JOURNAL OF COSMETIC SCIENCE 524 Figure 4. Typical chromatograms (on RP-4) of hinokitiol in hair restorer, skin lotion, and body soap. (A) 240 nm (B) 345 nm. (1) Hair restorer (2) skin lotion (3) body soap. The tested samples were diluted with water as described in “Procedures.” Arrowed peak: hinokitiol. and 16.0 μg) was added to the hair restorer (0.50 ml 0.268 mg at 240 nm and 0.251 mg at 345 nm), the skin lotion (10 ml 78.1 μg at 240 nm and 80.2 μg at 345 nm), and the body soap (0.10 g 18.2 μg at 240 nm and 17.8 μg at 345 nm), respectively. The mixtures were diluted and analyzed. As shown in Table III, the recovery values were satisfactory (92.4–104.8%). These results indicate that our method is capable of measuring hinokitiol concentration in hair restorers, skin lotions, and body soaps. Table III Recovery of Hinokitiol in Hair Restorer, Skin Lotion, and Body Soap Samples Recovery (%, mean ± S.D., n = 5) Hair restorer At 240 nm 102.2 ± 6.8 At 345 nm 104.8 ± 6.6 Skin lotion At 240 nm 96.4 ± 6.3 At 345 nm 95.0 ± 6.2 Body Soap At 240 nm 92.4 ± 5.3 At 345 nm 94.6 ± 5.5

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