Adsorption of Aeromonas hydrophila by copper-bearing montmorillonite clays

作者：Xia Mei Sheng; Hu Cai Hong; Xu Yong; Zhao Wen Yan

来源：Journal of Inorganic Materials, 2007, 22(4): 652-656.

• montmorillonite
• copper-bearing montmorillonite
• aeromonas hydrophila
• adsorption

Calcium montmorillonite (Ca-MMT), sodium. montmorillonite (Na-MMT) and acid-activated montmorillonite (AAM), and their Cu2+-exchanged montmorillonites (Cu-MMT), Cu* Ca-MMT, Cu*Na-MMT and Cu*AAM, were used to study the adsorptive activity on Aeromonas hydrophila. The Zeta potentials of MMTs and A.hydrophila are all decreased with increasing pH, and those of Cu-MMTs are increased with increasing pH and transformed from the negative to positive value when pH=4-6. AAM, Na-MMT and Ca-MMT show some ability to reduce bacterial plate counts by 36.5%, 20.1% and 14.3%, respectively. The Cu*AAM, Cu*Na-MMT and Cu*Ca-MMT reduce the bacterial plate counts by 99.6%, 93.1% and 87.4%. The extent of bacterial adsorption onto MMTs is decreased with increasing pH. However, the bacterial adsorption onto Cu-MMTs is decreased with increasing pH and increased with increasing pH when pH>5.0. The study of desorption of Cu2+ by washing with physiological saline for 24h reveals that the washing solutions don't show a significant reduction of the bacterial counts, while the washed Cu-MMTs retain their full antibacterial activity. The mechanism by which bacterial counts are reduced may involve the enhanced affinity of Cu-MMT for Aeromonas hydrophila and the antibacterial activity of Cu2+.

• 出版日期2007-7
• 单位浙江大学