Syzygium nervosum extraction and potent bioactivities

Syzygium nervosum leaves have been used in life the Vietnamese regularly as a beverage. S. nervosum leaves were extracted by ultrasonic - assisted extraction method, with the ratio of ingredients: ethanol 99 % = 1 : 30 (w/v), in 30 minutes, at 50 °C, then sonicated for 5 minutes at an ultrasonic frequency of 20 kHz. The result of the content of total polyphenol and total flavonoid was: 67.55 ± 2.28 mg/g and 93.78 ± 6.04 mg/g, respectively. The extraction showed the following results of bioactivities: α - glucosidase enzyme inhibition, IC 50 = 0.60 ± 0.11 µg/mL, free radical resistance, IC 50 = 14.50 ± 0.71 µg/mL, cholesterol resistance, IC 20 = 166.38 µg/mL and anti - inflammatory, IC 50 = 351.95 ± 1.98 μg/mL. Our analysis showed potential bioactivities on diabetes, support digestion and inflammatory diseases of Syzygium nervosum leaves in Vietnam.