Antibacterial characteristics and mechanisms of some herbal extracts and ϵ-polylysine against two spoilage bacterial  

作　　者：Leila Bandian Mohhammad Moghaddam Massoumeh Bahreini Effat Vatankhah 

机构地区：[1]Department of Horticultural Science and Landscape Architecture,Faculty of Agriculture,Ferdowsi University of Mashhad,P.O.Box 91775-1163,Mashhad,Iran [2]Department of Biology,Faculty of Sciences,Ferdowsi University of Mashhad,Iran [3]Department of Chemistry,Faculty of Sciences,Ferdowsi University of Mashhad,Iran

出　　处：《Food Bioscience》2022年第6期537-545,共9页食品生物科学（英文）

摘　　要：This study aimed to evaluate the antibacterial effects of ε-polylysine (ε-PL) and plant extracts of Thymus vulgaris, Zataria multiflora, and Salvia verticillata against the spoilage bacterium Pseudomonas aeruginosa and Pectobacterium carotovorum . Chemical compounds contained in the plants extracts were detected using HPLC and H NMR assays. To determine the antimicrobial effects, the minimum inhibitory concentration (MIC) was calculated. Scanning electron microscopy (SEM) was used to evaluate the mode of action of plant extracts and ε-polylysine on bacteria. Bacterial membrane electrical conductivity was also measured to investigate the effect of treatments on electrolyte leakage. Based on HPLC results, rosmarinic acid, caffeic acid, gallic acid, and chlorogenic acid were identified as major chemical ingredients of the extracts. Based on HPLC results, chlorogenic acid in the T. vulgaris, Z. multiflora, and S. verticillata extracts with the values of 3.209, 3.163, and 1.455 mg/L, respectively, was the dominant compound. Gallic acid, carvacrol, and p -cymene were detected in the H NMR assay as predominant secondary metabolites. The results of SEM revealed that plant extracts and ε-polylysine caused deformity of bacterial membranes. Minimum inhibitory concentration values for T. vulgaris, ε-polylysine, Z. multiflora, and S. verticillata were determined to be 0.78, 1.56, 6.25, and 25 mg/L;respectively. The electrical conductivity of bacterial cell membranes followed a dose-dependent trend. The highest electrical conductivity was observed in T. vulgaris treatment, followed by ε-polylysine and Z. multiflora .

关 键 词：Ε-POLYLYSINE H NMR HPLC analysis Plant extracts Spoilage bacterium 

分 类 号：TS201.3[轻工技术与工程—食品科学]