Hamamelis virginiana L., commonly known as witch hazel, belongs to the Hamamelidaceae family.

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1 Hamamelis BOTANY Hamamelis virginiana L., commonly known as witch hazel, belongs to the Hamamelidaceae family. It is a small tree or shrub that grows between 1.5 and 3.5 m in height. The bark is brown and smooth. The leaves are deciduous, elliptic to ovate, margins wavy, asymmetrical at the base, between 7.5 and 12.5 cm long. They are almost odourless and have an astringent, mildly bitter, aromatic taste.the flowers are yellow outside and yellowish brown inside, with four characteristic thread-like, about 2 cm long petals. Blooming occurs by the end of autumn, when the leaves fall. The fruit is a capsule. Hamamelis is native to North America, where it often grows in the damp forests of the South-eastern areas (from Brunswick and Quebec until Minnesota, south of Florida, Georgia, Louisiana and Texas). It is cultivated in the United States and Canada. In Europe, cultivation is at the small scale, especially as an ornamental bush for gardens. The leaves must be harvested in summer. Hamamelis extract is produced from the leaves of Hamamelis virginiana L. V 06-04/ ,43000,43010,43020,43040,43050,43080,

2 CHEMISTRY Leaves Tannins The proportion of tannins is between 3 and 10% of total composition. They are a combination of gallic tannins, condensed catechols, procyanidols and hydrolysable tannins (hamamelitannins). Figure 1. Hamamelitannin (gallic acid and D-hamamelose units) (Alonso, J., 2004). Hydrolysable tannins are oligo- or poly-esters of a sugar (or a related polyol) and a variable number of phenol acid molecules. The sugar is, generally, glucose. The phenol acid is either gallic acid (these are called gallic tannins) or hexahydroxydiphenic (HHDP) acid and its oxidation derivatives (these are called ellagic tannins). Condensed tannins or proanthocyanidols are flavan polymers. They are made up of flavan-3-ols units attached one to each other by carbon-carbon bonds, generally 4 8 or 4 6, which result from the attachment between the electrophilic C-4 of a flavanyl (that comes from a flavan-4-ol or a flavan-3,4-diol) and a nucleophilic position (usually C-8 and less frequently C-6) of another unit, generally flavan-3-ol (Bruneton J., 2001). Essential oil Essential oil is %. It is rich in alcohols (40%), esters (15%) and carbonyl compounds (25%). Other active principles Leucoanthocyanidins, flavonoids (myricetin, quercetin, kaempherol and astragalin), phenolic acids (quinic acid, caffeic acid and gallic acid), choline ( %), oxalic acid and unidentified bitter substances. V 06-04/ ,43000,43010,43020,43040,43050,43080,

3 Flowers Flavonoids Lato sensu flavonoids are pigments almost universally present in vegetables. Almost always watersoluble, they are responsible for the colour of flowers, fruits and some times, leaves. All flavonoids more than 4,000 come from a common biosynthetic origin and therefore share the same basic structural element, namely a 2-phenylchromane skeleton. Due to this structural homogeneity, a large number of substances are included under this name. Thus, instead of referring to flavonoids lato sensu, it is advisable to separate them on the basis of their behaviour and particularities into: flavan derivatives, anthocyanosides and isoflavones, and keep the term flavonoids strictu sensu for flavones, flavonols, their 2,3-dihydro derivatives, their dimers and the yellow flavonoids: aurones and chalcones (Bruneton, J., 2001). TRADITIONAL USES The origin of the name hamamelis is much discussed. Some postulate that it comes from the Greek hama = at the same time and melis = fruit, referring to the plant's habit of producing flowers at the same time the previous year's fruits mature. The name Virginiana refers to the North American state where the plant was first identified. American natives used hamamelis as a medicine since much before the Conquerors arrived. They used bark and leaves decoction to treat inflammation, tumours and skin wounds. These folk uses were later adopted by the North American Eclectic School of medicine. In 1735, hamamelis was introduced into England. In 1882, it was included in the United States Pharmacopoeia. The forked branches of hamamelis have often been used by diviners as a stick to detect water or gold. In the popular medicine, hamamelis leaves are used internally, to relief diarrhoea, metrorrhagia, haemorrhoids, proctorrhagia, abundant vaginal discharge and digestive haemorrhage. Bark decoction is also recommended for these purposes, as well as for inflammation of the gums and mouth mucosa (as mouthwash or gargles). Bark decoction is also used in external applications to treat varix, muscle sprain, contusions and pain, to relief skin inflammation and as an eyewash. V 06-04/ ,43000,43010,43020,43040,43050,43080,

