**SATISFACTION
      AND PURCHASE AGREEMENT**




THIS
      SATISFACTION AND PURCHASE AGREEMENT (this “ **Agreement** ”)
      is
      made as of the 28th day of April, 2006 and effective as of January 1, 2006
      (the
“ **Effective
      Date** ”)
      by and
      between **Dyadic
      International, Inc.** ,
      a
      Delaware, USA corporation (“ **Dyadic
      Parent** ”),
      its
      wholly-owned subsidiary, Geneva Investment Holdings Limited, a British Virgin
      Islands corporation (“ **Geneva** ”)
      and
      its majority owned subsidiary, Puridet (Asia) Limited, a Hong Kong corporation
      (the “ **A-Subsidiary** ”
and
      together with Dyadic Parent and Geneva, the “ **Dyadic
      Parties** ”),
      Robert Albert Smeaton (“ **Smeaton** ”)
      and
      Raymond Tsang (“ **Tsang** ”).
      The
      Dyadic Parties, Smeaton and Tsang are sometimes hereinafter collectively
      referred to as the “ **Parties** ”
and
      individually as a “ **Party** .”
      Certain capitalized terms not expressly defined elsewhere herein are defined
      in
      the glossary appearing in Article V hereof.




**RECITALS:**




A.  Geneva,
      the Subsidiary and Smeaton are parties to that certain Agreement dated October
      21, 1998 with Raymond Chih Chung Kwong (“ **Kwong** ”)
      pertaining to Geneva’s purchase of a majority of the A-Subsidiary’s issued and
      outstanding shares of capital stock from Smeaton and Kwong (the “ **First
      Stock Purchase Agreement** ”).




B.  As
      of the
      date of this Agreement, the 200 issued and outstanding shares of the
      A-Subsidiary are owned 82.5% by Geneva, 12.5% by Smeaton and 5.0% by Tsang
      (the
      share of the A-Subsidiary owned by Smeaton and Tsang beings sometimes
      hereinafter collectively referred to as the “ **Subsidiary
      Minority Shares** ”).




C.  Under
      the
      terms of the First Stock Purchase Agreement, Smeaton is owed $405,000 as the
      unpaid balance of the purchase price due him from Geneva for the shares of
      the
      A-Subsidiary stock Geneva purchased from him upon the occurrence of certain
      events which have not yet obtained (the “ **Unpaid
      Purchase Price Obligation** ”),
      and
      the Parties wish to satisfy in full the Unpaid Purchase Price Obligation to
      Smeaton by providing for the payment to him of the sum of $405,000 (the
“ **Settlement
      Amount** ”).




D.  Smeaton
      and Tsang have each made loans to the A-Subsidiary, the current unpaid principal
      and interest owed by the A-Subsidiary hereunder being, as of the Effective
      Date,
      $122,846 of principal and $ 49,901 of interest in the case of Smeaton (the
      “ **Smeaton
      Loan Balance** ”)
      and
      $49,139 of principal and $19,968 of interest in the case of Tsang (the
“ **Tsang
      Loan Balance** ”
and
      together with the Smeaton Loan Balance, collectively, the “ **Loan
      Balances** ”).




E.  Geneva
      wishes to purchase from Smeaton and Tsang, all of the A-Subsidiary Minority
      Shares in consideration for $109,390 in the case of Smeaton (the “ **Smeaton
      Minority Share Purchase Price Amount** ”)
      and
      $43,756, in the case of Tsang (the “ **Tsang
      Minority Share Purchase Price Amount** ”
and
      together with the Smeaton Redemption Amount, the “ **Minority
      Share Purchase Price Amounts** ”).




F.  The
      Dyadic Parties wish to pay the aggregates sum of the Settlement Amount, the
      Loan
      Balances and the Minority Share Purchase Price Amounts (such aggregate sum
      being
      sometimes hereinafter collectively referred to as the “ **Total
      Payment Amount** ”)
      partially in the form of cash and partially in the form of shares of Common
      Stock of Dyadic Parent (the “ **Parent
      Shares** ”),
      all
      upon and subject to the terms and conditions of this Agreement.




