Search

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Overuse of heavy metal and antibiotics in livestock husbandry has led to the accumulation of heavy metal resistance genes (HMRGs) and antibiotic resistance genes (ARGs) in environment. This research aims to reveal the variation of heavy metal speciation and potential horizontal gene transfer (HGT) of HMRGs and ARGs in manure composting under different initial chlortetracycline (CTC) concentrations. Treatments spiked with 20 mg/kg CTC (treatment P1), 100 mg/kg CTC (treatment P2), and the control (treatment CK) were operated. Results showed that CTC could be completely removed in the thermophilic phase of all the treatments despite of the initial concentrations. Bioavailable Cu in treatments CK, P1, and P2 declined by 14.5%, 27.1%, and 26.7% and bioavailable Zn declined by 15.3%, 29.5%, and 12.1%, respectively, after the composting, respectively. Relative abundance of HMRGs decreased by 6.49 log, 8.88 log, and 5.77 log, respectively, in treatments CK, P1, and P2. Relative abundance of ARGs decreased by 3.37 log, 4.86 log, and 3.32 log, respectively, in treatments CK, P1, and P2. Composting could effectively reduce genes pcoD, pcoA, zntA, tetQ, and tetA, which might locate on the same plasmid. CTC of 100 mg/kg promoted the co-selection of ARGs and HMRGs and increased the potential HGT of gene cusA. [ABSTRACT FROM AUTHOR]

Veterinary antibiotics, including erythromycin (Ery) and chlortetracycline (CTC), are often detected in agricultural land. Although these contaminants affect plant growth and development, their effects on crops remain elusive. In this study, the effects of Ery and CTC on plant growth were investigated and compared by analyzing transcript abundance in Brassica campestris seedlings. Treatment with Ery and/or CTC reduced chlorophyll content in leaves and photosynthetic efficiency. Examination of the chloroplast ultrastructure revealed the presence of abnormally shaped plastids in response to Ery and CTC treatments. The antibiotics produced similar phenotypes of lower accumulation of photosynthetic genes, including RBCL and LHCB1.1. Analysis of the transcript levels revealed that Ery and CTC differentially down-regulated genes involved in the tetrapyrrole biosynthetic pathway and primary root growth. In the presence of Ery and CTC, chloroplasts were undeveloped and photosynthesis efficiency was reduced. These results suggest that both Ery and CTC individually affect gene expression and influence plant physiological activity, independently of one another.

Nowadays, the residual heavy metals and antibiotics in water and soil have a potential threat to human being health, thereby their purification is of great importance. In this study, the application of Cr6+ and chlortetracycline (CTC) removal using a new fruit peel based biochar composite (FPBC) had been explored. Batch experiments results showed that FPBC presented excellent removal performance on Cr6+ and CTC, and the simultaneous removal efficiencies of Cr6+ and CTC were 97% and 81% within 180 min, respectively. The adsorption kinetics and isotherms of Cr6+ by FPBC could be well described by the pseudo-second-order and Langmuir models, respectively, and its adsorption was a spontaneous endothermic process. The inhibitory of the coexisting anions on Cr6+ removal of followed the order of HPO 4 3-> HCO 3 -> SO 4 2->NO 3 -> Cl-. The simultaneous removal of Cr6+ and CTC by FPBC had been achieved at low CTC content levels. The presence of NaCl showed a significant inhibitory on Cr6+ removal but a positive effect on CTC removal at low content level. A potential reaction mechanism of both Cr6+ and CTC removal over FPBC was proposed on the basic of the comprehensive characterizations and adsorption performance. Both reduction and surface precipitation reactions might be dominant in Cr6+ removal process, whereas both complexation and hydrogen bond interaction might be mainly responsible for CTC removal. These findings suggested that this fruit peel based biochar composite might be a promising material for the remediation of Cr6+ and CTC-contaminated wastewater. [Display omitted] • A new fruit peel based biochar composite (FPBC) was firstly synthesized. • Cr6+ adsorption was well described by pseudo-second-order and Langmuir models. • NaCl showed an inhibitory on Cr6+ removal but a positive effect on CTC removal. • FPBC presented a high simultaneous removal of Cr6+ and CTC. • A potential mechanism for Cr6+ and CTC removal over FPBC was proposed. [ABSTRACT FROM AUTHOR]