4 COSMETIC PROPERTIES Activity on blood circulation This activity is due to the flavonoids content of hamamelis extract. Several tests demonstrated that hamamelis flavonoids have phlebotonic, vasoprotective and capillarotropic effects, and that they reduce blood capillaries permeability. These effects are reinforced by the hamamelis leucoanthocyanidins. This activity was found very useful to treat haemorrhoids and varices. In two controlled clinical studies, the topical administration of a product containing 10% hamamelis (bark) to 165 haemorrhoids patients (grade 1) produced remarkable improvement of the symptoms in 79-90% of the cases, after three weeks of treatment. Topical as well as internal administration of hamamelis water (alone or along with other medicinal herbs), demonstrated anti-inflammatory activity on patients suffering haemorrhoidal pathology (Alonso J., 2004). Thus, hamamelis extract is useful to formulate cosmetic products aimed at the improvement of general blood circulation. Antimicrobial activity Hamamelis essential oil and tannins demonstrated bacteriostatic properties especially against Gram negative bacteria and antiviral action (mainly exerted by proanthocyanidins) against type 1 Herpes simplex, (Alonso J., 2004). Bacterial colonization plays an important role in the pathogenesis of atopic dermatitis and intertrigo. Gloor M et al. (2002) carried out a study to determine the antimicrobial activity of a topical dermatological preparation containing Hamamelis distillate (90%), urea (5%) and exipients. The preparation was applied to 15 healthy volunteers using the simple occlusion test. This formulation was found to be active against Staphilococcus aureus and Candida albicans. In odontology, the methanol extract of hamamelis leaves showed bactericidal effects against the bacteria producing periodontitis (Alonso J., 2004) Therefore, hamamelis extract is highly recommendable to formulate cosmetic products with antiseptic activity. V 06-04/ ,43000,43010,43020,43040,43050,43080,

5 Antioxidant activity Skin ageing is due to a number of causes, one of them being the UV radiation-induced reactive oxygen species. Scavenging these oxygen species is a way of preventing ageing. If the reactive oxygen species attack the cell membranes, membrane lipids undergo peroxidation, which induces mistakes in the numerous reactions that take place in the membranes. Thus, compounds with strong reactive oxygen scavenging properties are a good tool to fight ageing. Masaki H. et al. (1995) evaluated the scavenging activity of seven selected plant extracts (Aeseclus hippocastanum L., Hamamelis virginiana L. Polygonum cuspidatum Sieb., Quercus robur L., Rosemarinus officinalis L., Salvia officinalis L. and Sanguisorba officinalis L.) on active-oxygen species (superoxide anion, hydroxyl radical, singlet oxygen and lipid peroxide). The active-oxygen scavenging activities of these plants were evaluated on a murine dermal fibroblast culture system, and using both ESR spin-trapping and malondialdehyde generation methods. The results indicated that Aeseclus hippocastanum L. and Hamamelis virginiana L. had strong protective activity against cell damage induced by active oxygen. A number of tannins, especially hydrolysable tannins, inhibit adenosine diphosphate (ADP) and ascorbate-induced lipid peroxidation in rat liver mitochondria. The HHDP esters of glucose are major free radical scavengers and superoxide ion formation inhibitors. Some of them also inhibit the lipooxygenase enzyme in rat peritoneal granulocytes (Bruneton J., 2001). The antioxidant activity of flavonoids results from the combination of their iron chelating activity and their ability to scavenge the ageing-inducing free radicals (FR). Flavonoids can inhibit oxidases such as lipooxygenase (LO), cyclooxygenase (CO), mieloperoxidase (MPO), NADPH oxidase and xanthine oxidase (XO), thus preventing the in vivo formation of reactive oxygen species (ROS) and organic hydroperoxide. Additionally, it has been found that flavonoids inhibit enzymes indirectly involved in oxidative processes, such as the A2 phospholipase (PLA2) and stimulate other enzymes with well-known antioxidant properties, such as catalase (CAT) and superoxide dismutase (SOD). These are the mechanisms through which flavonoids interfere the propagation of free radicals and also their formation (Pérez Trueba, G., 2003). V 06-04/ ,43000,43010,43020,43040,43050,43080,

