80 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS in the watery phase. Both were gelatinized with bentonite 300 mesh with 10 per cent of sorbitol acting as the hurriectant. After several tests made at the Dermatologic and Esthetic School of Milan and in other beauty laboratories, the following results were obtained: (a) The best concen'trations were found to be 1 per cent of 5-furyl- hydantoin and of 3 per cent furylglycine. (b) The skin effects have been very evident for both chemicals. While the 5-furylhydantoin has a hydrating and tonifying action on the skin, the furylglycine has a clearing and smoothening effect on the skin. Both chemicals have also a remarkable "nourishing" effect on tissues. The tests through magnification revealed that the thin fissures of old and tired skins appear much less evident, while skin smoothness is increased. (c) In cream, "nourishing" treatments and other cosmetics containing additional skin active constituents, the skin health improvement results are even more evident. (d) Neither incompatibility nor allergy have been noticed up to now from the use of these two chemicals. (e) The tests on the toxicity of the two chemicals have given results similar to those of the normal amino acids. Consequently, their use appears harmless. SUMMARY In accordance with the tests carried out by us, $-furylhydantoin and furylglycine have proved to be et•caciously active products for the skin. Furylhydantoin (liposoluble) is different in its action from furylglycine because of its major hydrating power, while the amino acid has a marked action in minimizing skin lines. Both products have a remarkable "nourishing" and "regenerating" action. In view of the low cost convenience of these products, we feel certain that they can find wide application in cosmetics. REFERENCES (1) Ciocca, B., Rovesti, P., and Roccheggiani, G., "Azi0ne cutanea di a[cu•i •uovi ami•o-acidi a[icidici di $i•te$i." Presented at the XII International Congress ooe Esthetics and Cos- metology held in Venice, May, 1958. To be published. (2) Fischer, Albert, "Die Bedeutung d. Aminosauren F. die Gewebezellen in vitro," Acta Phys. Scand., 143 (1941). (3) Dunlop, A. P., and Peter, F. N., "The Furans," Monograph Series 119, New York, The Reinhold Publishing Co. (1953), p. 598. (4) Harvill, E. K., and Herbst, R. M., •. Org. Chern. 9, 21 (1944). (5) Henze, H. R., and Speer, R..[., •. Am. Chem. $oc., 64, 522 (1942). (6) Hermann, G., Kosrnetik-Parfurn-Drogen Rundschau, 9/10 (1956). (7) Hermann, G., Ibid., 3/4 (1957).

THE INTERFERENCE OF NONIONIC EMULSIFIERS WITH PRESERVATIVES VIII By JOHANNA POPRZAN and MAISON G. DENAVARRE Presented September 18, 1958, International Symposium, Gesellschaft Deutscher Kosmetik Chemiker, Bonn, Germany IN THE COURSE of investigating the inactivation of preservatives by nonionic surfactants, a number of significant developments were noted but hitherto not published. In addition other progress has suggested new lines of research in this unsolved problem. Indeed, the recent report (1) that 3 per cent hexylene glycol was used successfully with 0.2 per cent sorbic acid to preserve a nonionic product has led us to re-examine some earlier results (1955) and to further examine the effect of all commonly used glycols along with other polyols. Propylene glycol had been used as a solvent for preservatives in one of our (M. G. deN.) early experiments. Checking the glycol controls led to the verification of the established inhibitory concentration for propylene glycol against/Ispergillus niger. This was found to be at least 16 per cent, in Jaag medium, with or without the presence of the nonionic G-3720. This figure is somewhat higher than the published concentrations recom- mended. However, when the glycol, 0.1 or 0.2 per cent methyl p-hydroxy- benzoate and 2 per cent G-3720 were added to Jaag medium, there were in- dications that somewhat less than 10 per cent propylene glycol would have either a potentiating effect on the preservative, or that it might interfere with the suspected complexing of the preservative with the nonionic. With this background, one of us (J.P.) set up experiments to evaluate the effect of position and number of hydroxyl groups on a polyol in pre- venting inactivation ofmethylp-hydroxybenzoate by nonionics. Experimental. The microSrganisms used in this series were Proteus vulgaris, Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli and /Ispergillus niger. Nutrient broth was the bacterial medium while Czapek Dox medium was used for the mold. The test Inethods and other procedures were the same as one of us had previously published (2). * Cosmetic Laboratories, Inc., Div. of Beauty Counselors, Inc., Detroit 7, Mich. 81