A comprehensive review of azadirachtin: physicochemical properties, bioactivities, production, and biosynthesis

Azadirachtin, a complex tetratriterpenoid limonin with potent insecticidal properties, is the most widely used biological pesticide worldwide. Its versatile pharmacological applications include the inhibition of tumor growth and anti-malarial, anti-bacterial, and anti-inflammatory properties. Azadirachtin plays a pivotal role in pest control and novel drug development. The primary source of azadirachtin is the neem tree ( Azadirachta indica A. Juss), with an azadirachtin content ranging from 0.3% to 0.5%. Despite the market demand for botanical pesticides reaching approximately 100,000 tons per year, the annual neem production in China is only 1.14 tons. Although azadirachtin can be obtained through plant extraction or chemical synthesis, the quantity obtained does not meet the market demand in China. The sluggish pace of azadirachtin biosynthesis results from the limited availability of genetic information and the complexity of the synthetic pathway. Recent advancements in azadirachtin biosynthesis hold promise as an efficient collection method. In this study, we explored the physicochemical properties, biological activities, mechanisms of action, and acquisition methods of azadirachtin. We also delved into recent progress in azadirachtin biosynthesis and assessed potential future usage challenges. This study aims to establish a theoretical foundation for the scientific application and efficient synthesis of azadirachtin, offering valuable reference information to the industry.