光催化降解对抗生素藻类毒性效应影响研究进展

抗生素滥用带来环境中残留抗生素及其抗性基因的问题,近年来已成为全球关注的热点问题.光催化氧化技术是当前研究领域广泛采用的有效降解水环境中残留抗生素的热门方法;但光催化氧化无法使水环境中抗生素完全矿化,存在生态风险,探明光催化降解抗生素对其藻类毒理效应影响及内在机制,对研发高效、安全的光催化技术具有重要意义.本文在总结水环境中残留抗生素的藻类毒性检测方法和毒性效应的基础上,分析了光催化降解对抗生素藻类毒性效应的影响及其内在机制,并总结了不同抗生素的光催化反应及降解产物,讨论了两者与藻类毒性效应之间可能存在的关系,旨在为实现高效、安全光催化技术的可控设计提供思路.     

环境中抗生素及其生态毒性效应研究进展

近年来,越来越多的抗生素类药物用于在医疗、畜禽和水产养殖业。由于其机体代谢率低,大部分以原药或代谢物的形式经由尿液和粪便排出体外进入环境中,造成抗生素在水体和土壤等环境介质中的残留。这些残留的抗生素会导致潜在的环境风险,其中最严重的是会诱发和传播各类抗生素抗性基因(antibiotic resistance genes,ARGs),进而对人类健康产生威胁。本文介绍了环境中抗生素的来源,归趋和残留状况,并且对其所引起的生态毒性效应以及ARGs进行总结,最后指出了目前研究中存在的问题,并对未来研究进行了展望。     

抗生素对微生物的联合与低剂量毒性研究进展

目前抗生素已成为一类不可忽视的环境污染物,它在环境中呈"混合-持久-低剂量"的暴露特征。因此,研究抗生素毒性效应,特别是它的联合毒性以及低剂量下毒性兴奋效应,对抗生素污染物生态风险的评价极其重要。以抗生素联合毒性的研究进展为主线,重点概述了抗生素二元混合物的急性和慢性联合毒性研究,指出了抗生素混合物间存在相互作用,它们的联合毒性并非表现为简单的加和或独立效应,且抗生素急性-慢性联合表现出的毒性效应也存在差异;发现了不仅单一抗生素具有Hormesis效应,低剂量抗生素二元混合物也具有Hormesis作用。但目前低剂量抗生素二元混合物对微生物的毒性兴奋效应研究较少,其毒性兴奋效应的预测和评价还有待进一步完善,以期为环境中抗生素的联合生态研究和风险评价提供理论依据。     

抗生素环境行为及其环境效应研究进展

抗生素作为一类抗菌性药物广泛用于预防和治疗人类和动物疾病,并且在畜牧和水产养殖业中用于促进动物的生长.进入人和动物体内的抗生素不能被生物体完全吸收,大部分以原药或代谢物的形式经由尿液和粪便排出体外进入环境中.抗生素是环境中一类新型污染物,由于其使用量大和诱导产生抗生素耐药菌株,对人类健康和生态环境构成威胁,近年来受到日益广泛的关注.抗生素诱导产生的抗性基因(ARGs)也已经被定义为环境中一类新型污染物.本文介绍了抗生素的使用现状、环境来源以及不同环境介质中抗生素的分析方法和污染现状,并且对其吸附降解行为、毒性效应以及ARGs进行了讨论,最后指出了目前研究中存在的问题,并对未来研究进行了展望.在今后,应该更加系统地研究环境中抗生素的污染现状及其迁移转化等行为;开展低剂量长期慢性毒性和复合毒性效应研究;加强对环境中ARGs的污染现状和环境行为研究.     

兽用抗生素在土壤环境中的行为及其生态毒理效应研究进展

目前全球至少有70%左右的抗生素被用于畜牧业和水产养殖业,这些抗生素大多不能被动物完全吸收,以母体或代谢物的形式排出动物体外的抗生素约占用药量的40～90%,排出体外的抗生素大多随粪便等进入环境尤其是土壤环境中并在其中累积.为了明确兽用抗生素对环境中生物等的影响,合理评价兽用抗生素的环境风险,论文就土壤环境中兽用抗生素的来源,兽用抗生素在土壤环境中的吸附、迁移、降解以及对环境中生物的影响等方面进行了综述,在此基础上提出了今后的重点研究方向.     