G.  Smeaton
      wishes to settle the Unpaid Purchase Price Obligation with the Dyadic Parties,
      each of Smeaton and Tsang wish to receive payment in full of their respective
      Loan Balances and each of







Smeaton
      and Tsang wish to sell all of their A-Subsidiary Minority Shares to Geneva,
      for
      an aggregate consideration in the amount of the Total Payment Amount, by
      accepting payment thereof partially in immediately available funds and partially
      in Parent Shares, all upon and subject to the terms and conditions of this
      Agreement, provided
      that :
      (i) the
      payments of the Settlement Amount and the Minority Share Purchase Price Amounts,
      whether in the form of cash or in the form of Parent Shares, shall be for the
      account of Geneva only (and Geneva and Dyadic Parent have agreed that the that
      to the extent that Dyadic Parent pays the Settlement Amount and the Minority
      Share Purchase Price Amounts, an inter-company loan from Dyadic Parent to Geneva
      shall be deemed to be created on such terms as Geneva and Dyadic Parent may
      agree upon; and (ii) payment of the Loan Balances shall be made by Dyadic Parent
      and shall be deemed to give rise to a loan bearing the lowest rate of interest
      permitted by applicable US and Hong Kong laws by Dyadic Parent to the
      A-Subsidiary, payable upon demand.




H.  References
      to $ means United States dollars.




**AGREEMENT:**




NOW
      THEREFORE, in consideration of the foregoing Recitals (which are incorporated
      into this Agreement and made a part hereof), the covenants and agreements of
      the
      Parties herein below set forth and other good and valuable consideration, the
      receipt and sufficiency of which the Parties hereby each mutually acknowledge,
      the Parties, for themselves and their respective successors and assigns, agree
      as follows:




**ARTICLE
      I**




**SETTLEMENT
      OF UNPAID PURCHASE PRICE, PAYMENT OF LOAN BALANCES AND PURCHASE OF SUBSIDIARY
      MINORITY SHARES**




**1.1**  **Settlement
      of Unpaid Purchase Price and Termination of First Stock Purchase
      Agreement**




For
      and
      in full satisfaction of all of the obligations of the Dyadic Parties to Smeaton
      arising under and created by the First Stock Purchase Agreement, including
      by
      way of illustration, and not in limitation, the Unpaid Purchase Price
      Obligation, within five (5) days following the execution and delivery of this
      Agreement by the Parties, Geneva shall pay or cause to be paid to Smeaton the
      Settlement Amount ($405,000), which Settlement Amount is a part of and included
      in the Total Payment Amount, to be paid as provided in Section 1.4 hereof.
      Following Smeaton’s receipt of the Total Purchase Price, each of the Dyadic
      Parties, on the one hand, and Smeaton, on the other hand, expressly acknowledges
      and agree that as of the Effective Date, all of the rights and all of the
      obligations of the Dyadic Parties and Smeaton owing to the other created by
      or
      arising under the First Stock Purchase Agreement are satisfied in
      full.




**1.2**  **Payment
      of Loan Balances**




For
      and
      in full satisfaction of the entirety of the Smeaton Loan Balance owed Smeaton
      as
      of the Effective Date ($172,747), and for and in full satisfaction of the
      entirety of the Tsang Loan Balance owed Tsang as of the Effective Date
      ($69,107), within five (5) days following the execution and delivery of this
      Agreement by the Parties, Dyadic Parent shall lend the A-Subsidiary an amount
      sufficient to enable the Subsidiary to pay, and immediately thereupon, the
      A-Subsidiary shall remit, to Smeaton the Smeaton Loan Balance, and to Tsang,
      the
      Tsang Loan Balance, which sums are a part of and included in the Total Payment
      Amount, to be paid as provided in Section 1.4 hereof.




