In the last ten years, the use of antibiotics as additives in livestock feed has been limited all over the world. The restriction is due to the concerns over the spread of resistant pathogenic bacteria and over antibiotic residues in animal final products. This raised the interest for alternative phytogenic additives to improve livestock health and production. A potential option is the use of the liquorice extract (Glycyrrhiza glabra) as feed additive, which has been studied mainly in monogastric animals and – in the last few years – in ruminants too (Xuefeng Guo et al., 2019).
The liquorice (Glycyrrhiza glabra) is an herbaceous plant of Fabaceae, originating from south-west Asia and Mediterranean regions, and used for millennia in folk medicine of many cultures, thanks to its high content of triterpenoids and flavonoids. With the development of the modern pharmacology, numerous precious and important pharmacological activities have been discovered concerning liquorice, full of beneficial properties. In particular, it carries out an anti-inflammatory activity due to two triterpenoids (glycyrrhetinic acid and glycyrrhizin) and numerous flavonoids isolated from the root (such as the glabridin), which carry out their activities through the inhibition of COX, PGE2, cytokines and their receptors, and the nuclear transcription factor, as well as through the removal of oxygen free radicals (Rui Yang et al., 2015).
Another important action ascribed to liquorice is the immunoregulation. Among the liquorice compounds, the glycyrrhizin polysaccharides are believed to play an essential role in stimulating the organism’s immune ability, since they affect the body’s specific and non-specific immune functions and activate the immune cells. Therefore, to sum up, the compounds isolated from liquorice carry out an immunoregulatory activity, modulating the production of cytokines and interleukin, the expression of molecules on the cell surface, and the immune responses (Rui Yang et al., 2015).
Besides having antimicrobial properties, the liquorice – in the last few years – has showed hepatoprotective properties. In particular, the glycyrrhetinic acid, the glycyrrhizin and the dehydrogliasperin C have demonstrated to be efficient in almost all the course of yeast diseases. The oxidative stress, the lipid peroxidation and the reaction of transaminases are some of the mechanisms that can lead to the hepatic dysfunction. The liquorice exerts its hepatoprotective effect by regulating the CYP enzymes expression, attenuating the oxidative stress, improving the cell structure stability and the biological membrane systems, and inhibiting the cytolytic activity of the complement systems and apoptosis (Rui Yang et al., 2015).
The particularity of using the liquorice in Akron’s products lies in its specific method of preparation. In facts, the extract of liquorice root undergoes the fermentation process that promotes the functional activities such as the antioxidant and anti-inflammatory activities and increases vitamins, enzymes and growth factors contained in the fermented products. Moreover, several scientists have also reported the medicinal herbs beneficial effects on the animals’ growth performances and immune system. The microbial fermentation has thus been identified as a fruitful process to improve the liquorice health-giving properties, supporting the anti-inflammatory and antioxidant activities, which affect the animal’s gastrointestinal tract.
1. “Effects of Licorice Extract Supplementation on Feed Intake, Digestion, Rumen Function, Blood Indices and Live Weight Gain of Karakul Sheep” Xuefeng Guo,Long Cheng,Junfeng Liu, Sujiang Zhang,Xuezhao Sun and Omar Al-Marashdeh, 2019
2. “Effects of dietary natural and fermented herb combination on growth performance, carcass traits and meat quality in grower-finisher pigs” Sonia Tabasum Ahmed, Hong-Seok Mun, Md. Manirul Islam, Seok-Young Ko, Chul-Ju Yang 2016
3. “The Pharmacological Activities of Licorice” Rui Yang, Li-qiang Wang, Bo-chuan Yuan, Ying Liu 2015