Chemical composition, antioxidant and multi-enzymatic inhibitory potential of licorice harvested from wild populations in Iraq

The current work focuses on comparing the chemical composition, the antioxidant activities and the enzyme inhibitory properties of licorice collected from ecologically distinct regions of Iraq, namely: Wasit and Al-Diwaniyah. The chemical compositions of the aerial parts volatile oils, extracted via hydrodistillation, were characterized by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC–MS) techniques. Furthermore, the evaluation of enzyme inhibitory properties of both samples against acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, and α-glucosidase were performed. Subsequently, the antioxidant properties were assessed using DPPH and ABTS radical scavenging methods, cupric and Ferric reducing power (CUPRAC and FRAP), metal chelating ability (MCA) and phosphomolybdenum (PBD) assay. Thus, the chemical analysis showed the richness of Glycyrrhiza glabra Linn. volatile oils in oxygenated aliphatic hydrocarbons, with Palmitic acid identified as the major constituent (41.1%-51.6%). Conclusively and as a result of antioxidant assays, licorice from Al-Diwaniyah region was more active than same specie located in Wasit. Both volatile oils exhibited significant cupric ion reducing antioxidant capacity with values ranging between (36.66 and 41.68 mg TE/g). Moreover, G. glabra presented a significant anti-tyrosinase activity, with inhibition values of 58.33 and 52.53 mg KAE/g for Wasit and AL-Diwaniyah populations respectively.