**1.3**  **Purchase
      and Sale of Subsidiary Minority Shares**




Each
      of
      Smeaton and Tsang, as legal and beneficial owners, hereby sell to Geneva, and
      Geneva hereby purchases from Smeaton and Tsang, all of the Subsidiary Minority
      Shares owned by them, free and clear of all encumbrances or third party rights
      or claims of any nature whatsoever, in consideration for, in the case of
      Smeaton, the Smeaton




Minority
      Redemption Amount ($109,390), and in the case of Tsang, the Tsang Minority
      Redemption Amount ($43,756), which Aggregate Subsidiary Minority Share Purchase
      Price are a part of and included in the Total Payment Amount, to be paid as
      provided in Section 1.4 hereof. Concurrently with the execution and delivery
      of
      this Agreement, each of Smeaton and Tsang shall deliver to Geneva at the offices
      of its legal counsel, Gavin Nesbitt, Esq., Deacons, 5 th Floor
      Alexandria House, 18 Charter Road, Central, Hong Kong DX-009010 Central 1:
      (i)
      instruments of transfer of the Subsidiary Minority Shares to Geneva; (ii) share
      certificates evidencing all of the Subsidiary Minority Shares; and (iii) sold
      notes in respect of the sale of the Subsidiary Minority Shares. The Dyadic
      Parties shall pay the entire ad valorem stamp duty on the purchase and sale
      of
      all of the Subsidiary Minority Shares. The Dyadic Parties expressly agree that
      the Chief Financial Officer of Dyadic-Parent, Mr. Wayne Moor, shall sign the
      instruments of transfer and bought notes on behalf of Geneva, as
      required.


**2**


**1.4**  **Dyadic
      Parties Payment of Total Payment Amount**




The
      Total
      Payment Amount shall be paid by Dyadic Parent and\or Geneva as follows: (a)
      by
      the wire transfers of Dyadic Parent and\or Geneva immediately available funds
      to
      each of Smeaton and Tsang in the aggregate amount of $375,000 (the “ **Total
      Cash Amount** ”),
      $325,000 to Smeaton and $50,000 to Tsang, within one (1) business day following
      the execution and delivery of this Agreement by the Parties; and (b) by Dyadic
      Parent’s delivery of an irrevocable letter of direction to its stock transfer
      agent to issue 212,501 Parent Shares (the “ **Total
      Share Amount** ”),
      181,069 Parent Shares to Smeaton, and 31,432 Parent Shares to Tsang.




**1.5**  **Mutual
      General Releases of Smeaton and Dyadic Parties**




(a)  Smeaton,
      for himself and his estate, personal representatives, assigns and
      successors-in-interest (each a “ **Smeaton
      Releasor** ”),
      hereby releases and discharges each of the Dyadic Parties and their respective
      shareholders, directors, officers, employees, agents, successors and assigns
      (each a “ **Dyadic
      Released Party** ”)
      of and
      from any and all claims or liabilities of any kind whatsoever, whether or not
      by
      contract and whether or not in law or in equity, which any Smeaton Releasor
      ever
      had, may now have or could ever have, or may have, known or unknown, accrued
      or
      unaccrued, fixed or contingent, in existence on the Effective Date, against
      any
      Dyadic Released Party, for or upon any matter, cause or thing relating to or
      connected in any manner with anything in existence on the Effective Date, except :
      (i) any
      obligations and liabilities of the A-Subsidiary to Smeaton arising by reason
      of
      his employment by the A-Subsidiary or under the that certain real estate lease
      dated November 3, 2005 by and between Smeaton and the A-Subsidiary (The
“ **Smeaton
      Lease** ”);
      (ii)
      all obligations and liabilities of Dyadic Parent to Smeaton in respect of Parent
      Shares acquired by him pursuant to all other subscription agreements between
      Dyadic Parent and Smeaton pertaining to his prior purchase of Parent Shares;
      and
      (iii) any obligations and liabilities of the Dyadic Parties to Smeaton created
      by the provisions of this Agreement.




