Application of Ultrasound-Assisted Extraction on the Stem Bark of Rhinachantus Nasutus (L.) Kurz, Total Phenolic, and Its Potential as Antioxidant and Inhibitor of Alpha-Glucosidase Enzyme Activity, Irawan, Candra, Elya Berna, Hanafi Muhammad, and Saputri Fadlina Chany , Pharmacognosy Journal, September 2021, Volume 13, Issue 5, p.1297-1303, (2021)