Document Type : Research Article
Author
University of Kerbala, College of Science, Department of Physics
Abstract
The aim of this study is to inhibit the activity of efficient of Escherichia coli suspended in water using helium plasma jets operating at excitation frequency of 12 kHz of atmospheric pressure. These bacteria are widespread in the environment, especially in drinking water, and their pathogenic effects are extremely harmful. 50 mL drinking water contaminated with E. coli was exposed to plasma plume, the treatment time ranged as (5, 10, 15, 20 to 25) minutes. Reactive chemical species such as excited state molecules, ionic compounds and radicals produced in plasma with water detected using the method of photoemission spectroscopy. The bacterial count was reduced from 〖235×10〗^10 CFU⁄mL to 〖42×10〗^8 CFU⁄mL within 5 minutes. The number of bacteria observed a continuous decrease in every five minutes treatments until the number of bacteria per minute reaches 〖4×10〗^2 CFU⁄(mL after 25 minute). Moreover, the reduction in turbidity of the water sample containing E. coli bacteria is clear, as illustrated in two samples. Sample 1 goes from 1.87 NTU control to 0.09 NTU when the period of treatment is 25 minutes, and sample 2 goes from 2.70 NTU control to 0.9 NTU in the same treatment period. An SRE-APHPJ is a promising technique for sterilizing bacteria (E. coli) suspended in water.
Keywords
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