J. Cosmet. Sci., 64, 59–65 (January/February 2013) 59 The importance and perspective of plant-based squalene in cosmetology KATARZYNA WOLOSIK, MALGORZATA KNAŚ, ANNA ZALEWSKA, MAREK NICZYPORUK, and ADRIAN WOJCIECH PRZYSTUPA, Laboratory of Cosmetology, The Faculty of Pharmacy with the Division of Laboratory Medicine (K.W., M.K.), Department of Pediatric Dentistry (A.Z.), Laboratory of Esthetic Medicine, The Faculty of Pharmacy with the Division of Laboratory Medicine (M.N.), Medical University of Bialystok, and Gynecological and Obstetrical Private Clinic in Bialystok (A.W.P.), Bialystok, Poland. Accepted for publication June 6, 2012. Synopsis Squalene is a highly unsaturated hydrocarbon from triterpenoid family, discovered as a major component of the liver oil of certain varieties of deep sea sharks. In the interest of protecting biodiversity, raw materials of animal origin must be replaced by alternative sources that respect our environment. Squalene is widely pres- ent as a component of the unsaponifi able fraction of vegetable oils (i.e., olive oil, amaranth oil). Amaranth oil seems to be the key source of squalene. Amaranth grains contains 7–7.7% lipids, and these lipids are ex- tremely valuable because of the presence of ingredients like squalene, unsaturated fatty acids, vitamin E as tocopherols, tocotrienols, and phytosterols, which are not seen together in other common oils. In human skin physiology, squalene is not only used as an antioxidant, moisturizer, and material for topically applied vehi- cle, but is also used in treating skin disorders like seborrheic dermatitis, acne, psoriasis, or atopic dermatitis. Further studies on alternative sources are needed to explore the utility of squalene for treating skin. INTRODUCTION In Japan, a rich source of squalene is shark liver oil. Many Japanese people believe the shark liver oil contains powerful healing agents. Another rich source of herbal squalene is the amaranth plant, a type of grain plant that can survive in both scorching heat and ex- tremely dry soil. It produces 6-foot stalks with feathery red or magenta plumes. The Greek word “amarantus” means “never withering.” In India, the amaranth herb has been used for thousands of years. It is as rich in squalene and is as common in that region as the olive tree is in the Mediterranean basin. In the great epics of the ancient Indian cultures, Address all correspondence to Katarzyna Wolosik at katarzyna.wolosik@umb.edu.pl.

JOURNAL OF COSMETIC SCIENCE 60 this herb is believed to be empowered with immortal strength and fertility. The Sanskrit word for the plant “amaranth” means “King of Immortality.” Aztec soldiers ate a very thick soup of this herb before going to war. The amaranth plant was outlawed by Spanish missionaries who were disturbed by its association with human sacrifi ce. In fact, they believed the key to the suppression of the Aztec culture was the annihilation of the plant. The Swedish Order of the Amaranth dates back to the 1653 reign of Queen Christina. The amaranth represented distinction and honor and was formed into the “Amaranthine Wreath,” symbol of the Swedish order of the bond of fraternal friendship representing the strength and power of the plant (1). Like the Aztecs who drank a soup of amaranth, ancient warriors of Japan and China—and even the Maoris of New Zealand—were known to drink shark liver oil before leaving for war. We can, therefore, trace cultural recognition of squalene-rich products with unique survival qualities to the Mediterranean region, Scandinavian, the Indian subcontinent, the Far East, and Central America (1). Chinese healers were the fi rst to conduct prescientifi c research into a rich natural source of squalene. In 1596, Lee Ji Chin, a Chinese healer of the Ming dynasty (1369–1644), composed a 52-volume compendium of some 2000 herbs, including the liver oil of the deep sea shark. Chinese traders brought the book to Japan, where it was known as Honzo Komoku. Samurai warriors used this oil to increase their strength. Villagers of Suruga Bay on the Izu Peninsula of Japan were accustomed to drinking the same oil. The local name of this special extract was “samedawa” or “cure all.” In 1906, Dr. Mitsumaru Tsujimoto, a Japanese industrial engineer, discovered that samedawa contains extremely large quantities of an unsaturated hydrocarbon. He named the hydrocarbon squalene. Dr. Tsujimoto was presented the Imperial Award of the Japan Academy in honor of this achievement (1). SQUALENE AND ITS SOURCES Squalene is a highly unsaturated hydrocarbon from the triterpenoid family, consisting of six isolated double bonds (Figure 1). The molecule of squalene was discovered by a Japanese chemist Mitsumaru Tsujimoto as a major component of the liver oil of certain varieties of deep sea sharks. It is a low-viscous oil. When purifi ed, it is very pale yellow to colorless with almost no odor. Shark liver oil is the general and most popular source of squalene (35–80%), which is also widely present as a component of vegetable oils (2–4). Oil of olive from Olea europaea contains 0.6–0.7% of squalene, whereas amaranth (Amaranthus sp.) oil contains appreciable quantities of squalene. Depending on the variety, the oil obtained from the amaranth seeds can contain up to 8% of squalene (2,3,5). The 13% of squalene has been found as a natural constituent of human skin lipids (6). The best source of squalene is the liver of the deep sea shark (2,4,7). The last 40 years has brought a huge interest in squalene as a valuable compound in pharmacy or cosmetology fi shing on Squalus sp. went so far that some of them (i.e., Squalus acanthias, Squalus albifrons, Squalus brevirostris) are on the International Union for Conservation of Nature Red List of Threatened Species (8).