1 8 cineole

Triethyl citrate (purity > 98%, Merck, Kenilworth, NJ, USA), a non-sedating odourless solvent, was used to dissolve the fragrant components. Benzylacetone (purity > 95%, Tokyo Chemical Industries, Ltd., Tokyo, Japan), flumazenil (purity > 98%, Wako Pure Chemical Industries, Ltd., Osaka, Japan), diazepam (purity > 98%, Wako Pure Chemical Industries, Ltd., Osaka, Japan) and fluoxetine (purity > 98%, Tokyo Chemical Industries, Ltd., Tokyo, Japan) were used as positive controls. 1,4-Cineole (purity > 85%) was obtained from Acros Organics (New Jersey, NJ, US). 1,8-Cineole (purity > 85%) was purchased from Wako Pure Chemical Industries, Ltd., Osaka, Japan. All chemicals used were of the highest grade available.

The authentic compounds used were 1,8-cineole (Wako Pure Chemical Industrials, Ltd., Osaka, Japan), (S)-(−)-limonene (Wako), menthone (Wako), menthofuran (Extrasynthese, Genay, France), menthol (Wako), pulegone (Wako), and (E)-β-caryophyllene (Wako). An authentic chemical solution (0.19 mg mL⁻¹ 1,8-cineole; 0.02 mg mL⁻¹ (S)-(−)-limonene; 0.27 mg mL⁻¹ menthone; 0.13 mg mL⁻¹ menthofuran; 0.4 mg mL⁻¹ menthol; 0.49 mg mL⁻¹ pulegone; 0.15 mg mL⁻¹ (E)-β-caryophyllene) in 3 mL of hexane in a glass vial (4 mL) was prepared to emit VOCs that approximately corresponded to the headspace levels of major VOCs released from candy mint (4 gFW)²⁰ . Similarly, an authentic chemical solution of (S)-(−)-limonene (see above), 1,8-cineole (see above), and (R)-(−)-carvone (1.6 mg mL⁻¹, Wako) was prepared to emit VOCs that mimicked the headspace level of the VOCs from spearmint (4 gFW). A blend of authentic VOCs consisting of candy mint VOCs (1,8-cineole, (S)-(−)-limonene, menthone, menthofuran, menthol, pulegone, and (E)-β-caryophyllene) and spearmint VOCs ((S)-(−)-limonene [0.02 mg mL⁻¹], 1,8-cineole [0.1 mg mL⁻¹] and (R)-(−)-carvone) at the respective ratios corresponding to the headspace levels was also prepared in 3 mL of hexane in a glass vial. Note that germacrene D was excluded from our assays because it was not available as a pure authentic chemical.