微生物降解有机污染物的研究进展

从降解菌的筛选及检测技术、新的降解菌种及其作用酶和代谢途径、污染物对降解菌的作用以及环境因素对降解菌的影响等方面介绍了微生物降有毒有机污染物的最新研究进展,预期该领域具有十分广阔的应用前景。     

植物-微生物联合对环境有机污染物降解的研究进展

环境中有机污染物的过量积累对生态系统及人类健康造成严重威胁。近年来,许多学者研究发现植物-微生物联合作用对环境中有机污染物的去除及生态系统的修复具有非常显著的效果。本文主要从植物-内生菌、植物-菌根菌以及植物-根际微生物这三个层面详细阐述植物-微生物联合降解有机污染物的研究现状,分析植物-微生物在联合降解中的作用,揭示植物-微生物联合降解的机理。但就目前而言,植物-微生物联合降解有机污染物仍存在许多问题,植物-微生物联合降解有机污染物的机理及生态学效应仍不清楚。因此,还需要进一步探讨其潜在作用机制并加强应用实践,这将有助于污染生态系统的治理,促进环境可持续发展。     

降解强致癌性有机污染物的微生物

多氯联苯(PCB)是强致癌有机污染物之一,是潜在的致癌因子,这类化合物有209种之多,其中某些化合物具有类似二噁英(dioxin)的毒性如六氯联苯等。有些微生物对PCB有降解作用,如G^ 细菌(指革氏阳性菌)中有园红球菌(Rhodococcus globerulus)也称球状红球菌,还有红串红球菌(Rh．erythropolis)、芽孢杆菌(Bacillus sp．)野生株以及该两属其他未定名菌株均表现对PCB等的降解活力,     

微生物降解持久性有机污染物的研究进展与展望

持久性有机污染物（POPs）是伴随着人类工业化发展而产生的合成类污染物,具有高毒性、持久性、长迁移性和高生物富集性等特点,POPs污染物的微生物降解一直是环境科学与技术应用领域的研究热点。微生物降解技术修复POPs污染环境具有无二次污染、成本低、快速简便等优点,拥有广泛的应用前景。本文论述了各种POPs微生物分解代谢的最新研究进展,包括降解性微生物资源以及降解机制。此外,还讨论了计算生物学、合成生物学、基因组学等技术在POPs微生物降解中的潜力和应用,以期为环境中持久性有机污染物的修复提供参考。     

微生物治理有机污染物

这些年来,微生物科学工作对利用微生物治理环境中有害、有毒有机污染物的研究取得重要进展。利用微生物对各类不同的有机污染物进行降解和转化有着巨大潜力,这同微生物所具备的几方面的特点密切相关：(1)个体微小,比表面积大．代谢速度快;(2)种类繁多(含未培养的微生物),分布广(含地球以外的生命体),代谢类型多样;(3)繁殖快、易变异、适应性强(含各类嗜极微生物);     

微生物菌剂在难降解有机污染治理的研究进展

大量的难降解有机污染物被排放到环境中,因其蓄积性、持久性和生物毒性,对人类健康和生态环境造成严重危害。近年来,利用微生物菌剂治理难降解有机污染物的研究已取得较好的进展。综述微生物菌剂在国内外的发展历程,介绍微生物菌剂制备中常用的固定化技术及载体材料,并分析总结微生物菌剂在酚类物质、多环芳烃和多氯联苯等有机污染物治理中的研究进展。在此基础上,提出治理难降解有机污染物的微生物菌剂研发所存在的主要问题及其展望。     

硝酸盐还原促进毒害性有机污染物降解的研究进展

大量具有高毒性、持久性和生物蓄积性的有机污染物被排放到环境中,对生态环境和人类健康造成了严重威胁。近年来,利用硝酸盐作电子受体在厌氧条件下降解毒害性有机污染物,已取得一定的进展。本文综述了硝酸盐还原体系中几种典型毒害性有机污染物(多环芳烃、单环或杂环芳烃类有机物及卤代有机物)的厌氧降解研究进展。在此基础上,提出了硝酸盐还原促进毒害性有机污染物降解研究中存在的主要问题及其在加速污染环境净化方面的应用前景。     

污染物降解成为环境微生物领域研究的重点

<正>根据《微生物学通报》2013年发表的文章分析,环境微生物学领域的论文有32篇,平均每个月在2篇以上,论文数显著多于农业微生物学(20篇)和工业微生物学(18篇)及其他领域。然而,在环境微生物学领域中,有关污染物降解方面的文章达到了12篇。就本刊数据而言,这体现了污染物的降解已成为我国环境微生物学研究领域的重点。其中有10项研究工作,针对各种有机化合物的处理与降解,如石油[1]、包     

