The chemicals and reagent used in this study were ethanol, quercetin, aluminum chloride 10%, sodium acetate 1 M, water, Folin-Ciocalteu reagent, gallic acid, natrium hydroxide 1%, chloroform-saturated water, hydrochloric acid, and helium gas. Meanwhile, the teak leaves were obtained from Jebres, Central Java, Indonesia. The samples were obtained from the forest in the form of fresh and dried flowers. The samples were obtained between May and