Liquorice leaves and flavonoids: the latest research findings

Liquorice (Glycyrrhiza glabra L.) is a perennial plant belonging to the Fabaceae (Legume) family, known since antiquity as “black gold“.

In Chinese medicine, it was considered a precious commodity and was also used in ancient Egypt, Greece, and Rome as a remedy for many ailments.

Currently, liquorice is cultivated in many parts of the world with a temperate climate, and its root is used to produce a dark, thick juice that is then employed, thanks to its sweet and pleasant taste, in candy production and as a flavoring.

Liquorice, pinocembrin, and scientific research

For many years, scientific research has focused its studies on the root, discovering countless virtues of liquorice: it is anti-inflammatory, antibacterial, antioxidant, prevents stomach ulcers, soothes coughs, and alleviates sore throats. It prevents the development of liver cancer in those with chronic hepatitis C, is one of the essential components in the PC-SPES blend (dietary support for maintaining prostate health and function), stimulates hair regrowth in those with alopecia, and lightens skin spots formed due to excess melanin.

All these properties are due to the presence of numerous classes of chemical compounds, including Flavonoids, which are the most numerous components of liquorice and have antioxidant power 100 times stronger than vitamin E!

Recent studies have shown, however, that the part of the liquorice plant containing the highest amount of Flavonoids is not the root but the leaves.

The aerial parts of liquorice, as they were not the plant’s main resource, were long used as fodder for cattle, flocks, and as fertilizer. Science reveals to us today that the leaves are rich in substances that are not contained in the root or are present in reduced quantities.

The major component present in the leaf extract is a Flavonoid called Pinocembrin, also found in other plants, honey, and propolis, which possesses various properties: it is antioxidant, anti-inflammatory, antimicrobial, and antitumor.

Some studies have shown that Pinocembrin is capable of inducing the death of blood and colon tumor cells; it also eliminates nitrites present in the digestive tract, introduced through diet and considered among the likely culprits for the formation of colon and stomach tumors. It is also neuroprotective, as it prevents possible injuries due to cerebral ischemia.

Liquorice leaf extract has shown beneficial effects even on the skin as it can boast anti-wrinkle, moisturizing, and protective properties.

The exact mechanisms by which Pinocembrin acts have not yet been fully clarified, but discovering that leaves also possess significant properties greatly increases the economic value of the liquorice plant because it can be exploited in its entirety and used in the cosmetic, pharmaceutical, and food industries.

FEDERICA AIELLO