地下水受到含氯有機物污染的問題近年來已經逐漸受到重視，其中三氯乙烯(trichloroethylene, TCE)為地下水體中常見重質非水相液體(dense non-aqueous phase liquids, DNAPLs)污染物，具有潛在之基因突變性及致癌性等毒性特徵，若發生洩漏或人為不當之排放，將容易經由各種途徑對環境或人民健康造成危害。聚麩胺酸(poly-(γ-glutamic acid), γ-PGA)是一種經由生化合成之高分子聚合物，由於具有保濕性、高黏性、無毒性、金屬螯合性、生物可分解性及生體相容性等特性，已在各工業領域上有廣泛之運用。本研究以γ-PGA為微生物生長之基質，在厭氧的環境下還原脫氯TCE污染物，進行了批次實驗瞭解其生物降解污染物能力，並結合變性梯度膠體電泳(denaturing gradient gel electrophoresis, DGGE)觀察前後菌相變化，以及針對各實驗組別具有脫氯作用菌群及還原脫氯功能基因的消長變化以即時定量(real-time PCR)分析。研究結果顯示，批次實驗中γ-PGA組具有最佳之降解效率，TCE初始濃度4.23 mg/L在42天內可持續穩定降解至0.26 mg/L，反應至84天濃度剩餘0.012 mg/L，降解效率高達99%，已低於地下水污染管制標準(0.05 mg/L)。乳化油組在第28天之後pH迅速下降至5.95，至84天pH值為5.66，呈現酸化之情形，而γ-PGA組pH值在第84天仍在7.32，維持良好之中性環境。γ-PGA總有機碳初始濃度1977.5 mg/L，在第84天後之殘餘量為646 mg/L，生物利用率為67.3%，乳化油初始濃度為841.5 mg/L，在第84天後為492.3 mg/L 生物利用率為41%。分子生物分析結果，DGGE菌相圖顯示γ-PGA可促使環境中之菌相之豐富度增加。real-time PCR各組別初始Dehalococcoides spp. (Dhc)菌量約為104 gene copies/g，γ-PGA於84天增加到1.49×106 gene copies/g，生長效果較乳化油於84天之9.4×104 gene copies/g顯著。上述成果證實以γ-PGA加強三氯乙烯之厭氧還原脫氯方法，除了具有pH衝能力能避免以往釋碳基質有酸化之情況之外，其總有機碳含量高，可提供大量且穩定之碳源供微生物利用且可利用性顯著，營造適合還原脫氯菌群生長環境，達到污染物降解之目的，且不會有微生物抑制之情形，為一有效之加強式生物降解法。

Groundwater at many existing and former industrial areas and disposal sites are contaminated by halogenated organic compounds that were released into the environment. Trichloroethylene (TCE) is one of the most commonly found halogenated organic compounds in groundwater. Application of in situ anaerobic bioremediation is a feasible technology to remediate TCE-contaminated site. However, enhanced in situ bioremediation requires the injection of primary substrates. The poly-(γ-glutamic acid) (γ-PGA) is a biopolymer synthesized by biochemical processes. Due to its characteristics of moisture resistance, high viscosity, no toxicity, and chelating ability with metals, it has been widely applied by the industry. In this study, microcosm study was performed to evaluate the feasibility of using γ-PGA as a primary substrate to enhance the dechlorinating process of TCE under anaerobic conditions. Molecular biological techniques [e.g., PCR-DGGE (polymerase chain reaction-denatured gradient gel electrophoresis), real-time PCR] were used to evaluate the microbial diversity and variations in dominant bacterial species during the microcosm study. Results indicate that the γ-PGA could be used as the substrate and resulted in the TCE dechlorinating TCE effectively. Results show that TCE concentrations dropped from 4.23 to 0.26 mg/L within 42 days of operation. Up to 99% of TCE could be removed after 84 days of operation. In microcosms with emulsified oil addition, pH dropped to 5.7 after 84 days of operation. Results show that the pH remained neutral (pH = 7.32) in microcosms with γ-PGA addition after 84 days of incubation. This indicates that γ-PGA had good buffering capacity during the anaerobic processes. The total organic carbon (TOC) concentrations in microcosms dropped from 1,978 to 646 mg/L after 84 days of operation. The significant decrease in TOC concentrations indicate that the γ-PGA was consumed by microbial consortia in microcosms causing the shifting of oxidation-reduction potential from aerobic to anaerobic conditions, which favored the occurrence of reductive dechlorination. The population of Dehalococcoides spp. increased from 1×104 to 1.5×106 after 84 days of operation in PGA addition microcosms. This indicates that the addition of γ-PGA enhanced the growth of Dehalococcoides spp., which could significantly activate the TCE dechlorination. The addition of γ-PGA created anaerobic conditions and leaded to a more complete TCE removal via biodegradation mechanisms. Results show that the enhanced anaerobic bioremediation is an effective and applicable technology to remediate TCE-contaminated groundwater.