(b)  Each
      of
      the Dyadic Parties, for themselves and their respective shareholders, directors,
      officers, employees, agents, successors and assigns (each a “ **Dyadic
      Releasor** ”),
      hereby releases and discharges each of Smeaton and his estate, personal
      representatives, assigns and successors-in-interest (each a “ **Smeaton
      Released Party** ),
      of and
      from any and all, claims or liabilities of any kind whatsoever, whether or
      not
      by contract and whether or not in law or in equity, which any Dyadic Releasor
      ever had, may now have or could ever have, or may have, known or unknown,
      accrued or unaccrued, fixed or contingent, in existence on the Effective Date,
      against any Smeaton Released Party, for or upon any matter, cause or thing
      relating to or connected in any manner with anything in existence on the
      Effective Date, except :
      (i) any
      obligations and liabilities of Smeaton to the A-Subsidiary by reason of his
      employment by the A-Subsidiary or the terms of the Smeaton Lease; (ii) all
      obligations and liabilities of Smeaton to Dyadic Parent in respect of Parent
      Shares acquired by him pursuant to all other subscription




(c)  agreements
      between Dyadic Parent and Smeaton pertaining to his prior purchase of Parent
      Shares; and (iii) any obligations and liabilities of Smeaton to the Dyadic
      Parties created by the provisions of this Agreement.




**1.6**  **Mutual
      General Releases of Tsang and Dyadic Parties**




(a)  Tsang,
      for himself and his estate, personal representatives, assigns and
      successors-in-interest (each a “ **Tsang
      Releasor** ”),
      hereby releases and discharges each Dyadic Released Party of and from any and
      all, claims or liabilities of any kind whatsoever, whether or not by contract
      and whether or not in law or in equity, which any Tsang Releasor ever had,
      may
      now have or could ever have, or may have, known or unknown, accrued or
      unaccrued, fixed or contingent, in existence on the Effective Date, against
      any
      Dyadic Released Party, for or upon any matter, cause or thing relating to or
      connected in any manner with anything in existence on the Effective Date, except :
      (i)  any
      obligations and liabilities of the A-Subsidiary to Tsang arising by reason
      of
      his employment by the A-Subsidiary; and (ii) any obligations and liabilities
      of
      the Dyadic Parties to Tsang created by the provisions of this
      Agreement.




(b)  Each
      Dyadic Releasor hereby releases and discharges each of Tsang and his estate,
      personal representatives, assigns and successors-in-interest (each a
“ **Tsang
      Released Party** ),
      of and
      from any and all, claims or liabilities of any kind whatsoever, whether or
      not
      by contract and whether or not in law or in equity, which any Dyadic Releasor
      ever had, may now have or could ever have, or may have, known or unknown,
      accrued or unaccrued, fixed or contingent, in existence on the Effective Date,
      against any Tsang Released Party, for or upon any matter, cause or thing
      relating to or connected in any manner with anything in existence on the
      Effective Date, except :
      (i) any
      obligations and liabilities of Tsang to the A-Subsidiary by reason of his
      employment by the A-Subsidiary; and (ii) any obligations and liabilities of
      Tsang to the Dyadic Parties created by the provisions of this
      Agreement.




**3**


**ARTICLE
      II**




**ISSUANCE
      OF PARENT SHARES TO SMEATON AND TSANG**




**2.1**  **Purchase
      and Sale of Parent Shares**




Pursuant
      to the provisions of Section 1.4 hereof, but subject to the provisions of this
      Article II and the restrictions imposed by applicable US securities laws, as
      set
      forth in Section 3.3 hereof: (a) Smeaton hereby purchases from Dyadic Parent,
      and Dyadic Parent hereby sells to Smeaton 181,069 Parent Shares; and (b) Tsang
      hereby purchases from Dyadic Parent, and Dyadic Parent hereby sells to Tsang
      31,432 Parent Shares.