水生植物-微生物联合去除水体有机污染物的研究进展

近年来,随着经济的快速发展,大量有机化合物随着工业废水和生活污水排放进入水体,严重破坏了水环境的生态平衡,威胁着水生生物及人类健康。植物-微生物联合修复技术因具有修复效率高、持续时间长、投入成本低,而且不会产生二次污染等特点,在水体有机污染治理中受到了人们的广泛关注。本文综述了近年来水生植物-微生物联合去除水体有机污染物的应用现状,详细阐述了水生植物-微生物联合修复过程中的研究方法、作用机制及影响因素。以期不断完善和优化水生植物-微生物联合修复技术,为实现水环境有机物污染的统筹高效治理提供参考。     

人工湿地中降解有机污染物细菌的分离筛选

采用平板划线法从人工湿地污水处理系统底泥和污水中分离出 2 3株细菌 ,在实验室条件下检测了这些细菌对灭菌污水和自然污水CODcr的去除效果 ,结果表明其中 8株细菌 (DN -4、DN -5、DN- 6、DN -10、DN -11、DN -12、DN- 13、WS- 5 )对灭菌污水和自然污水的CODcr均有较高的去除率 ,胞外酶检测表明该 8株细菌均能产生淀粉酶和接触酶 ,这些细菌具有潜在的应用价值。     

土壤中高分子量PAHs微生物降解机理及影响因素研究进展

高分子量多环芳烃( HMW PAHs)分子结构复杂,疏水性强,是环境中广泛存在的难降解的有机污染物.微生物降解是去除HMW PAHs的主要途径.本文介绍了PAHs降解菌株的种类和降解机理,以及不同环境因子(营养元素、pH值、土壤结构、通气状况和复合污染)对HMW PAHs降解的影响,提出HMW PAHs污染土壤的进一步研究的方向与重点,旨在为HMW PAHs污染修复研究和微生物降解机理研究提供参考.     

Degradation of Imidacloprid in Liquid by Enterobacter sp. Strain ATA1 Using Co-Metabolism

Imidacloprid (IMI), a potent insecticide, belongs to the neonicotinoid family and is of great concern due to the fact that its persistence in the soil is a threat to both plants and vertebrates. The present study was aimed at the isolation and characterization of a bacterial strain from paddy field soil at Punjab (India), which has a history of 9–10 years of imidacloprid contamination. Among the various isolates, a soil bacterium was selected and identified by 16S rRNA gene sequencing as Enterobacter sp. strain ATA1. It grew well in pH ranging from 6.0 to 7.0 at 37°C, and it was found to be a competent bacterium for the degradation of IMI. The presence of glucose in minimal salt medium (MMG; 0.1% w/v) as compared with any other co-substrate provokes the dissipation of IMI as a co-metabolite. Initially, incubation of IMI for 72 h in the MMG resulted in 30–40% degradation; thereafter, no significant change in its amount was found until 15 days of incubation, which explains the disappearance of any viable cells in the medium. Among the various identified metabolites, imidacloprid urea (m/z = 212) and imidacloprid guanidine (m/z = 211) were found to be the end products of IMI degradation, whereas others remained unidentified (m/z = 99 and m/z = 119).     

Persistent Organic Pollutants and Early Menopause in U.S. Women

Objective

Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determine the association of EDC exposure with earlier age of menopause.

Methods

Cross-sectional survey using National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2008 (n = 31,575 females). Eligible participants included: menopausal women >30 years of age; not currently pregnant, breastfeeding, using hormonal contraception; no history of bilateral oophorectomy or hysterectomy. Exposures, defined by serum lipid and urine creatinine-adjusted measures of EDCs, data were analyzed: > 90^th percentile of the EDC distribution among all women, log-transformed EDC level, and decile of EDC level. Multi linear regression models considered complex survey design characteristics and adjusted for age, race/ethnicity, smoking, body mass index. EDCs were stratified into long (>1 year), short, and unknown half-lives; principle analyses were performed on those with long half-lives as well as phthalates, known reproductive toxicants. Secondary analysis determined whether the odds of being menopausal increased with EDC exposure among women aged 45–55 years.

Findings

This analysis examined 111 EDCs and focused on known reproductive toxicants or chemicals with half-lives >1 year. Women with high levels of β-hexachlorocyclohexane, mirex, p,p’-DDE, 1,2,3,4,6,7,8-heptachlorodibenzofuran, mono-(2-ethyl-5-hydroxyhexyl) and mono-(2-ethyl-5-oxohexyl) phthalate, polychlorinated biphenyl congeners −70, −99, −105, −118, −138, −153, −156, −170, and −183 had mean ages of menopause 1.9 to 3.8 years earlier than women with lower levels of these chemicals. EDC-exposed women were up to 6 times more likely to be menopausal than non-exposed women.