謝誌 i
摘要 ii
Abstract iii
目錄 v
圖目錄 viii
表目錄 x
第一章 前言 1
1.1 研究緣起 1
1.2 研究目的 2
第二章 文獻回顧 3
2.1 含氯有機污染物 3
2.1.1 含氯有機污染物污染概況 3
2.1.2 含氯有機污染物之性質與危害 5
2.2 現地地下水污染整治技術 9
2.3 三氯乙烯污染地下水生物處理技術 11
2.4 三氯乙烯生物反應機制 15
2.4.1 好氧共代謝 17
2.4.2 厭氧還原脫氯 20
2.5 以基質加強三氯乙烯還原脫氯 22
2.6 分子生物技術應用在環境監測 24
2.6.1 PCR-DGGE 24
2.6.2 及時定量分析 24
2.7 聚麩胺酸 24
2.7.1 聚麩胺酸介紹 24
2.7.2 γ-PGA在環境上之應用 27
第三章 實驗設備及方法 30
3.1 實驗藥品及器材 32
3.1.1 實驗藥品 32
3.1.2 實驗器材 33
3.2 污染地下水配置 33
3.3 廢水場污泥 33
3.4 聚麩酸胺 34
3.5 微生物厭氧批次實驗 35
3.6 實驗分析項目 37
3.6.1 水之氫離子濃度指數(pH值) 37
3.6.2 水中溶氧(DO) 37
3.6.3 總有機碳(TOC) 37
3.6.4 污染物及其中間產物分析 38
3.6.5 以分子生物技術分析微生物之菌相變化 39
3.6.5.1 微生物DNA萃取 40
3.6.5.2 聚合脢連鎖反應(Polymerase Chain Reaction，PCR) 41
3.6.5.3 變性梯度膠體電泳(Denaturing Gradient Gel Electrophoresis，DGGE) 42
3.6.5.4 及時定量分析(real-time PCR) 44
第四章 結果與討論 46
4.1 地下水基本性質 46
4.2 微生物厭氧批次實驗基本參數 46
4.3 γ-PGA組別污染物及中間產物 51
4.4 緩衝液γ-PGA組污染物及中間產物 52
4.5 緩衝液乳化油組污染物及中間產物 54
4.6 各組別降解效率比較 56
4.7 以即時定量還原脫氯酶 60
4.8 微生物菌相圖 63
第五章 結論與建議 65
5.1 結論 65
5.2 建議 66
參考文獻 67