In this study, the removal mechanism of chlortetracycline (CTC) by nanoscale zero valent iron (nZVI) from the aqueous solutions. Experimental variables such as solution pH, nZVI dosage, contact time and reaction temprature were systematically studied and the degradation products of CTC were determined at optimum operating conditions which provided to maximum CTC removal percentages. Adsorption behavior depended pH and maximum removal of CTC occured at pH 6. The optimum dosage was 0,4 g/L because there was no significant removal efficiency when nZVI dosage was between 0,4-0,6 g/L. Adsorption kinetics exhibited that equilibrium was reached within 2 h following the pseudo-second order model. [ABSTRACT FROM AUTHOR]

Tetracycline antibiotics represent one of the most successful classes of pharmaceuticals and are extensively used around the world for human and veterinary health. Ozone-based processes have emerged as a selective water treatment process for many pharmaceuticals. The primary objective of this study was to determine the reaction kinetics for transformation of five tetracycline antibiotics (i.e., chlortetracycline, doxycycline, oxytetracycline, rolitetracycline, and tetracycline) by ozone across the pH2 to 9 range. The apparent second-order rate constant for tetracycline was on the order of 1–6×104 M−1 s−1 at low pH, and 0.6–2.0×106 M−1 s−1 at near neutral pH. The apparent second-order rate constants did not fit a conventional pKa -based model, presumably due to the complex acid/base speciation of tetracycline antibiotics. A model that considers the net charge on tetracycline molecules in solution provided a nice fit to experimental data for all five tetracyclines. The five tetracycline antibiotics demonstrated similar reaction kinetics with ozone, and a cumulative analysis of all kinetics data provides a baseline model for other tetracycline compounds. The ozone exposure required for complete transformation of tetracycline antibiotics (10−5 M−s) is well below that achieved during ozone disinfection processes (10−3 M−s), indicating that ozone is an effective treatment for tetracycline antibiotics. [ABSTRACT FROM AUTHOR]

Abstract: In this paper two fast and highly sensitive ultra-high performance liquid chromatography (UHPLC) methods for the determination of tetracycline antibiotics (oxytetracycline, tetracycline, doxycycline, demeclocycline, chlortetracycline, minocycline and degradation product epitetracycline) in surface waters have been developed using fluorescence (FL) and mass spectrometry (MS) detection. ACQUITY UPLC BEH C8 and ACQUITY CSH C18 columns were employed for FL and MS detection, respectively, both packed with 1.7μm particles. Mixed-mode separation mechanism of CSH (charged surface technology) sorbent was found particularly useful in analysis of TCs, which possess problematic amphoteric structures. The FL methodology was based on chelation of tetracyclines with calcium ions to perform on-column derivatisation. The developed methods were compared in the terms of validation parameters including linearity, sensitivity, precision and accuracy. The linearity range for FL detection was within 7ngmL−1 to 50μgmL−1 with method limit of detection (MLOD) as low as 0.2ngmL−1 for most of the analytes. MS detection showed even higher sensitivity reaching MLOD of 0.003ngmL−1, which is the highest sensitivity reported so far in analysis of TCs. Matrix matched calibration curves in the range of 0.01–50ngmL−1 were used for quantification to compensate for matrix effects with the correlation coefficients demonstrating good linearity (0.9940–0.9999). The extraction of the antibiotics from surface waters was performed using solid phase extraction with Oasis HLB cartridges. Accuracy was expressed as recovery with values ranging from 96.52% to 127.30% and from 91.66% to 123.70% for FL and MS detection, respectively. [Copyright &y& Elsevier]

Abstract: Copper-doped titania (Cu/TiO2) hollow microspheres were fabricated using the rape pollen as biotemplates via an improved sol–gel method and a followed calcinations process. In the fabricated process, a titanium(IV)-isopropoxide-based sol directly coated onto the surface of rape pollen. Subsequently, after calcinations, rape pollen was removed by high temperature and the hollow microsphere structure was retained. The average diameter of as-obtained hollow microspheres is 15–20μm and the thickness of shell is approximately 0.6μm. Knowing from XRD results, the main crystal phase of microspheres is anatase, coupled with rutile. The specific surface area varied between 141.80m2/g and 172.51m2/g. This hollow sphere photocatalysts with high specific surface area exhibited stronger absorption ability and higher photoactivity, stimulated by visible light. The degradation process of chlortetracycline (CTC) solution had been studied. The degradated results indicate that CTC could be effective degradated by fabricated hollow spherical materials. And the intermediate products formed in the photocatalytic process had been identified. [Copyright &y& Elsevier]

