Effect of Plasma-Activated Solution Treatment on Cell Biology of <i>Staphylococcus aureus</i> and Quality of Fresh Lettuces
Jianying Zhao,
Jing Qian,
Hong Zhuang,
Ji Luo,
Mingming Huang,
Wenjing Yan,
Jianhao Zhang
Affiliations
Jianying Zhao
National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
Jing Qian
National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
Hong Zhuang
Quality and Safety Assessment Research Unit, U.S. National Poultry Research Center, USDA-ARS, 950 College Station Road, Athens, GA 30605, USA
Ji Luo
College of Life Science, Anhui Normal University, Wuhu 241000, China
Mingming Huang
College of Food Science and Engineering, Shandong Agricultural University, Tai’an 271018, China
Wenjing Yan
National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
Jianhao Zhang
National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
This study aimed to investigate effects of plasma-activated solution (PAS) on the cell biology of Staphylococcus aureus and qualities of fresh lettuce leaves. PAS was prepared by dielectric barrier discharge plasma and incubated with S. aureus for 10–30 min or with lettuces for 10 min. Effects on cell biology were evaluated with microscopic images, cell integrity, and chemical modification of cellular components. Effects on lettuce quality were estimated with the viable microbial counts, color, contents of vitamin C and chlorophyll, and surface integrity. PAS reduced S. aureus population by 4.95-log and resulted in increased cell membrane leakage. It also resulted in increased contents of reactive oxygen species in cells, C=O bonds in peptidoglycan, and 8-hydroxydeoxyguanosine content in cellular DNA, and reduced ratios of unsaturated/saturated fatty acids in the cell membrane. PAS treatment reduced bacterial load on fresh lettuce and had no negative effects on the quality. Data suggest that PAS can be used for the disinfection of ready-to-eat fresh vegetables.
