Antioxidant Activity and Molecular Docking Study of Volatile Constituents from Different Aromatic Lamiaceous Plants Cultivated in Madinah Monawara, Saudi Arabia

• Main Authors: Amr Farouk, Mohamed Mohsen, Hatem Ali, Hamdy Shaaban, Najla Albaridi
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Molecules
• Subjects: essential oil; GC-MS; <i>Mentha longifolia</i> L.; <i>Mentha spicata</i> L.; <i>Origanum majorana</i> L.; antioxidant potential
• Online Access: https://www.mdpi.com/1420-3049/26/14/4145

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from <i>Mentha longifolia</i> L., <i>Mentha spicata</i> L., and <i>Origanum majorana</i> L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in <i>M. longifolia, M. spicata,</i> and <i>O. majorana</i> representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in <i>M. longifolia</i> oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and β-caryophyllene (3.02%) were dominant in <i>M. spicata</i> oil; terpin-4-ol (42.47%), <i>trans</i>-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and <i>cis</i>-sabinene hydrate (3.14%) were dominant in <i>O. majorana</i> oil. The antioxidant activity, assessed using DPPH free radical–scavenging and ABTS assays, was found to be the highest in <i>O. majorana</i> volatile oil, followed by <i>M. spicata</i> and <i>M. longifolia</i>, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for <i>cis</i>-verbenyl acetate, followed by β-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.