Microscopic Characteristics, Chemical Composition and Antioxidant Activity of Stem and Leaf Extracts of Scurrula atropurpurea (Blume) Danser. Hemiparasite on Erythrophleum succirubrum Gagnep.

Scurrula atropurpurea (Blume) Dans. is a hemiparasitic plant that parasitizes a variety of host plants. It is used traditionally for treating various ailments. The chemical composition and antioxidant properties of this plant, particularly when attached to Erythrophleum succirubrum are not well documented. This study aimed to provide a pharmacognostic description, and evaluate the chemical composition and antioxidant activity of the stem and leaf extracts of S. atropurpurea and E. succirubrum. The extracts were obtained by Soxhlet extraction using dichloromethane, ethyl acetate, and ethanol, successively. The pharmacognostic features of S. atropurpurea was examined microscopically. The total phenolic and flavonoid contents were evaluated using standard methods. The antioxidant activity was assessed using DPPH and ABTS radical scavenging assays. The compounds in the extracts were identified by GC-MS analysis. Results showed that the ethanol extract of S. atropurpurea stem had the highest total phenolic content (387.365±4.643 mg GAE/g extract), while the dichloromethane extract of E. succirubrum leaf had the highest total flavonoid content (170.311±2.20 mg QE/g extract). The ethanol extract of E. succirubrum stem had the highest antioxidant activity (IC50 = 0.290±0.029 mg/mL) in the DPPH assay, while the ethanol stem extract of S. atropurpurea had the highest antioxidant activity (IC50 = 0.509±0.041 mg/mL) in the ABTS assay. GC-MS analysis identified 13 compounds in the extracts of S. atropurpurea with the major constituents being 9-octadecanamide (Z)-, tetradecanamide, octadecanamide, and hexadecanamide. S. atropurpurea extracts exhibited significant antioxidant activity, underscoring the plant's potential therapeutic value and supporting its traditional use in folk medicine.