Dear Dinesh

It is suggested that doses of 200–400 mg for adult humans can cause toxic symptoms (20–40 mg for children). Most commercial potatoes have a solanine content of less than 0.2 mg/g.However, potatoes that have been exposed to light and have started to turn green can show higher concentrations.

A more homely source of solanine is the common potato (solanum tuberosum), whose average content is 8 mg. per 100 g. The interior of the potato contains less than this, and too little to cause any toxic effects. The toxic dose is 20 to 25 mg .

following the answers

Solanine contents above the recommended level is 20 mg/100 g (fresh weight) of potato).