RCM Engineering, Inc. March 21, 2011 Regent Technologies, Inc. 5646 Milton, Suite 722 Dallas, TX 75206 Gentlemen: As an independent petroleum consultant, I hereby consent to the inclusion of our report setting forth the estimates of the oil and gas reserve's and revenues from the oil and gas reserves of Regent Natural Resources Co. as of December 31, 2010 in the form and context in which it appears, in the Annual Report on Form 10-K and to all references to our firm included in the Annual Report with, with respect to the referenced report. Very truly yours, Richard McPherson P.E. #47084 (214) 969-9111 5646 Milton, Suite 716 Dallas, Texas 75206