Abstract: This work studies the inhibitory effects and fate of the antibiotics oxytetracycline (OTC) and chlortetracycline (CTC) during the anaerobic digestion of pig manure. Both substances were added together in batch assays at concentrations of 10, 50 and 100mgL−1. Control assays only with antibiotics (abiotic) as well as without antibiotics (biotic) were also conducted. Methane production was reduced by 56%, 60% and 62% at OTC and CTC concentrations of 10, 50 and 100mgL−1, respectively. The IC50 level calculated from these experiments was estimated to be around 9mgL−1, a significant value considering the reported concentrations of these compounds in pig manure samples (up to 136mgL−1). Strong adsorption to solid matter was observed, which increased the stability of both substances. Antibiotic degradation was thus much higher in control assays, without solids, than those determined from assays including inoculum and manure substrate. [ABSTRACT FROM AUTHOR]

Human and veterinary drugs are continually being released in the environment mainly as a result of manufacturing processes, disposal of unused or expired products, and excreta. Because of their physical and chemical properties, many of these substances or their bioactive metabolites end up in soils and sediments, where they can accumulate and induce adverse effects in terrestrial or aquatic organisms. Among these effects, bacterial resistance is increasingly observed and is caused by the extensive use of antibiotics in animal and fish farming and the growing practice of adding manure and sewage sludge to agricultural fields, which is of particular concern. Literature on the environmental analysis and occurrence of drugs has addressed a very small percentage of these compounds, so very little information is available about the fate and the potential effects of drugs in the environment. This article presents an overview of recent developments in the determination of veterinary and human drugs in solid environmental matrices, including soil, sediment and sludge. The analysis of pharmaceuticals in the such samples has always been carried out by high-performance liquid chromatography coupled to ultraviolet detection, and, to a lesser extent, to mass spectrometry and fluorescence detection. In most cases, sample pretreatment includes extraction of the solid sample and further purification of the extract by solid phase extraction with C18 sorbents. In addition to analytical articles, this overview includes papers concerning usage of drugs, as well as sources, fate, persistence, and effects of pharmaceuticals in solid environmental matrices. [Copyright &y& Elsevier]

Veterinary antibiotics, including erythromycin (Ery) and chlortetracycline (CTC), are often detected in agricultural land. Although these contaminants affect plant growth and development, their effects on crops remain elusive. In this study, the effects of Ery and CTC on plant growth were investigated and compared by analyzing transcript abundance in Brassica campestris seedlings. Treatment with Ery and/or CTC reduced chlorophyll content in leaves and photosynthetic efficiency. Examination of the chloroplast ultrastructure revealed the presence of abnormally shaped plastids in response to Ery and CTC treatments. The antibiotics produced similar phenotypes of lower accumulation of photosynthetic genes, including RBCL and LHCB1.1. Analysis of the transcript levels revealed that Ery and CTC differentially down-regulated genes involved in the tetrapyrrole biosynthetic pathway and primary root growth. In the presence of Ery and CTC, chloroplasts were undeveloped and photosynthesis efficiency was reduced. These results suggest that both Ery and CTC individually affect gene expression and influence plant physiological activity, independently of one another. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effect of probiotics (Lactobacillus planetarium) relative to chlortetracycline (CTC) supplementation on growth performance, nutrient digestibility, fecal microbiota, fecal score and noxious gas emission in weaning pigs. A total of 135 weanling pigs with an average body weight of 6.61 kg and 28 ± 1 d of age were used in a 6-week feeding trial. The three treatments were (i) CON; control group, feeding with basal diet; (ii) CL; Control + 0.06% probiotic (1.2 × 109 cfu kg−1 of viable L. planetarium) (iii) AT; Control + 0.01% Antibiotic. The dietary supplementation with probiotic or CTC increased (P < 0.05) the body weight (BW), average daily gain (ADG) and gain: feed (G: F) compared with basal diet during 3-6 weeks. Additionally, the CTC group showed significantly higher (P < 0.05) BW, ADG and G: F than probiotic group. During the overall experimental period, pigs fed probiotic or CTC supplemented diet showed higher ADG (P < 0.05) than pigs fed basal diet, the G: F ratio in CTC group was higher (P < 0.05) than basal diet and probiotic group. In the 6th week, the apparent total tract digestibility (ATTD) of nitrogen increased (P < 0.05) for the probiotic or CTC group, the CTC group showed significantly higher (P < 0.05) ATTD of N than probiotic group. The dietary supplementation with CTC or probiotic decreased (P < 0.05) the E. coli counts on d 42. The CTC group showed lower (P < 0.05) E. coli counts than probiotic group. There was no significant difference in gas emission and diarrhea score in all treatments. Probiotic (L. planetarium) at 600mg kg−1 concentration can be suggested as an alternative to growth-promoting probiotics. [ABSTRACT FROM AUTHOR]