Antibacterial activity of essential oils from twenty Curcuma aeruginosa genotypes

Abstract

Curcuma aeruginosa is a rhizome-like medicinal plant with many pharmacological properties. This research aimed to evaluate the antibacterial activity in essential oils from C. aeruginosa genotypes. Using hydrodistillation process, essential oils were acquired from twenty genotypes of C. aeruginosa rhizomes. Antibacterial activity of the samples has been evaluated using agar disk diffusion against Escherichia coli, Staphylococcus aureus, and Streptococcus mutants. Using the broth dilution process, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured for the selected bacteria. Twenty C. aeruginosa genotypes (excluding the G4, G8, G14 and G20 genotypes) demonstrated antibacterial activity against S aureus with varying levels of inhibition. The genotype G15 showed inhibition against E. coli, while the genotype G1, G2, G4, G12 and G16 presented inhibition against S mutants. These findings revealed that, compared with E. coli and S mutants, the essential oils of C. aeruginosa exhibited good antibacterial activity in S aureus. The MIC and MBC of twenty essential oils of C. aeruginosa genotypes against S aureus ranged from 7.81 to 2000 |ag/ml and 250 to 2000 |ag/ml, respectively. These findings suggest that the essential oils of C. aeruginosa may be used as a natural antibiotic to treat many infectious diseases caused by gram-positive bacteria.