Crude oil futures edged up on light bargain hunting on Tuesday, after U.S. and Brent crude tumbled in the previous session to post their biggest daily percentage declines since the start of September. Oil prices sank on Monday after a report that OPEC continued to boost production. Global benchmark Brent crude had gained 40 cents to $50.26 a barrel by 0243 GMT, after dropping $2.79 in the previous session to $49.86.