<b>Background and Objective:</b> <i>Etlingera alba </i>(Blume) A.D. Poulsen is one of the plants of the genus <i>Etlingera</i> which is commonly found in Southeast Sulawesi. The research is still lacking, thus, we assumed other species related to <i>E. alba,</i> specifically from the genus<i> Etlingera</i> that provides antioxidant and radical scavenging activity, namely <i>Etlingera elatior</i> (Jack) R.M. Smith. Thus, this study aimed to assess the antioxidant and toxicity activity as well as its secondary metabolites. <b>Materials and Methods:</b> <i>Etlingera alba</i> rhizome was extracted with 96% ethanol. The radical scavenging activity was assayed with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and antioxidant activity was assayed with 2,2'-azino-bis-[3-ethylbenzothiazoline sulphonate (ABTS) assay for radical cation decolourization<i> in vitro</i>. Both Ascorbic Acid (AA) and Trolox were used as positive control. The secondary metabolites were identified by Thin Layer Chromatography (TLC) and LSMS/MS analyzed the difference between compounds. According to results performed with TLC and LCMS/MS. <b>Results:</b> The extract exhibited antioxidant properties using both DPPH and ABTS method. The LC<sub>50</sub> of the extract was 608.42±18.31 mg L<sup></sup><sup>1</sup>.<i> Etlingera alba </i>rhizome extract contains alkaloids, flavonoids, terpenoids and steroids. The compounds detected in the extract were E-p-Coumaric acid aschantin, 2-Methoxyanofinic acid, Chavicol-β-D-glucoside, Myristicanol B, ent-16α,17-Hydroxy-19-kaurenoic acid, 5-Hydroxy-7,8,2'-trimethoxyflavone, Methyl ursolate and Spinasterol. <b>Conclusion:</b> <i>Etlingera alba</i> rhizome contains several compounds that might be responsible for antioxidant activity and the extract itself classified as medium toxic.
Keywords: 1; 1-diphenyl-2-picrylhydrazyl (DPPH) assay; 2; 2�-azino-bis-[3-ethylbenzothiazoline sulphonate (ABTS) assay; Etlingera alba; antioxidant activity; decolourization; flavonoids; thin layer chromatography.