Blueberries ( Vaccinium myrtillus L.) from a miraculous family of Ericaceae are very well known from practical consumption and I know they belong to the most valuable fruits (super-eaters), especially when they are harvested in their own right. I mention them as an example that the most valuable adaptogens may not be exotic.
Blueberries contain a huge amount of polyphenol antioxidants, coffee acid, ferulic acid, not to mention the usual fruit, vitamins and minerals. Blueberries slow down aging, treat diseases of the digestive tract, protect against diabetes, atherosclerosis and civilization diseases - I know so much without reading scientific reports such as Smeriglio2014hev .