王洪斌，成明，盛菊，楊艷艷，李士虎，閻斌倫，2011，γ-聚谷氨酸明膠膜對重金屬離子吸附特性研究，《湖北農業科學》2011年第19期。

王有盛，2003，促進厭氧生物處理四氯乙烯代謝方式之探討，國立中興大學環境工程學系碩士論文。

王嬙，陳智，陳永強，陳詠竹，徐非一，陽泰，霍蕾，孫啟玲，2005，γ-多聚谷氨酸吸附銅離子的研究，四川大學學報：自然科學版，2005年第3期。

李世偉，2005，以厭氧生物處理高濃度四氯乙烯之研究，國立台灣大學環境工程研究所碩士論文。

味丹公司，2015，γ-PGA水處理材料介紹與應用，味丹公司。

林財富，2008，土壤與地下水污染整治：原理與應用，中華民國環境工程學會。

林佩君，柯文慶，謝昌衛，2008，不同種類之γ-聚麩胺酸吸附重金屬的研究，大葉大學藥用植物與保健學系。

郭育嘉，2013，應用現地乳化油生物屏障處理受含氯有機物污染之地下水，國立中山大學環境工程研究所。

何佳諺，2003，懸浮式連續流甲苯共代謝三氯乙烯之研究，國立成功大學環境工程學研究所碩士論文。

何觀輝，2006，聚麩胺酸之結構特性與化學特性，化工資訊與商情。

吳群，徐虹，梁金豐，姚俊，2008，甘油對聚谷氨酸合成的貢獻，南京工業大學製藥與生命科學學院。

陳勇志，2011，以天然棉絮交聯聚麩胺酸去除水中鐵離子，高雄師範大學化學系碩士論文。

陳俊位，2014，聚麩胺酸之特性及其在農業上之應用，臺中區農業改良場特刊；122 期，P237 – 244。

雷世恩，1999，以生物處理法整治三氯乙烯及四氯乙烯污染之場址，國立中山大學環境工程研究所碩士論文。

黃聖智， 2012，奈米級零價鐵分散劑之生物可降解性及其對三氯乙烯自然生物降解影響之研究，國立暨南國際大學土木工程研究所碩士論文。

張文，張樹清，王學江，2014，γ-聚谷氨酸的微生物合成及在農業生產中的應用，中國農學通報(Chinese Agricultural Science Bulletin) 2014,30(6):40-45

簡華逸，2010，應用現地生物整治技術去除三氯乙烯污染之地下水，國立中山大學環境工程研究所博士論文。

環保署，2015，地下水污染管制標準，環署土字第1020109478號令。

環保署，2015，土壤污染管制標準，環署土字第1000008495號令。

Alvarez-Cohen, L., Speitel, Jr., GE., (2001), “Kinetics of aerobic cometabolism of chlorinated solvents”, Biodegradation 12, 105-126.

Ashiuchi, M., Kamei, T., Misono, Haruo., (2003), “Poly-γ-glutamic synthetase of Bacillus subtilis”, Journal of Molecular Catalysis B: Enzymatic, 23, 101-106.

Aulenta, F., Pera, A., Rossetti, S., Petrangeli, P. and Majone, M., (2007), “Relevance of side reactions in anaerobic reductive dechlorination microcosms amended with different electron donors”, Water Research, 41, pp.27-38.

Aulenta, F., Bianchi, A., Majone, M., Petrangeli Papini, M., Potalivo, M., Tandoi, V., (2005), “Assessment of natural or enhanced in situ bioremediation at a chlorinated solvent-contaminated aquifer in Italy: a microcosm study”, Environ. Int. 31, 185–190.

Amos, B.K, Christ, J.A, Abriola, L.M, Pennell, D. and Loffler, F.E., (2007), “Experinental evaluation and mathematical modeling of microbially enhanced petrachloroethene (PCE) dissolution”, Environmental Science and Technology, 41(3), 963-970.

Bajaj, I., Singhal, R., (2011). Poly (glutamic acid) – an emerging biopolymer of commercial interest”. Bioresour. Technol. 102, 5551–5561.

Chen, Y.M., Lin, T.F., Huang, C., Lin, J.C., Hsieh, F.M. (2007), “Degradation of phenol and TCE using suspended and chitosan-bead immobilized Pseudomonas putida”. Journal of Hazardous Materials 148, 660-670.

Chen, M., Abriola, L. M., Amos, B. K., Suchomel, E. J., Pennell, K. D., Löffler, F. E. and Christ, J. A., (2013), “Microbially Enhanced Dissolution and Reductive Dechlorination of PCE by a Mixed Culture: Model Validation and Sensitivity Analysis”, Journal of Contaminant Hydrology.

Chang, J., Zhong, Z. X., Xu, H., Yao, Z., Chen, R. Z., (2013). “Fabrication of Poly(γ-glutamic acid)-coated Fe3O4 Magnetic Nanoparticles and Their Application in Heavy Metal Remocal”. Chinese Journal of Chemical Engineering, 21(11), 1244-1250.

Chin, D. A., (2012) “Water-quality Engineering in Natural Systems: Fate and Transport Processes in the Water Environment”, Wiley. com.

Chanat,C.,Steve, C., Chainarong, S., Bruce, D., (2014), “Improving the treatment of non-aqueous phase TCE in low permeability zones with permanganate”, Journal of Hazardous Materials 268 (2014) 177–184.

Crane, R. A., Scott, T. B., (2012), “Nanoscale zero-valent iron: Future prospects for an emerging water treatment technology”, Journal of hazardous materials, 211, 112-125.

de Biase, C., Maier, U., Baeder‐Bederski, O., Bayer, P., Oswald, S. E., and Thullner, M., (2012), “Removal of volatile organic compounds in vertical flow filters: Predictions from reactive transport modeling”, Ground Water Monitoring & Remediation, 32(2), 106-121.

