Embelin is a benzoquinone that has been found in E. ribes and has diverse biological activities.¹ It inhibits viral replication of the influenza A subtype H1N1 and the influenza B subtype Victoria-like in MDCK cells (IC50s = 0.3 and 0.2 µM, respectively).² It is also an inhibitor of X-linked inhibitor of apoptosis (XIAP; IC50 = 4.1 µM in a fluorescence polarization assay).³ Embelin (20-50 µM) induces apoptosis and increases caspase-9 levels in PC3 prostate cancer cells. It completely inhibits TNF-α-induced NF-κB and IκB kinase (IKK) activation and inhibits TNF-α-induced IκBα phosphorylation in KBM5 human myeloid cells when used at a concentration of 50 µM.¹ It is active against the Gram-positive bacteria B. subtilis, S. aureus, and M. luteus (MICs = 20, 20, and 25 µg/ml, respectively) and the Gram-negative bacteria P. aeruginosa, K. pneumoniae, and E. coli (MICs = 25, 25, and 45 µg/ml, respectively).⁴