Hasibuan, P.Y., Daulay , A.S., Ridwanto, R. and Pulungan , A.F. 2025. Determination of Tannin Content in Mangkokan Leaves (Polyscias scutellaria (Burm.f.) Fosberg) and Guava Leaves (Psidium guajava L.) Using UV-Vis Spectrophotometry. Journal of Pharmaceutical and Sciences. 8, 4 (Dec. 2025), 3048–3057. DOI:https://doi.org/10.36490/journal-jps.com.v8i4.972.