共查询到19条相似文献,搜索用时 171 毫秒
1.
目前,聚氨酯(PUR)塑料占据全球塑料市场的6%左右,然而,由于处置不合理,大量聚氨酯塑料被丢弃到环境当中,造成了严重的资源浪费和环境污染等问题。废弃塑料的资源再利用已成为各个国家关注的重要问题。废弃塑料处理主要包括掩埋、焚烧以及机械回收、物理化学和生物利用等。与传统物理和化学法的降级利用相比,生物法因其绿色安全和潜在的高值化利用而成为研究者关注的热点。然而,塑料高分子特殊的分子结构使得目前塑料生物处理依然存在诸多问题,难以实现规模化应用。本文综述了PUR的化学结构和PUR降解性微生物的筛选方法,并总结了PUR降解微生物和降解酶的研究现状以及评价其降解效果的方法,为推进PUR生物降解研究提供了一定参考。 相似文献
2.
聚氨酯(polyurethane,PUR)塑料因其特殊的理化性质而被广泛应用。然而,大量废弃PUR塑料的不合理处置造成了严重的资源浪费和环境污染。利用微生物的手段实现废弃PUR塑料的高效降解和循环利用成为目前的研究热点之一,而高效降解菌是PUR塑料生物法处理的关键。本研究以垃圾填埋场PUR类废塑料样品为来源,分离到一株能够降解PUR类似物Impranil DLN的微生物,并对其PUR降解特性开展了研究。通过16S rRNA基因序列比对将该菌初步鉴定为拟无枝杆菌属(Amycolatopsis sp.),命名为G-11。PUR塑料降解实验结果表明,菌株G-11对商业化PUR塑料的减重率达到4.67%,扫描电镜(scanning electron microscope,SEM)发现塑料结构被破坏,表面出现侵蚀。接触角分析和热重分析(thermogravimetric analysis,TGA)结果发现,菌株G-11处理后的PUR塑料的亲水性增强,热稳定性下降,该结果与减重和扫描电镜结果相一致。结果表明,分离自垃圾填埋场的菌株G-11在废弃PUR类塑料生物降解方面具有一定的应用潜力。 相似文献
3.
合成塑料已广泛应用于国民经济各领域,是国民经济的支柱产业。然而,不规范生产、使用塑料制品以及处置塑料废弃物等问题,造成塑料在环境中长期累积,导致了严重的环境污染和碳资源浪费。生物降解是实现废塑料污染治理与资源化的新途径,已成为国内外废弃塑料处置研究的热点。近年来,在塑料降解微生物/酶资源的分离、筛选、鉴定以及对其进行工程化改造等方面取得了重要突破,为环境中微塑料的治理、废塑料的闭环循环再生提供了新的思路和方案。另一方面,利用微生物(纯菌或菌群)将塑料降解产生的单体进一步转化为生物可降解塑料及其他具有高附加值的化合物,对于解决废塑料的生态环境污染、推动塑料循环经济发展以及减少塑料在生命周期中的碳排放等方面具有重要意义。《生物工程学报》特组织出版“塑料的生物降解与转化”专刊,邀请了国内外塑料生物降解与转化领域的相关专家学者介绍了塑料生物降解资源的发掘、塑料解聚酶的设计与改造、塑料降解物的生物高值转化等领域最新进展和研究成果,收录了包括评论、综述、研究论文等类型的相关文章16篇,为塑料生物降解与转化的进一步研究提供借鉴和指导。 相似文献
4.
随着全球塑料循环体系的变革升级,提高塑料的回收利用不仅可以减少塑料在生命周期中的碳排放,还可以解决废塑料潜在的生态环境危害。文中介绍了2019年国家自然科学基金组织间国际 (地区) 合作研究项目“废塑料资源高效生物降解转化的关键科学问题与技术 (MIXed plastics biodegradation and UPcycling using microbial communities,MIX-UP)”。该项目聚焦“塑料污染”这一全球化的问题,围绕中欧双方确定的“塑料生物降解菌群”研究领域,联合中欧双方14家优势科研单位,开展实质性的重大前沿合作研究。针对废塑料生物降解中存在的解聚与重塑两个难题,项目以难降解石油基塑料 (PP、PE、PUR、PET和PS) 以及生物可降解塑料 (PLA和PHA) 的混合废塑料作为研究对象,从塑料微生物降解途径解析及关键元件的挖掘与改造、塑料高效降解混菌/多酶体系的构建与功能调控、塑料降解物的高值化炼制途径设计与利用策略3个方面展开研究。本项目将突破废塑料生物降解转化中高效降解元件挖掘、塑料降解物高值化利用的关键科学问题与技术,探索一条废塑料资源化、高值化、循环化、低碳化的新塑料循环路线,建立以“降塑再造”为核心理念的废塑料生物炼制体系,丰富我国固废资源化生物技术利用平台。项目的实施不仅有助于提升我国塑料 (生物) 循环经济的理论基础和关键技术水平,还可以推动我国与国际科研院所的多边交流与合作,促进我国在生物技术领域的创新发展,助力我国碳中和目标的实现。 相似文献
5.
