Infection and Drug Resistance (Apr 2023)
The Anti-Biofilm Activity and Mechanism of Apigenin-7-O-Glucoside Against Staphylococcus aureus and Escherichia coli
Abstract
Ze-Jun Pei,1– 3,* Chengcheng Li,1,3,* Wenna Dai,4 Zaixiang Lou,3 Xin Sun,1,2 Hongxin Wang,3 Azmat Ali Khan,5 Chunpeng Wan5 1State Key Laboratory of Dairy Biotechnology, Technology Center of Bright Dairy and Food Company Ltd, Shanghai, People’s Republic of China; 2Department of Pharmacy, Wuxi No.2 People’s Hospital, Nanjing Medical University, Wuxi, 214002, People’s Republic of China; 3State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, People’s Republic of China; 4School of Food Science, Wuhu Institute of Technology, Wuhu, 241006, People’s Republic of China; 5Research Center of Tea and Tea Culture, College of Agronomy, Jiangxi Agricultural University, Nanchang, 330045, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zaixiang Lou, Email [email protected]: This study aimed to examine the anti-biofilm activity and mechanism of gallic acid (GA), kaempferol-7-O-glucoside (K7G) and apigenin-7-O-glucoside (A7G) against Staphylococcus aureus and Escherichia coli.Methods: The antibacterial activity of the natural compounds was determined by serial dilution method. The inhibitory activity of natural compounds on biofilms was determined by crystal violet staining method. The effects and mechanisms of natural compounds on bacterial biofilms were analyzed by atomic force microscopy.Results: In our study, compared with GA and K7G, A7G was found to exhibit the strongest anti-biofilm and antibacterial activities. The minimum biofilm inhibitory concentration (MBIC) of A7G against S. aureus and E. coli was 0.20 mg/mL and 0.10 mg/mL, respectively. The inhibition rates of 1/2 MIC of A7G on biofilms of S. aureus and E. coli were 88.9%, and 83.2% respectively. Moreover, atomic force microscope (AFM) images showed the three-dimensional biofilm morphology of S. aureus and E. coli, and the results indicated that A7G was highly effective in biofilm inhibition.Discussion: It was found that the inhibition of A7G on biofilm was achieved through inhibiting on exopolysaccharides (EPS), quorum sensing (QS), and cell surface hydrophobicity (CSH). A7G exerted strong anti-biofilm activities by inhibiting EPS production, QS, and CSH. Hence, A7G, as a natural substance, could be a promising novel antibacterial and anti-biofilm agent for control of biofilm in food industry.Keywords: apigenin-7-O-glucoside, anti-biofilm, exopolysaccharide, quorum sensing, cell surface hydrophobicity, atomic force microscope