Comprehensive review of two groups of flavonoids in Carthamus tinctorius L.

Safflower (Carthamus tinctorius L.) is cultivated in various countries for the flavonoid compounds it contains. These flavonoids have been used in many industries as drugs and/or dyes. Over 60 flavonoids have been isolated from safflower. These flavonoids can be divided into two groups: special and common, both of which are active pharmaceutical ingredients efficacious in the treatment of cardiovascular and cerebrovascular diseases. Gene functions have been studied to figure out the biosynthesis of flavonoids in safflower. However, there is no comprehensive summary of the flavonoids in safflower. Research was recognised through systematic searches of ScienceDirect, PubMed, Web of Science, and CNKI databases by searching terms of "Carthamus tinctorius L.", "safflower", "flavonoid", "pharmacology", and "gene". More than 200 research reports were included after eligibility checks. This study summarizes the application of flavonoids in medicine and other industries. Comprehensively collects the chemical structure information of the two groups of flavonoids, and organic acids, alkaloids, spermidine, polyacetylene, and polysaccharides. The mechanism of two groups of flavonoids in treatment of cardiovascular and cerebrovascular diseases was describe in detail, and pharmacological mechanisms of protecting liver, lung and bone, and anti-cancer and anti-inflammatory were also summarised. Besides, the study updated the latest information on the molecular biology of safflower flavonoids. It is found that two groups of flavonoids in safflower have obvious differences in application, chemical structure, pharmacological mechanism, and biosynthetic pathway. It is hoped that this summative research will provide a new insight to flavonoids research in safflower.