抗生素近年來逐漸成為潛在危害環境衛生汙染源之一，台灣持續進口大量抗生素作為醫療及動物用藥，其中乙醯胺類抗生素(β-lactam antibiotics)為進口量最大的抗生素，除使用於醫療用途外，該類抗生素亦使用於畜牧業以達到促進牲畜生長速率及提高肌肉量等目的。另外，微量元素在動物及植物營養上扮演重要角色，是許多新陳代謝的重要元素。因此在飼料中也會加入微量金屬元素以達到平衡動物生長所需的元素，然而，抗生素在經動物食用後，會有部分以原形態經由糞尿進入環境中，對環境產生危害，並有文獻指出乙醯胺類抗生素常與金屬元素產生螯合作用。本研究挑選在乙醯胺類抗生素中常用的兩種化合物阿比西林(ampicillin)及阿莫西林(amoxicillin)做為目標分析物，目的在於1.設計批次試驗探討不同因子對於目標化合物降解速率的影響，並計算反應常數及利用迴歸分析探討其相關性；2.探討金屬離子在此反應系統中所扮演的角色以及分析在反應過程中是否有產物產生。
本研究係利用串聯式液相層析質譜儀及可見光-紫外光分光光度計作為分析儀器，由批次實驗結果得知，乙醯胺類抗生素能與銅離子反應降解，當反應中存在越高濃度的銅離子時，會使反應速率加快。在鹼性環境下，反應較酸性及中性環境快，假如同時存在鹼土金屬(如鈣鎂離子)，對阿比西林而言，鈣鎂離子只會抑制反應初速，若改變其添加濃度時，並未有明顯的影響，反觀，對於阿莫西林，除反應初速外，鈣鎂離子則會對反應速率有明顯的影響，添加濃度與反應速率呈現負相關。
本研究亦針對銅離子在與乙醯胺類抗生素反應後型態的變化進行探討，結果顯示，二價銅離子與此兩種目標抗生素反應後，透過加入金屬螯合劑測試反應起始與經過20小時後，利用紫外光可見光分光光度計分析可發現溶液中原本存在的二價銅離子被還原成一價亞銅離子，顯示銅離子在此反應中為氧化劑。
根據串聯式液相層析質譜儀定性分析結果推論，在乙醯胺類抗生素與金屬離子反應過程中會有產物產生，然而目前所得到的結果無法完整將反應機制結果呈現，但未來可利用本研究結果，加入更完善的實驗佐證以達到定性分析的目的。
乙醯胺類抗生素雖在生物毒性上屬於慢毒性化合物，但至今對於此類抗生素的調查依舊略顯不足，對於環境上的危害性還尚需有更完整的研究，未來可針對此領域做更深入的研究探討。

Antibiotics recently are considered as potential trace contaminants in the environment. Taiwan continues to import large quantities of antibiotics for medical and agricultural purposes. β-lactam antibiotics account for up to 20 percent of total veterinary drugs usage in Taiwan for past ten years. In addition to the medical treatment, this group of antibiotics also applies to livestock to promote their growth. Many research indicated that the antibiotics would be released to the environment via urine and feces with unchanged parent compounds or metabolites. Metal ions are also common feed additives as trace essential elements in addition to the antibiotics.
In previous studies, many authors have reported that β-lactam antibiotics were widely studied in the presence of various metal ions. The objectives of this research are 1. designing batch reactions to examine the degradation of two β-lactam antibiotics (ampicillin and amoxicillin) under different conditions and calculating the kinetic constants; 2. using UV-Vis spectrophotometer and LC-MSMS to elucidate the product generation and reaction mechanism.
According to the batch reaction results, in the presence of high Cu2+ concentration under alkaline condition, the reaction is much faster than other conditions. Ca2+ ion and Mg2+ ion are founded that if they coexist in the solution, the reaction will be inhibited. The inhibitory effect was more pronounced in the amoxicillin-Cu2+ system.
According to the bathocuproine complexation set up, it was confirmed that Cu2+ ion is reduced to Cu+ ion both in the ampicillin-Cu2+ and amoxicillin-Cu2+ Systems, suggesting the oxidation leads to the degradation of ampicillin and amoxicillin. There are some product peaks observed in the LC chromatograms. However, the details of the product structures and transformation pathway are not proposed in this study. Further qualitative studies are suggested to further elucidate β-lactam antibiotic degradation mechanism and pathway in order to better understand the risk they may pose to human health and ecosystem.

