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

Rabia Johnson; Dalene de Beer; Phiwayinkosi V. Dludla; Daneel Ferreira; Christo J. F. Muller; Elizabeth Joubert

doi:10.1055/s-0044-100622

Planta Medica, Table of Contents

Planta Med 2018; 84(09/10): 568-583
DOI: 10.1055/s-0044-100622

Reviews

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

¹Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa

²Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa

,

Dalene de Beer

³Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch, South Africa

⁴Department of Food Science, Stellenbosch University, Stellenbosch, South Africa

,

Phiwayinkosi V. Dludla

¹Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa

²Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa

,

Daneel Ferreira

⁵Department 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

¹Biomedical Research and Innovation Platform (BRIP), Medical Research Council (MRC), Tygerberg, South Africa

²Division of Medical Physiology, Faculty of Health Sciences, Stellenbosch University, Tygerberg, South Africa

⁶Department of Biochemistry and Microbiology, University of Zululand, Kwadlangezwa, South Africa

,

Elizabeth Joubert

³Plant Bioactives Group, Post-Harvest and Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch, South Africa

⁴Department of Food Science, Stellenbosch University, Stellenbosch, South Africa

› Author Affiliations

Abstract

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.

Key words

Aspalathus linearis - Fabaceae - aspalathin - metabolic syndrome - oxidative stress - molecular mechanism - bioavailability - herb-drug interactions

Full Text

References

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