Phytochemical investigations of Dovyalis caffra (leaves and twigs) revealed a new dovyalicin-type spermidine alkaloid, named Dovyalicin G (1); which was identified as (E)-N-(4-(1,5-diazocan-1-yl)butyl)-N-methyltetradec-2-enamide, along with previously isolated β-sitosterol (2) and Hentriacontan-1-ol (3). The structures were established using ESI/MS, EI/MS, ¹H NMR, APT NMR, and two-dimensional NMR experiments. In addition to the biological studies of the different plant extracts including cytotoxicity, topoisomerase II inhibition, antimicrobial, and in-vitro anti-inflammatory activities. Screening of 5-lipoxygenase (5-LOX) and Cyclooxygenase-1 (COX-1) and -2 (COX-2) inhibition to evaluate anti-inflammatory activity were performed. The alkaloid fraction showed good antimicrobial activity against studied microorganisms and remarkable cytotoxic activities against studied cell lines (Besides, total methanolic and petroleum ether extracts). The total methanolic extract showed strong COX- inhibition activity and selectivity toward COX-2, comparing with celecoxib.