Conclusions

This study of a representative sample of US women documents an association between EDCs and earlier age at menopause. We identified 15 EDCs that warrant closer evaluation because of their persistence and potential detrimental effects on ovarian function. Earlier menopause can alter the quantity and quality of a woman’s life and has profound implications for fertility, human reproduction, and our global society.     

Integrated Human and Ecological Risk Assessment: A Case Study of Persistent Organic Pollutants (POPs) in Humans and Wildlife

Since the mid-1900s, the global environment has become increasingly contaminated with Persistent Organic Pollutants (POPs), including many with dioxin-like properties. These compounds generally have low water solubility, do not degrade readily in the environment, bioaccumulate in food chains, and have been linked to adverse health effects in both humans and wildlife. The presence of such compounds in terrestrial and aquatic food chains is relevant to those concerned with both human health and environmental protection because of the many common exposure pathways and biological effects among different species. In the past, some chemicals with health risks for humans have been identified following reports of adverse effects in wildlife. Integrating human and ecological risk assessments may improve society's ability to manage the design, manufacture, use and disposal of chemicals in a safe and efficient manner. This can be demonstrated with this case study, which summarizes approaches to evaluating the sources, transport and fate of certain POPs, used largely in the past, and their associated health risks to humans and biota.     

转基因植物对有机污染物的吸收、转化和降解

有机污染物是土壤、水体和大气环境的重要污染物.利用和加强植物修复作用是控制环境污染的有效途径.近年来,一些具有修复功能的外源基因被陆续引入到植物中,使转基因植物的生物修复能力大大增强.文章介绍了植物对污染环境中有机污染物,尤其是持久性有机污染物(POPs)的吸收、转化和降解作用,阐述了转基因植物用于被污染环境修复方面的研究进展和应用前景.     

沈阳西部污灌水中有机污染物的分析

沈阳西部污灌水中有机污染物的分析刘海玲,张丽珊,姚家彪,于殿臣,朱岩,可夫,姜萍（中国科学院沈阳应用生态研究所,１１００１５）ＡｎａｌｙｓｉｓｏｆＯｒｇａｎｉｃＰｏｌｌｕｔａｎｔｓｉｎＩｒｒｉｇａｔｅｄｓｅｗａｇｅＩｎＷｅｓｔｅｒｎＳｈｅｎｙａｎｇ．...     

A Major Latex-Like Protein Is a Key Factor in Crop Contamination by Persistent Organic Pollutants

