Figure 1. Disk diffusion tests and inhibition zone diameters for Grapefruit seed extract (GSE) Figure 1. Disk diffusion tests and inhibition zone diameters for Grapefruit seed extract (GSE) and and linezolid (LZD) against methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant linezolid (LZD) against methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. S. aureus (MRSA), and VRSA. ( A ) S. aureus ATCC 6538 (MSSA), ( B ) S. aureus ATCC 33591 (MRSA), aureus (MRSA), and VRSA. ( A ) S. aureus ATCC 6538 (MSSA), ( B ) S. aureus ATCC 33591 (MRSA), ( C ) ( C ) S. aureus CCARM 3795 (MRSA), and ( D ) vancomycin-resistant S. aureus (VRSA48). The concen- S. aureus CCARM 3795 (MRSA), and ( D ) vancomycin-resistant S. aureus (VRSA48). The concentra- tration of LZD was 30 µ g/disk, following the CLSI guidelines. The diameters of the inhibition zones for GSE and LZD are illustrated by the bar graphs as the means ± SD ( n = 3). All tested bacteria were susceptible to LZD, according to the CLSI guidelines ( ≥ 21 mm for Staphylococcus spp.), and GSE also showed antibacterial effects against all tested bacteria. p values were calculated using two-tailed, unpaired t -tests in this figure. **** p <