1. Diterpenoids: These are the main components of stevia, including stevioside and rebaudioside A.
2. Flavonoids: Such as rutin, quercetin, kaempferol, luteolin and their derivatives. These components are widely present in stevia and have important biological activities for plants.
3. Phenolic components: Including neochlorogenic acid, cryptochlorogenic acid, caffeoylquinic acid and isochlorogenic acid A~C, etc. These substances have good antioxidant activity because they contain multiple phenolic hydroxyl groups in their structure.
4. Polysaccharide components: Stevia leaves and rhizomes contain polysaccharide components, such as homogeneous polysaccharides containing a (1→6)-D-galactose main chain.
5. Volatile oils: Stevia leaves contain essential oils, most of which are semiterpenoid compounds, which together with flavonoids and quinine constitute the bitter components of stevia.
6. Other ingredients: including amino acids, alkaloids, vitamins, purines and some trace elements.
These ingredients together constitute the complex chemical composition of stevia extract, giving it a variety of pharmacological activities, such as hypoglycemic, anti-tumor, anti-oxidation, hypotensive, anti-inflammatory, and lipid-regulating effects.