Evaluation of antioxidant activity and antimicrobial activity of vietnamese rosemary (Rosmarinus officinalis L.) essential oils extracted by some extraction methods Available to Purchase

Rosemary (Rosmarinus officinalis L.) is a perennial herb in the family Lamiaceae, widely grown worldwide, and has many interesting bioactive components that improve human health. In this study, the antimicrobial and antioxidant activity of rosemary essential oil obtained by three extraction methods: Hydrodistillation, Steam Distillation, and Microwave-Assisted Hydrodistillation were assayed and compared. The chemical compositions of the essential oils were also determined. The compounds which were identified with high content included α-Pinene (18.317%, 23.455%, 25.667%), Eucalyptol (20.269%, 15.24%, 16.924%), Verbenone (11.56%, 10.111%, 11.881%) and Bornyl acetate (8.116%, 10.111%, 7.516%). The antioxidant activity was determined in vitro using the free radical capture method DPPH and ABTS. The antimicrobial activity of essential oils in the study was determined by agar disk diffusion assay. Among the three methods, rosemary essential oil obtained from (MAHD) showed better DPPH and ABTS free radical scavenging with IC50 values of 5.47±1.2 mg/mL and 0.66±0.02 mg/mL compared with rosemary essential oil obtained from (HD) was 14.13±11.3 mg/mL and 0.67±0.09 and (SD) was 27.77±1.0 mg/mL and 4.16±0.15 mg/mL. Notably, the results of the antimicrobial activity test of the three essential oils obtained in the study showed strong inhibitory development bacterial effects against S. aureus, E. coli, S. Typhimurium, and weaker against P. aeruginosa. Rosemary essential oil was obtained using the three methods with antioxidant and antimicrobial activity. Consequently, rosemary essential oil could be pharmaceutical native to plants with the potential to replace antibiotics and treat free radical diseases in the future.