Solanum lycopersicum L. is an annual herb, member of family Solanaceae; this plant is native to America.

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1 Tomato BOTANY Solanum lycopersicum L. is an annual herb, member of family Solanaceae; this plant is native to America. Tomato plant has decumbent stems, which bend under the weight of secondary branches, leaves and fruits; therefore, these plants usually grow on other plants or structures. Tomato stems and leaves are covered with hairs (trichomes). The leaves are cm long, pinnate, composed of 5-9 leaflets each leaflet 8 cm long), margins serrate. The stem and leaves are highly vascularized. The first 30 cm of roots are densely ramified. This root system is called tap root. Tomato flowers are hermaphrodite, 1-2 cm, with five lobed corollas, bright yellow in almost every tomato species; they appear in clusters of 3 to 12 flowers, separated by 3 leaves. S.lycopersicum is grown worldwide because of its edible fruits, known as tomatoes. These fruits are slightly acid and brightly-colored berries, color ranging from yellowish to red, due to the presence of pigments lycopene and carotene. Wild tomatoes are 1-2 cm in diameter; cultivated varieties are much larger. This fruit contains a large number of seeds, embedded in a slimy jelly-like pulp. The pulp contains much water and is very tasty and easy to eat. Tomato plants thrive in fertile, humid, organic soils. Tomato extract is produced from the fruits of Solanum lycopersicum L. V 04-01/ ,

2 CHEMISTRY Besides water, the major constituents of tomatoes are carbohydrates which give tomatoes a slight sweetness and some organic acids, which give them a typical taste. Citric and malic acids are the most abundant acids, although some other acids such as acetic, formic, lactic and fumaric have been found. Tomato is a major source of certain minerals such as potassium and magnesium. Vitamins in tomatoes include: vitamin C, thiamin (vitamin B1) and nicotinic acid (vitamin B3). This fruit also contains carotenoids such as lycopene (a pigment that gives tomato its typical red color); flavonoids and other polyphenols such as naringenin and quercetin; and p-coumaric, caffeic, ferulic and chlorogenic acids. Constituents Content (per 100 g) Water (g) 94.7 Protein (g) 1.0 Fat (g) 0.1 Fiber (g) 1.6 Carbohydrates (g) Glucose 0.9 Fructose 1.0 Organic acids (g) Citric 0.43 Malic 0.08 Vitamins (mg) Vitamin C 18 Thiamin 0.04 Riboflavin 0.02 Nicotinic acid 0.7 β-carotene (equivalent) 0.34 Minerals (mg) Potassium 200 Sodium 6 Calcium 8 Magnesium 10 Iron 0.3 Zinc 0.2 Table 1. Chemical composition of tomato (Madhavi & Salunke, 1998). V 04-01/ ,

3 TRADITIONAL USES Tomato is widely used in cosmetics, especially in home treatments, as a cleansing, refreshing and revitalizing agent. It is used to reduce eye bags, an action attributed to tomato s vitamin C and flavonoids (the later compounds strengthen blood capillaries). Tomato has been attributed skin cleansing and rejuvenating properties. It is included in face masks aimed at removing dead cells, because it contains α-hydroxyacids. It is also habitually used to soothe the skin after sunbath and to heal wounds and sores. COSMETIC PROPERTIES Humectant activity and regulation of transepidermal water loss (TEWL) This activity is due to the carbohydrate, α-hydroxyacids (AHA) and vitamin contents of tomato. Carbohydrates are active principles extensively used in cosmetics. Monosaccharides are hygroscopic, namely they adsorb water thus contributing to keep a healthy moisture level in the horny layer. Oligosaccharides have the same property. These active compounds build hydrogen bonds, prevent massive water loss and reduce dehydration. Additionally, some of these compounds make a protective coat on the skin, thus preventing and slowing down transepidermal water loss. AHAs are a special group of organic acids, which have a hydroxyl group on carbon of the molecule. This group includes: citric, malic, glycolic, lactic, pyruvic and other acids, which can be found in a number of natural products such as fruits and vegetables. AHAs are being used in cosmetics since the nineties, and number of efficacy tests supports the cosmetic and dermatological applications of these compounds (Kale PN. & Adsule PG., 1995). These active principles reduce inter-corneocyte junctions, soften intercellular cement and facilitate exfoliation. At lower concentrations, they facilitate moisturizing, at higher concentrations, they act as exfoliating agents. AHA s chemical structure, with several hydroxyl groups, allows for higher water absorption and retention power. In this way, these hygroscopic compounds enhance skin moisturizing and strengthen the skin barrier function (Carbajo Espejo JM et al, 2004). Thus, tomato extract is recommended to formulate cosmetic products with moisturizing action. V 04-01/ ,

