Vembala pattai or Alkanet Roots are the roots of a small plant growing in Himalayas and in several Europian countries. Those roots are dried well, cleaned, and made available online as raw material. It is being used by our people along with Coconut oil for its colouring ability because of its natural colouring substance called as Alkanine. 

Disclaimer: Before taking any herbal as an intake, you are requested to consult with a Siddha or Ayurveda Doctor or any other Traditional Siddha Physician to avoid further health related problems. They will help you to understand the procedure, the effect of Herbals and foods to avoid if any, upon consuming the herbs.