在生态系统中,排放含有重金属的制革废水是当今社会面临的最重要的环境和健康挑战之一。 重金属无法进行生物降解,且对微生物具有毒性作用,仅有少数微生物对重金属的抗性和解毒作用。 因此,针对被排放到环境中的无机金属(铬、汞、镉和铅),人类社会需要更多地开发新式、高效、环保以及紧急的生物修复法,从而保护整个生态系统。 近期,Hindawi的开放获取期刊 Journal of Toxicology 发表了一篇 高被引文章 :Toxicity and Bioremediation of Heavy Metals Contaminated Ecosystem from Tannery Wastewater: A Review 。 该文对微生物的生物修复能力做出了重要的评估,特别是在环境保护方面。此外,本文还探讨了利用细菌、真菌、生物膜、藻类、基因工程微生物(genetically engineered microbes)和固定化微生物(immobilized microbial cell)细胞去除重金属生物吸附的能力。在污染微生物的重金属方面所取得的最新突破推动了生物修复技术的进步,使其有望成为传统技术的替代方案。 Figure 1: Mechanisms of heavy metal uptake by microorganisms 在移除重金属方面,生物膜的使用已经显现出了协同效应。作为可持续的环境技术,生物膜有望在不久的将来实现重金属去除的高效化。 点击查看阅读原文 由查尔斯沃思集团(Charlesworth Group)统筹翻译。
有机食品比普通食品具有更高的营养品质与安全性 虞晓凡 郭立月 蒋高明 宋彦洁 玛德·雷姆诺夫 有机食品来源于有机生产系统,遵循有机农业种植标准,生产过程必须由独立的认证机构确认。有机农业生产系统的主要特点是不能使用农药、化肥、生长调节剂、饲料添加剂、基因工程产品等人工合成材料。然而,学术界对有机食品质量和健康安全方面存在的争论很多。有人认为有机生产存在“三不出”现象,即有机产品“看不出,尝不出,测不出”。为了客观地反映有机食品和常规食品在营养品质和食品安全的差异,本文查阅大量文献,结合自己的研究数据,介绍两类产品在感官质量、营养价值和安全性方面的研究进展。结果表明,有机产品味道更好,风味物质比例高,吃起来更劲道;有机作物干物质含量比常规食品高出7~20%;含有更丰富的维生素C、花青素、异黄酮、类胡萝卜素和其他酚类化合物;磷、铁、Mg等微量元素,锌、铜、铬等微量元素在有机作物中含量较高。有机畜产品中含有较多的有益不饱和脂肪酸;有机水果和蔬菜中的硝酸盐含量为正常水果的20~50%。有机产品中无农药残留,重金属含量低。本研究表明,来源于有机农业系统的产品与传统产品之间存在明显质量和安全性差异,这一结论可为有机产业健康发展提供重要的科学依据。 本文载《生态学报》英文版 38 (2018) 53–60,2018. Advances of organic products over conventional productions with respect to nutritional quality and food security ·Xiaofan Yua, b, c, 1, Liyue Guoa, b, 1, Gaoming Jianga, b, , , Yanjie Songa, b, Mahmud Abdimuratovich Muminova, b ·a Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China ·b University of Chinese Academy of Sciences, Beijing 100049, China ·c College of Pharmacy, Anhui Medical University, Anhui 230032, China Received 3 September 2016, Revised 30 November 2016, Accepted 13 January 2017, Available online 17 February 2018 Acta Ecologica Sinica 38 (2018) 53–60, 2018 Organic products are derived from the organic production system, following organic agricultural cultivation standards, and processing schedules must be identified by an independent certificate authority. The main characteristic of the organic agricultural production system is that all artificial synthetic materials such as pesticides, fertilizers, growth regulators, feed additives, and gene engineering products are not allowed to use. However, there is much debate on organic production quality and health safety issues in academic circles. Some people believe that there is a “Three Cannot” problem with organic production, that is, organic products “cannot be distinguished, cannot be tasted and cannot be measured” compared to common ones. To objectively reflect the differences in nutritional quality and food safety between organic and conventional products, we combined extensive literatures with our research data and have reported some advances in the sensory quality, nutritional value, and safety of the two types of products. The results showed that organic products tasted better; the percentage of leanness was higher, and the products tasted much tender. The dry matter content of most organic crops was about 7–20% higher than that of conventional foods, and enriched vitamin C, anthocyanins, isoflavones, carotenoids, and other phenolic compounds and more elements such as P, Fe, and Mg and trace elements such as Zn, Cu, and Cr were verified in organic crops. Organic animal products contain more beneficial polyunsaturated fatty acids; the nitrate content in organic fruits and vegetables was 20–50% of that in normal fruits. No pesticide residues and less heavy metals were found in the organic products. Our investigation showed that there were obvious differences in quality and safety between the products that originated from organic agriculture systems and conventional alternatives. This conclusion can provide an important theoretical basis for the healthy development of the organic industry.