典型抗生素与群体感应抑制剂对费氏弧菌的三元慢性联合毒性

群体感应抑制剂(quorum sensing inhibitor,QSIs)广泛应用之后与环境中现有抗菌药物共存的趋势不可避免。为了评价QSIs和现有抗菌药物共存所引起的生态环境效应,本文以费氏弧菌(Vibrio fischeri)作为模式生物,磺胺类抗生素磺胺氯哒嗪(SCP)、磺胺类增效剂甲氧苄嘧啶(TMP)和群体感应抑制剂4-溴-5-溴亚甲基-2(5氢)-呋喃酮(FC-30)为研究对象,测定了以上3个化合物对Vibrio fischeri的单一/混合慢性毒性效应。单一慢性毒性结果表明,3个化合物的毒性大小如下:FC-30SCPTMP,混合慢性毒性结果表明三元混合体系联合效应为拮抗。进一步分析可知,SCP+FC-30和TMP+FC-30两个混合体系的拮抗作用是三元混合体系为拮抗效应的根本原因。最后指出,因为SCP、TMP和FC-30的三元混合体系是拮抗作用,所以从环境生态风险角度分析,三者联合用药对环境的影响小于单一用药。     

典型环境污染物对肠道菌群的影响及机制研究进展

随着环境污染日益严重,国内外有关环境污染物导致健康风险的毒性机制研究已引起广泛关注.然而,环境污染物对机体肠道菌群结构、功能的改变及其对毒性效应的调控作用研究尚处起步阶段.本综述在归纳近年来国内外人体及模式生物的肠道菌群研究进展的基础上,重点阐述了以重金属污染物、微纳米颗粒污染物、持久性有机污染物以及抗生素为代表的典型环境污染物对肠道菌群结构、组成、数量以及代谢等的影响,总结了肠道菌群在机体毒性效应中潜在调控作用,为后续肠道菌群在环境污染物毒理学效应及人类健康风险方面的系统研究提供理论参考.     

微塑料污染现状及其毒性效应和机制研究进展

微塑料(microplastics,MPs)作为一种新型的环境污染物近年来逐渐引起全世界的关注,除了对生态环境的影响,微塑料对生物体的毒性效应及其潜在的健康风险也日益成为环境领域的研究热点.本文基于已有研究,阐述微塑料的污染现况,总结微塑料进入机体的分布,归纳微塑料的生物毒性作用和机制,分析微塑料毒性效应的影响因素,并展望了未来的研究方向,为进一步开展微塑料的生物毒性效应、机制研究和健康风险评估提供科学线索和参考.     

水产品中多氯联苯代谢产物的研究进展

多氯联苯是斯德哥尔摩公约首批禁止的持久性有机污染物之一.残留在环境中的多氯联苯,由于其亲脂特性可在生物体内进行生物积累以及在食物链中产生生物放大效应,并在肝脏中代谢产生羟基多氯联苯、甲磺基多氯联苯、多氯联苯硫酸盐等.代谢产物在水生生物体内会产生与内分泌相关的毒性作用,继而导致的水产品质量安全问题,引起了国际范围的持续关注.本文从多氯联苯代谢产物的定性定量分析方法、毒性效应及机理、多氯联苯生物转化机制等方面展开综述,并对目前全球范围内关于水产品中多氯联苯代谢产物同系物类型、残留水平以及对其影响水产品质量安全的研究进展进行了全面的总结概述.     

