Isomahanine, carbazole alkaloid, is an antioxidative agent. Isomahanine has DPPH radical scavenging activity with an IC50 value of 24 μM[1].
References
[1] Yukari Tachibana, et al. Comparison of antioxidative properties of carbazole alkaloids from Murraya koenigii leaves. J Agric Food Chem. 2003 Oct 22;51(22):6461-7. DOI:10.1021/jf034700+