Kaffir lime is a citrus fruit native to tropical regions in Asia. 

The fruit is green, ripens to yellow and is distinguishable by its bumpy exterior and small size. 

The leaves are widely used in Southeast Asia cuisines, especially in Thai curries. 

It has a high content of alkaloids, citronellol, limonene, nerol and other organic compounds. 

As a traditional medicine, the fruits and leaves were used to treat headaches, fever, sore throat and indigestion. 

A study on kaffir lime demonstrated its antioxidant capacity with various experiments including

FRAP assay, DPPH assay and ORAC assay and determined its total phenolic content and flavonoid content. 

In another study, a methanol extract of kaffir lime showed antioxidant activities 

by scavenging free radicals as well as prooxidant effect b preventing DNA damage.