 log₁₀ copies/g), which indicated that more ARGs were degraded in the latter by the composting process. In the CK samples, Bacteroidetes and Proteobacteria accounted for ~69.8% of the total bacteria, but they were gradually replaced by Firmicutes with increasing proportions of HT-PFR, which can be caused by the high protein content in PFR. Consisting with bacterial community, more gram-positive bacteria were observed in T1 and T2, and most of them are related to manganese oxidation and chitinolysis. As composting proceeded, bacteria having symbiotic or pathogenic relationships with animals and plants were reduced, but those related to ureolysis and cellulolysis were enriched. Above all, hydrothermal treatment is effective in destroying the lactam structure of penicillin, which makes that most ARGs and pathogenic bacteria are eliminated in the subsequent composting.

Veterinary antibiotics are widely used in livestock production and can be released to the environment via manure, affecting non-target organisms. Recent studies provide evidence that antibiotics can adversely affect both plants and insects but whether antibiotics in soil also affect trophic interactions is unknown.We tested whether antibiotics grown in sand as soil substitute with environmentally relevant concentrations of penicillin, sulfadiazine and tetracycline affect the survival of aphids feeding on plants (two crop and one non-crop plant species). Apera spica-venti, Brassica napus, and Triticum aestivum individuals were infested with aphids that were monitored over four weeks. We did not observe effects of penicillin or tetracycline on plants or aphids. However, sulfadiazine treatments reduced plant growth and increased mortality in the two tested grass species, but not in B. napus. Sulfadiazine subsequently decreased aphid density indirectly through reduced host plant biomass. We thus show that an antibiotic at realistic concentrations in a soil substitute can affect several trophic levels, i.e. plants and herbivores. This study contributes to the environmental risk assessment of veterinary antibiotics as it implies that their use potentially affects plant-insect interactions at environmentally relevant concentrations.

The present study aimed to use primary liver cell culture derived from the orange-spotted grouper, Epinephelus coioides, to assess the toxic effects of nonylphenol (NP) on the hepatocyte viability and the liver antioxidant system. E. coioides was selected due to its commercial importance. NP was used in this study because of its high potential of producing oxidative stress due to increased reactive oxygen species (ROS). A liver of E. coioides was digested with PBS containing 0.1% collagenase IV. The digested cells were moved to Leibovitz L-15 culture medium with 20% fetal bovine serum (FBS), 100IUmL−1 penicillin, 100μgmL−1 streptomycin. Aliquots of cell suspension were seeded as a monolayer into sterile 25cm2 tissue culture flasks and incubated at 30°C for 14days. The medium, containing non-attached cells, was removed after 24 to 48h and a new medium was added. The IC50 of 10−4molL−1 was determined for nonylphenol using MTT assay. Cells were then incubated with L-15 medium containing 10−5, 2×10−5, 3×10−5molL−1 of NP and samples were taken after 6, 12 and 24h of incubation for analysis of LPO, SOD, CAT, GPx, LDH, AST, ALT, and ALP. Based on the results, the lowest concentration of NP was not markedly cytotoxic to primary hepatocytes and the cell sensitivity to NP increased dose-dependently. The activities of SOD, CAT and GPx decreased significantly, while activities of LPO, LDH, AST, ALT and ALP, increased significantly in a dose-related pattern in NP-treated cells. In conclusion, this study revealed that NP could induce the oxidative stress in cultivated hepatocytes of E. coioides during a short-term exposure. NP toxicity is mainly due to the induction of the reactive oxygen species (ROS), which lead to cell membrane disruption, damage of cellular metabolism, and interference with cellular macromolecules.

Escherichia coli isolates, commonly found as gut microflora in warm-blooded animals, are classified into the major phylogroups, A, B1, B2 and D, and further divided into subgroups: A0, A1, B1, B2₂, B2₃, D1 and D2. This study tracks and classifies E. coli strains along an integrated algal pond system (IAPS) during municipal sewage treatment. PCR-confirmed E. coli isolates were delineated into phylogroup by targeting genes chuA, yjaA and TSPE4.C2 using the triplex PCR assay. Antimicrobial susceptibility testing was by disk diffusion assay. A total of 120 E. coli isolates were confirmed by analysis of the uidA gene. Phylogenetic analysis revealed 57 isolates were group A with others in groups B2 (35), B1 (16) and D (12). Isolate susceptibility to antibiotics was norfloxacin > florfenicol > gatifloxacin > streptomycin > gentamicin. Nearly all isolates (117, 98%) were sulphamethoxazole- and penicillin G-resistant (115, 96%). Thus, resistance was manifest by all phylogroups and to 3–17 of drugs tested. These findings confirm presence of various multidrug-resistant E. coli phylogroups throughout the IAPS wastewater treatment process and emphasize the usefulness of multidrug resistance profiling as a tool for microbial source tracking and, with which to determine origin of faecal pollution.

