Hedyotis-Oldenlandia genus: A review of traditional Chinese medicine herb

Members of Rubiaceae family are a rich source of secondary metabolites existing as pure compounds or standardized crude extracts. It has provided a wide range of opportunities for the exploration and discovery of new drugs. Hedyotis or Oldenlandia is one of the important members of this family and has shown multifunctional pharmacological properties according to continuous scientific research conducted on that plant genus since last few decades. The justification of use of Hedyotis-Oldenlandia in folk medicine is supported by its reported biological activities including anticancer, antioxidant, antidiabetic, anti-inflammatory and antimicrobial activities. This genus also has been recognized to be abundant with bioactive phenolic compounds, proteins, carbohydrates, steroids and terpenoids. Therefore, this review highlights the traditional uses, phytochemical profiling and phenolic contents, pharmacological review and structure-activity relationship of chemical constituents in Hedyotis-Oldenlandia plants. However, further studies are still required to explore the molecular targets responsible for the reported pharmacological properties in order to establish a comprehensive profile of the isolated compounds before proceeding with further clinical trials