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                                                                    EXHIBIT 10.1

                              AGREEMENT AND RELEASE

         WHEREAS, DEMETER BIOTECHNOLOGIES, LTD and/or DEMEGEN, INC. (hereinafter
"Demegen") and MYCOGEN CORPORATION and/or DOW AGROSCIENCES LLC (hereinafter
"Mycogen") were parties to a certain Restated Demeter-Mycogen License and
Royalty Agreement, effective September 23, 1997 (the "1997 Agreement") and to a
certain Addendum to the Restated Demegen-Mycogen License and Royalty Agreement,
effective October 10, 1998 (the "1998 Addendum");

         WHEREAS, Demegen has asserted claims and allegations against Mycogen in
a certain arbitration proceeding (the "Arbitration") pending before Technology
Mediation Services, LLC, Sandra A. Sellers presiding (the "Arbitrator");

         WHEREAS, Demegen has alleged Mycogen breached the 1997 Agreement and
the 1998 Addendum;

         WHEREAS, Mycogen disputes the claims and allegations made against it by
Demegen;

         WHEREAS, Mycogen has asserted that it was entitled to a return from
Demegen of certain payments made to Demegen;

         WHEREAS, Demegen disputes the claims and allegations made against it by
Mycogen; and

         WHEREAS, to avoid the uncertainties inherent in the Arbitration, and in
order to purchase peace between themselves, and neither party admitting fault or
liability or the merits of their respective positions, each as against the
other, Demegen and Mycogen agree to settle and resolve the disputes between
them, fully and forevermore, according to the terms and conditions as set forth
below.

         NOW, Therefore, in exchange for and in consideration of the mutual
promises herein set forth, and intending to be bound thereby, Demegen and
Mycogen agree as follows:

         1. On or before June 17, 2002, Mycogen will pay Demegen six hundred
fifty thousand dollars ($650,000) as final research payments and partial
reimbursement of legal expenses.

         2. On or before June 17, 2002, Mycogen will pay DeForest & Koscelnik a
separate sum in the amount of one hundred fifty thousand dollars ($150,000).

         3. On or before June 17, 2002, Mycogen will pay Demegen the amount of
thirteen thousand dollars ($13,000) as reimbursement of the Arbitrator's
retainer previously paid by Demegen. Should any portion of the thirteen thousand
dollars ($13,000) paid by Demegen to the Arbitrator be reimbursed, said funds
will belong to Mycogen. Mycogen will pay any additional charges by the
Arbitrator, related to the Arbitration.


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         4. On or before June 17, 2002, Mycogen will pay Demegen a separate sum
in the amount of forty-three thousand four hundred forty-two dollars ($43,442)
attributable to patent expenses which are the obligation of Mycogen under the
1997 Agreement.

         5. Demegen agrees that Mycogen has made or committed herein to make all
payments required under the 1997 Agreement and/or the 1998 Addendum. Mycogen
agrees that Demegen shall not be required to return to Mycogen any prior
payments made by Mycogen.

         6. The parties stipulate and agree that the 1997 Agreement was properly
terminated under Article XIX thereof on April 30, 2002, and that the 1998
Addendum was properly terminated under Article XIII thereof on March 15, 2002,
and that all further and future rights, responsibilities and obligations between
them thereunder are as provided in the 1997 Agreement and the 1998 Addendum.

         7. Mycogen represents and warrants that no licenses, sublicenses, or
assignments of rights have been made under the 1997 Agreement or the 1998
Addendum.

         8. Demegen and Mycogen agree that CRADA #58-3K95-M-669 which expires
July 20, 2002, should be completed by Mycogen.

         9. Demegen represents and warrants that it has not disclosed to Mycogen
any confidential information or trade secrets to which it asserts any
proprietary and/or pecuniary interest, or for which it is entitled to
compensation or further consideration of any kind or type other than the
payments as set forth herein, except as stated on the attached Exhibit "1" and
to the extent the information associated with the patent applications referenced
in said Exhibit "1" is not published by issuance of patents relating thereto,
and the amino acid sequences on Attachment A to Exhibit "1" have not been or do
not become published or communicated to Mycogen by a third party having the
legal right to do so.

         10. Demegen, for itself and its past or present parent corporations,
subsidiaries, successors and assigns, does hereby irrevocably and
unconditionally release, remise, settle, compromise and forever discharge
Mycogen and any of its past or present parent corporations, subsidiaries,
representatives, agents, attorneys, officers and employees, and their heirs,
successors and assigns, from any and all liability, actions, causes of action,
judgments, claims, damages and demands of whatsoever kind and nature (including
but not limited to attorneys fees, expenses and costs) which they have or may
have or claim to be entitled to, arising from any actual or alleged actions or
failures to act, known or unknown, up to and including the date of execution
hereof, which are or might be alleged to be a breach of the 1997 Agreement
and/or the 1998 Addendum.

         11. Mycogen, for itself and its past or present parent corporations,
subsidiaries, successors and assigns, does hereby irrevocably and
unconditionally release, remise, settle, compromise and forever discharge
Demegen and any of its past or present parent corporations, subsidiaries,
representatives, agents, attorneys, officers and employees, and their heirs,
successors and assigns, from any and all liability, actions, causes of action,
judgments, claims, damages and demands of whatsoever kind and nature (including
but not limited to attorneys fees, expenses and costs) which they have or may
have or claim to be entitled to, known or unknown, arising from any actual or
alleged actions or failures to act, up to and including the date of execution
hereof, which are or might be alleged to be a breach of the 1997 Agreement
and/or the 1998 Addendum.

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         12. Demegen's claims in the Arbitration before the Arbitrator are
hereby withdrawn and terminated with prejudice. Demegen will execute any and all
additional documents reasonably necessary, if any, to effectuate the termination
of the Arbitration.

         13. Neither party will disclose the substantive terms of this Agreement
and Release other than (a) to counsel, accountants, potential investors,
acquirers, business partners or further as necessary to assert their legal
rights or discharge their legal obligations (including, but not limited to,
disclosure to comply with the securities laws or disclosure to Louisiana State
University), (b) in a statement mutually agreed between the parties, provided
that agreement thereto shall not be unreasonably withheld, or (c) Demegen may
advise that amounts in its financial statements are attributable to an amicable
resolution of issues relating to the 1997 Agreement and the 1998 Addendum.

         14. There are no understandings between the parties regarding this
Agreement and Release other than as specifically set forth herein and there have
been no promises, inducements or commitments made in conjunction with this
Agreement and Release which are not explicitly set forth herein.

         15. THE UNDERSIGNED HEREBY ACKNOWLEDGE THAT THEY HAVE READ THIS
AGREEMENT AND RELEASE, CONFERRED WITH THEIR ATTORNEYS, AND UNDERSTAND THAT, BY
SIGNING THIS AGREEMENT, THEY HAVE MADE THE COMMITMENTS AND RELEASED THEIR RIGHTS
AS STATED ABOVE.

         16. The undersigned intend for the party, upon behalf of which they
execute, to be legally bound by this Agreement and Release and have read,
signed, sealed and delivered it voluntarily, without coercion, with knowledge of
the nature and consequences thereof and with the power to legally commit that
party.

                          MYCOGEN CORPORATION and/or DOW
                          AGROSCIENCES LLC




                          DEMETER BIOTECHNOLOGIES, LTD and/or DEMEGEN, INC.





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