I have Office 365 Developer account & tenant in windows azure to manage office 365 users. using consent framework \"prompt=admin_consent\", i granted access rights to one of
If you have an organisation account with Microsoft you should be able to access this page: https://portal.office.com/account
From there click either App permissions
on the left, or Change app permission
in the middle.
This will take you to a screen that looks like this:
Where you can revoke which app permissions you don't want anymore.