- 學位論文
大氣重金屬成分與細菌抗生素抗藥性之影響探討
Evaluation of atmospheric heavy metal and bacteria antibiotic resistance
摘要
本研究透過高量採樣法(NIEA A102.13A)進行台中地區PM2.5與PM10之採樣，並同時進行生物氣膠的採樣，後續分析大氣氣膠成分與生物氣膠的菌種鑑定與抗藥性特性。並以水溶性金屬鋅與金屬銅溶液，以大氣PM2.5分析濃度100倍、200倍與400倍濃度暴露蠟樣芽孢桿菌(Bacillus cereus)，觀察抗藥特性之變化，也使用紙錠擴散法配合不同濃度之重金屬溶液觀察細菌抑制圈之變化。 研究結果顯示，大氣中採樣之生物氣膠，細菌以巨大芽孢桿菌(Bacillus megaterium)為優勢菌種，真菌以尖孢枝孢菌(Cladosporium oxysporum) 為優勢菌種，分析菌種中有19.2%具抗生素抗藥性，其中又以Ampicillin (43.2%) 與penicillin G(40.5%) 為最多細菌具有抗藥性之抗生素。本研究礙於無法直接取得BD Phoenix詳細最低抑菌濃度(minimum inhibitory concentration, MIC)值，因此選擇以直接重金屬水溶液或紙錠擴散法暴露，以取得Bacillus cereus抗藥性MIC之變化結果。在暴露重金屬水溶液400倍濃度時，菌落形成數僅為對照組之5%，暴露濃度與菌落數具統計顯著差異(P<0.05)；在紙錠試驗中發現Ampicillin與Cefoxitin在暴露於濃度100倍與200倍之金屬水溶液，其抑制圈相較於對照組皆有增加。因此，大氣成分中之水溶性銅、鋅成份，對同為大氣中採集而得的抗藥性細菌，對其抗生素抗藥特性有顯著增強影響。
並列摘要
In this study, the TISCH high volume sampler (Taiwan WPA NIEA A102.13A) was applied to collect PM2.5 and PM10 in the Taichung city, and the bioaerosol was also sampled. The atmospheric aerosol components, the bacterial species identification and antibiotic-resistance analysis of the bacteria were subsequently analyzed. The results of the study showed that Bacillus megaterium was the dominant species of bacteria and Cladosporium oxysporum was the dominant species of fungi in the atmosphere. 19.2% of the analyzed species were antibiotic-resistance, among which Ampicillin (43.2%) and penicillin G (40.5%) were the most bacteria resistant antibiotics. The study due to the fact of lacking of the minimum inhibitory concentration (MIC) of Bacillus cereus from BD Phoenix, the direct water-soluble metal solution broth and disk-diffusion with different concentrations of copper and zinc solutions were used to test the MIC of Ampicillin and Cefoxitin. The sampled Bacillus cereus was then exposed to water soluble metal zinc and copper solutions with desired concentrations of 100X, 200X and 400X. The number of colonies was only 5% of the control group when exposed to test concentration of 400X, and exhibited statistical significance (p <0.05) . In the disk-diffusion, it was found that when exposed to Ampicillin or Cefoxitin, the Bacillus cereus increased the MICs at 100X and 200X concentrations of water-soluble metal zinc and copper solutions when compared to the control group. The water-soluble metal zinc and copper compositions from ambient air were found to enhance the antibiotic-resistant of sampled bactria.