Moderate Antioxidant Activity of Exopolysaccharides from Dangke Derived Enterococcus faecium

Abstract

Oxidative reactions contribute to food deterioration and are implicated in oxidative stress related disorders, motivating interest in natural antioxidants.This study evaluated the antioxidant activity of exopolysaccharides (EPS) produced by Enterococcus faecium strains isolated from Dangke, a traditional Indonesian dairy product.EPS were produced in a whey-based medium and recovered by heat treatment, enzymatic clarification, centrifugation, ethanol precipitation, dialysis, and freeze drying.Antioxidant capacity was quantified using a microplate-based 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.In the tested range (1-10 mg/mL), all EPS samples showed concentration-dependent scavenging but low potency at 10 mg/mL, inhibition reached 38.6-40.6%,whereas at 1 mg/mL it was 0.8-2.4%.Because 50% inhibition was not achieved within the tested range, EPS IC₅₀ values are reported conservatively as IC₅₀ > 10 mg/mL.Corresponding Trolox equivalent antioxidant capacity (TEAC) values are therefore reported as an upper bound (TEAC < 3.0 × 10⁻³ mg Trolox/mg EPS), indicating substantially lower activity than Trolox and ascorbic acid under the same assay conditions.Structural characterization and technological functionality tests were not performed.Therefore, mechanistic explanations and application claims remain beyond the scope of this work.Overall, this study provides a quantitative benchmark for EPS from a previously uncharacterized traditional dairy niche and supports prioritizing structural characterization and matrix-relevant assays in future screening.

Access to Document

Other files and links

• Link to publication in Scopus
• Open Access Version Available

Fingerprint