Alcock, R. E., et al. (1999). "Assessment of organic contanhnant fate in waste water treatment plants I: Selected compounds and physicochemical properties." Chemosphere 38(10): 2247-2262.

Andreozzi, R., et al. (2005). "Antibiotic removal from wastewaters: The ozonation of amoxicillin." Journal of Hazardous Materials 122(3): 243-250.

Andreozzi, R., et al. (2004). "Antibiotics in the environment:  Occurrence in Italian STPs, fate, and preliminary assessment on algal toxicity of amoxicillin." Environmental Science & Technology 38(24): 6832-6838.

Biehl, M. L. B., W.J. (1987). "Chemical contaminants: their metabolism and their residues." Journal of Food Protect 50(12): 1058-1073.

Brown, L. C. and P. M. Berthouex (2002). Statistics for Environmental Engineers, Second Edition.

Campos, C., et al. (2009). "Evaluation of the copper(II) reduction assay using bathocuproinedisulfonic acid disodium salt for the total antioxidant capacity assessment: The CUPRAC–BCS assay." Analytical Biochemistry 392(1): 37-44.

Castiglioni, S., et al. (2005). "Removal of pharmaceuticals in sewage treatment plants in Italy." Environmental Science & Technology 40(1): 357-363.

Cha, J. M., et al. (2006). "Trace determination of β-lactam antibiotics in surface water and urban wastewater using liquid chromatography combined with electrospray tandem mass spectrometry." Journal of Chromatography A 1115(1–2): 46-57.

Christian, T., et al. (2003). "Determination of antibiotic residues in manure, soil, and surface waters." Acta hydrochimica et hydrobiologica 31(1): 36-44.

Crane, M., et al. (2006). "Chronic aquatic environmental risks from exposure to human pharmaceuticals." Science of The Total Environment 367(1): 23-41.

Deshpande, A., et al. (2004). "Degradation of β-lactam antibiotics." Current Science 87(12): 1684-1695.

Esplugas, S., et al. (2007). "Ozonation and advanced oxidation technologies to remove endocrine disrupting chemicals (EDCs) and pharmaceuticals and personal care products (PPCPs) in water effluents." Journal of Hazardous Materials 149(3): 631-642.

Fazakerley, G. V. and G. E. Jackson (1975). "Metal ion coordination by some penicillin and cephalosporin antibiotics." Journal of Inorganic and Nuclear Chemistry 37(11): 2371-2375.

Fernández-González, A., et al. (2005). "Insights into the reaction of β-lactam antibiotics with copper(II) ions in aqueous and micellar media: Kinetic and spectrometric studies." Analytical Biochemistry 341(1): 113-121.

Ghauch, A., et al. (2009). "Antibiotic removal from water: Elimination of amoxicillin and ampicillin by microscale and nanoscale iron particles." Environmental Pollution 157(5): 1626-1635.

Gozlan, I., et al. (2013). "Amoxicillin-degradation products formed under controlled environmental conditions: Identification and determination in the aquatic environment." Chemosphere 91(7): 985-992.

Granelli, K. and C. Branzell (2007). "Rapid multi-residue screening of antibiotics in muscle and kidney by liquid chromatography-electrospray ionization–tandem mass spectrometry." Analytica Chimica Acta 586(1–2): 289-295.

Hölzel, C. S., et al. (2012). "Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance." Environmental Research 113(0): 21-27.

Kümmerer, K. (2009). "Antibiotics in the aquatic environment – A review – Part I." Chemosphere 75(4): 417-434.

Kan, C. A. and G. A. L. Meijer (2007). "The risk of contamination of food with toxic substances present in animal feed." Animal Feed Science and Technology 133(1–2): 84-108.