4 Stimulation of corneocyte turnover This activity is due to the α-hydroxyacids (AHA) content in tomato. AHAs act at the horny layer level. These acids act on corneocyte cohesion in the deepest skin layers, thus promoting turnover in the horny layer and enhancing flexibility in the skin surface. This action was discovered when the effects of topical treatments with AHAs on ichthyoids was being studied. AHAs were also found to affect any hyperkeratinization process (Van Scott E.J. et al., 1984). The mechanism of action of these acids is not fully understood. Different theories have been proposed to explain their action. The earliest theory proposes that AHAs impairing effects on corneocyte cohesion is mainly due to their action on intercellular ionic bonds (Berardesca E. & Maibach H., 1995). Corneocytes are bound together through covalent (disulfide bonds) and non-covalent bonds; the later ones include ionic bonds, established between negatively charged groups (such as phosphate, sulphate, carboxyl) and positively charged groups (amine groups). AHAs effects would thus be based on their ability to inhibit certain enzymes involved in the formation of phosphate and sulphate groups in the cellular walls. AHAs might compete with sulphate and phosphate for the sulphotransferase and phosphotransferase enzymes, which are involved in the formation of mucopolysaccharides, phospholipids, sterols and glycoproteins. Some AHAs inhibit certain phosphotransferases and specific kinases. For example, citric acid inhibits the glucose-6-phosphotransferase and the phosphofructokinase enzymes. Additionally, AHAs may also act as substrates that accept phosphate groups, yielding phosphorylated alpha-hydroxyacids in certain metabolic pathways. More recently, Wang (1999) proposed another model to explain their action mechanism. AHAs have been observed to act on calcium, which is essential to build most of the intercellular joints and to maintain their structural integrity. It has been found that AHAs reduce the calcium concentration in the epidermis and that calcium gets eliminated from the intercellular joints by chelation. The resulting drop in calcium concentration brings about cellular decohesion and desquamation. This effect is reinforced by the action of epidermal proteolytic enzymes. Thus, tomato extract is recommended to formulate cosmetic products with exfoliating action. V 04-01/ ,

5 Antioxidant action Because of its phenolic compounds, vitamin C and nicotinic acid contents, tomato is an antioxidant vegetable, which can neutralize free radicals and provide defense against cell structures degradation. Phenolic compounds exert their antioxidant action in different ways (Beltrán, I., 2003): By scavenging free radicals and reducing the generation of these compounds. By their ability to inhibit, activate or protect specific enzymes in the organism. By reducing the consumption of own antioxidants like vitamin E and carotenoids. Vitamin C is a powerful antioxidant with radical scavenging activity, very useful in the treatment of photoaging. This vitamin has photoprotective properties similar to those of vitamin E, and it is able to neutralize free radicals generated by UVB radiation. Studies evidenced reduction of UV-induced erythema after a treatment with vitamin C, alone or in combination with vitamin E (Chiu A. & Kimball AB., 2003). Nicotinic acid also has antioxidant activity. Studies report beneficial effects of topical nicotinic acid for prevention of skin collagen loss associated to photoaging, and for reduction of acne problems. Recent studies report novel beneficial actions for topical nicotinic acid on aged skin, such as enhancement of the skin barrier function, reduction of photoaging signs (spots, redness, etc) and reduction of sebum production (Bissett D.L. et al., 2004). Thus, Tomato extract is useful to formulate cosmetic products for the protection of skin and hair against oxidative processes. V 04-01/ ,

6 COSMETIC APPLICATIONS Action Active Cosmetic application TEWL regulation Carbohydrates AHA Vitamins Moisturizing Cell renewal stimulation AHA Exfoliant Antioxidant Phenolic compounds Vitamins Anti-aging Photoprotection Hair color protection RECOMMENDED DOSE The recommended dose is between 0.5% and 5.0%. BIBLIOGRAPHY Beltrán, I. Polifenoles y xantinas: su aplicación en obesidad. Acvtividad Dietética, 2003; 19: Berardesca E. & Maibach H. AHA mechanisms of action. Cosmetics Toiletries, 1995; 110 (6): (ref. 1327). Bissett D.L. et al. Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin. Int J Cosmet Sci, 2004; 26: Carbajo Espejo JM, Ruiz manso R, del Tío Moreno R. Hidratación cutánea (y II). AULAdelafarmacia, 2004 p: Chiu A. & Kimball AB. Topical vitamins, minerals and botanical ingredients as modulators of enviromental and chronological skin damage. Br J Dermatol., 2003; 149: Kale PN. & Adsule PG. Citrus In Handbook of Fruit Science and Technology. Production, Composition, Storage, and Processing. New York: Marcel Dekker, Inc., 1995; (ref. 641* SAL). Madhavi & Salunkhe Tomato In Handbook of Vegetable Science and Technology. Production, Composition, Storage, and Processing. New York: Marcel Dekker, Inc., 1998; p: (ref. 641* SAL). V 04-01/ ,

7 Van Scott EJ, Yu RJ. Hyperkeratinization, corneocyte cohesión, and alpha- hydroxy acids.j. Am. Acad. Dermatol. 11, , Wang X. A theory for the mechanism of action of the -hydroxy acids applied to the skin. Medica Hypotheses, 1999; 53 (5): (ref. 4261). V 04-01/ ,