TECHNOLOGICAL ASPECTS OF LANOLIN 243 cholesterol," and inactive alcohols. Only two true sterols have been found, namely, cholesterol and di- hydrocholesterol. Windaus and Tschesche (6) reported that the so- called "Isocholesterol" consisted of 92 per cent lanosterol and 8 per cent agnosterol and these are triterpene- like alcohols rather thafi sterols. However, Ruzicka, et al., (7,'8, 9) found two more alcohols, dihydro- lanosterol and dihydro-agnosterol. Furthermore, Ruzicka proved that lanosterol and dihydrolanosterol are identical with kryptosterol and di- hydrokryptosterol. These four al- cohols obtained from the so-called Isocholesterol fraction each have 30 C atoms. They have the same C skeleton, the hydroxyl group in the same position, but differ in the number and position of the double bonds. Double Melting Bonds Point, øC. Lanosterol (C•0H•00) 2 140.5-141.5 Dihydrolanosterol (C•oH•20) 1 144.5-145.5 Agnosterol (C•oH4•O) 3 163.5-164.5 Dihydroagnosterol (C•0H•oO) 2 156-157 The two double bonds of lano- sterol are not conjugated. The one that is easily reduced is found in the side chain. Agnosterol has three double bonds. Two are found in different rings but are conjugated while the third double bond is in the side chain and it is this one that is easily reduced. Since it is a known fact that pure lanolin does not develop rancidity, it must mean that even when these double bonds are oxidized no odor develops. ' Despite the extensive literature relating to lanolin and its use in water-in-oil emulsions, there is no agreement as to the particular property which is responsible for its ability to absorb water. Many have attributed the power to the cholesterol content. Powers, et al. (10), found that the emulsifying efficiency of cholesterol is much less than the emulsifying efficiency of mixtures of cholesterol and choles- terol esters when used ,with pet- rolatum for the purpose of emulsify- ing water. Most of the literature relating to emulsification of lanolin or of its liberated fractions reports results obtained after dilution with mineral products. Therefore, an investiga- tion was undertaken to determine if possible, the effect of cholesterol in free and combined form on the water absorption of lanolin. Commercial samples of lanolin were obtained which were refined in various ways from each one of the methods described for the recovery of wool grease. It was felt that the method of recovery might,have an effect on the water absorption pow. er and that all types of fanolin should be investigated. The free, com- bined, and total cholesterol contents were determined (11). The alcohol fraction for the determination of the total cholesterol content was ob- tained (12) through pressure saponi- fication with alcoholic alkali for sixteen hours. The British Pharmacopoeia

244 JOURNAL OF THE SOCIETY' OF COSMETIC CHEMISTS method of determining the choles- terol content must not be taken as the actual chole: terol content but as the percentage of alcohols which will be precipitated with digitonin and calculated as cholesterol. Gard- ner, et al. (13), tabulate some of the alcohols which also give precipitates with digitonin and which may be present in the free or combined alcohols of lanolin. Windaus (14) also tabulates the relative solubili- ties of digitonides. Anderson (15) states that if cholesterol is formed from plant sterols, a number of dif- ferent as well as isomeric choles- Contrary to popular belief the benefits derived from lanolin are not centered about the properties of the individual fatty acids or alcohols present. The water absorption and emollient properties of lanolin are due to the composition of the mix- ture. This mixture, which we call lanolin, is essentially a chemical combination of fatty acids and alcohols in ester form. No evidence has been published to show that any chemical individual contained in the mixture is entirely or partly re- sponsible for the properties of lanolin. TABLE I Anhydrous Lanolin, U.S.P. Sample No. Free Cholesterol, % Unsaponi- fiable or Total Alcohols, % Cholesterol of Total Alcohols, % Combined Calculated Cholesterol Water Total by Absorp- Cholesterol, Difference, tion, % % % 1 2 3 4 5 6 7 8 9 10 11 12 20 24 18 14 26 19 1.9 1.8 2.8 5.5 2.5 1.7 43.8 42.1 43.1 43 .l 45.3 47.0 45.9 46.9 48.7 46.0 44:. 3 40.7 26.1 26.8 32.1 26.8 27.8 37 5 30 1 28 4 30 0 31 4 30 5 27 2 11.4 9.4 350 11.3 8.9 370 13.8 12.0 460 11.6 10.2 4:60 12.6 10.0, 470 17.6 15.7 480 13.8 11.9 490 13.3 11.5 500 14:.6 11.8 520 14.4 8.9 530 13.5 11.0 540 11.1 9.4 560 terols m•ht be expected to occur in animal fats and waxes, correspond- ing to the various phytosterols con- tained in the plant material which serves as food. Therefore, the results listed are only relative in relation to the cholesterol content. From the results obtained there is no indication that the free, com- bined, or total cholesterol has any effect on the water absorption power of lanolin. BIBLIOGRAPHY (1) Barker, S. G., "Wool Quality," Wool Industries Research Assn., Great Britain (1931). (2) U.S. Pharmacopceia, XIII, Mack Print- ing Co., Easton, Pa. (Apr. 1, 1947). (3) Weitkamp, 5'. vim. Chem. $o% 67, 447 (1945). (4) McConnell, John E. W., "Antioxidants in Vegetable Oils," vim. Perruiner Es- sent. Oil Rev. (Sept., 1947). (5) Lewkowitsch and Warburton, "Oils, Fats & Waxes," Vols. I, II, & III, 6th edition, Macmillan & Co. Ltd., London (1922). (6) Windaus and Tschesche, Z. PhysioL Chem., 191, 55 (1930).