Totarol is a diterpene originally isolated from P. totara that has diverse biological activities, including antibacterial, antioxidant, and neuroprotective properties.¹ It is active against Gram-positive bacteria, including P. acnes, S. mutans, B. subtilis, and B. ammoniagenes (MICs = 0.39, 0.78, 1.56, and 0.78 µg/ml, respectively), as well as penicillin-resistant and -susceptible strains of S. aureus (MICs = 0.78 and 1.56 µg/ml, respectively).² It inhibits mitochondrial respiration in P. aeruginosa, inhibiting NADH-cytochrome c, NADH-DPIP, and NADH-coenzyme Q reductases but not cytochrome c oxidase.³ Totarol inhibits Fe(III)-ADP/NADPH-induced lipid oxidation in rat liver microsomes and mitochondria (IC50s = 4.79 and 0.47 µM, respectively) and autooxidation of linoleic acid with an IC50 value of 9.8 µM.⁴ In rat primary cerebellar granule cells, totarol increases Akt and GSK-3β phosphorylation when used at a concentration of 5 µM and prevents neuronal death induced by glutamate or oxygen and glucose deprivation.⁵ It also reduces infarct volume in a rat model of acute cerebral ischemic injury when administered at doses of 1 and 10 microgram/kg.