Trends in Rooibos Tea (Aspalathus linearis) research (1994–2018): A scientometric assessment

Abstract

This bibliometric assessment aimed to gain insight into the publication landscape over a 25-year period on one of South Africa's most coveted indigenous plants, Aspalathus linearis, known in commerce as rooibos tea. Despite the growing global market, and acceptance as a refreshing and health-promoting tea, scientific publications on rooibos, have not been subjected to scientometric analyses. A total of 421 relevant documents spanning the period 1994-2018 as indexed in the Scopus database were considered using VOSviewer. The global publication contribution on rooibos tea shows an average annual growth rate of 27.2%, and citation impact averaged 30 per publication. South African authors dominated the research landscape, contributing to approximately 60% of the total publication output. Prominent research themes include oxidative stress and inflammatory process mitigation using rooibos tea extracts, agronomy and fair trade in the rooibos tea industry, metabolic syndrome research, antioxidant activity, toxicity, quality control of rooibos tea and formulated products. More recently, a research focus has developed around bioavailability evaluation of rooibos tea components, green synthesis and nanoparticle formulations with the aim of improving the efficacy and potency of rooibos tea in the treatment of Type 2 Diabetes. We propose that research attention should be devoted to the mechanistic action of rooibos metabolites in mitigation of infectious diseases, diabetes, cardiovascular diseases and obesity which will inevitably lay the foundation for clinical studies to proceed.