聚乙烯塑料的微生物降解 总被引:1,自引:0,他引:1
聚乙烯(polyethylene,PE)是产量最大的通用塑料之一,通常被加工成一次性包装材料(包括塑料袋及容器)和农用薄膜等。PE塑料的广泛应用导致大量PE废弃物的累积,对生态环境造成严重的威胁。自20世纪70年代以来,一些研究陆续报道了PE塑料被微生物降解的现象,并从土壤、海洋、垃圾堆置点及昆虫肠道等生境中分离筛选到了若干种具有一定PE塑料降解能力的菌株,而且发现一些单加氧酶、过氧化物酶和漆酶等氧化还原酶对PE塑料具有氧化降解能力。这些研究为发展PE塑料废弃物生物降解处理技术提供了一定的依据。本文总结和分析了PE塑料降解微生物的分离和筛选方法,以及已报道的PE塑料降解微生物和降解酶的研究进展,以期为进一步研究PE塑料的微生物降解机理和处理技术提供参考。 相似文献
6.
当前社会塑料制品的使用需求持续增加,塑料垃圾处理压力不断增大,减缓塑料污染成为当务之急,生物可降解塑料因可在一定生物活性环境下较快降解而备受关注,具有广阔的应用前景。生物可降解塑料降解条件复杂,影响因素众多,对不同生物可降解塑料降解规律,降解微生物和功能酶的透彻掌握,是实现其全面利用和高效资源化处理处置的基础和前提。文章系统梳理了常见生物可降解塑料的种类、性能、优缺点和主要用途,全面综述了生物可降解塑料的降解机理、降解微生物和功能酶,以及生物可降解塑料在不同环境条件下的降解周期和程度,以期为生物可降解塑料的微生物降解研究提供借鉴,为生物可降解塑料废弃物的高效处理处置和彻底降解提供科学参考。 相似文献
7.
聚氨酯(polyurethane,PUR)塑料在日常生活中发挥着重要作用,但同时PUR废弃物也带来严重的环境污染问题。生物(酶)降解是一种环境友好、成本低廉的PUR废弃物回收方法,其关键在于获得高效的降解菌株或酶。本研究从垃圾填埋场的聚氨酯废弃物表面分离出了一株聚酯型PUR降解菌株YX8-1。基于菌落和显微形态观察、16S rDNA和DNA旋转酶(DNA gyrase)基因gyrA系统发育分析及基因组序列比对,将该菌鉴定为高地芽孢杆菌(Bacillus altitudinis)。高效液相色谱(high performance liquid chromatography,HPLC)及液相色谱-质谱联用(liquid chromatography-tandem mass spectrometry,LC-MS/MS)结果显示菌株YX8-1能降解自行合成的聚酯型PUR寡聚物(PBA-PU),并产生单体化合物4,4′-亚甲基二苯胺。此外,菌株YX8-1能在30 d内使商品化的聚酯型PUR海绵失重32%。本研究为PUR废弃物的生物降解提供了菌株资源,也为挖掘相关降解酶打下了基础。 相似文献
8.
伴随着环境污染的日益严重,处理"白色污染"成为人们面临的一个棘手难题,而各种合成塑料因为应用广泛且很难降解成为其"主要元凶"。利用自然界存在的或者是进化产生的微生物可降解合成塑料是一种环境友好型的策略。以国家自然科学基金国际(地区)合作和交流(中欧组织间合作研究NSFC-EU)项目"合成塑料降解转化微生物菌群"为基础,总结近年来筛选到的能够降解合成塑料,如聚乙烯(Polyethylene,PE)、聚丙烯(Polypropylene,PP)、聚苯乙烯(Polystyrene,PS)、聚氯乙烯(Polyvinyl chloride,PVC)、聚氨酯(Polyurethane,PUR)、聚对苯二甲酸乙二醇酯(Polyethylene terephthalate,PET)的纯细菌、纯真菌及微生物菌群的研究状况,分析了各种微生物在石油基塑料降解中的作用,讨论了微生物及其降解酶对合成塑料降解研究的优缺点。 相似文献
9.
