Planta Med 2018; 84(09/10): 568-583
DOI: 10.1055/s-0044-100622
Georg Thieme Verlag KG Stuttgart · New York

Aspalathin from Rooibos (Aspalathus linearis): A Bioactive C-glucosyl Dihydrochalcone with Potential to Target the Metabolic Syndrome

Rabia Johnson
1   Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa
2   Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
Dalene de Beer
3   Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch, South Africa
4   Department of Food Science, Stellenbosch University, Stellenbosch, South Africa
Phiwayinkosi V. Dludla
1   Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa
2   Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
Daneel Ferreira
5   Department of BioMolecular Sciences, Division of Pharmacognosy and the Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, Mississippi, United States
Christo J. F. Muller
1   Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa
2   Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa
6   Department of Biochemistry and Microbiology, University of Zululand, Kwadlangezwa, South Africa
Elizabeth Joubert
3   Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch, South Africa
4   Department of Food Science, Stellenbosch University, Stellenbosch, South Africa
› Author Affiliations
Further Information

Publication History

received 10 November 2017
revised 19 December 2017

accepted 28 December 2017

Publication Date:
31 January 2018 (online)


Aspalathin is a C-glucosyl dihydrochalcone that is abundantly present in Aspalathus linearis. This endemic South African plant, belonging to the Cape Floristic region, is normally used for production of rooibos, a herbal tea. Aspalathin was valued initially only as precursor in the formation of the characteristic red-brown colour of “fermented” rooibos, but the hype about the potential role of natural antioxidants to alleviate oxidative stress, shifted interest in aspalathin to its antioxidant properties and subsequently, its potential role to improve metabolic syndrome, a disease condition interrelated with oxidative stress. The potential use of aspalathin or aspalathin-rich rooibos extracts as a condition-specific nutraceutical is hampered by the limited supply of green rooibos (i.e., “unfermented” plant material) and low levels in “fermented” rooibos, providing incentive for its synthesis. In vitro and in vivo studies relating to the metabolic activity of aspalathin are discussed and cellular mechanisms by which aspalathin improves glucose and lipid metabolism are proposed. Other aspects covered in this review, which are relevant in view of the potential use of aspalathin as an adjunctive therapy, include its poor stability and bioavailability, as well as potential adverse herb-drug interactions, in particular interference with the metabolism of certain commonly prescribed chronic medications for hyperglycaemia and dyslipidaemia.

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