Antimutagenic and mutagenic activities of some terpenes in the bacterial reverse mutation assay

The mutagenic and antimutagenic effects of linalool, linalyl acetate and β-caryophyllene were evaluated by the bacterial reverse mutation assay on Salmonella typhimurium TA 98 and TA 100, and on Escherichia coli WP2uvrA strains. Neither linalool nor β-caryophyllene showed mutagenicity, but linalyl acetate induced a statistically significant increase in the number of revertant colonies in WP2uvrA, both with and without S9 mixture. Linalool was devoid of antimutagenic activity against 2-nitrofluorene (2NF), sodium azide (SA), methyl methane sulfonate (MMS) and 2-aminoanthracene (2AA). In contrast, β-caryophyllene showed a strong antimutagenic activity against 2NF: at the maximum concentration tested (6.40 mg/plate) the number of 2NF-induced revertant colonies was reduced by 83.9%. β-Caryophyllene also showed to counteract the mutagenicity of SA (in TA 100), MMS and 2AA (in WP2uvrA): the effect was weak against SA (inhibition lower than 25%) and moderate against MMS and 2AA (up to 30.5%). The antimutagenic activity of β-caryophyllene observed here suggests further studies to evaluate its possible chemopreventive properties.