CHEMICAL CHARACTERIZATION AND FREE RADICAL SCAVENGING ACTIVITY OF DENDROBIUM THONGCHAI EXTRACTS: A PROMISING SOURCE FOR NEUROPROTECTIVE AND ANTIMICROBIAL AGENTS

Objectives: This study assessed the potential of Dendrobium thongchai (gold) root extracts as sources of neuroprotective and antimicrobial compounds by characterizing their phytochemical constituents and antioxidant activity. Methods: Methanol and ethanol were used to macerate root powders, and the extraction yield was quantified using gravimetric analysis. Gas chromatography-mass spectrometry analyzed the methanolic (MeOH) extract, identifying compounds based on National Institute of Standards and Technology (NIST) library matches. Ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl assays measured antioxidant activity at five concentrations (0.8–4.0 mg/mL). Each assay was performed in triplicate, with statistical analysis using one-way analysis of variance and Tukey’s post hoc test to determine significant differences (p