Damgaard, I., Bjerg, P. L., Jacobsen, C.S., Tsitonaki, A, Kerrn-Jespersen, H, Broholm, M. M.,(2013), “Performance of Full-Scale Enhanced Reductive Dechlorination in Clay Till”, Groundwater Monitoring & Remediation, pages 48–61, Winter 2013.

Dang ,J.M., Leong ,K.W.,(2007), “Myogenic induction of aligned mesenchymal stem cell sheets by culture on thermally responsive electrospun nanofibers”, Wiley Online Library

Fujii, H.,(1963), “On the formation of mucilage by Bacillus natto. Part III. Chemical constitutions of mucilage in natto (1)”, Nippon Nogeikagaku Kaishi, 37 (1963), pp. 407–411.

Findlay, M., Smoler, D., Fogel, S., (2011). “pH optimum for Dhc and the development of a low-pH-tolerant Dhc culture”, Proceedings of the First International Symposium on Bioremediation and Sustainable Environmental Technologies, Reno Nevada, June 27-30, 2011 (2011)

Goto, A., Kunioka, M., (1992). “Biosynthesis and hydrolysis of poly (γ-glutamic acid) from Bacillus subtilis”, IFO3335. Biosci. Biotech. Biochem. 56, 1031–1035.

He, J., Sung, Y., Dollhopf, M.E., Fathepure, B.Z., Tiedje, J.M., Löffler, F.E., (2002), “Acetate versus hydrogen as direct electron donors to stimulate the microbial reductive dechlorination process at chloroethene-contaminated sites ” Environ. Sci. Technol. 36, 3945–3952.

He, J., Ritalahti, K.M., Aiello, M.R. and Löffler, F.E., (2003), “Complete detoxification of vinyl chloride by an anaerobic enrichment culture and identification of the reductively dechlorinating population as a Dehalococcoides species”, Applied and Environmental Microbiology 69:996-1003.

He, F., Zhao, D. and Paul, C. (2010) “Field assessment of carboxymethyl cellulose stabilized iron nanoparticles for in situ destruction of chlorinated solvents in source zones”, Water Research, 44(7), 2360-2370.

He, J., Sung, Y., Krajmalnik-Brown, R., Ritalahti, K. M. and Loffler, F. E., (2005), “Isolation and characterization of Dehalococcoides sp. Strain FL2, a trichloroethene (TCE)- and cis-1,2-dichloroethene-respiring anaerobe”, Environmental Microbiology, 7, pp.1442-1450.

Hunkeler, D., Abe, Y., Broholm, M.M., Jeannottat, S., Westergaard, C., Jacobsen, C.S., Aravena, R. and Bjerg, P., (2011), “Assessing chlorinated ethene degradation in a large scale contaminant plume by dual carbon–chlorine isotope analysis and quantitative PCR”, Journal of Contaminant Hydrology, 119(1-4), 68-79.

Ho, G.H., Ho, T.I., Hsieh, K.H., Su, Y.C., Lin, P.Y., Yang, J., Yang, K.H., Yang, S.C., (2006), “γ-polyglutamic acid produced by Bacillus subtilis (natto): structural haracteristics, chemical properties and biological functionalities.”, J. Chin.Chem. Soc. 53, 1363–1384.

Harkness, M., Fisher, A., (2013), “Use of emulsified vegetable oil to support bioremediation of TCE DNAPL in soil columns”, Journal of Contaminant Hydrology, Pages 16–33.

Ishwar, B., Rekha, S., (2011), “Poly (glutamic acid) – An emerging biopolymer of commercial interest”, Bioresource Technology 102 (2011) 5551–5561.

Inbaraj, B.S., Chen, B.H., (2012), “In vitro removal of toxic heavy metals by poly(γ-glutamic acid)-coated superparamagnetic nanoparticles”, Int J Nanomedicine 2012;7:4419e32.

Inbaraj, B.S., Wang, J.S., Lu, J.F., Siao, F.Y., Chen, B.H.,(2014), Adsorption of toxic mercury(II) by an extracellular biopolymer poly(γ-glutamic acid), Bioresource Technology, Pages 200–207.

