抗生素专用消泡剂的研制

本文通过对国内生产抗生素类产品企业所用消泡剂的调研,在原有研制消泡剂经验的基础上,研制出了抗生素专用消泡剂,从而取代了进口产品,填补了国内空白.     

A Novel Biocidal Nanocomposite: Spherical Silica with Silver Ions Anchored at the Surface

This article is devoted to a novel class of antimicrobial agents: nanocomposites composed of spherical silica and silver ions located at the silica’s surface with the assumed distribution. Such materials are in high demand due to the increasing threat from bacterial strains that are becoming resistant to currently known antibiotics. In particular, we focus on materials that make it possible to limit the growth of bacterial colonies on a variety of tactile surfaces. In this paper, we present a method for preparing a silica-based nanocomposite containing silver ions and the analysis of their antimicrobial properties. Our research revealed that the presence of tested nanocomposite induces very high oxidative stress in the bacteria cell, damaging and modifying bacterial DNA, creating oxidized guanines, cytosines, or adenines, which causes its very rapid destruction, leading to cell death.     

An Original and Efficient Antibiotic Adjuvant Strategy to Enhance the Activity of Macrolide Antibiotics against Gram-Negative Resistant Strains

Gram-negative bacteria were reported as a significant cause of infections in both community and nosocomial settings. Considered as one of the greatest threats to public health, the spread of bacteria drug resistance and the lack of effective alternative treatment options remains problematic. Herein, we report a promising strategy to combat Gram-negative resistant strains consisting of the combination of a macrolide antibiotic with a polyaminoisoprenyl adjuvant derivative leading to a significant decrease of antibiotic resistance.     

Photocatalytic removal of heavy metal ions and antibiotics in agricultural wastewater: A review

In recent years, the treatment of agricultural wastewater has been an important aspect of environmental protection. The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to stimulate the migration of photocarriers to the surface of photocatalysts and occur reduction-oxidation reaction with pollutants in agricultural wastewater. Photocatalytic technology has the characteristics of high efficiency, sustainability, low-energy and free secondary pollution. It is an environmental and economical method to recover water quality that only needs sunlight. In this paper, the mechanism and research progress of photocatalytic removal of heavy metal ions and antibiotics from agricultural water pollution were reviewed by combining photocatalytic degradation process with agricultural treatment technology. The mechanism of influencing factors of photocatalytic degradation efficiency was discussed in detail and corresponding strategies were proposed, which has certain reference value for the development of photocatalytic degradation.     

Adsorption of oxytetracycline from aquaculture wastewater by modified carbon nanotubes: kinetics,isotherms and thermodynamics

Abstract

In the present study, lanthanum modified carbon nanotubes (La-CNTs) were prepared by the impregnation method and used as adsorbents to remove oxytetracycline (OTC) from aquaculture wastewater. La-CNTs were characterized by SEM, EDS, XRD, BET analysis. The effects of adsorbent dosage, concentration of OTC, adsorption time, pH and interfering ions on the adsorption of OTC by La-CNTs were investigated. The optimum adsorbent dosage, OTC concentration, adsorption equilibrium time and pH for OTC adsorption by La-CNTs are 0.03?g, 20?mg/L, 180?min and 7, respectively. The outcome of the kinetics studies showed a significant linear correlation between the experimental results and the quasi-second-order kinetics model. As an adsorption isotherm model, the Langmuir model showed a very good consistency with the adsorption of OTC by La-CNTs, as the maximum adsorption quantity reached 117.23?mg/g. Through the thermodynamic analysis showed that the adsorption of OTC by La-CNTs was an endothermic process of entropy increase, which occurs spontaneously. The predominant forces promoting this adsorption were van der Waals force, π-π electron donor-acceptor interaction, and electrostatic interaction.     

鱼源藤黄微球菌三重PCR检测法的建立及耐药性分析

为鉴定感染黄颡鱼菌株fsznc-CL、建立一种快速检测的方法和探讨其耐药特性。采用形态学、理化特性及16S rDNA序列分析方法进行菌株鉴定,人工回归感染研究其致病性。通过对三对特异性引物的反应体系和条件进行优化,建立一种三重PCR检测法并应用到人工感染黄颡鱼的检测中。运用PCR方法扩增耐药基因,用琼脂纸片扩散法检测该菌的药敏特性。结果表明,分离菌株fsznc-CL为藤黄微球菌(Micrococcus luteus),该菌对黄颡鱼具有一定的致病性。三重PCR检测法可准确扩增出藤黄微球菌CBS、Sig和Pol三对目的基因,而其他菌株未扩增出,检测该菌的最低模板浓度为5.822×10^-3 ng/μL,该方法检测带菌样品的阳性率约为83.33%。该菌携带了TEM、aph(3')-Ⅱa、aac(6')-Ⅰ、Sul1和Sul2耐药基因。菌株fsznc-CL对诺氟沙星、苯唑西林、红霉素和呋喃唑酮耐药。本试验建立的三重PCR检测法具有较高的特异性和灵敏度,目前藤黄微球菌对少部分抗生素耐药。     

抗生素瓶塞中重金属含量测定方法的改进

抗生素瓶塞中重金属主要有铅、镉、锑等。重金属的含量通常是以测定其硫化物的含量来判定的。重金属含量是否合格是控制瓶塞质量的一项重要指标。     

QUALITY INTERACTION IN A JET SPOUTED BED DRYER FOR BIO-PRODUCTS

An experimental study was conducted to apply the jet spouted bed (JSB) dryer with inert bodies for drying of fodder antibiotic; (zinc-salt bacitracin and tylosin) and baker's yeast which are extracted from fermentation broth. After establishing the drving properties of these products (e.g. sorption isotherm, water activity and thermostability), the influence of basic drying parameters (temperature of drying agent, bed loading, gas flow rate) on drying characteristics and quality of the products was determined. The results proved that a JSB dryer may be successfully applied to fodder antibiotics; especially to Zn-bacitracin; however, for a highly labile live organism like baker's yeast, this method cannot be used. The optimal parameters for drying of Zn-bacitracin have been presented.     

高效液相色谱法测定动物组织中四环素族抗生素残留

建立了一种使用高效液相色谱同时测定动物组织中土霉素(OTC)、四环素(TC)和金霉素(CTC)残留的方法。样品的预处理采用5%高氯酸溶液去除样品中蛋白质。采用Kromasil C18柱(250×4.6mm,5μm);0.01mol/L NaH2PO4.2H2O(pH=3)—60/40的乙腈/水(v/v)为流动相;流速1.0mL/min;检测波长为355nm;梯度洗脱。四环素族抗生素(TCs)的回收率在89.4%～101.2%之间,相对标准偏差RSD在1.41～3.50%。本方法可靠、灵敏、经济、快速。