Phytochemical profiling, antioxidant, α-glucosidase inhibitory, and anti-inflammatory activities of Grangea maderaspatana essential oil: Experimental and molecular docking studies
Abstract
Background: Grangea maderaspatana is traditionally used for its heat-clearing, detoxifying, anti-inflammatory, and antipyretic properties. Questions: What are the major phytochemical compositions of essential oils from G. maderaspatana? Have they antioxidant, anti-α-glucosidase, and anti-inflammatory properties? Studied species: Grangea maderaspatana (L.) Desf. (Asteraceae) Study site and dates: Quang Nam, Vietnam, 2025-2026 Methods: Volatile oil constituents were identified using gas chromatography-mass spectrometry analysis. Essential oils were evaluated for antioxidant, anti-α-glucosidase, and anti-inflammatory activities using DPPH scavenging, α-glucosidase inhibition, and LPS-induced RAW264.7 cell assays, respectively. Molecular docking was performed to further support in vitro findings. Results: The main compositions of essential oils were α-humulene, β-myrcene, germacrene D, limonene, β-elemene, β-caryophyllene, β-pinene, ar-curcumene, and caryophyllene oxide. Essential oils exhibited antioxidant activity (IC50= 243.69 µg/mL) and α-glucosidase inhibitory activity (IC50 = 180.33 µg/mL). Essential oils inhibited NO production in RAW264.7 cells (IC50 = 50.25 µg/mL). These findings provide preliminary evidence of the biological activities of essential oils. Docking studies of the oil constituents, including δ-cadinene (-6.9 kcal/mol) and larixol (-6.8 kcal/mol), indicated favorable binding to α-glucosidase. Furthermore, β-curcumene, δ-cadinene, and α-cubebene showed the most favorable docking scores among the identified constituents against iNOS and IL-1β, with binding energies ranging from -7.0 to -7.1 kcal/mol and -6.8 kcal/mol, respectively. Conclusions: These findings suggest that G. maderaspatana essential oils has promising medicinal applications as a source of antioxidant, anti-inflammatory, and α-glucosidase inhibitory agents.