Carnosic acid, a component found within Rosemary, inhibits HIV-1 protease. - GreenMedInfo Summary
Inhibitory effect of carnosic acid on HIV-1 protease in cell-free assays [corrected].
J Nat Prod. 1993 Aug;56(8):1426-30. PMID: 8229021
Department of Biochemistry, Jozef Stefan Institute, Ljubljana, Slovenia.
In order to find new effective HIV protease inhibitors, two diterpenes (carnosic acid  and carnosol ) were isolated from rosemary (Rosmarinus officinalis L.), and rosmanol  and semisynthetic derivatives (7-O-methylrosmanol , 7-O-ethylrosmanol , and 11,12-O,O-dimethylcarnosol ) were prepared. The inhibitory activity of all six compounds against HIV-1 protease was tested. The carnosic acid  showed the strongest inhibitory effect (IC90 = 0.08 micrograms/ml). The same compound was also assayed against HIV-1 virus replication (IC90 = 0.32 micrograms/ml). The cytotoxic TC90 on H9 lymphocytes was 0.36 micrograms/ml, which is very close to the effective antiviral dose. Additionally, the tested compounds did not inhibit cellular aspartic proteases cathepsin D and pepsin at the concentration range up to 10 micrograms/ml [corrected].