Evaluation of anticancer, antimicrobial, and antioxidant activities of rosemary (Rosmarinus Officinalis) essential oil and its Nanoemulgel

Abstract

Throughout history, natural herbal medicines have been used to treat a wide range of serious diseases. This study aimed to develop rosemary oil into a nanoemulgel and evaluate its antimicrobial and anticancer activities. Rosmarinus officinalis (R. officinalis) oil was developed into a nanoemulgel by using a self-nanoemulsifying technique with Tween 80 and Span 80. The hydrogel (Carbopol 940) was then incorporated into the nanoemulsion and mixed well. After this, the antioxidant activity of the R. officinalis oil was measured and its nanoemulgel droplet size, polydispersity index (PDI), rheology, antimicrobial effect, and cytotoxic activity were investigated. The optimum formulation (50% Tween, 15% Span 80, and 35% R. officinalis oil) was used to create the best nanoemulsion, that had droplet size of 159.23 ±1.22 nm and 0.206 ±0.08 PDI. R. officinalis showed strong antioxidant activity, with 22.38 ±0.7 μg/mL when compared to trolox (2.7 ±0.5 μg/mL). Interesting results were obtained with the nanoemulgel against different types of bacteria, such as Pseudomonas aeruginosa, Klebsiella pneumoniae, and Methicillin-resistant staphylococcus aureus (MRSA), with a minimum inhibitory concentration (MIC) of 2.3, 3.75, and 6.5 µg/mL, respectively. In addition, the half-maximal inhibitory concentration (IC50) of the nanoemulgel when applying it to human hepatocellular carcinoma cells (Hep3B) and human cervical epithelioid carcinoma cells (HeLa) was 28.84, 28.18, and 24.54 µg/mL, respectively, which demonstrated that the nanoemulgel has anticancer effects. In conclusion, R. officinalis oil nanoemulgel would be a promising novel dosage form for pharmaceutical industries to be used for the treatment of different cancer cell lines and microbial infections.