Research Progress of the Biosynthesis and Regulation of Andrographolide

Andrographolide is the main active ingredient of Andrographis paniculata, which has the functions of clearing heat and detoxifying, antibacterial and anti-inflammatory, protecting liver and improving gallbladder. It is clinically used to treat pneumonia in children and upper respiratory tract infection. In recent years, because of the influence of environmental factors for a long time, not high purity and good varieties of selective breeding work lag and so on reasons, greatly restricted the quality improvement of andrographolide. In the quality evaluation of A. paniculata, the content of andrographolide is a very important index. Analyzing the molecular mechanism and accumulation rule of andrographolide biosynthesis is helpful to improve the quality of A. paniculata. In this review, the biosynthetic pathways and regulatory molecular mechanisms of andrographolide are comprehensively discussed. The biosynthesis of andrographolide is mainly divided into two stages, including the synthesis stage of andrographolide precursor and the modification stage of andrographolide synthesis. The synthesis of precursor has been relatively clear, but the mining of the pathways and key enzymes in the modification stage of andrographolide synthesis is still at a blank, and further research is needed. Through the excavation of the key factors affecting the synthesis and accumulation of andrographolide from the two levels of environmental factors and cropping systems, it is conducive to the establishment of a perfect and high-quality A. paniculata cultivation system. In addition, the research progress on the regulation of andrographolide biosynthesis was summarized and prospected, in order to provide research reference for the improvement of A. paniculata quality.