Kannan, K., et al. (2006). "Comparison of trace element concentrations in livers of diseased, emaciated and non-diseased southern sea otters from the California coast." Chemosphere 65(11): 2160-2167.

Kolpin, D. W., et al. (2002). "Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams, 1999−2000:  A National Reconnaissance." Environmental Science & Technology 36(6): 1202-1211.

Kotra, L. P. and S. Mobashery (1998). "β-Lactam antibiotics, β-lactamases and bacterial resistance." Bulletin de l'Institut Pasteur 96(3): 139-150.

Kozłowski, H., et al. (2005). "Chemical and biological aspects of Cu2+ interactions with peptides and aminoglycosides." Coordination Chemistry Reviews 249(21–22): 2323-2334.

Lützhøft, H. C. H., et al. (1999). "Algal toxicity of antibacterial agents applied in danish fish farming." Archives of Environmental Contamination and Toxicology 36(1): 1-6.

Li, D., et al. (2008). "Determination of penicillin G and its degradation products in a penicillin production wastewater treatment plant and the receiving river." Water Research 42(1–2): 307-317.

Lin, A. Y.-C., et al. (2008). "Pharmaceutical contamination in residential, industrial, and agricultural waste streams: Risk to aqueous environments in Taiwan." Chemosphere 74(1): 131-141.

Lindberg, R., et al. (2004). "Determination of antibiotic substances in hospital sewage water using solid phase extraction and liquid chromatography/mass spectrometry and group analogue internal standards." Chemosphere 57(10): 1479-1488.

Lindberg, R. H., et al. (2005). "Screening of human antibiotic substances and determination of weekly mass flows in five sewage treatment plants in Sweden." Environmental Science & Technology 39(10): 3421-3429.

Malouin, F. and L. Bryan (1986). "Modification of penicillin-binding proteins as mechanisms of beta-lactam resistance." Antimicrobial agents and chemotherapy 30(1): 1.

Martı́nez, J. H., et al. (1999). "β-Lactam degradation catalysed by Cd2+ ion in methanol." International Journal of Biological Macromolecules 25(4): 337-343.

Messerle, B. A., et al. (1990). "Three-dimensional structure of human [113Cd7]metallothionein-2 in solution determined by nuclear magnetic resonance spectroscopy." Journal of Molecular Biology 214(3): 765-779.

Michael, I., et al. (2013). "Urban wastewater treatment plants as hotspots for the release of antibiotics in the environment: A review." Water Research 47(3): 957-995.

Mitchell, S. M., et al. (2014). "pH and temperature effects on the hydrolysis of three β-lactam antibiotics: Ampicillin, cefalotin and cefoxitin." Science of The Total Environment 466–467(0): 547-555.

Motoyama, M., et al. (2011). "Residues of pharmaceutical products in recycled organic manure produced from sewage sludge and solid waste from livestock and relationship to their fermentation level." Chemosphere 84(4): 432-438.

Msagati, T. A. M. and M. M. Nindi (2007). "Determination of β-lactam residues in foodstuffs of animal origin using supported liquid membrane extraction and liquid chromatography–mass spectrometry." Food Chemistry 100(2): 836-844.

Mukherjee, G. and T. Ghosh (1995). "Metal ion interaction with penicillins— part VII: Mixed-ligand complex formation of cobalt(II), nickel(II), copper(II), and zinc(II) with amplicillin and nucleic bases." Journal of Inorganic Biochemistry 59(4): 827-833.

Nägele, E. and R. Moritz (2005). "Structure elucidation of degradation products of the antibiotic amoxicillin with ion trap MSn and accurate mass determination by ESI TOF." Journal of the American Society for Mass Spectrometry 16(10): 1670-1676.

Nakada, N., et al. (2007). "Removal of selected pharmaceuticals and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs) during sand filtration and ozonation at a municipal sewage treatment plant." Water Research 41(19): 4373-4382.

Navalon, S., et al. (2008). "Reaction of chlorine dioxide with emergent water pollutants: Product study of the reaction of three β-lactam antibiotics with ClO2." Water Research 42(8–9): 1935-1942.

Navarro, P. G., et al. (2003). "Penicillin degradation catalysed by Zn(II) ions in methanol." International Journal of Biological Macromolecules 33(4–5): 159-166.

