涡轮萃取塔在林可霉素萃取中的应用研究

林可霉素是一种高效广谱抗生素,有着广泛的应用。目前在工业生产中,大多采用多级混合澄清槽从发酵液中萃取林可霉素,但混合澄清槽存在占地面积大、溶剂储存量大、操作费用高,操作环境差等问题。涡轮萃取塔是一种高效的萃取塔,有着占地面积小、溶剂储存量低、萃取效率高等优点。在直径50 mm小型涡轮萃取塔中对林可霉素进行了研究:在不同相比、不同转数条件下,研究了林可霉素的传质情况及液滴直径大小分布特征。实验结果表明:在相同流量的情况下,随着转速增高,分散相滞留率随之增高,林可霉素的萃取效果越好。在相同转速、轻相流量不变的情况下,重相流量越低,林可霉素的萃取效果越好。研究结果表明:涡轮萃取塔用于林可霉素的萃取是可行的。     

Determination of Ozonation Rate Constants for Lincomycin and Spectinomycin

Recent occurrences of pharmaceutical antibiotics in surface water, drinking water, and wastewater systems have gained significant attention due to their potential threats to human health. This study determined the absolute second-order rate constants of ozone with two amine-based antibiotics, namely, lincomycin and spectinomycin, using the stopped-flow technique under controlled ionic strength, buffer, and temperature. Results indicate that ozone reacts quickly with the selected antibiotics, and the reaction rate significantly depends on solution pH. For lincomycin, ozone attacks its free amine group and sulfur group with absolute rate constants of 2.76 × 10⁶ M^?1·s^?1 (for neutral form) and 3.26 × 10⁵ M^?1·s^?1 (for monoprotonated form), respectively. For spectinomycin, ozone attacks two free amine groups with absolute rate constants of 1.27 × 10⁶ M^?1·s^?1 (for neutral form) and 3.30 × 10⁵ M^?1·s^?1 (for monoprotonated form), respectively. These rate constants have been corrected to zero ionic strength. Protonated amine is nonreactive toward ozone. Model prediction indicates that lincomycin and spectinomycin can be effectively transformed by ozonation processes around neutral pH.     

Use of long-chain alcohol in extraction and purification of lincomycin from fermentation broth

Low selectivity for lincomycin in butanol extraction process leads to relatively higher content of impurities. A novel process for extraction of lincomycin from fermentation broth was studied in this work. Mixture of n-octanol and n-decanol is used as extradant to replace n-butanol in extraction of lincomycin. Optimal operation conditions for the process have been studied. Due to higher extraction selectivity for lincomycin A by long-chain alcohol, content of impurity (lincomycin B) in the final product is much lower than that in product by butanol process. Furthermore, the practicability for combination of long-chain alcohol and butanol in purification of lincomycin was investigated.     

Lincomycin solar photodegradation, algal toxicity and removal from wastewaters by means of ozonation

Antibiotic molecules have been reported among the xenobiotics present at trace levels in sewage treatment plant (STP) effluents and aquatic environment. Lincomycin, one of the most used in clinical practices whose presence in the STP effluents has been often documented, is submitted to an extensive investigation to assess its persistence in the environment and toxicity towards different algal strains. The possibility to remove the lincomycin from water by means of ozonation is demonstrated and a reduction of toxicity of ozonated solutions on S. leopoliensis, with respect to untreated solutions containing this compound, is obtained even just for 1h of treatment. Kinetic constants for the attack to lincomycin of ozone (from 1.53 x 10(5) M(-1)s(-1) at pH = 3.0 and 4.93 x 10(5) M(-1)s(-1) at pH = 6.7) and OH radicals (4.37 x 10(9) M(-1)s(-1) at pH = 5.5 and 4.59 x 10(9) M(-1)s(-1) at pH = 7.5) are also evaluated.     

洁霉素生产废水处理改造工程实例

因企业扩大生产规模和原废水处理工艺设计不合理,出水难于达标。针对废水含高硫酸盐特点,采用预处理-两相厌氧-缺氧/好氧工艺进行处理。稳定运行后,出水达到污水综合排放标准(GB 8978-1996)的二级标准。     

洁霉素废水厌氧生物处理研究

采用上流式厌氧污泥床反应器,在34℃下处理洁霉素废水。通过进水稀释与不稀释的实验对比,分析探讨了有毒有害物质、碱度、容积负荷等对厌氧生物处理的影响。洁霉素废水的CODCr质量浓度为16.8~24.3g/L,BOD5质量浓度为7.2~9.9g/L。在进水不稀释条件下,CODCr负荷为5.7kg/(m3·d),进水CODCr的质量浓度为16.8g/L,进水BOD的质量浓度为7.2g/L时,CODCr平均去除率为72%,BOD5平均去除率为84%。     

