کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1696684 1519142 2006 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Adsorption and antibacterial effect of copper-exchanged montmorillonite on Escherichia coli K88
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
پیش نمایش صفحه اول مقاله
Adsorption and antibacterial effect of copper-exchanged montmorillonite on Escherichia coli K88
چکیده انگلیسی

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 antibacterial activity on Escherichia coli K88. AAM, Na-MMT and Ca-MMT showed some ability to reduce bacterial plate counts by 37.4%, 13.4% and 14.2%, respectively. Exchanging the montmorillonite with Cu2+ enhanced the antibacterial activity. The Cu*AAM, Cu*Na-MMT and Cu*Ca-MMT reduced the bacterial plate counts by 98.6%, 97.5% and 95.6%. Attempts were made to study the desorption of Cu2+ by washing with sterile physiological saline solution for 24 h. The washing solutions did not show a significant reduction of the bacterial counts, while the washed Cu-MMT retained their full antibacterial activity. Results from time-depending studies showed that the reduction of the bacterial counts by Cu-MMT increased during 24 h. The ranking of antibacterial activity of the three Cu-MMT was as Cu*AAM > Cu*Na-MMT > Cu*Ca-MMT. E. coli thrived optimally in a pH range from 5 to 7. Beyond this range, the bacterial counts decreased as the pH reduced the viability of the bacteria. The ranking of antibacterial activity of Cu-MMT was not affected by pH. The mechanism by which bacterial counts are reduced may involve the enhanced affinity of Cu-MMT for E. coli K88 and the antibacterial activity of Cu2+.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Clay Science - Volume 31, Issues 3–4, March 2006, Pages 180–184
نویسندگان
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