In Vitro Free Radical Scavenging and Cell-Based Antioxidant Activities of Kheaw-Hom Remedy Extracts and Its Plant Ingredients
Kulisara Ouncharoen BMTA*, Arunporn Itharat PhD**,***, Pannawat Chaiyawatthanananthn PhD**,***
Affiliation : * Student of Master of Science in Applied Thai Traditional Medicine, Faculty of Medicine, Thammasat University, Pathumthani, Thailand ** Department of Applied Thai Traditional Medicine, Faculty of Medicine, Thammasat University, Klongluang, Pathumthani, Thailand *** Center of Excellence on Applied Thai Traditional Medicine Research (CEATMR), Faculty of Medicine, Thammasat University, Klongluang, Pathumthani, Thailand
Background : The oxidative stress (OS) and antioxidants play a key role in the pathogenesis of inflammatory diseases such
as fever which is promoted by the production of reactive oxygen species and impaired antioxidant defense mechanisms. The
Kheaw-Hom remedy is popularly used as anti-pyretic drug in Thai traditional medicine.
Objective : To investigate antioxidant activity of the ethanolic and aqueous extracts of Kheaw-Hom remedy and its plant
ingredients by three assays such as DPPH, ABTS radical scavenging assays and NBT dye reduction assay.
Material and Method: The extract procedures were maceration method with 95% ethanol, dried by an evaporator, or the
decoction by boiling in water, filtrated, dried by lyophilizer. In the preliminary studies, all extracts were evaluated for
antioxidant activity through two chemical assays: DPPH radical-scavenging and ABTS radical-scavenging assay, as well as
through cell-based assay: scavenging capacity of intracellular ROS in HL-60 cells using the NBT reduction.
Results : The ethanolic extract of Khaew-Hom remedy showed higher antioxidant activity using DPPH and ABTS assays but
it had no antioxidant activity using cell-based assay (EC50 = 16.96, 30.91 and IC50 >100 μg/mL, respectively). The ethanolic
extract of Cyathea gigantea and Tacca chantrieri showed the highest antioxidant activity using DPPH assay with EC50 = 7.55
and 8.00 μg/mL, respectively. The ethanolic extract of Dracaena loureiri and Globba malaccensis exhibited the best antioxidant
activity using ABTS radical scavenging with EC50 = 7.88 and 8.06 μg/mL, respectively. For the NBT dye reduction assay, only
the ethanolic and aqueous extracts of Tacca chantrieri were effective having IC50 = 63.38 and 70.65 μg/mL, respectively.
Conclusion : The ethanolic of Khaew-Hom showed antioxidant activity only with chemical based assay but both ethanolic and
aqueous extracts of Tacca chantrieri (rhizome) showed high antioxidant activities on chemical-based and cell line-based
assay. Thus, this plant should be developed to be health products in the future.
Keywords : Antioxidant activities, Kheaw-Hom, DPPH, ABTS, NBT assay, HL-60