Johnson, D.R., Lee, P.K.H., Holmes, V.F. and Alvarez-Cohen, L., (2005), “An internal reference technique for accurately quantifying specific mRNAs by real-time PCR with application to the tceA reductive dehalogenase gene”, Applied and Environmental Microbiology 71:3866-3871.

Philips, J., Maes, N., Springael, D., Smolders, E., (2013), “Acidification due to microbial dechlorination near a trichloroethene DNAPL is overcome with pH buffer or formate as electron donor: Experimental demonstration in diffusion-cells”, Journal of Contaminant Hydrology ,Volume 147, April 2013, Pages 25–33

Kouznetsova, I., Mao, X., Robinson, C., Barry, D.A.,Gerhard, J.I., McCarty P.L.,(2010), “Biological reduction of chlorinated solvents: batch-scale geochemical modelling”, Water Resources, 33 (2010), 969–986

Kao, C. M., Chen, K. F., Chen, Y. L. and Chen. T. Y. (2004), “Biobarrier system for remediation of TCE-contaminated aquifers”, Bulletin of Environmental Contamination and Toxicology, 37(1), pp.87-93.

Kao, C.M., Chen, Y.L., Chen, S.C., Yeh, T.Y., Wu, W.S.,(2003), “Enhanced PCE dechlorination by biobarrier systems under different redox conditions”, Water Research, 37 (2003), 4885–4894.

Lal, R., Pandey, G., Sharma, P., Kumari, K., Malhotra, S., Pandey, R. and Oakeshott, J. G., (2010), “Biochemistry of microbial degradation of hexachlorocyclohexane and prospects for bioremediation”, Microbiology and Molecular Biology Reviews, 74(1), 58-80.

Lee, M.H., Clingenpeel, S.C., Leiser, O.P., Wymore, R.A., Sorenson, K.S., Watwood, M.E., (2008), “Activity-dependent labeling of oxygenase enzymes in a trichloroethene-contaminated groundwater site”, Environmental Pollution 153, 99 238-246.

Lien, H. L. and Wilkin R. T., (2005), “High-level arsenite removal from groundwater by zero-valent iron”, Chemosphere, 59, pp.377-386.

Löffler, F. E., Yan, J., Ritalahti, K. M., Adrian, L., Edwards, E. A., Konstantinidis, K. T. and Spormann, A. M., (2013) “Dehalococcoides mccartyi gen. nov., sp. nov., obligately organohalide-respiring anaerobic bacteria relevant to halogen cycling and bioremediation, belong to a novel bacterial class, Dehalococcoidia classis nov., order Dehalococcoidales ord. nov. and family Dehalococcoidaceae fam. nov., within the phylum Chloroflexi”, International Journal of Systematic and Evolutionary Microbiology, 63(Pt 2), 625-635.

Lee, P. K., Cheng, D., West, K. A., Alvarez‐Cohen, L. and He, J., (2013) “Isolation of two new Dehalococcoides mccartyi strains with dissimilar dechlorination functions and their characterization by comparative genomics via microarray analysis”, Environmental microbiology.

McCarty, P.L., 2010. Groundwater contamination by chlorinated solvents: history, remediation technologies and strategies. LLC 2010. In: Stroo, H.F., Ward, C.H. (Eds.), In Situ Remediation of Chlorinated Solvent Plumes. Springer Science +Business Media, New York, pp. 1 e28.

Morrison, S. J., Metzler, D. R., and Dwyer, B. P. (2002) “Removal of As, Mn, Mo, Se, U, V and Zn from groundwater by zero-valent iron in a passive treatment cell: reaction progress modeling”, Journal of Contaminant Hydrology, 56, pp.99-116.

Miyata, R., Adachi, K., Tani, H., Kurata, S., Nakamura, K., Tsuneda, S., Sekiguchi, Y. and Noda, N., (2010), “Quantitative detection of chloroethene-reductive bacteria Dehalococcoides spp. Using alternately binding probe competitive polymerase chain reaction”, Mol. Cell. Probes., 24(3), 131-137.

Matturro, B., Aulenta, F., Majone, M., Papini, M.P., Tandoi, V. and Rossetti, S. (2012) “Field distribution and activity of chlorinated solvents degrading bacteria by combining CARD-FISH and real time PCR”, New Biotechnology, 30(1), 23-32.

