Antioxidant Activity, Lipid Peroxidation Suppression and Preliminary Toxicity Assessment of Persicaria Minor (Kesum) Aqueous Extract

Abstract

Persicaria minor is a widely consumed Southeast Asian herb with emerging pharmacological relevance; however, comprehensive evaluation integrating antioxidant efficacy and safety profiling remains limited. This study systematically investigated the in vitro antioxidant capacity, in vitro lipid peroxidation modulation, and preliminary toxicity profile of the aqueous leaf extract of P. minor. Antioxidant activity was assessed using DPPH radical scavenging and ferric reducing antioxidant power (FRAP) assays, while total phenolic content (TPC) was quantified via the Folin–Ciocalteu method. Oxidative stress attenuation was evaluated by measuring malondialdehyde (MDA) levels, and preliminary safety was determined using the Brine Shrimp Lethality Test (BSLT). The extract demonstrated total phenolic content reaching approximately 500 mg GAE/g at 1 mg/mL. DPPH radical scavenging activity ranged from approximately 73–94% inhibition across concentrations (0.046875–6 mg/mL), approaching the activity of ascorbic acid (~98%) at higher doses. FRAP analysis revealed consistent ferric reducing capacity, with values around 159.5–159.7 µmol Fe²⁺ equivalents across tested concentrations. In the lipid peroxidation model, MDA levels were reduced from approximately 4.6–4.8 nmol/mg protein in the negative control to about 1.8–1.9 nmol/mg protein in the treated group, representing roughly 55–60% inhibition. Brine shrimp survival rates remained above 80% across concentrations (0.097–100 mg/mL), with no LC₅₀ detected within the tested range, indicating low acute toxicity. Collectively, these findings demonstrate that P. minor aqueous extract possesses potent antioxidant activity, effectively mitigates lipid peroxidation, and exhibits minimal preliminary toxicity, highlighting its potential as a safe natural antioxidant candidate for further pharmacological and toxicological investigations.