Abstract:
Leum Pua rice is a traditional black glutinous rice, contains higher nutritional value compared to common white rice. This study aimed to compare the bioactive compound and cosmetic bioactivities of Leum Pua rice extracts obtained through maceration and ultrasonic-assisted extraction with 70% ethanol and propylene glycol as solvents. The extracted samples were analyzed for anthocyanin content, total phenolic content, total flavonoid content, antioxidant activity, antiglycation, and tyrosinase inhibition. The results showed that ultrasonic-assisted extraction using 70% ethanol for 30 minutes yielded the highest anthocyanin content (12.89 ± 0.26 mg CEG/100g), as well as higher total phenolic content (5.24 ± 0.12 mg GAE/g) and total flavonoid content (19.60 ± 0.24 mg QE/g) compared to maceration. In addition, ultrasound-assisted extraction exhibited significantly stronger biological activities relevant to cosmetics, as indicated by lower IC50 values for antioxidant activity (6.63 ± 0.25 µg/mL), antiglycation activity (26.07 ± 0.84 µg/mL), and tyrosinase inhibition (44.43 ± 0.97 µg/mL) (p ≤ 0.05). In conclusion, ultrasonic-assisted extraction is more efficient for extracting active compounds from Leum Pua rice in a shorter time and is suitable for experiments that demand speed and high efficiency.