Nicholson, F. A., et al. (1999). "Heavy metal contents of livestock feeds and animal manures in England and Wales." Bioresource Technology 70(1): 23-31.

Novo, A., et al. (2013). "Antibiotic resistance, antimicrobial residues and bacterial community composition in urban wastewater." Water Research 47(5): 1875-1887.

Ohmori, T., et al. (2011). "Simultaneous determination of eight β-lactam antibiotics in human serum by liquid chromatography–tandem mass spectrometry." Journal of Chromatography B 879(15–16): 1038-1042.

Okerman, L., et al. (2007). "Stability of frozen stock solutions of beta-lactam antibiotics, cephalosporins, tetracyclines and quinolones used in antibiotic residue screening and antibiotic susceptibility testing." Analytica Chimica Acta 586(1–2): 284-288.

Olson, E. J. and P. Bühlmann (2011). "Getting More out of a Job Plot: Determination of Reactant to Product Stoichiometry in Cases of Displacement Reactions and n:n Complex Formation." The Journal of Organic Chemistry 76(20): 8406-8412.

Pugh, D. M. (2002). "The EU precautionary bans of animal feed additive antibiotics." Toxicology Letters 128(1–3): 35-44.

Rapson, H. D. C. and A. E. Bird (1963). "Ionisation constants of some penicillins and their alkaline nad penicillinase hydrolysis products." Journal of Pharmacy and Pharmacology 15(S1): 222T-231T.

Riediker, S., et al. (2004). "Cold-temperature stability of five β-lactam antibiotics in bovine milk and milk extracts prepared for liquid chromatography–electrospray ionization tandem mass spectrometry analysis." Journal of Chromatography A 1054(1–2): 359-363.

Rozas, O., et al. (2010). "Experimental design of Fenton and photo-Fenton reactions for the treatment of ampicillin solutions." Journal of Hazardous Materials 177(1–3): 1025-1030.

Sabry, S. A., et al. (1997). "Metal tolerance and antibiotic resistance patterns of a bacterial population isolated from sea water." Journal of Applied Microbiology 82(2): 245-252.

Salem, H. (2004). "Selective spectrophotometric determination of phenolic β-lactam antibiotics in pure forms and in their pharmaceutical formulations." Analytica Chimica Acta 515(2): 333-341.

Salem, H. and G. A. Saleh (2002). "Selective spectrophotometric determination of phenolic β-lactam antibiotics." Journal of Pharmaceutical and Biomedical Analysis 28(6): 1205-1213.

Sarmah, A. K., et al. (2006). "A global perspective on the use, sales, exposure pathways, occurrence, fate and effects of veterinary antibiotics (VAs) in the environment." Chemosphere 65(5): 725-759.

Sharma, V. K., et al. (2013). "Oxidation of β-lactam antibiotics by ferrate(VI)." Chemical Engineering Journal 221(0): 446-451.

Smith, J., et al. (1967). "The spectrophotometric determination of ampicillin." Analyst 92(1093): 247-252.

Sridhara Chary, N., et al. (2008). "Assessing risk of heavy metals from consuming food grown on sewage irrigated soils and food chain transfer." Ecotoxicology and Environmental Safety 69(3): 513-524.

Tolls, J. (2001). "Sorption of veterinary pharmaceuticals in soils:  A review." Environmental Science & Technology 35(17): 3397-3406.

Trovó, A. G., et al. (2011). "Degradation of the antibiotic amoxicillin by photo-Fenton process – chemical and toxicological assessment." Water Research 45(3): 1394-1402.

Watkinson, A. J., et al. (2007). "Removal of antibiotics in conventional and advanced wastewater treatment: Implications for environmental discharge and wastewater recycling." Water Research 41(18): 4164-4176.

Zhou, L.-J., et al. (2013). "Excretion masses and environmental occurrence of antibiotics in typical swine and dairy cattle farms in China." Science of The Total Environment 444(0): 183-195.

林正芳, et al. (2008). 新興汙染物(抗生素與止痛藥)於特定汙染源環境之流佈.