(+)-Borneol is a bicyclic monoterpene and a stereoisomer of (–)-borneol that has been found in various plants, including S. tomentosa, and has diverse biological activities including analgesic, neuroprotective, antioxidant, and antimicrobial properties.1,2,3,4 (+)-Borneol is a positive allosteric modulator of α1β2γ2L subunit-containing GABAA receptors (EC50 = 248 μM for human recombinant receptors).1 It dose-dependently increases the paw withdrawal threshold following segmental spinal nerve ligation surgery or intraplantar injection of complete Freund's adjuvant (CFA) in mouse paw.2 (+)-Borneol (100 μM) inhibits increases in reactive oxygen species (ROS) levels and cytotoxicity in SH-SY5Y neuroblastoma cells incubated with amyloid-β (1-42) .3 It also inhibits the growth of Gram-positive and Gram-negative bacteria in vitro, including E. coli, S. aureus, P. aeruginosa, P. vulgaris, and S. typhimurium (MICs = 125-250 μg/mL).4 Formulations containing (+)-borneol have been used as fragrance ingredients.
1.Granger, R.E., Campbell, E.L., and Johnston, G.A.R.(+)- And (–)-borneol: Efficacious positive modulators of GABA action at human recombinant α1β2γ2L GABAA receptorsBiochem. Pharmacol.69(7)1101-1111(2005) 2.Jiang, J., Shen, Y.Y., Li, J., et al.(+)-Borneol alleviates mechanical hyperalgesia in models of chronic inflammatory and neuropathic pain in miceEur. J. Pharmacol.75753-58(2015) 3.Hur, J., Pak, S.C., Koo, B.S., et al.Borneol alleviates oxidative stress via upregulation of Nrf2 and Bcl-2 in SH-SY5Y cellsPharm. Biol.51(1)30-35(2013) 4.Tabanca, N., Kirimer, N., Demirci, B., et al.Composition and antimicrobial activity of the essential oils of Micromeria cristata subsp. phrygia and the enantiomeric distribution of borneolJ. Agric. Food Chem.49(9)4300-4303(2001)