Essential oils from Egyptian aromatic plants as antioxidant and novel anticancer agents in human cancer cell lines

Abstract

SUMMARY:Inhibitors of tumor growth using extracts from aromatic plants are rapidly emerging as important new drug candidates for cancer therapy. The cytotoxicity and in vitro anticancer evaluation of the essential oils from thyme, juniper and clove has been assessed against five different human cancer cell lines (liver HepG2, breast MCF-7, prostate PC3, colon HCT116 and lung A549). A GC/MS analysis revealed that α-pinene, thymol and eugenol are the major components of Egyptian juniper, thyme and clove oils with concentrations of 31.19%, 79.15% and 82.71%, respectively. Strong antioxidant profiles of all the oils are revealed in vitro by DPPH and β-carotene bleaching assays. The results showed that clove oil was similarly potent to the reference drug, doxorubicin in prostate, colon and lung cell lines. Thyme oil was more effective than the doxorubicin in breast and lung cell lines while juniper oil was more effective than the doxorubicin in all the tested cancer cell lines except prostate cancer. In conclusion, the essential oils from Egyptian aromatic plants can be used as good candidates for novel therapeutic strategies for cancer as they possess significant anticancer activity. KEYWORDS:Anticancer; Antioxidant; Clove Juniper; Thyme RESUMEN: Aceites esenciales de plantas aromáticas egipcias como novedosos agentes anticancerígenos y antioxidantes en líneas celulares de cáncer humano. Los inhibidores de crecimiento de tumores usando extractos de plantas aromáticas están emergiendo con rapidez como nuevos e importantes medicamentos para el tratamiento del cáncer. La citotoxicidad y la acción anticancerígena in vitro de aceites esenciales de tomillo, enebro y clavo han sido evaluadas en cinco líneas celulares de cáncer humano (hígado HepG2, mama MCF-7, próstata PC3, colon HCT116 y pulmón A549). Los análisis de GC/MS mostraron que α-pineno, timol y eugenol son los principales componentes de los aceites egipcios de enebro, tomillo y clavo, con concentraciones de 31,19%, 79,15% y 82,71%, respectivamente. Se demuestra, mediante ensayos in vitro de blanqueo de DPPH y β-caroteno, el enérgico perfil antioxidante de todos los aceites. Los resultados mostraron que el aceite de clavo fue similar de potente al fármaco de referencia, doxorrubicina en las líneas celulares de próstata, colon y pulmón. El aceite de tomillo fue más efectivo que la doxorrubicina en las líneas celulares de mama y de pulmón, mientras que el aceite de enebro fue más eficaz que la doxorrubicina en todas las líneas celulares de cáncer ensayados, excepto en la de cáncer de próstata. En conclusión, los aceites esenciales de plantas aromáticas egipcias se pueden utilizar como buenos candidatos para nuevas estrategias terapéuticas para el cáncer al poseer una significativa actividad anticancerígena

Secondary metabolites (essential oils) from sand-dune plants induce cytotoxic effects in cancer cells

“…A study by Lone and colleagues showed that EO extracted from the leaf of Senecio graciliflorus was able to induce a strong therapeutic effect against human lung cancer cell lines, with this activity attributed to the main components of the EO, α-pinene (a monoterpene also present in S. tortuosum in the present study) and ocimene (Lone et al, 2014). In another study, Ramadan and coworkers showed that Egyptian juniper oil, containing 26.19% of α-pinene, was associated with a more pronounced anticancer effect against HepG2, MCF7, and A549 cancer cell lines when compared with the commonly used chemotherapeutic drug, Doxorubicin (Ramadan et al, 2015). E. maritimum EO was shown to be composed predominantly by sesquiterpenes, including germacrene D. A recent study investigating the activity of EOs from Magnolia grandiflora flowers, containing in majority monoterpenes and sesquiterpenes, including germacrene D (sesquiterpene present in E. maritimum EO) and β-pinene (monoterpene present in A. campestris and S. tortuosum EOs) induced a cytotoxic effect against various cancer cell lines (Morshedloo et al, 2017).…”

Clove Essential Oil (Syzygium aromaticum L. Myrtaceae): Extraction, Chemical Composition, Food Applications, and Essential Bioactivity for Human Health

“…Diseases such as cancer, arteriosclerosis, Alzheimer's disease, and Parkinson's disease are related to the presence of ROS compounds [110]. CEO has shown scavenging activity on radicals and inhibition of lipid peroxidation [41,93]. The hydroxyl group available in eugenol on the aromatic ring is responsible for the antioxidant activity [99].…”

Clove Essential Oil (<em>Syzygium aromaticum L. Myrtaceae</em>): Extraction, Chemical Composition, Food Applications and Essential Bioactivities for Human Health

“…Diseases such as cancer, arteriosclerosis, Alzheimer's disease, and Parkinson's disease are related to the presence of ROS compounds [100]. The CEO had shown scavenging activity on radicals and inhibition of lipid peroxidation [32,83]. The hydroxyl group available in eugenol on the aromatic ring is responsible for the antioxidant activities [89].…”

“…Its anticancer activity is mainly attributed to its antioxidant and anti-inflammatory activity since the production of ROS specifically activates signaling pathways and contributes to the development of tumors by regulating cell proliferation, angiogenesis, and metastasis [100,106]. The CEO have been tested against different cancer types, such as colon [32,83], lung [83,85], breast [85], pancreas [32], leukemia [32,84], breast [32], cervix [32], and prostate [32,83].…”