Antibacterial, antioxidant, and wound healing properties of extract and phytochemicals of Dracontomelon dao (Blanco) Merr. & Rolfe bark

Abstract

Introduction Dracontomelon dao (Blanco) Merr. & Rolfe ( D. dao ), commonly known in Thailand as Phrachao Ha Phra Ong, is recognised for its therapeutic applications and is particularly used in traditional medicine for ulcers and infections. This study aims to determine the antioxidant activity, antibacterial activity, and wound-healing properties of D. dao bark ethanol extract. Methods D. dao bark was extracted using 60% ethanol and then was investigated for phytochemicals and in vitro antioxidant and antibacterial activities, along with the wound healing properties. Results The extract demonstrated high phenolic (474.58 mg GAE/g) and flavonoid contents (48.06 mg QE/g), along with strong antioxidant activity that might be attributed to long-chain fatty acids. Moreover, treatment with D. dao bark extract inhibited hydrogen peroxide-induced reactive oxygen species production in a dose-dependent manner in primary normal human dermal fibroblast and human embryonic kidney-293 cells. In addition, treatment of human embryonic kidney-293 cells with the extract (50 μg/mL) significantly upregulated the mRNA expression of catalase and glutathione peroxidase-1, supporting its role in cellular antioxidant defence. Antibacterial activity by the agar disc diffusion method revealed significant inhibitory effects on Staphylococcus aureus and Methicillin-resistant S. aureus with minimum inhibitory concentration and minimum bactericidal concentration values of 0.49 mg/mL and 0.98 mg/mL, respectively. The D. dao bark extract also promoted fibroblast migration, as determined by wound-healing assays in primary normal human dermal fibroblast cells, indicating potential applications in tissue regeneration without cytotoxic effects. Conclusions These findings position D. dao bark extract as a promising candidate for developing natural antioxidant, antibacterial, and wound-healing agents, warranting further research into its therapeutic applications.