Masaaki M., Shinji K., Mitsuru H., Kazufumi T., Steve Branda., Roberto Kolter., Shigenori Kanaya., (2006), “Biofilm formation by a Bacillus subtilis strain that produces γ-polyglutamate”, Microbiology 152, 2081-2807.

Mohammad F. A., Ian P.G.M, Sebastian B, Alfred M.S., Lewis S.,(2010), “Comparison of lactate, formate, and propionate as hydrogen donors for the reductive dehalogenation of trichloroethene in a continuous-flow column”, Journal of Contaminant Hydrology, Issues 1–4, 1 April 2010, Pages 77–92.

Nubel, U., Engelen, B., Felske, A., Snaidr, J., Wieshuber, A., Amann, R.I., Ludwig, W. and Backhaus, H., (1996), “Sequence heterogeneities of genes encoding 16S rRNAs in Paenibacillus polymyxa detected by temperature gradient gel electrophoresis”, Journal of Bacteriology 178: 5636-5643.

O’Carroll, D., Sleep, B., Krol, M., Boparai, H. and Kocur, C., (2013), “Nanoscale zero valent iron and bimetallic particles for contaminated site remediation”, Advances in Water Resources, 51, 104-122.

Park B.G., Kang H.S., Lee W, Kim J.S., Son T.I.., (2013), “Reinforcement of pH-responsive gpoly(glutamic acid)/chitosan hydrogel for orally administrable colon-targeted drug delivery”, J Appl Polym Sci 2013;127(1):832e6.

Pant, P., Pant, S., (2010), “A review: advances in microbial remediation of trichloroethylene (TCE) ”, Res. J. Environ. Sci. — China 22, 116–126.

Popat ,S.C., Zhao ,K., Deshusses ,M.A.,(2012), “Bioaugmentation of an anaerobic biotrickling filter for enhanced conversion of trichloroethene to ethene”, Chemical Engineering Journal, 15 February 2012, Pages 98–103.

Ritalahti, K.M., Amos, B.K., Sung, Y.,Wu, Q.Z., Koenigsberg, S.S. and Löffler, F.E., (2006), “Quantitative PCR targeting 16S rRNA and reductive dehalogenase genes simultaneously monitors multiple Dehalococcoides strains”, Applied and Environmental Microbiology 72:2765-2774.

Su, C., Puls, R.W., Krug, T.A., O'Hara, S.K., Quinn, J.W and Ruiz, N.E. (2012) “A two and half-year-performance evaluation of a field test on treatment of source zone tetrachloroethene and its chlorinated daughter products using emulsified zero valent iron nanoparticles”, Water Research, 46(16), 5071-5084.

Shih, I. I., and Van, Y. T., (2001). “The production of poly-(γ-glutamic acid) from microorganism and its various applications”, Bioresource Technology, 79, 207-225.

Tiehm A., Kohnagel I., Neis U., (2001), “Removal of chlorinated pollutants by a combination of ultrasound and biodegradation”, Water Science & Technology Vol 43 No 2 p297–303 © IWA Publishing 2001.

U.S Environmental Protection Agency, USEPA. (1999), “Monitored Natural Attenuation of Chlorinated Solvents”, 600.

U.S. Environmental Protection Agency (EPA), (2000), “Engineerd Approaches to In Situ Bioremediation of Chlorinated Solvents：Fundamentals and Field Applications ”, EPA 542-R-00-008.

U.S. Environmental Protection Agency (EPA), (2012), “A Citizen’s Guide to Soil Vapor Extraction and Air Sparging ”, EPA 542-F-12-018.

Xiu, Z. M., Gregory, K. B., Lowry, G. V. and Alvarez, P. J., (2010), “Effect of Bare and Coated Nanoscale Zerovalent Iron on tceA and vcrA Gene Expression in Dehalococcoides spp”, Environmental science & technology, 44(19), 7647-7651.

Yeh, C. H., Lin, C. W. and Wu, C. H., (2010), “A permeable reactive barrier for the bioremediation of BTEX-contaminated groundwater:Microbial community distribution and removal efficiencies”, Journal of hazardous materials, 178(1), 74-80.

Yoshida, H., Klinkhammer, K., Matsusaki, M., Möller, M., Doris, K., Akashi, M., (2009), “Disulfide-Crosslinked Electrospun Poly (γ-glutamic acid) Nonwovens as Reduction-Responsive Scaffolds”,Macromolecular Bioscience, Issue 6, pages 568–574.