QUANTITATIVE ANALYSIS OF BERGAPTEN 255 o .6• .o• .o• .6, j CONCENTRATION gm•o • 5-- MOP •l 8- MOP - Figure 4. The effect of increasing concentrations of 5-MOP and 8-MOP on the diameter of the killing zones of the yeast (Mean _+ S.E.M.) 5-MOP is noted to be more photoactive than 8-MOP and its dose- response curve is similar to that of bergamot oil .i '""'" i :5 • • " • -- • .- = . . _.• Figure 5. The results of the phototoxic effects of the bergapten TLC fraction of 0.25, 0.5 and 1% bergamot oil and Yves Saint Laurent toilet water

256 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS obtained in the irradiated cultures and the inhibition induced by 5-MOP was significantly greater than that of 8-MOP. The Concentration of 5-MOP in Perfumes. The 5-MOP content of a total of 108 perfumes was determined. Taking YSL toilet water as an example, the killing zones ob- tained with 5/xl of 0.25, 0.5 and ! % bergamot oil and a similar volume of YSL toilet water are shown in Figure 5. It is noted that the clear zone obtained with YSL toilet water is slightly smaller than that of 1% bergamot oil. To determine, therefore, the exact concentration of bergamot oil in this toilet water the experiment was repeated us- ing 5 /xl of 0.5, 0.75 and 1% bergamot oil and the toilet water. The clear zone produced by the toilet water was greater than that of 0.75 % and less than that obtained with ! % bergamot oil, indicating that YSL toilet water contains 0.75 to 1% bergamot oil. The concentration of 5-MOP would therefore be 0.00203 to 0.00270 g%. A similar approach was used in the determination of the concentration of bergamot oil in the remaining perfumes. The test was most accurate when quantities of bergamot oil smaller than 0.1/xl (0.27/xg 5-MOP) per TLC spot were used. Normal growth was ob- tained in all control plates. The 5-MOP content of a total 108 perfumes tested is shown in Table IV. The concentrations ranged from 0.00004 to 0.01080% (0.016 to 4% Table IV The 5-MOP Content of Random Samples of Perfumes as Determined By the Candida Albicans Phototoxicity Test and the Estimated Bergamot Oil Equivalent Based Upon a 5-MOP Concentration of 0.27 g/100 ml Bergamot Oil (Coty) Manufacturer Perfume Estimated Bergamot Equivalent Based Upon 0.27 g]100 ml 5-MOP (ml/100 ml) Estimated 5-MOP Concentration (g/100 ml) Avon Charisma Cologne Deep Woods Aftershave Elegance Cologne Field Flowers Cologne FleurD'Avon Cologne Nearness Cologne New World Aftershave Oland Aftershave Promise of Heaven Cologne Roses Roses Cologne Tai Winds Aftershave Unforgetable Cologne Wind jammer Aftershave Balenciaga Ho Hang Toilet Water Le Dix de Balenciaga Quadrille Perfume Balmain Miss Balmain Perfume Boots Boots 7 IF Cologne Jade East Aftershave Caron Bellodgia Perfume Caryen Variation Perfume Chanel Chanel Aftershave Chanel 5 Cologne Chanel 5 Perfume Chanel 19 Perfume 0.062 to 0.125 0 0 0 0 0 0 0 0 0 0 0.016 0 0.016 0.016 4 0.25 to 0.5 0.5 O.25 0 O.25 0 O.75 0.016 0.125 to 0.25 0.00017 to 0.00034 0 0 0 0 0 0 0 0 0 0 0.00004 0 0.00004 0.00004 0.0108 0.00068 to 0.00135 0.00135 O. OOO68 0 O. OOO68 0 0.00203 0.00004 0.00034 to 0.00068 (Continued on Page 257.)