溫泉對細菌生物膜生成之影響

Effect of Hot Spring on Formation of Bacterial Biofilm

本研究採EHEC O4大腸桿菌作為溫泉水質污染之追蹤參考菌種。實驗將EHEC O4培養於12孔之培養皿，並以3 mL的溫泉水培養作為實驗組，包括：北投溫泉、泰安溫泉、關子嶺溫泉、寶來溫泉、四重溪溫泉、知本溫泉及安通溫泉。另實驗以同體積之NaCl培養溶液作為對照組。研究以細菌生物膜作為污染指標的檢測法（Crystal Violet染色法；590 nm），以評估溫泉對細菌生長之影響。結果發現，培養第1天後，對照組細菌生物膜檢測呈現陽性檢出情形。相對之，實驗組之溫泉全數呈現抑制細菌生物膜生成的作用。實驗培養第3天後，各組吸光值檢測結果，分別為：對照組（0.63）、北投（0.17）、泰安（0.27）、關子嶺（0.27）、寶來（0.28）、四重溪（0.25）、知本溫泉（0.29）及安通（0.44）；第7天時，分別為：對照組（0.78）、北投（0.18）、泰安（1.66）、關子嶺（0.36）、寶來（1.04）、四重溪（0.92）、知本溫泉（0.48）及安通（0.75）。綜合實驗結果顯示，溫泉水於EHEC O4大腸桿菌培養初期（1-3天），具更明顯抑制細菌生物膜生長的作用，然而，隨著培養天數的增加，部份溫泉反而呈現促進細菌生物膜生長之作用，其詳細之作用機制則待更多研究證實。

In this study, the E. coli strains （EHEC O4） was used as an indicator of hot spring pollution. The EHEC O4 was added in the 12-welled petri dish. The control group contained 3 mL of NaCl solution whereas Beitou, Taian, Guanziling, Polaris, Szuchung, Antong, and Chihpen are added respectively in other wells as experimental groups. On the 3rd and 7th days, impact on growth of the bacteria was evaluated by detecting bacterial biofilms formed in each well by using Crystal Violet assay when the spectrophotometric absorbance at 590 nm. However, the result of this study showed that the bacterial biofilm in the NaCl solution started growing in the first day. Compared with NaCl solution, growth of bacterial biofilm is inhibited in other hot spring solutions. On the 3rd day, absorbance values are detected as: Beitou （0.17）, Taian （0.27）, guanziling （0.27）, Polaris （0.28）, ssuchungchi （0.25）, hotspring （0.29）, Anton （0.44） and NaCl （0.63）. However on the 7th day, absorbance values are detected as: Taian （1.66）, Polaris （1.04） and ssuchungchi （0.92）, which were all higher than the control group NaCl （0.78）, while the hot springs Beitou （0.18）, guanziling （0.36）, Chihpen （0.48） still showed inhibited effects. On the other hand, absorbance value of Antun （0.75） hot spring was similar to the control group （0.78）. The result indicated that hot springs in most areas in Taiwan had effect on inhibition of growth of bacterial biofilm in early period, but there were still few hot springs which promoted growth of bacterial biofilm in later phase. As a result, further researches should be done to verify the mechanism of the hot springs.