这是一篇比较早的论文了,是最近关注一个治理重金属和有机物污染的研究人员时看到的,由于本人对重金属的治理比较感兴趣,所以,特意看了一下该文章。 这种植物能够将土壤中的As运送到枝干以上部分,这样对土壤中As去除是非常有意义的。 由这个表可以看出,该植物对As的富集能力确实是非常的强,而且,该植物能够本身也是一种As抗性植物,能够耐受如此高的As浓度。 其实,一般重金属去除中,最难但又亟待处理的要算是Cd了,但是,由于原子特性的差异,Cd的去除一直都比Pb,As的去除要难很多,而且毒性还非常高。 参见: A fern that hyperaccumulates arsenic
BRIEF NOTE The Health of Immigrants to New York City From Mainland China: Evidence From the New York Health Examination and Nutrition Survey PETER MUENNIG, YUE WANG, and ALEKSANDRA JAKUBOWSKI Mailman School of Public Health, Department of Health Policy and Management, Columbia University, New York, New York, USA Very little is known about the newest New Yorkers of Chinese heritage, the largest and fastest growing immigrant group in the city. This article compares measures of the health of immigrants to New York from Mainland China to the health of other New Yorkers of Asian heritage along with all other New Yorkers. We did so using the 1,999 subjects in the 2004 New York Health and Nutrition Examination Survey, controlling for age and gender. We found that New Yorkers born in Mainland China have a lower body mass index, a smaller waist circumference, a more sexually conservative lifestyle, highly favorable high-density lipoprotein profiles, and lower rates of herpes II infection. However, they also have higher blood levels of lead, cadmium, and mercury than either reference group . This article provides the first study of the health needs of New York’s largest and most rapidly growing immigrant group http://www.pceo.org/pubs/JIRS%20Chinese.pdf
柏克利坑(Berkeley Pit)曾是位于美国蒙大拿州的比尤特露天铜矿。它有一个一英里长半英里宽,近似深度为1780英尺约合540米的湖。湖泊里流淌着30000000000加仑的金属污染的水,酸度达到pH 2.5。尽管湖水高度酸性,而且里面充满了有毒的重金属,但也长满了奇异的菌类。 一般认为,在有毒的水中,正常形式的水生生物难以生长,但这里已被证明它是一个具有丰富的独特和不同的真菌、藻类、细菌的环境,可以提供了不寻常的分子以供研究人员用于药物开发。这种艰苦的环境中被证明是一个不寻常的微生物产生新的生物活性代谢物的来源。 2006年,Montana理工大学化学系Andrea A. Stierle,* Donald B. Stierle和Kal Kelly报道从柏克利露天铜矿坑湖水 penicillium fungus 中分离得到一种新的螺缩酮,他们给它命名为柏克利酸(Berkelic Acid),初步试验表明这种微生物来源的螺缩酮对卵巢癌细胞株OVCAR-3体外抑制浓度达到纳摩尔级,有报道称是色烷caspase和金属蛋白酶MMP-3抑制剂。 Auckland大学教授Margaret Brimble打算合成柏克利酸,人工合成化学结构复杂的柏克利酸会帮助研究人员开发了一个治疗卵巢癌的抗癌药,同时也可以更好地了解分子如何发挥功能并且为进一步研究提供一个现成的来源。已从Marsden基金会获720000美元资助,计划在用三年的时间开展这项研究。2012年1月,在JOC发表了他们合成柏克利酸的论文。Margaret Brimble等证明插入的C-18位甲基具有挑战性,并介绍了用三种不同的方法安装这一官能团的立体化学研究。他们最初设计的用Horner-Wadsworth-Emmons/oxa-Michael方法建立柏克利酸核被证明是不成功的。然而,通过向氧鎓离子引入一个甲硅烷基烯醇,然后采用一勺烩脱苄基/缩酮化/热力学平衡的方法,提供了作为单一非对映异构体柏克利酸核的四环结构。 2009年,Brandeis大学的Snider BB和Zhou J进行了柏克利酸的合成研究。尽管斯奈德“13步”合成路线并不是一条最佳途径,但确实向世界同行提供了深入了解这一潜在抗癌药物全合成的途径和方法。 2012年,Faanás FJ、Mendoza A、Arto T、Temelli B和Rodríguez F等报道了柏克利酸的规模化全合成。 附部分研究文献 1.Scalable total synthesis of (-)-berkelic Acid by using a protecting-group-free strategy. Faanás FJ, Mendoza A, Arto T, Temelli B, Rodríguez F. Angew Chem Int Ed Engl. 2012 May 14;51(20):4930-3. doi: 10.1002/anie.201109076. Epub 2012 Apr 4. 2.Formal synthesis of berkelic acid: a lesson in α-alkylation chemistry. McLeod MC, Wilson ZE, Brimble MA. J Org Chem. 2012 Jan 6;77(1):400-16. Epub 2011 Nov 28. 3.An enantioselective formal synthesis of berkelic acid. McLeod MC, Wilson ZE, Brimble MA. Org Lett. 2011 Oct 7;13(19):5382-5. Epub 2011 Sep 14. 4.A diastereoselective formal synthesis of berkelic acid. Wenderski TA, Marsini MA, Pettus TR. Org Lett. 2011 Jan 7;13(1):118-21. Epub 2010 Dec 7. 