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Abstract Coexistence of antibiotics/heavy metals and the overexpression of resistance genes in the vermicompost has become an emerging environmental issue. Little is known about the interaction and correlation between chemical pollutants and biological macromolecular compounds. In this study, three typical vermicompost samples were selected from the Yangtze River Delta region in China to investigate the antibiotic, heavy metal and corresponding antibiotic resistance genes (ARGs) and heavy metal resistance genes (HRGs). The results indicated the prevalence of tetracycline (TC), copper (Cu), zinc (Zn), cadmium (Cd), corresponding TC-resistance genes (tet A, tet C, tet W, tet M, tet O, and tet S) and HRGs (cop A, pco A, cus A, czc A, czc B, and czc R) in the three vermicompost samples. In addition, the ARG level was positively associated with the water-soluble TC fraction in the vermicompost, and it was same between the HRG abundance and exchangeable heavy metal content (p < 0.05). Moreover, a positive correlation was found between ARG and HRG abundance in the vermicompost samples, suggesting a close regulation mechanism involving the expression of both genes. The result obtained here could provide new insight into the controlling risk of heavy metals, TC, and relevant resistance genes mixed contamination in the vermicompost. Graphical abstract Image 1 Highlights • Tetracycline, heavy metals, and resistance genes co-existed in vermicomposts. • Antibiotic resistance gene level positively associated with the water-soluble TC fraction. • Heavy metal resistance gene level positively correlated with the exchangeable heavy metal species. • Significant positive correlation was observed between antibiotic- and heavy metal-resistance genes. Tetracycline, heavy metals, and associated resistance genes co-existed and positively correlated with each other in typical vermicomposts from Yangtze River Delta region in China. [ABSTRACT FROM AUTHOR]

Abstract Soil contamination with antibiotics and antibiotic resistant bacteria/genes (ARB/ARGs) has becoming an emerging environmental problem. Moreover, the mixed pollutants' transfer and accumulation from soil to tuberous vegetables has posed a great threat against food security and human health. In this work, the application of two absorbing materials (maize biochar and sulfate modified eggshell) was able to reduce the poisonous effect of soil antibiotics on potato root system by stimulate the dissipation of water-soluble antibiotics in soil; and also improve food quality by increasing potato starch, protein, fat, and vitamins. Meanwhile, both amendments could effectively decrease the classes and the accumulative abundance of ARB and ARGs (sul I, sul II, cat I, cat II, erm A, erm B) in the edible parts of potato. The lowest abundance of ARGs was detected in the biochar application treatment, with the accumulative ARG level of 8.9 × 102 and 7.2 × 102 copies mL−1 in potato peel (sul l + cat I + erm A) and tuberous root (sul I), respectively. It is the first study to demonstrate the feasibility of biochar and eggshell derived from agricultural wastes as green absorbing materials to reduce soil antibiotic, ARB, and ARGs accumulation risk in tuberous vegetable. Graphical abstract Image 1 Highlights • Biochar or eggshell impeded soil antibiotics accumulation in potato effectively. • ARB isolates in potato decreased significantly after biochar or eggshell addition. • ARG accumulation risk was limited in potato with biochar or eggshell amendment. • Impedance effect of biochar was more effective than that of eggshell. • Biochar or eggshell application provided new strategy to ensure vegetable security. ARB and ARG accumulation risk was limited in potato with biochar or eggshell amendment; Impedance effect of biochar was more effective than that of eggshell. [ABSTRACT FROM AUTHOR]

High abundances of antibiotic-resistant pathogenic bacteria (ARPB) and antibiotic resistance genes (ARGs) in agricultural soil-plant systems have become serious threats to human health and environmental safety. Therefore, it is crucial to develop targeted technology to control existing antibiotic resistance (AR) contamination and potential dissemination in soil-plant systems. In this work, polyvalent bacteriophage (phage) therapy and biochar amendment were applied separately and in combination to stimulate ARPB/ARG dissipation in a soil-lettuce system. With combined application of biochar and polyvalent phage, the abundance of Escherichia coli K-12 (tet R ) and Pseudomonas aeruginosa PAO1 (amp R + fos R ) and their corresponding ARGs ( tet M, tet Q, tet W, amp C, and fos A) significantly decreased in the soil after 63 days' incubation ( p  < 0.05). Similar results for endophytic K-12 and PAO1, and ARGs, were also obtained in lettuce tissues following combined treatment. Additionally, high throughput sequencing revealed that biochar and polyvalent phage synergetically improved the structural diversity and functional stability of the indigenous bacterial communities in soil and the endophytic ones in lettuce. Hence, this work proposes a novel biotechnology that combines biochar amendment and polyvalent phage therapy to achieve targeted inactivation of ARPB, which stimulates ARG dissipation in soil-lettuce systems. [ABSTRACT FROM AUTHOR]

Abstract: The paper has discussed the voice prediction research based on biological and medical research. From all-pole model, we create speech transform model and predicate voice signal. The Levinson recursion was introduce to this model, the experiment proved the method is feasible and effective. [Copyright &y& Elsevier]