磁性金属有机框架材料对水中林可霉素的去除研究

目的 基于磁性金属有机框架材料(metal-organic framework, MOF)的磁固相萃取(magnetic solid phase extraction, MSPE)技术吸附去除环境水样中残留的林可霉素, 有效预防抗生素污染。方法 采用溶剂热法预制Fe3O4纳米颗粒, 然后与铜基金属离子和均苯三甲酸有机配体结合制备Fe3O4-MOF199复合材料。通过扫描电子显微镜(scanning electron microscopy, SEM)、X射线衍射(X-ray diffraction, XRD)、傅里叶红外光谱(Fourier transform infrared spectroscopy, FTIR)、差热热重分析曲线(thermogravimetric differential thermal analysis, TG-DTA)和N2吸附-解吸实验等表征手段对材料的形貌、晶体结构及理化性质进行分析。通过等温吸附平衡和吸附动力学实验评估该材料对林可霉素吸附性能, 并对吸附后洗脱剂进行优化。结果 所制备的Fe3O4-MOF199呈规则的正八面体形态, 并具有较高的比表面积(749.19 m2/g)和优越的热稳定性。吸附实验结果表明该吸附过程符合Freundlich吸附动力学方程和伪二阶动力学模型。Fe3O4-MOF199材料用于海河水和津河水中低浓度的林可霉素吸附, 去除率可达80%以上。结论 Fe3O4-MOF199材料具有良好的吸附性能和吸附效果, 结合MSPE工艺可以有效应用于抗生素残留的吸附, 所建立的方法具有简单、有效、准确的林可霉素吸附去除性能。     

Electrochemical removal of antibiotics from wastewaters

Electro-oxidation tests with different anodes (Ti/Pt, DSA^® type, graphite and three-dimensional (3D) electrode made of a fixed bed of activated carbon pellets) were performed on aqueous solutions containing the antibiotics Ofloxacin and Lincomycin. The effectiveness of the treatment of wastewater containing pharmaceuticals was assessed, as well as the electro-oxidation mechanism.

The use of high electrode potentials (>2.8 V versus NHE) ensured either significant anodic surface activation or minimization of fouling by in situ generated polymeric material. The use of a membrane-divided cell showed positive aspects in terms of molecule demolition, and average power consumption. The electro-oxidation was found to occur with first order kinetics mainly at anode surface when using Na₂SO₄ at low concentration (0.02N). Under these conditions, Ofloxacin is efficiently oxidized over all tested anodes (e.g. 50 mgcm⁻² A⁻¹ h⁻¹ for the bi-dimensional Ti/Pt electrode), whereas Lincomycin is oxidized with slow overall kinetics mainly due to difficult deprotonation, a step that precedes the primary electron transfer stage of the oxidation process. The three-dimensional electrode would be the most appropriate for continuous industrial-scale process. However, at the used potential, unacceptable corrosion of the carbon based electrode was noticed.     

Assessing the depletion of lincomycin in feathers from treated broiler chickens: a comparison with the concentration of its residues in edible tissues

ABSTRACT

Lincomycin is the first antimicrobial agent described for the lincosamide class and it is commonly used for the treatment of infectious enteric and respiratory diseases in poultry. Maximum residue limits (MRLs) in edible tissues have been established for this antimicrobial, however, no regulation has been proposed yet for by-products that are not intended for direct human consumption. Feathers are a by-product from poultry farming that might be used as an ingredient for diets fed to other farm animal species. The presence of antimicrobial residues in them is not monitored in spite of the fact that several studies have proved that they can persist in feathers. Currently though, no evidence has been presented regarding the behaviour of lincomycin in this matrix. Hence, this work intended to assess the depletion of lincomycin residues in feathers of birds treated with therapeutic doses and compare them with those detected in muscle and liver samples. Samples were collected for several days after ceasing treatment from a group of broiler chickens treated with a 25% lincomycin formulation. Methanol and Florisil® columns were used to extract and retain the analyte, and samples were analysed using a triple quadrupole mass spectrometer (API 5500, AB SCIEX?). On day 1 after ceasing treatment, average concentrations of lincomycin detected in feather samples reached up to 8582 μg kg^?1 and by day 16, these had only declined by 63%, to an average of 3138 μg kg^?1. Lincomycin residues were detected in feathers at every sampling point, even after they were not detectable in edible tissues. Depletion time was 98 days for feathers, considering the LOQ established for the methodology as cut-off value for the calculations. Data showed that lincomycin is highly persistent in feathers, which may result in this matrix becoming a re-entry route for its residues into the food chain.     

Quantitative analysis of lincomycin and narasin in poultry, milk and eggs by liquid chromatography-tandem mass spectrometry

This study presents the simultaneous extraction and determination of lincomycin (LCM) and narasin (NAR) by using liquid chromatography-electrospray ionisation tandem mass spectrometry (LC-MS/MS) on samples from poultry, milk and eggs (n = 196). The homogenised samples are extracted with acetonitrile and the extract is further cleaned using C₁₈ solid-phase extraction cartridges. The recoveries of the analytes in different matrices were found ranging from 90% to 101% and 85% to 95% for LCM and NAR, respectively. The corresponding limits of detection were 0.6 and 1.5 ng g⁻¹ for LCM and NAR, respectively. As a result of monitoring, NAR was not detected in any samples and LCM was detected in one egg with a concentration of 25 ng g⁻¹. The method was relatively simple to perform and therefore could be used for food safety surveillance activities.