Potentiation of Antimicrobial Activity of Aminoglycosides by Carnosol from Salvia officinalis

Abstract

We found that a crude extract from Salvia officinalis (sage) reduced the minimum inhibitory concentrations (MICs) of aminoglycosides in vancomycin-resistant enterococci (VRE). We isolated the effective compound from the extract and identified it as carnosol, one of diterpenoids. Carnosol showed a weak antimicrobial activity, and greatly reduced the MICs of various aminoglycosides (potentiated the antimicrobial activity of aminoglycosides) and some other types of antimicrobial agents in VRE. Carnosic acid, a related compound, showed the similar activity. The effect of carnosol and carnosic acid with gentamicin was synergistic.

Evaluation of the Antimicrobial Activity of Tribulus terrestris, Allium sativum, Salvia officinalis, and Allium hirtifolium Boiss Against Enterococcus faecalis

“…16,[35][36][37][38] Horiuchi et al demonstrated a synergistic effect of S. officinalis extract with aminoglycosides in elimination of certain infections. 39,40 On the contrary, some studies did indicate no antibacterial activity against E. coli and P. aeruginosa. 41 In general, according to the available literature, the effect of S. officinalis extract against E. faecalis is controversial.…”

Antibacterial effect of chlorhexidine-cetrimide combination, <i>Salvia officinalis</i> plant extract and octenidine in comparison with conventional endodontic irrigants

“…officinalis as a source of natural antioxidants used in health care products has been shown to be nontoxic to rat hepatocytes with diluted concentrations of the extract 43) . In addition, Horiuchi et al 33) isolated the effective compounds from S. officinalis extract and identified them as carnosol and carnosic acid. They also claimed that carnosol and carnosic acid increase the gram-positive bacteria cell membrane permeability, thereby improving the diffusion of antimicrobial agents into the cells.…”

“…The antimicrobial efficacy of S. officinalis against E. faecalis has been investigated using the agar diffusion method 33,34) . However, the studies had observed the bacterial activity of the extracts against planktonic forms only.…”

“…S. officinalis is used both in culinary and medicinal preparations 27) . Therapeutic effects including antioxidant, antispasmodic, antimicrobial, anti-inflammatory, carminative and mucolytic agent; as well as a hormonal regulator and to control mild to moderate states of Alzheimer's disease, reducing patients agitation have already been reported [27][28][29][30][31][32][33][34] . Although data from the previous studies is not strictly relevant to endodontics, the safe use of S. officinalis extract for the treatment of several human ailments generally refers to its use will most likely be safe for endodontic purposes as well.…”

Gene Cloning and Characterization of EfmA, a Multidrug Efflux Pump, from Enterococcus faecium

“…Bacteria and Growth E. faecium FN-1, 18) used as a donor of chromosomal DNA, was kindly provided by Dr. Y. Ike (Gunma University). This strain is a clinical isolate.…”