Cytotoxic and Antioxidant Activities of Alstonia scholaris, Alstonia venenata and Moringa oleifera Plants From India

Cancer is one of the leading causes of human death. The discovery of new generations of low-cost anticancer drugs with high efficacy and low toxicity is necessary, and is only possible by screening medicinal plants with prior knowledge.
In this study, the bioactivities of three medicinal plants from India, including Alstonia scholaris, Alstonia venenata, and Moringa oleifera, were investigated.
From each plant, hexane, benzene, isopropanol, methanol, and water extracts were prepared. Cytotoxicity assays were determined by Trypan blue exclusion, MTT, and apoptotic methods. Antioxidant activities were assayed by superoxide scavenging, hydroxyl radical scavenging, and lipid peroxidation.
Among the extracts tested for cytotoxicity on DLA cells, the most active extracts from A. scholaris and A. venenata were selected (extracts from M. oleifera did not show 100% cytotoxicity even at a dose of 500 µg/mL, so it was not considered for determining EC50 value), and their EC50 values were determined. Among the extracts of A. scholaris, hexane extract of stem bark showed an EC50 value of 68.75 µg/mL, while n-hexane extract of the leaves showed a higher EC50 value of 118.75 µg/mL. A. venenata showed significant in vitro superoxide scavenging activity, superior to that of quercetin. A. venenata showed less superoxide scavenging activity. The IC50 values of hexane extract (A. scholaris), isopropanol extract (A. venenata), and quercetin were 90.5 ± 6.2, 7.5 ± 1.2, and 31.5 ± 2.5 µg/mL, respectively.
The hexane extract of stem bark from A. scholaris and isopropanol extract of leaves from A. venenata are candidate materials for the discovery of a new generation of anticancer drugs to combat diseases such as lymphoma and leukemia. These can also be used as antioxidants in dietary supplements.