Non-thermal plasma-activated water inactivation of food-borne pathogen on fresh produce.
Non-thermal plasma has been widely considered to be an effective method for decontamination of foods. Recently, numerous studies report that plasma-activated water (PAW) also has outstanding antibacterial ability. This study presents the first report on the potential of PAW for the inactivation of Staphylococcus aureus (S. aureus) inoculated on strawberries. PAW treatments achieved a reduction of S. aureus ranging from 1.6 to 2.3 log at day-0 storage, while 1.7 to 3.4 log at day-4 storage. The inactivation efficiency depended on the plasma-activated time for PAW generation and PAW-treated time of strawberries inoculated with S. aureus. LIVE/DEAD staining and scanning electron microscopy results confirm that PAW could damage the bacterial cell wall. Moreover, optical emission spectra and oxidation reduction potential results demonstrate the inactivation is mainly attributed to oxidative stress induced by reactive oxygen species in PAW. In addition, no significant change was found in color, firmness and pH of the PAW treated strawberries. Thus, PAW can be a promising alternative to traditional sanitizers applied in the fresh produce industry.
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China.
Ruonan
R
Ma
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China.
Guomin
G
Wang
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China.
Ying
Y
Tian
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China.
Kaile
K
Wang
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China; College of Engineering, Peking University, Beijing 100871, PR China. Electronic address: zhangjue@pku.edu.cn.
Jue
J
Zhang
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China; College of Engineering, Peking University, Beijing 100871, PR China.
Jing
J
Fang
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D058491:Bacterial Load; D015169:Colony Count, Microbial; D003116:Color; D005516:Food Microbiology / Q000379:methods*; D061353:Food Storage; D031985:Fragaria / Q000382:microbiology*; D005658:Fungi / Q000254:growth & development; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D058626:Plasma Gases / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects*; D014867:Water / Q000737:chemistry* / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D058626:Plasma Gases; D017382:Reactive Oxygen Species; D014867:Water
Inactivation; Non-thermal plasma-activated water; Reactive oxygen species; Staphylococcus aureus; Strawberries