Oven-dried and powdered roots of A. chilensis (40 g) were extracted with light petroleum ether (35-65º) in a Soxhlet apparatus, and the defatted plant material was then extracted with MeOH. The methanolic extract was evaporated in vacuo. The syrupy residue was agitated with 100 mL of 3% NaHCO3 for 6 h, allowed to stand for 24 h at 10 ºC, and filtered. The clear filtrate was washed with CHCl3 (5 x 50 mL). Upon evaporation, the washings with CHCl3 yielded a brown gum that contained no acids and was not further investigated. The aqueous phase was adjusted to pH 2 with HCl and extracted with CHCl3 (6 x 50 mL). Evaporation of the combined extracts in vacuo yielded a fraction of crude non-phenolic AAs (43.4 mg) 22. The acid solution was then extracted with AcOEt (6 x 50 mL). Evaporation of the combined extracts in vacuo yielded a second fraction of crude phenolic AAs (103 mg). The fraction of crude phenolic AAs was re-suspended in 10 mL of 3% NaHCO3 and filtered. The clear filtrate was adjusted to pH 2 with HCl and extracted with AcOEt (6 x 10 mL). Evaporation of the combined extracts in vacuo yielded a purified fraction of phenolic AAs (45.5 mg)

Thank s  for your answer Dr.Alejandro Urzua