中药抗菌剂对费氏弧菌的单一及联合毒性效应

抗生素滥用所导致的环境问题日益受到人们的关注,寻找传统抗生素的可能替代品迫在眉睫.从中药中提取的具有抗菌活性的化合物(简称中药抗菌剂)因具有资源丰富、抗菌谱广和不良反应低等特点,有望成为未来替代抗生素的关键.因此,有必要探究中药抗菌剂的毒性效应,这可以对未来中药抗菌剂使用后的生态风险提供指导.本文以费氏弧菌作为模式生物,分别测定了大黄素(emodin,EMO)、大黄酸(rhein,RH)、芦荟大黄素(aloe-emodin,AE)和双氢青蒿素(dihydroartemisinin,DHA)4种中药抗菌剂对费氏弧菌的单一和多元联合毒性,同时进行了抑菌作用机理的初步讨论.结果 表明,4种中药抗菌剂对费氏弧菌的生物荧光均能产生较为明显的抑制作用,毒性排序是EMO＞RH＞AE＞DHA.而当EMO、RH、AE和DHA混合暴露时,混合物在高浓度区间的联合毒性作用模式均为拮抗,推测是受试中药抗菌剂之间互相竞争性地对NADH脱氢酶产生抑制作用,从而导致对发光反应的抑制作用较单一暴露时减弱.本研究对未来中药抗菌剂单一及联合毒性效应的研究具有积极的推动作用,有望为今后中药抗菌剂的生态风险评价提供参考.     

Tetracycline antibiotics in the environment: a review

Tetracycline antibiotics are one of the primarily antibiotics groups used for veterinary purposes, for human therapy and for agricultural purposes. Amongst the different antibiotics used, more attention is paid to tetracycline’s as it exhibits serious environmental problems including ecological risks and human health damages. Due to their extensive usage, most of the actual evidence suggests that tetracycline antibiotics are omnipresent compounds found in different ecological compartments. After medication, more than 70 % of tetracycline antibiotics are excreted and released in active form into the environment via urine and feces from humans and animals. Their highly hydrophilic character and low volatility have resulted in significant persistence in the aquatic environment. Very few studies describe the fate and toxicity of tetracycline antibiotics in the environment. Here, we review several important issues with regard to: (1) the toxicity of these compounds on aquatic and terrestrial organisms; (2) their estrogenic effects; (3) their behavior in different ecological systems and; (4) the by-products generated during water treatment. These antibiotics residues promote the development of antibiotic resistant microorganisms, which can induce adverse effect to human health by increasing the risk of certain infections. Based on recent research results, the occurrence of tetracycline antibiotics in the environment inhibits the growth of some terrestrial and aquatic species. Besides, the residual concentrations of such drugs could affect steroidogenic pathway and consequently may cause endocrine disruption of aquatic species. Most of the wastewater treatment plants are not capable of removing effectively the tetracycline antibiotics. Therefore, there is a need to develop alternative processes to remove them from waters. Advanced oxidation processes have been proposed as alternative methods to ensure higher degradation and mineralization of tetracycline antibiotics are present in waters.     

土壤中抗生素的生态毒性及其分子生物标志物技术的研究进展

抗生素作为抑菌或杀菌药物被广泛应用于畜禽养殖中。不能完全被机体吸收的抗生素经由畜禽排泄物直接进入环境。随着耐药基因和超级病菌的出现,抗生素产生的环境问题引起了广泛关注。土壤是环境中抗生素最主要的累积场所之一,对土壤中抗生素的生态毒性及其分子生物指示指标的研究具有重要意义。本文在总结国内外相关研究的基础上,阐述了抗生素对土壤中微生物、动物和植物所产生的毒性以及分子生物标志物在土壤抗生素污染研究中的应用,并对未来的研究工作进行了展望。     

抗生素的环境残留、生态毒性及抗性基因污染

抗生素的环境污染与生态毒害问题近年来引起了极大的关注.在总结国内外相关研究基础上,对环境中几种典型抗生素(四环素、土霉素、氯四环素和磺胺类等)的污染源以及在水和土壤环境中的残留与污染水平进行了分析;对抗生素的污染生态毒性最新研究进展给予了评述;对抗生素抗性基因在环境中可能的暴露途径进行了探讨,指出应将抗生素抗性基因作为一类新的环境污染物.鉴于我国抗生素污染的严峻事实,建议应从国家层面上尽快开展有关抗生素环境污染和生态毒害机理的系统研究.     

