Anti diabetic principle cheratin is present in

Anti-diabetic principle cheratin is present in bitter gourd.
Bitter gourd is traditionally known for its medicinal properties such as antidiabetic, anticancer, anti-inflammation, antivirus and cholesterol-lowering effects. It contains many phenolic compounds that may have the potential as antioxidants and antimutagen.
It has several chemicals that seem to act like insulin and help to lower blood sugar levels.