6 Such an antioxidant activity, allows for useful applications of hamamelis extract in products to treat wrinkles, aging and all of the oxidative processes affecting the skin and hair. Finally, we would like to mention that the book Plants preparations used as ingredients of cosmetic products. Vol. I (Council of Europe Publishing, 1994) includes two monographs on hamamelis leaves, one about the extract and one about the distillate. The cited publication also attributes cosmetic effects to hamamelis such as astringent, calming, anticouperosis, haemostatic, vein-vasoconstrictor and vasoprotective. The maximum recommended concentrations are 1-2% of the dry extract and 2-5% of the glycolic extract. Both extracts may be incorporated to formulations, such as tonics for the skin and mucosae, balm products and astringent products to treat minor hair problems (couperosis). COSMETIC APPLICATIONS Action Active Cosmetic Application Acts on blood circulation Anti-microbial Antioxidant Flavonoids Leucoanthocyanidins Tannins Essential oil Tannins Flavonoids Improves general blood circulation Antiseptic Anti-aging Photoprotection Hair color protection RECOMMENDED DOSE The recommended dose is between 0.5% and 5.0%. BIBLIOGRAPHY Alonso, Jorge. Tratado de Fitofármacos y Nutracéuticos. Barcelona: Corpus, 2004, p: (633.8 ALO). Bruneton J. Farmacognosia. Zaragoza: Ed. Acribia, 2001; p: (651*1 BRU). Council of Europe. Plants preparations used as ingredients of cosmetic products. Strasbourg Cedex: Council of Europe Publishing, 1994; p: (61*8 PAT). V 06-04/ ,43000,43010,43020,43040,43050,43080,

7 Deters A. et al. High molecular compounds (polysaccharides and proanthocyanidins) from Hamamelis virginiana bark: influence on human skin kerationcyte proliferation and differentiation and influence on irritated skin. Phytochemistry, 2001; p: Gloor M. et al. Antiseptic effect of a topical formulation that contains Hamamelis distillate and urea. Forsch Komplementarmed Klass Naturheilkd, 2002; 9 (3): Hamamelis Leaf. E.S.C.O.P. (ed). Monographs (On The medicinal Uses Of Plants Drugs).Exeter (UK), 1997; (633.8 (031) ENC). Huauf W. et al. Determination of hamamelitannin, catechins and gallic acid in witch hazel bark, twig and leaf by HPLC. J Pharm Biomed Anal., 2003; 33: Hughes-Formella BJ. et al. Anti-inflamatory effect of hamamelis lotion in a UVB erythema test. Dermatology., 1998; 196 (3): Masaki H. et al. Active-Oxygen Scavenging Activity of Plant Extracts. Biol.Pharm. Bull, 1995; 18 (1): (ref. 176). Pérez-Trueba G. Los flavonoides: antioxidantes o prooxidantes. Rev. Cubana Invest. Biomed., 2003; 22 (1): Ramos M.F.S. et al. Preliminary studies towards utilization of various plant extracts as antisolar agents. Int. J. Cosmet. Sci., 1996; 18: (ref. 2154) Websites: V 06-04/ ,43000,43010,43020,43040,43050,43080,