**2.2**  **Smeaton
      and Tsang Securities Representations and Warranties**




In
      connection with Smeaton’s and Tsang’s purchase of the Parent Shares, they each
      hereby severally, and not jointly and severally, make
      the
      following representations and warranties to the Dyadic Parties:




(a)  each
      has
      such knowledge and experience in financial and business matters in general
      and
      with respect to businesses of a nature similar to Dyadic Parent so as to be
      capable of evaluating the merits and risks of, and making an informed business
      decision with respect to, the acquisition of the Parent Shares;




(b)  each
      is
      acquiring the Parent Shares solely for its own account and not with a view
      to or
      for resale in connection with any distribution or public offering thereof,
      within the meaning of any applicable securities laws and regulations, unless
      such distribution or offering is registered under the Securities Act of 1933,
      as
      amended (the “Securities Act”), or an exemption from such registration is
      available;




(c)  each
      (i) has received all the information it has deemed necessary to make an
      informed investment decision with respect to an acquisition of the Parent
      Shares; (ii) understands that Dyadic Parent is subject to the reporting
      requirements of the Securities Exchange Act of 1934, as amended (the “Exchange
      Act”), and has had the opportunity to review all publicly available filings made
      by Dyadic Parent with the Securities and Exchange Commission (the “SEC”)
      pursuant to either the Securities Act or the Exchange Act; (iii) has had
      the unrestricted opportunity to make such investigation as it has desired
      pertaining to Dyadic Parent and the acquisition of the Parent Shares and to
      verify the information that is, and has been, available to Smeaton and Tsang;
      and (iv) has had the opportunity to ask questions of Dyadic Parent
      concerning Dyadic Parent;




(d)  each is
      an
“accredited investor” within the meaning of the Securities Act, is able to bear
      the economic risk of its investment in the Parent Shares for an indefinite
      period of time;




(e)  each
      has
      received no public solicitation or advertisement with respect to the Parent
      Shares; and




(f)  each
      understands that the Parent Shares are "restricted securities" as that term
      is
      defined in Rule 144 promulgated by the SEC under the Securities Act, the resale
      of these Parent Shares is restricted by federal and state securities laws and,
      accordingly, the Parent Shares must be held indefinitely unless their resale
      is
      subsequently registered under the Securities Act, effectuated pursuant to Rule
      144, or Dyadic Parent receives an opinion of counsel acceptable to Dyadic Parent
      or another exemption from such registration is available for their
      resale.




**2.3**  **Restrictions
      on Transfer of Parent Shares**




Each
      of
      Smeaton and Tsang acknowledges and consents that certificates now or hereafter
      issued for the Parent Shares shall bear a legend with respect to the transfer
      restrictions under the Securities Act. Each of Smeaton and Tsang further agrees
      that if the Parent Shares or any portion thereof are subsequently transferred,
      he will execute, deliver and file all such papers, documents and instruments
      as
      may be required by the SEC and any applicable state securities commission to
      qualify the transfer for an exemption from registration under the Securities
      Act, or any applicable state securities laws, respectively, to the extent that
      such papers, documents and instruments may be necessary for such transfer.
      Each
      of Smeaton and Tsang also agrees to furnish Dyadic Parent with a copy of all
      such papers, documents and instruments, and, in addition, will furnish Dyadic
      Parent with any other information that


**4**




Dyadic
      Parent may reasonably require to ensure that no subsequent transfer or
      disposition of the Parent Shares by Smeaton or Tsang, as the case may be, is
      in
      violation of the Securities Act or any applicable US state or Hong Kong
      securities laws. Each of Smeaton and Tsang further acknowledges that it is
      aware
      that stop-transfer instructions may be given to the transfer agent of the Parent
      Shares to prevent any illegal transfer of the Parent Shares. For purposes
      hereof, the term resale includes any transfer for value including the mortgage,
      pledge or hypothecation of such Parent Shares.