This is the first report, to our knowledge, to reveal important factors by which members of the Cucurbitaceae family, such as cucumber (Cucumis sativus), watermelon (Citrullus lanatus), melon (Cucumis melo), pumpkin (Cucurbita pepo), squash (C. pepo), and zucchini (C. pepo), are selectively polluted with highly toxic hydrophobic contaminants, including organochlorine insecticides and dioxins. Xylem sap of C. pepo ssp. pepo, which is a high accumulator of hydrophobic compounds, solubilized the hydrophobic compound pyrene into the aqueous phase via some protein(s). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of xylem sap of two C. pepo subspecies revealed that the amount of 17-kD proteins in C. pepo ssp. pepo was larger than that in C. pepo ssp. ovifera, a low accumulator, suggesting that these proteins may be related to the translocation of hydrophobic compounds. The protein bands at 17 kD contained major latex-like proteins (MLPs), and the corresponding genes MLP-PG1, MLP-GR1, and MLP-GR3 were cloned from the C. pepo cultivars Patty Green and Gold Rush. Expression of the MLP-GR3 gene in C. pepo cultivars was positively correlated with the band intensity of 17-kD proteins and bioconcentration factors toward dioxins and dioxin-like compounds. Recombinant MLP-GR3 bound polychlorinated biphenyls immobilized on magnetic beads, whereas recombinant MLP-PG1 and MLP-GR1 did not. These results indicate that the high expression of MLP-GR3 in C. pepo ssp. pepo plants and the existence of MLP-GR3 in their xylem sap are related to the efficient translocation of hydrophobic contaminants. These findings should be useful for decreasing the contamination of fruit of the Cucurbitaceae family as well as the phytoremediation of hydrophobic contaminants.Numerous agricultural fields and crops have been contaminated with persistent organic pollutants (POPs), including dioxins, such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs); dioxin-like compounds, such as coplanar polychlorinated biphenyls (PCBs) and the insecticide dichlorodiphenyltrichloroethane; drins, such as aldrin, dieldrin, and endrin; and chlordane (Hashimoto, 2005; Uegaki et al., 2006; Hilber et al., 2008). POPs show carcinogenicity, teratogenicity, immunotoxicity, and estrogenicity toward humans and wildlife after accumulation through the food chain. Despite the fact that the use of PCBs and these insecticides was prohibited several decades ago, environmental and crop contamination remains a problem due to their high hydrophobicity and chemical stability.Members of the Cucurbitaceae family, such as cucumber (Cucumis sativus), watermelon (Citrullas lanatus), melon (Cucumis melo), pumpkin (Cucurbita pepo), and zucchini (C. pepo), are some of the major crops in the world. Previous studies reported that members of the Cucurbitaceae family, particularly C. pepo, which includes pumpkin and zucchini, accumulated higher levels of PCDDs and PCDFs (Hülster et al., 1994; Inui et al., 2008), 2,2-bis(p-chlorophenyl) 1,1-dichloroethylene (p,p′-DDE; White et al., 2003), PCBs (Aslund et al., 2008; Inui et al., 2008), chlordane (Mattina et al., 2004), and drins (Otani et al., 2007) compared with the levels in other plant species. Thus, it appears that the Cucurbitaceae family has unique mechanisms of POP uptake and translocation. Lunney et al. (2004) reported that the shoots of pumpkin and zucchini plants showed much higher concentrations of dichlorodiphenyltrichloroethane than those of tall fescue (Festuca arundinacea), alfalfa (Medicago sativa), and ryegrass (Lolium multiflorum), whereas concentrations in roots were similar among these plants. Likewise, significant differences were found between C. pepo ssp. pepo and ssp. ovifera in concentrations of dioxins and dioxin-like compounds in the aerial parts, whereas the concentrations in their roots were similar (Inui et al., 2011). These results suggest that the mechanisms causing the high accumulation of POPs in C. pepo plants mainly occur during translocation from the roots to the aerial parts.The transport of substances such as nutrients and signal molecules over long distances in higher land plants is mediated by the vascular bundles, which consist of phloem and xylem strands. In addition to inorganic salts, organic nutrients such as amino acids, sugars, and organic acids are translocated through the xylem from the roots to the aerial parts (Satoh, 2006). Furthermore, the fact that POPs such as chlordane, dieldrin, and PCBs were detected in xylem sap of C. pepo suggests that their accumulation in the aerial parts of plants occurs during the translocation from roots to aerial parts in xylem sap (Mattina et al., 2004; Murano et al., 2010b; Greenwood et al., 2011). A recent study revealed that there were protein-like materials with the ability to dissolve dieldrin in xylem sap (Murano et al., 2010a). However, these materials have yet to be identified, and the mechanisms underlying the high transport ability and high accumulation of POPs in C. pepo plants are not fully understood.In this study, to clarify the molecular mechanisms of the efficient uptake and high accumulation of POPs by C. pepo plants, xylem sap proteins related to the transport of POPs in xylem sap were identified. The aim of this research is to provide a means of preventing cucumber, melon, watermelon, pumpkin, and zucchini fruits from being contaminated by POPs.     

微生物表面展示技术及其在环境污染治理中的应用

微生物表面展示技术是通过基因工程手段,将短的外源肽或蛋白质表达在微生物细胞表面,该技术可以应用于开发活的细菌疫苗、筛选抗体库、生产生物细胞吸附剂以及制备整细胞生物催化剂。通过金属高效结合肽的肽库筛选和微生物展示技术,将金属结合肽直接展示在微生物的表面,用于处理环境中的重金属污染,为环境中重金属污染的防治提供了一条崭新的途径。利用微生物表面展示技术制备整细胞催化剂,用于有毒有机污染物的处理,可以极大地加快污染物的降解速率。简要介绍了微生物表面展示技术及其在重金属污染治理和毒性有机污染物的脱毒等环境生物修复方面的最新研究进展。     

Volatile Organic Compounds and Their Roles in Bacteriostasis in Five Conifer Species

In order to make clear the functions of plant volatile organic compounds (VOCs) on bacteriostasis and air decontamination, we analyzed the composition and content of VOCs in Pinus tabulaeformis Carr., P. bungeana Zucc., Sabina chinensis Antoine, Picea koraiensis Nakai, and Cedrus deodara G. Don under near-natural conditions using the thermal-desorption cold trap gas chromatography/mass spectrometer technique. The effects of the VOCs on airborne microorganisms were investigated using the method of natural sedimentation. Results showed that the major VOCs were as follows: limonene, β-pinene, α-pinene,and α-caryophyllene in Pinus tabulaeformis and P. bungeana; limonene, borneol acetate, β-pinene, myrcene,and tricylene in S. chinensis; limonene, α-pinene, myrcene, camphene, and β-pinene in Picea koraiensis;and limonene, 2, (10)-pinene, α-pinene, and myrcene in C. deodara. These VOCs and the corresponding foliar extracts inhibited the growth of bacteria and stimulated the growth of fungi. Experimental data using monomers of the VOCs demonstrated that limonene, β-pinene, and three aldehydes could significantly inhibit bacterial growth, suggesting an inhibitory effect of VOCs on the growth of airborne microorganisms in the five conifer species. The bacteriostasis and air-decontaminating effects of plant VOCs are further discussed in terms of their chemical composition.