OICC Press Trends in Phytochemical Research 2588-3631 2 2 2018 06 01 Phytoconstituents profiling of Cissus rotundifolia (Forssk.) Vahl. by HPLC-MS/MS, and evaluation of its free radical scavenging activity (DPPH) and cytotoxicity 65 74 EN Ataa Said Pharmacognosy Department, National Research Centre, Dokki, 12622 Giza, Egypt Elsayed Ali Aboutabl Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr-el-Aini Street, 11562 Cairo, Egypt Farouk Rasmy Melek Chemistry of Natural Compounds Department, National Research Centre, Dokki, 12622 Giza, Egypt Gehad Abdel Jaleel Raheem Abdel Jaleel Pharmacology Department, National Research Centre, Dokki, 12622 Giza, Egypt Mona Raslan Pharmacognosy Department, National Research Centre, Dokki, 12622 Giza, Egypt Journal Article 2018 06 01 Characterization of phytoconstituents in the 70% methanolic extract of Cissus rotundifolia (Forssk.) Vahl. was performed using high-performance liquid chromatography coupled with electrospray ionization mass spectrometry. Furthermore, tandem mass spectrometry (MS/MS) was performed to assist in the structural elucidation of compounds. Twenty-seven compounds were identified. The identified compounds were four acids, sixteen phenolics, two steroidal saponins, two coumarins, two stilbenoids and one triterpene. Astragalin 1, β-amyrin 2 and 1β-hydroxy-kryptogenin-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside 3 were isolated by column chromatography and their structures were identified by spectral analysis including 1D and 2D NMR. The plant extract and the isolated compounds 1-3 were evaluated for their radical scavenging activity. Compounds 1 and 2 showed significant activity relative to that of ascorbic acid as a standard. The cytotoxicity of the plant extract, the isolated compounds and the standard doxorubicin was evaluated using the three human tumor cell lines HT116, MCF-7 and PC-3. The plant extract exhibited significant cytotoxicity against MCF-7 while showing no activity against the other cell lines. The isolated compounds 1-3 showed no activity against the used cell lines.