双酚A型聚碳酸酯(bisphenol-A polycarbonate, PC)是一种应用广泛的热塑性工程塑料,常用于医用材料和电子设备等产品。PC塑料废弃物在环境中的大量累积对生态系统和人类健康带来危害。微生物降解被认为是一种可持续发展的PC废弃物资源回收利用技术。本文综述了目前PC塑料降解的国内外研究成果,包括PC塑料的污染现状及其生物和非生物的降解,特别对PC塑料的降解微生物和降解酶研究进行了详细的总结,并在这些研究成果的基础上,提出了PC塑料降解可能的线路化设计,为潜在的PC塑料废弃物的循环利用和高值化应用提供一定的借鉴。 相似文献
10.
石油基塑料种类繁多、数量巨大、应用广泛,常见的有聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS)、聚氯乙烯(PVC)、聚对苯二甲酸乙二醇酯(PET)、聚氨酯(PUR)等。这些合成塑料因其高分子量、高疏水性及高化学键能的特点难以被微生物降解,从而在环境中长期存在和累积,"白色污染"已经成为一个全球性问题。因此安全经济的微生物降解合成塑料是人类面临的一个选择和难题。文中从微生物资源及相关酶学研究方面综述了聚苯乙烯、聚乙烯、聚丙烯、聚氨酯、聚对苯二甲酸乙二醇酯和聚氯乙烯这6种石油基塑料的生物降解的研究现状。目前关于上述6种石油基塑料的微生物降解研究依然大多停留在微生物资源的寻找中,已发现的具备相关能力的菌株种类较少,并且微生物降解效率均非常缓慢;对于其降解机理及关键基因和酶的研究比较少。文中为进一步开展塑料生物降解研究,寻找高效的塑料降解菌株资源以及进一步在遗传、分子和生化水平研究塑料生物降解机理研究,从而最终实现合成塑料的彻底降解和高值化利用提供了借鉴。 相似文献
11.
12.
利用微生物对聚氨酯 (Polyurethane,PUR) 类污染物进行生物降解是目前的研究热点之一。寻找能高效降解聚氨酯的微生物是该类研究的重要前提。文中从塑料垃圾填埋场中分离培养了1株PUR高效降解菌株P10。基于菌落形态观察和16S rDNA系统发育分析,鉴定其为短芽孢杆菌属Brevibacillus的细菌。通过PUR的模式底物水性聚氨酯 (Impranil DLN) 比浊法,确定了该菌株能在6 d内降解71.4%的Impranil DLN。此外,菌株P10能够利用商业聚氨酯海绵作为唯一碳源进行生长;通过降解条件的优化,在5% (V/V) LB作为额外碳源的辅助下实现了6 d内对50 mg PUR泡沫的降解。以上结果表明Brevibacillus sp. P10在聚氨酯废弃物的生物降解过程中具有一定的应用潜力。 相似文献
13.
14.
Biodegradation of Polyester Polyurethane by Endophytic Fungi 总被引:1,自引:0,他引:1
Jonathan R. Russell Jeffrey Huang Pria Anand Kaury Kucera Amanda G. Sandoval Kathleen W. Dantzler DaShawn Hickman Justin Jee Farrah M. Kimovec David Koppstein Daniel H. Marks Paul A. Mittermiller Salvador Joel Nú?ez Marina Santiago Maria A. Townes Michael Vishnevetsky Neely E. Williams Mario Percy Nú?ez Vargas Lori-Ann Boulanger Carol Bascom-Slack Scott A. Strobel 《Applied and environmental microbiology》2011,77(17):6076-6084
Bioremediation is an important approach to waste reduction that relies on biological processes to break down a variety of pollutants. This is made possible by the vast metabolic diversity of the microbial world. To explore this diversity for the breakdown of plastic, we screened several dozen endophytic fungi for their ability to degrade the synthetic polymer polyester polyurethane (PUR). Several organisms demonstrated the ability to efficiently degrade PUR in both solid and liquid suspensions. Particularly robust activity was observed among several isolates in the genus Pestalotiopsis, although it was not a universal feature of this genus. Two Pestalotiopsis microspora isolates were uniquely able to grow on PUR as the sole carbon source under both aerobic and anaerobic conditions. Molecular characterization of this activity suggests that a serine hydrolase is responsible for degradation of PUR. The broad distribution of activity observed and the unprecedented case of anaerobic growth using PUR as the sole carbon source suggest that endophytes are a promising source of biodiversity from which to screen for metabolic properties useful for bioremediation. 相似文献
15.
