Comparative Analysis of Virulence Factors and Antibiotic Resistance in Enterococci Isolated from Fruits and Vegetables

Abstract

Enterococci are a variety of Gram-positive cocci that live in a variety of environments, such as food, plants, and gastrointestinal tracts (GI). Hospital-acquired multidrug resistance is on an upward trajectory. The increasing number of reports of Enterococcus strains linked to bloodstream infections, endocarditis, and urinary tract infections highlights the critical need for surveillance and research on antimicrobial resistance (AMR). While multidrug resistance refers to resistance to various antibiotic classes, which complicates therapy and raises the chance of clinical failure, antibiotic resistance is the ability of bacteria to resist the toxic effects of drugs that previously killed them. With a focus on virulence factors and AMR profiles, this study examines the occurrence and characteristics of Enterococcus strains in various environments. As 48 samples of raw vegetables and fruits were examined, 46 of them tested positive for Enterococci (93%), indicating a high tolerance to salt and variation in gelatinase activity (32.6%). Each isolate had the ability to hydrolyze esculin, and the tube adherence test method verified that biofilm development was seen in 56.5% samples. The surface morphology of biofilm-positive cells which are adhered to solid surfaces and form multicellular aggregates packed into extracellular matrix material and biofilm-negative cells which lack matrix material, were shown by scanning electron microscopy (SEM). Antibiotic resistance patterns differed; vegetable-associated Enterococci showed significant resistance to Ampicillin (20.7%) and Erythromycin (17.2%), while fruit-associated Enterococci showed concerning resistance to Linezolid and Vancomycin (35.3%). In order to assure food safety and public health, this study emphasizes the various characteristics of Enterococcus isolates and stresses the significance of surveillance and treatment with antibiotics for environmental Enterococcus strains.