**EXHIBIT 10.73**

**PROMISSORY NOTE**
| $1,100,000.00 | March 31, 2006 |
|---------------|----------------|

FOR VALUE RECEIVED, theundersigned, Earth Biofuels, Inc., a Delaware corporation (“*Maker*”), hereby promises to pay tothe order of Southern Biofuels, LLC, a Mississippi limited liability company (“*Payee*”), the principal sum of OneMillion One Hundred Thousand and No/100 Dollars ($1,100,000.00), together withinterest thereon as provided for below.

Theprincipal of this Promissory Note (this “*Note*”)shall be due and payable June 29, 2006.

Theunpaid principal balance of this Note shall bear interest from the date hereofuntil paid in full at the rate of 7.25% per annum.

Principaland all accrued interest are payable at P.O. Box 54461, Jackson, Mississippi39288, or at such other address as the Payee of this Note may from time to timedesignate in writing.

Inthe event that Maker fails to pay any principal of or interest on this Notewhen due:

(1)           Maker shall convey to Payee apercentage ownership interest (the “*Interest*”)in the Plant (as defined below) that is equal to the product of (a) twenty-fivepercent (25%) multiplied (b) a fraction, the numerator of which is the amountthat Maker has failed to pay when due, and the denominator of which is$1,100,000.

(2)           Notwithstanding its minorityownership interest in the Plant, Payee shall have exclusive control of thePlant and its operations.  Payee alsoshall be given full access to the Plant and the Plant site, free of any rentobligations.  Payee further shall begiven possession of all permits and approvals for the operation of thePlant.  Maker shall use its continuingand best efforts to make the Plant, or cause the Plant to be made, Operational(as defined below), if it is not then already Operational.

(3)           Once Maker has made the necessarypayments of principal and/or interest, Payee shall convey the Interest back toMaker, and the rights and obligations of Maker and Payee under paragraph (2)shall cease.

Forpurposes of this Note, (w) “*Plant*”means that certain biodiesel refinery owned by Maker and located in Durant, Oklahoma,which was previously owned by Payee; (x) “*Operational*”means that the Plant is processing biodiesel from materials in operationalconditions agreed upon by Maker and Payee to the specifications of ASTM D6751at the Required Rate; (y) “*Required Rate*”means processing 6,300 to 7,700 gallons of biodiesel per day as per conditionsstated in the Letter of Intent; and (z) “*Letter of Intent*”means that certain letter agreement, dated as of February 13, 2006, betweenMaker and Payee.

ThePayee shall not, by any act (except by a written instrument executed anddelivered in accordance with this paragraph), delay, indulgence, omission orotherwise be deemed to have waived any right, remedy or other power hereunder orto have acquiesced in any default hereunder. No waiver, amendment, supplement or other modification of any of the termsor provisions of this Note

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shall be effectiveunless set forth in a writing executed and delivered by the party sought to becharged.

Makerwaives presentment, diligence, protest, demand, notice of demand, notice ofacceptance or reliance, notice of non-payment, notice of dishonor, notice ofprotest and all other notices to parties in connection with the delivery,acceptance, performance, default or enforcement of this Note, any endorsementor guaranty of this Note, or any collateral.

The undersignedagrees to pay upon demand all of Payee’s costs and expenses, including Payee’sattorneys’ fees and Payee’s legal expenses, incurred in connection with thecollection of this Note. If there is a lawsuit, Guarantor agrees upon Payee’srequest to submit to the jurisdiction of the courts of Rankin County, State ofMississippi.

THISNOTE SHALL BE GOVERNED BY AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH THELAWS OF THE STATE OF MISSISSIPPI, WITHOUT REGARD TO THE CONFLICTS OF LAWSPRINCIPLES THEREOF.

INWITNESS WHEREOF, Maker has executed and delivered this Note as of the date setforth above.
|   | EARTH BIOFUELS, INC. |
|--------|----------------------|
|   |                 |
|   |                 |
|   | By:                  | /s/ DENNIS MCLAUGHLIN |   |
|   | Name:                | Dennis McLaughlin |
|   | Title:               | CEO |

 

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