摘要
针对室内细菌气溶胶传播导致的空气生物安全性问题,以大肠杆菌和枯草芽孢杆菌为模式菌种,低温等离子体作为灭菌手段,对细菌气溶胶进行灭活实验研究.探究了输入电压、载气流速和初始浓度对灭活效率的影响,发射光谱、电子顺磁共振波谱及生物表征结果揭示了低温等离子体产生的活性物种(主要包括1 O_(2)、O_(2)-和·OH),在灭活过程中破坏了细菌的细胞膜,导致其蛋白质泄露,脂质和核酸被分解,最终导致细菌完全失活.而增加输入电压和减小流速可提高灭活效率,较高的初始浓度也有利于细菌气溶胶的灭活.两类细菌对低温等离子体的抗性为:枯草芽孢杆菌>大肠杆菌,而枯草芽孢杆菌和大肠杆菌的灭活速率常数(k)为0.0038和0.0043L/J,能量效率为0.027和0.021(kW·h)/m^(3),结果证明低温等离子体灭杀革兰氏阴性菌更具优势.
To address the issue of indoor bacterial aerosol transmission and ensure air biosafety,an experiment was conducted utilizing E.coli and Bacillus subtilis.as model strains,with non-thermal plasma employed as a means of sterilization.The study investigated the impact of input voltage,carrier gas flow rate,and initial concentration on the efficiency of bacterial aerosol inactivation.Analysis of OES,EPR,and biological characterization results revealed that reactive species(primarily including 1 O_(2),O_(2)-,·OH)generated by non-thermal plasma during the inactivation process disrupted the bacteria's cell membrane leading to protein leakage,breakdown of lipids and nucleic acids ultimately resulting in complete bacterial inactivation.Increasing input voltage while decreasing flow rate could improve inactivation efficiency.However,when the initial concentration increased to a threshold,the improvement on the inactivation efficiency was negligible.The resistance of the two bacteria aerosols inactivated by non-thermal plasma was:Bacillus subtilis>E.coli.Specifically,Bacillus subtilis demonstrated an inactivation rate constant(k)of 0.0038L/J along with an energy efficiency value of 0.027(kW·h)/m^(3);whereas for E.coli these values were measured at 0.0043L/J and 0.021(kW·h)/m^(3) respectively indicating that non-thermal plasma was more effective against gram-negative bacteria such as E.coli.
作者
焦阳
吉硕
于欣
王赫
党小庆
张宇飞
JIAO Yang;JI Shuo;YU Xin;WANG He;DANG Xiao-qing;ZHANG Yu-fei(School of Environment&Municipal Engineering,Xi’an University of Architecture&Technology,Xi’an 710055,China;Key Laboratory of Northwest Water Resource,Environment and Ecology,Ministry of Education,Key Laboratory of Environmental Engineering of Shaanxi Province,Xi’an 710055,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2024年第7期3615-3624,共10页
China Environmental Science
基金
国家重点研发计划项目(2017YFC0212204)
陕西省重点研发计划项目(2018ZDCXL-SF-02-04)
国家自然科学基金资助项目(52370119)。
关键词
低温等离子体
细菌
生物气溶胶
灭活机制
活性物种
non-thermal plasma
bacteria
bioaerosol
inactivation mechanism
reactive species
