Seselin is an angular pyranocoumarin that has been found in M. semecarpifolia and has diverse biological activities.1,2,3,4 It is cytotoxic to P388 and HT-29 cells in vitro (EC50s = 8.66 and 9.94 μg/ml).1 Seselin (0.5, 4.5, and 40.5 mg/kg) reduces acetic acid-induced writhing in mice.2 It also reduces paw licking in the first and second phases of the formalin test in mice when administered 30 minutes prior to formalin. Seselin (3, 10, and 30 mg/kg) decreases serum levels of IL-1β, IL-6, and TNF-α in a mouse model of sepsis induced by cecal ligation and puncture and increases survival when administered at a dose of 30 mg/kg.3 It reduces ear edema induced by phorbol 12-myristate 13-acetate in mice (ED45 = 0.25 mg/ear).4

|1. Chou, H.-C., Chen, J.-J., Duh, C.-Y., et al. Cytotoxic and anti-platelet aggregation constituents from the root wood of Melicope semecarpifolia. Planta Med. 71(11), 1078-1081 (2005).|2. Lima, V., Silva, C.B., Mafezoli, J., et al. Antinociceptive activity of the pyranocoumarin seselin in mice. Fitoterapia 77(7-8), 574-578 (2006).|3. Feng, L., Sun, Y., Song, P., et al. Seselin ameliorates inflammation via targeting Jak2 to suppress the proinflammatory phenotype of macrophages. Br. J. Pharmacol. 176(2), 317-333 (2019).|4. GarcÍa-ArgÁez, A.N., RamÍrez Apan, T.O., Parra Delgado, H., et al. Anti-inflammatory activity of coumarins from Decatropis bicolor on TPA ear mice model. Planta Med. 66(3), 279-281 (2000).