5.Total synthesis of berkelic acid. Snaddon TN, Buchgraber P, Schulthoff S, Wirtz C, Mynott R, Fürstner A. Chemistry. 2010 Oct 25;16(40):12133-40. 6.A flexible asymmetric synthesis of the tetracyclic core of berkelic acid using a Horner-Wadsworth-Emmons/oxa-Michael cascade. Wilson ZE, Brimble MA. Org Biomol Chem. 2010 Mar 21;8(6):1284-6. Epub 2010 Jan 26. 7.A concise synthesis of berkelic acid inspired by combining the natural products spicifernin and pulvilloric acid. Bender CF, Yoshimoto FK, Paradise CL, De Brabander JK. J Am Chem Soc. 2009 Aug 19;131(32):11350-2. Erratum in: J Am Chem Soc. 2010 Jun 16;132(23):8223. 8.Introduction of the (-)-berkelic acid side chain and assignment of the C-22 stereochemistry. Wu X, Zhou J, Snider BB. J Org Chem. 2009 Aug 21;74(16):6245-52. 9.A Cycloaddition Strategy for Use toward Berkelic Acid, an MMP Inhibitor and Potent Anticancer Agent Displaying a Unique Chroman Spiroketal Motif. Huang Y, Pettus TR. Synlett. 2008 May 11;9:1353-1356. 10.Synthesis of (-)-berkelic acid. Wu X, Zhou J, Snider BB. Angew Chem Int Ed Engl. 2009;48(7):1283-6. 11.A synthesis-driven structure revision of berkelic acid methyl ester. Buchgraber P, Snaddon TN, Wirtz C, Mynott R, Goddard R, Fürstner A. Angew Chem Int Ed Engl. 2008;47(44):8450-4. No abstract available. 12.Generation and hetero-Diels-Alder reactions of an o-quinone methide under mild, anionic conditions: rapid synthesis of mono-benzannelated spiroketals. Bray CD. Org Biomol Chem. 2008 Aug 7;6(15):2815-9. Epub 2008 May 28. 13.Biomimetic synthesis of the tetracyclic core of berkelic acid. Zhou J, Snider BB. Org Lett. 2007 May 24;9(11):2071-4. Epub 2007 Apr 28. 14.Berkelic acid, a novel spiroketal with selective anticancer activity from an acid mine waste fungal extremophile. Stierle AA, Stierle DB, Kelly K. J Org Chem. 2006 Jul 7;71(14):5357-60.
Journal Bacteriol.2012年2月版发表了通讯作者韦革宏教授等人的一株根瘤菌的全基因组测序结果。Mesorhizobium amorphae CCNWGS0123是一株能耐重金属,且具有植物促生作用及结瘤固氮功能的紫穗槐中慢生根瘤菌,其全基因组草图的发表将有利用该菌株与其共生体——刺槐一起在重金属污染土壤中进行生物修复打下基础。尽管如此,我还是希望人们不要因此还去先污染,再用什么高效生物修复系统去修改环境,这是得不偿失的。如同这蒋先生的博文: http://blog.sina.com.cn/s/blog_4b6ea01901000bbm.html 中提到:“直到今天,生态学家依然辛苦地在寻找所谓的重金属超富集植物,而不去告诉公众重金属就是“水泊梁山”里的“地煞星”,一旦释放出来就难以让它们回去,而不让它释放是有办法的。” 我自己做根瘤菌多样性和进化研究的,该文的发表对从全基因组角度研究根瘤菌的起源、进化和重组将有很大的帮助。 论文题目: Draft Genome Sequence of Plant Growth-Promoting Rhizobium Mesorhizobium amorphae, Isolated from Zinc-Lead Mine Tailings 摘要: Here, we describe the draft genome sequence of Mesorhizobium amorphae strain CCNWGS0123, isolated from nodules of Robinia pseudoacacia growing on zinc-lead mine tailings. A large number of metal(loid) resistance genes, as well as genes reported to promote plant growth, were identified, presenting a great future potential for aiding phytoremediation in metal(loid)-contaminated soil. 全文: http://jb.asm.org/content/194/3/736.full
开发了一种颗粒模型用于流化床中市政固体废弃物焚烧,包括固体废弃物颗粒燃烧以及重金属挥发。基于一个先前的简化的,非等温版本,该模型包含了一个 asymptotic combustion (渐近)模型用于含碳固体燃烧以及一个 shrinking-core 模型用来描述重金属挥发现象,颗粒在该模型当中被认为是非等温过程。本文的参数研究显示了温度对金属挥发过程的影响。简化的非等温模型的模拟结果和来自于一个实验室规模的流化床燃烧器获得的实验数据进行对比。结果显示颗粒传导会强烈的影响挥发速率和时间的变化关系,目前版本的模型可以很好的拟合床温条件下 the shape of the plots 以及最大重金属挥发速率。