30 JOURNAL OF COSMETIC SCIENCE 70000 a 11 16 F"ID o.:.o.o MTn• 0- 0 3D b 0 12000 Time (min) a a soooo b M=683 a 370 40000 I 443 I M-C"2OTMS M-15 Figure 3. High-polarity compounds. (a) TLC-FID chromatogram of the p-TLC fraction A. Compound identification: 10, 11, cholesterol derivatives 12, ceramide type II 13, (7)-hydroxycholesterol 14, ceramide type VI 15, hydroxyacids and diols 16, cholesterol sulphate. The chromatogram has been scaled in order to see the minor compounds. (6) Mass spectra obtained in electron impact GC-MS of ceramide Type II with a 16-carbon acidic moiety and a dihydrosphingosine basis. 528 for the hydroxyacids, and from 374 to 514 for the diols. Even-carbon membered compounds were predominant, with a maximum at C 16 . Medium-polarity lipids In the medium-polarity-range lipids, obtained from fractions D to H, free fatty acids and alcohols, either aliphatic or steroidal, were identified. Free fatty acids present in fractions E (Figure Sa), F, G, and H were identified by the diagnostic ion [O + =COSi(CH 3 ) 3 } (m/z 117). Their molecular weights varied from 216 to 566, showing a bimodal distribution with two maxima at C 16 and C2 7 . This profile may be indicative of the coexistence of two different enzymes, carrying out their bio- synthesis. In this way, one of them is responsible for the monomodal distribution of the

8 7 6 _s a4 E -3 2 0 ANALYSIS OF WOOL-WAX EXTRACT 16 18 20 chain length 22 Iii Sphingosine □ Dihydrosphingosine 24 Figure 4. Quantification at a molecular level of the ceramides II (mg/g) of wool-wax extract. b 35 30 25 6 a Time ( (min) 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 chain length 31 Figure 5. Medium-polarity compounds. (a) TLC-FID chromatogram of the p-TLC fraction E. Compound identification: 5, free acids 6, alcohols 7, sterols. (b) Quantification at a molecular level of the fatty alcohols (mg/g) of wool-wax extract. medium-chain fatty acids and the other for the monomodal distribution of the long- chain fatty acids (26). Fatty alcohols present in fractions D, E, F, and G were characterized by [M-CH 3 r and [CH 2 =O + Si(CH 3 ) 3 } (m/z 103). Their molecular weight ranged from 258 to 566. They