This study investigates levels of bacteria through population indicators as well as the levels of antibiotic-resistance bacteria in dairy manure. Although overall bacteria levels may be reduced during manure processing, it is of interest whether changes in management practices could lead to increased levels of antibiotic-resistance bacteria, which are becoming more prevalent in agricultural soils, groundwater, and surface water. Appropriate manure treatments are needed not only to reduce the potential risk of exporting antibiotic-resistant bacteria to an environment, but also reduce antibiotic-resistant bacteria exposure to animals if processed water is recycled. Results from this research revealed manure separation under relatively low speed centrifuge with 100 ppm polyacrylamide (PAM) emulsion addition reduced bacteria indicators population such as total coliforms and Escherichia coli (E. coli) significantly in the liquid stream compared to no PAM added. However, the percentages of antibiotic-resistant isolates in liquid stream after centrifuge with PAM were higher compared to raw manure and no PAM added. Antibiotic resistance (cephalosporin, florfenicol, penicillin, or tetracycline) was observed or 65.38% of bacterial isolates in manure from a large dairy farm in Wisconsin and 39.29% of isolates demonstrated multidrug resistance. The results from this study strongly suggest that appropriate manure treatment is essential in order to help minimize the abundance of antibiotic resistance in our water environment.

Marine fish species were analyzed for culturable and total metagenomic microbial diversity, antibiotic resistance (AR) pattern, and horizontal gene transfer in culturable microorganisms. We observed a high AR microbial load of 3 to 4 log CFU g⁻¹. Many fish pathogens like Providencia, Staphylococcus, Klebsiella pneumoniae, Enterobacter, Vagococcus, and Aeromonas veronii were isolated. Photobacterium and Vibrio were two major fish and human pathogens which were identified in the fish metagenome. Other pathogens that were identified were Shewanella, Acinetobacter, Psychrobacter, and Flavobacterium. Most of these pathogens were resistant to multiple antibiotics such as erythromycin, kanamycin, neomycin, streptomycin, penicillin, cefotaxime, bacitracin, rifampicin, trimethoprim, ciprofloxacin, and doxycycline with a high multiple antibiotic resistance index of 0.54–0.77. The fish microflora showed high prevalence of AR genes like bla TEM, Class I integron, tetA, aph(3′)-IIIa, ermB, aadA, and sul1. Nineteen of 26 AR isolates harbored Class I integrons showing high co-resistance to trimethoprim, kanamycin, doxycycline, and cefotaxime. Mobile R-plasmids from 6 of the 12 AR pathogens were transferred to recipient E. coli after conjugation. The transconjugants harbored the same R-plasmid carrying bla CTX₋M, dfr1, tetA, bla TEM, and cat genes. This study confirms that fish is a potential carrier of AR pathogens which can enter the human gut via food chain. To the best of our knowledge, this is the first study in the Indian subcontinent reporting a direct evidence of spread of AR pathogens to humans from specific marine fish consumption.

Antibiotic residues in soils can lead to serious health risk and ecological hazards. In this study, the effects of penicillin and neomycin, two antibiotics widely used in animal production, were investigated on soil bacterial communities. Changes in the community structure were monitored using three 16S ribosomal DNA (rDNA) polymerase chain reaction-based approaches, including denaturing gradient gel electrophoresis (DGGE), amplified rDNA restriction analysis (ARDRA), and terminal-restriction fragment length polymorphism (T-RFLP) analysis. The prominent DGGE bands were excised from gels and sequenced, and the data indicated the prevalence of Gammaproteobacteria in the soils. The total soil bacterial community, including uncultured bacteria, exhibited a higher diversity than that of cultured bacteria. Some microbial strains were capable of surviving and even subsisting on penicillin or neomycin. We also observed toxic effects of the antibiotics on the indigenous soil bacterial communities since some genotypes disappeared after the treatments (e.g., Pseudomonas sp., Stenotrophomonas sp., Salinimonas, and uncultured Acinetobacter sp.). The implications of these findings are that the functions of soil bacterial communities may be negatively affected if key microbial community members are lost.