Antioxidant activities and chemical composition of rhizome essential oil from Zingiber plicatum Škorničk. & Q.B.Nguyen from Vietnam

Abstract

The Zingiber genus has been widely applied in food and pharmaceuticals due to its varied chemical composition and significant benefits. Zingiber plicatum Škorničk. & Q.B. Nguyễn was described in Vietnam in 2015, yet there has been no report on its phytochemicals and bioactivity. In this study, we first analyzed the chemical composition of essential oil and its antioxidant activities. Isolation of the rhizome essential oil was performed through hydrodistillation using a Clevenger apparatus for 3.5 h, then volatile compositions were determined using gas chromatography-mass spectroscopy (GC-MS). Additionally, the antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing power assays. The GC-MS analysis showed a total of 54 volatile components, mainly belonging to monoterpene hydrocarbons (57.69%) and sesquiterpene hydrocarbons (28.98%). The main compounds were β-pinene (26.85%), α-pinene (11.73%), limonene (10.03%), and germacrene D (5.26%). The essential oil also showed antioxidant activities, with an IC₅₀ of 84.53 mg/mL for DPPH scavenging activity and an EC₅₀ of 17.3 mg/mL for ferric reducing power. These findings first provided data on the chemical components and antioxidant properties of Z. plicatum essential oil.

Keywords:

• Zingiber plicatum
• Essential oil
• GC-MS
• Chemical composition
• Antioxidant activity