Dian Fatimatus Salwa; Tatiana Siska Wardani; Bangkit Riska Permata. Antibacterial Activity Test Of Extracts And Fractionsn-Hexane, Ethyl Acetate, And Pineapple Peel Water (Ananas Comosus(L.) Merr.) Against Bacteria Propionibacterium Acnes ATCC 6919. IJHET 2026, 4.