Hydrodistillation and simultaneous hydrodistillation-steam distillation of Rosmarinus officinalis and Origanum compactum: Antioxidant, anti-inflammatory, and antibacterial effect of the essential oils

The essential oils (EOs) have been widely investigated for their antibacterial, antioxidant and anti-inflammatory properties, which are influenced by several factors such as the extraction processes. The aim of this study was to investigate the antibacterial activities (two strains of Escherichia coli, Staphylococcus aureus, and S. saprophyticus) of Rosmarinus officinalis L. (M1) and Origanum compactum Benth. (M11) EOs obtained by hydrodistillation, and their combinations obtained by a combined hydrodistillation and steam distillation. The antioxidant and inhibitory activities of R. officinalis, O. compactuum, and the binary combination 50:50 on lipoxygenase, acetylcholinesterase, and tyrosinase were also evaluated. The chemical composition was determined using the gas chromatography coupled to mass spectrometry (GC-MS) analysis and the quantification by the external standard method. The simultaneous extraction of EOs from two plants permitted obtaining EOs with better antimicrobial activity than those obtained individually by hydrodistillation. The capacity for scavenging the hydrogen peroxide, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals, and for inhibiting the lipoxygenase activity were also better for the essential oil mixture obtained by the simultaneous extraction of EOs. In conclusion, the combined hydrodistillation-steam distillation improved the EOs yields and their biological activities with the advantage of reducing the extraction time, and consequently energy consumption.

Automated summary

This study aimed to investigate the antibacterial activities of two essential oils against multiple bacteria, and the results showed that essential oils obtained by simultaneous extraction had better antimicrobial and antioxidant activities.