The phytochemical examination of the stem bark and leafy branches of Ulmus pumila L. gave rise to the separation of 13 compounds, recognized as Friedelin, 3β-acetoxyurs-11-en-13β, 28-olide, 3β-O-acetyl ursolic acid, 3β-O-acetyl oleanolic acid, β-sitosterol, stigmasterol, betulinic acid, methyl ursolate, methyl oleanolate, kaempferol-3-O-rutinoside, quercetin-3-O-β-D-glucopyranoside, quercetin-3-O-β-D-galactopyranoside, and caffeic acid. Their structures were elucidated using chemical and spectroscopic methods (ultraviolet, Infrared, EI-MS, 1 H-NMR, and 13 C-NMR) and by comparison with literature data. The cytotoxic potential of the crude methanol extract of the stem bark, besides the isolated triterpenoids, was tested against five human carcinoma cell lines, namely human colorectal carcinoma (HCT-116), human breast adenocarcinoma (MCF-7), human hepatocellular carcinoma (HepG2), human osteosarcoma (HOS), and human pulmonary adenocarcinoma (A549) cell lines. Betulinic acid exhibited a cytotoxic potential against MCF-7, HCT-116, and A549 cell lines with half maximal inhibitory concentration (IC 50 ) values equal to 22.39 ± 0.09 μM, 22.29 ± 0.05 μM, and 42.33 ± 0.06 μM, respectively. Meanwhile, the remaining triterpenoids showed a cytotoxic potential against HCT-116 and MCF-7 cell lines, with IC 50 values ranging from 48.91 ± 0.12 to 78.98 ± 0.07 μM. The demonstrated cytotoxic potential of betulinic acid suggests its use as a lead compound for anticancer therapy.
