The liquorice plant, Glycyrrhiza glabra, belongs to the extensive family of Fabaceae. It is a relative of the wisteria, clovers, and peas. From its root, a compound also known as liquorice is extracted, which contains several molecules beneficial to the skin, thanks to their antioxidant and anti-inflammatory actions.
What you need to know about liquorice extract.
Summary
Published on October 4, 2024, by Maylis, Chemical Engineer — 6 min of reading
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Licorice extract, a bit of history.
The smooth liquorice, botanically known as Glycyrrhiza glabra is primarily renowned for its aromatic roots. It originates from southern Europe and Asia, and now grows in various regions around the world (Mediterranean basin, southern United States, the Middle East, North Africa, Mauritius). In traditional medicine, liquorice was a plant recognised for its abilities to treat colds, soothe heart pains, aid digestion, and calm bouts of coughing. It is consumed in the form of herbal tea but also as a stick, which corresponds to the underground stem of the plant.
Today, liquorice extract is a compound frequently found in cosmetic formulas. It is hidden behind the following I.N.C.I. names: ammonium glycyrrhizate, dipotassium glycyrrhizate, glycyrrhetinic acid or glycyrrhiza glabra root extract. Its recommended dosage is between 2 and 5%.
To obtain this extract, the roots are dried, peeled, and then ground into a powder. The resulting compound predominantly contains glabridine (over 95%). It also contains glycyrrhizic acid, known for its anti-inflammatory properties, as well as flavonoids and isoflavonoids (glabrene, isoliquiritigenin), capable of inhibiting tyrosinase involved in the synthesis of melanin.
Note : At Typology, we use "Glycyrrhiza Glabra Root Extract". Over 95% rich in glabridin, it inhibits melanin, hence its anti-spot properties. However, from liquorice, it is also possible to extract glycyrrhetinic acid (INCI name: Glycyrrhetinic Acid). This compound has contradictory properties compared to the "Glycyrrhiza Glabra Root Extract". Indeed, it is classified as pro-melanin, meaning it stimulates melanogenesis, which is responsible for tanning. It is therefore often found in self-tanning products.
Licorice extract to combat pigmentation spots.
Pigment spots or hyperpigmentation are caused by a disruption in the pigmentation process. The melanin is overproduced in certain areas, leading to the appearance of spots that affect the uniformity of the complexion. These spots can be categorised into three types: the melasma or pregnancy mask , related to hormonal imbalances, the lentigo or sun spots, due to excessive and repeated sun exposure, and the post-inflammatory hyperpigmentation which results from an overproduction of melanin following inflammation (wounds, burns, blemishes, acne outbreaks).
Licorice extract is often compared to hydroquinone due to its pigment regulating nature. It has the advantage of being gentler and better tolerated by the skin than hydroquinone, which has been banned in all cosmetic products by European regulations since 2001. The effectiveness of licorice extract is due to the presence of glabridin, a powerful depigmenting agent known for its brightening and anti-spot virtues. It is capable of inhibiting tyrosinase, which is responsible for the production of melanin. The equation is simple: less melanin means less pigment, fewer brown spots, and a more even complexion.
Licorice extract to limit skin ageing due to oxidative stress.
Rich in glabridin, a polyphenolic flavonoid with antioxidant properties, liquorice extract is an excellent ally in protecting the skin from free radicals. As a reminder, these arereactive oxygen species naturally produced by the body. However, when cells are faced with astress, they generate them excessively. The sources of stress are numerous, the main ones being exposure to UVA, pollution, smoking, a diet too rich in fats and/or sugars. Free radicals are particularly unstable molecules due to theirsingle electron. They tend to react with other molecules to form apair of electrons, and thus causedamage to cells, DNA and proteins in the body. This accelerates ageing and wrinkles appear on the skin surface. The flavonoids present in liquorice extract specifically neutralise thesuperoxide anion, denoted O₂.⁻, thus preventing it from harming the skin's healthy molecules. Therefore, this plant-based active ingredient delays skin ageing and protects the skin from external aggressions.
Licorice extract to soothe irritations.
Glycyrrhizic acid gives this extract anti-inflammatory properties. It thus soothes irritated skin, redness, and itching. It is particularly effective on atopic skin. It is referred to as natural cortisone: it effectively alleviates eczema.
In which skincare products can one find liquorice extract?
Due to its soothing properties, liquorice extract is recommended for skin prone to itching, with an atopic tendency, subjected to aggression (cold, UV, pollution...) and sensitivity. To limit the appearance of skin spots due to ageing, mature skin can also use treatments containing liquorice extract. This compound is thus present in brightening serums and soothing creams.
Ouranti-mark serumthus contains liquorice extract combined with other brightening and repairing active ingredients, such as gluconolactone from the P.H.A. category and extract ofCentella asiatica. To fade acne scars, apply a drop locally to the affected areas, in theevening only.
Sources:
SARKAR R. & al. Cosmeceuticals for hyperpigmentation: What is available?Journal of Cutaneous and Aesthetic Surgery (2013).
FRATTARUOLO L. & al. Antioxidant and anti-inflammatory activities of flavanones from Glycyrrhiza glabra L. (licorice) leaf phytocomplexes: identification of licoflavanone as a modulator of NF-kB/MAPK pathway. Antioxidants (Basel) (2019).