Microbial degradation of polyurethane, polyester polyurethanes and polyether polyurethanes 总被引:9,自引:0,他引:9
Nakajima-Kambe T Shigeno-Akutsu Y Nomura N Onuma F Nakahara T 《Applied microbiology and biotechnology》1999,51(2):134-140
Polyurethane (PUR) is a polymer derived from the condensation of polyisocyanate and polyol and it is widely used as a base
material in various industries. PUR, in particular, polyester PUR, is known to be vulnerable to microbial attack. Recently,
environmental pollution by plastic wastes has become a serious issue and polyester PUR had attracted attention because of
its biodegradability. There are many reports on the degradation of polyester PUR by microorganisms, especially by fungi. Microbial
degradation of polyester PUR is thought to be mainly due to the hydrolysis of ester bonds by esterases. Recently, polyester-PUR-degrading
enzymes have been purified and their characteristics reported. Among them, a solid-polyester-PUR-degrading enzyme (PUR esterase)
derived from Comamonas acidovorans TB-35 had unique characteristics. This enzyme has a hydrophobic PUR-surface-binding domain and a catalytic domain, and the
surface-binding domain was considered as being essential for PUR degradation. This hydrophobic surface-binding domain is also
observed in other solid-polyester-degrading enzymes such as poly(hydroxyalkanoate) (PHA) depolymerases. There was no significant
homology between the amino acid sequence of PUR esterase and that of PHA depolymerases, except in the hydrophobic surface-binding
region. Thus, PUR esterase and PHA depolymerase are probably different in terms of their evolutionary origin and it is possible
that PUR esterases come to be classified as a new solid-polyester-degrading enzyme family.
Received: 20 July 1998 / Received revision: 9 October 1998 / Accepted: 11 October 1998 相似文献
16.
塑料广泛存在于人类的日常生活中,在给人们生活带来便利的同时,大量塑料废物也给环境带来很大压力。聚对苯二甲酸乙二醇酯(polyethylene terephthalate, PET)是一种以石油为原料的高分子热塑性材料,因其具有耐用、透明度高、重量轻等特性,已成为世界上使用最广泛的塑料之一。由于PET具有结构复杂以及难降解的特性,可在自然界中长期存在,不仅对全球生态环境造成严重的污染,而且已经威胁到人类健康。如何对PET废弃物进行降解已成为全球的难题之一,相较于物理法和化学法,生物降解法是目前处理PET废弃物最为绿色环保的方法。本文分别介绍了微生物和生物酶对PET生物降解的研究现状、PET的生物降解途径、PET生物降解机制以及PET降解酶的分子改造等方面的研究,并对如何实现PET的高效降解、寻找和改造可降解高结晶度PET的微生物或酶进行展望,为PET的生物降解微生物或酶的有效开发应用提供理论依据。 相似文献
17.
Anming Xu Jiawei Liu Shixiang Cao Bin Xu Chengzhi Guo Ziyi Yu Xiaoqiang Chen Jie Zhou Weiliang Dong Min Jiang 《Microbial biotechnology》2023,16(2):474-480
Application of polyester-degrading microorganisms or enzymes should be considered as an eco-friendly alternative to chemical recycling due to the huge plastic waste disposal nowadays. However, current impranil DLN-based screening of polyester-degrading microorganisms is time-consuming, labour-intensive and unable to distinguish polyesterases from other protease- or amidase-like enzymes. Herein, we present an approach that combined a novel synthetic fluorescent polyurethane analogue probe (FPAP), along with the droplet-based microfluidics to screen polyurethane-degrading microorganisms through fluorescence-activated droplet sorting (FADS) pipeline. The fluorescent probe FPAP exhibited a fluorescence enhancement effect once hydrolysed by polyesterases, along with a strong specificity in discriminating polyesterases from other non-active enzymes. Application of FPAP in a microfluidic droplet system demonstrated that this probe exhibited high sensitivity and efficiency in selecting positive droplets containing leaf-branch compost cutinase (LCC) enzymes. This novel fluorogenic probe, FPAP, combined with the droplet microfluidic system has the potential to be used in the exploitation of novel PUR-biocatalysts for biotechnological and environmental applications. 相似文献
18.
Biodegradation of plastics 总被引:16,自引:0,他引:16
Shimao M 《Current opinion in biotechnology》2001,12(3):242-247
Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes. 相似文献
19.
José Maria Rodrigues da Luz Sirlaine Albino Paes Mateus Dias Nunes Marliane de Cássia Soares da Silva Maria Catarina Megumi Kasuya 《PloS one》2013,8(8)
Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate. 相似文献