Heat oil in sauce pan or large skillet. Add rice. Saute until golden. Add onion, green pepper, salt, cayenne, garlic clove, tomatoes, tomato juice, water and undrained mushrooms. Cook covered over low heat 35-40 minutes for brown rice, 20 minutes for white or Basmati rice, stirring occasionally. Add tuna and heat through right before serving. Remove garlic right before serving.