Anticancer, antioxidant, and antibacterial effects of nanoemulsion of Origanum majorana essential oil

This study aimed to develop a natural nanoemulsion with antibacterial and anticancer properties.

The chemical composition of the Origanum majorana essential oil was investigated using GC–MS analysis. Besides, the successful loading of the essential oil in the nanoemulsion was confirmed using ATR-FTIR analysis. Moreover, nanoemulsion’s anticancer, antioxidant, and antibacterial activities were investigated.

Terpinen-4-o1 (46.90%) was identified as the major compound in the essential oil. The nanoemulsion with a 149 ± 5 nm droplet size and zeta potential of -11 ± 1 mV was prepared. The cytotoxic effect of the nanoemulsion against A-375 human melanoma cells (IC50 = 139 µg/mL) showed significantly more potency than A-549 human lung cancer cells (IC50 = 318 µg/mL). Interestingly, growth of Staphylococcus aureus (Gram-positive) and E. coli (Gram-negative) bacteria after treatment with 4800 µg/mL of nanoemulsion were obtained at 12 ± 2 and 6 ± 1%, respectively. However, the IC50 value of nanoemulsion against E. coli (580 µg/mL) was not significantly different (P > 0.05) from S. aureus (611 µg/mL).

A straightforward preparation method, high stability, and multi-biological effects are the main advantages of the prepared nanoemulsion. Therefore it could be considered for further investigation in vivo studies or complementary medicine.