Consumer acceptability of liquorice root (Glycyrrhiza glabra L.) as an alternative sweetener and correlation with its bioactive content and biological activity

Abstract

Consumer acceptability and sensory properties of liquorice root (Glycyrrhiza glabra L.) were evaluated. Quantitation of total polyphenolics and glycyrrhizic acid (GA), as well as the antioxidant capacity of liquorice extracts, was conducted and their biological effects (cytotoxic, antioxidative/pro-oxidative activity, lipid peroxidation on human laryngeal carcinoma cell line) compared to the ones of their predominant bioactive compound – GA. Conducted consumer survey revealed poor familiarity with liquorice (12.37% of correspondents), but willingness towards its use as an alternative sweetener (77.32% of consumers). Polyphenolic content of evaluated extracts ranged from 1018.18 to 1277.27 mg gallic acid equivalents (GAE)/l while GA content varied between 2179.53 and 2944.13 mg/l. The most pronounced cytotoxic effect (60%) and lipid peroxidation were exerted by treatment with the highest applied extract concentrations (10 mg/ml). Pure GA exhibited cytotoxic and pro-oxidative effects at concentrations of 0.12–0.6 mg/ml. Due to high GA content, coupled with its pronounced cytotoxic activity, the intake of liquorice root should be limited.

Keywords:

• Antioxidative/pro-oxidative activity
• cytotoxicity
• lipid peroxidation
• liquorice
• sensory properties

Acknowledgements

All institutional and national guidelines for the use of model cell lines were followed.

Declaration of interest

This work was supported by the Ministry of Science, Education and Sports, Republic of Croatia projects Nr. 058-0000000-3470 and 058-0582261-2246. The authors declare that they have no conflicts of interest.