Abstract

Buchanania siamensis is a local plant in eastern and north-eastern Thailand belonging to the Anacardiaceae family. The plant provides shading and is a good source of food and medicine since its fruits possess antioxidant and anti-cancer effects. The green, environmental-friendly, extraction of B. siamensis, under ultrasound- and microwave-assisted extraction, using solvents consisting of a variation of tween 80, propylene glycol (PG), and ethanol concentrations were investigated. Extraction by aqueous PG under ultrasound-assisted extraction (UAE) conditions yielded the highest total phenolic (TPC) and total flavonoid contents (TFC). The optimum condition, which was using a 40 mL/g ratio, 50% PG at 60°C for 20 min, yielded the extract with TPC at 49.12 ± 0.51 mgGAE/g DW and TFC at 14.18 ± 0.48 mgQE/g DW. The extract exhibited antioxidant activity at IC<inf>50</inf> 2.49 ± 0.03 mg/mL. Water-based formulations (solution and hydrogel) of this extract were successfully fabricated. The formulations demonstrated stable properties, TPC, myriscitrin, quercetrin content, and antioxidant properties after the heating and cooling test (6 cycles). Consequently, the B. siamensis extract, rich in antioxidative agents, was proper for incorporation into water-based cosmeceutical products.