Antibiotika als Umweltkontaminanten — Effekte auf Bodenbakterien

Goal and scope

Among the human and veterinary pharmaceuticals, antibiotics form an important group. Recent research addressed the environmental ‘side effects’ of antibiotics. Evidence for environmental effects of antibiotics has for example been found for the respiratory activity of soil microorganisms. In the present contribution, results of studies on the ecotoxicology of antibiotics that are based on the utilization of carbon substrates in so-called Biolog plates are summarized.

Methods, Results and Conclusions

The method of pollution-induced community tolerance (PICT) takes centre stage. PICT is based on the changes in community composition of environmental communities brought about by a toxicant, which lead to an overall increase in community tolerance to this toxicant. The suitability of such an increase in community tolerance as ecotoxicological endpoint had been the subject of several experiments. It was shown that effect testing of antibiotics requires supplementation of the communities with nutrients, and that the PICT method reveals antibiotic effects with a high specificity. In an application of PICT, effects of three classes of antibacterial compounds were investigated. Dose-response relationships were obtained for all substances, and effect concentrations were partly in the range of expected environmental concentrations. The possible risks of antibiotic use for an increase in the occurrence of antibiotic resistance genes in the environment are also touched upon, including the extent of natural resistance.

Outlook

Due to its specificity, the PICT method has shown to be a suitable ecotoxicological assay. Due to possible effects of tetracyclines on the structure of the soil microbial community, it is advised to use veterinary antibiotics with caution. The risks of an increase in the occurrence of antibiotic resistance in the environment should be investigated in more detail.     

纳米银在水环境中的环境行为和毒性效应研究进展

纳米材料的环境行为和生态效应是目前国内外研究的热点,其中纳米银颗粒(Ag NPs)是使用量最高的纳米材料。本文主要总结了Ag NPs在水环境中的赋存、Ag NPs的环境行为、Ag NPs对不同种类微生物的毒性效应以及影响Ag NPs毒性效应的因素,最后对Ag NPs在河口区的研究进行了展望。     

Culturomics and metagenomics: In understanding of environmental resistome

State of the art of culturomics and metagenomics to study resistome was presented. The combination of culturomics and metagenomics approaches was proposed. The research directions of antibiotic resistance study has been suggested. Pharmaceutical residues, mainly antibiotics, have been called “emerging contaminants” in the environment because of their increasing frequency of detection in aquatic and terrestrial systems and their sublethal ecological effects. Most of them are undiscovered. Both human and veterinary pharmaceuticals, including antibiotics, are introduced into the environment via many different routes, including discharges from municipal wastewater treatment plants and land application of animal manure and biosolids to fertilize croplands. To gain a comprehensive understanding of the widespread problem of antibiotic resistance, modern and scientific approaches have been developed to gain knowledge of the entire antibiotic-resistant microbiota of various ecosystems, which is called the resistome. In this review, two omics methods, i.e. culturomics, a new approach, and metagenomics, used to study antibiotic resistance in environmental samples, are described. Moreover, we discuss how both omics methods have become core scientific tools to characterize microbiomes or resistomes, study natural communities and discover new microbes and new antibiotic resistance genes from environments. The combination of the method for get better outcome of both culturomics and metagenomics will significantly advance our understanding of the role of microbes and their specific properties in the environment.     

畜禽养殖过程抗生素使用与耐药病原菌及其抗性基因赋存的研究进展

兽用抗生素在提高畜禽生产性能、防治疾病方面发挥着重要作用,目前全球超过一半以上抗生素用于畜禽养殖,畜禽养殖源耐药病原菌、抗性基因及其传播风险愈益得到人们的重视。我国是畜禽养殖和抗生素使用大国,但兽用抗生素使用、病原菌耐药水平及其抗性基因类型等数据却较为缺乏,不利于今后畜禽养殖源耐药病原菌及其传播风险的控制。因此,本文通过文献调研,对我国和主要发达国家的兽用抗生素使用情况、畜禽养殖源耐药病原菌及其携带的抗性基因、基因移动元件以及向环境传播的途径进行分析、总结,以期为规范合理用药、降低耐药病原菌及其抗性基因传播风险,建立从畜禽养殖场至公共环境全过程的抗性污染控制链条提供借鉴。