**2.4 Piggyback
      Registration Rights of Smeaton and Tsang.** Smeaton and Tsang are
      hereby granted Dyadic Parent’s standard form piggyback registration rights,
      which are set forth in Exhibit A attached hereto and by this reference made
      a
      part hereof.




**ARTICLE
      III**




**REPRESENTATIONS
      AND WARRANTIES OF THE PARTIES**


**3.1**  **Dyadic
      Parties**




Each
      Dyadic Party, as regards itself, represents and warrants to Smeaton and Tsang
      that:




(a)  it is a duly organized corporation validly existing under the laws of
      the state or country of its incorporation and has the requisite power and
      authority to enter into and carry out the terms of this Agreement;




(b)  all
      corporate actions required to be taken by it to consummate this Agreement have
      been taken and no further approval of any board, court, or other body is
      necessary in order to permit it to consummate this Agreement; and




(c)  neither
      the execution and delivery of this Agreement, nor the performance or the
      compliance with this Agreement, has resulted (or will result) in any violation
      of, or be in conflict with, or invalidate, cancel, or make inoperative, or
      interfere with, or constitute a default under, any charter, bylaw, agreement,
      permit, judgment, decree or order, to which it is a party and there is no
      default and no event or omission has occurred which, but for the passing of
      time
      or the giving of notice, or both, would constitute a default on the part of
      any
      Party under this Agreement.




Dyadic
      Parent represents and warrants to Smeaton and Tsang that the Parent Shares
      issued to each of Smeaton and Tsang have been duly authorized for issuance
      and
      sale, have been validly issued and are fully-paid and
      non-assessable.




**3.2**  **Smeaton
      and Tsang**




Each
      of
      Smeaton and Tsang, severally, and not jointly and severally, hereby represents
      and warrants to each of the Dyadic Parties that:




(a)  he
      has
      the full power, authority and legal capacity to enter into this Agreement,
      and
      to perform his obligations hereunder;




(b)  neither
      his execution and delivery of this Agreement, nor his performance of or
      compliance with the terms and provisions of this Agreement, has resulted (or
      will result) in any violation of, or be in conflict with, or invalidate, cancel,
      or make inoperative, or interfere with, or constitute a default under any
      agreement to which he is a party;




(c)  upon
      his
      execution, delivery and performance of this Agreement, this Agreement shall
      be
      the valid and binding obligation of his, enforceable in accordance with its
      terms;




(d)  he
      is the
      record owner of, and has good and marketable title to, the Subsidiary Minority
      Shares he is selling to Geneva, free and clear of all encumbrances or third
      party rights or claims of any nature whatsoever;




(e)  since
      December 31, 2005, there has occurred no fact, event or circumstance which
      has
      had or would reasonably be expected to have a Material Adverse Effect on the
      business or operations of the A-Subsidiary and its Subsidiary;




(f)  the
      balance sheet of the A-Subsidiary and its Subsidiary as of December 31, 2005
      reflect all of the liabilities as of that date, and neither the A-Subsidiary
      nor
      its Subsidiary have any undisclosed liabilities of any kind
      whatsoever;


**5**


(g)  the
      A-Subsidiary and its Subsidiary have paid all Taxes properly owed when due
      and
      timely filed all Tax Returns required to be filed;




(h)  neither
      A-Subsidiary nor its Subsidiary has made any illegal payments of any kind to
      any
      other Person for purposes of doing business with such Person, and to the
      knowledge of
      either
      of Smeaton or Tsang, employees of neither the A-Subsidiary nor its Subsidiary
      have received any illegal payment from any Person for purposes of doing business
      with the A-Subsidiary or its Subsidiary;




(i)  each
      of
      the A-Subsidiary and its Subsidiary holds and is in compliance with all material
      permits, licenses, bonds, approvals, certificates, registrations, accreditations
      and other authorizations of all foreign, federal, state and local governmental
      agencies required for their conduct of their businesses and the ownership of
      their properties (including as the same relate to Environmental and Safety
      Requirements);




(j)  neither
      Smeaton nor Tsang is aware that any executive or key employee of the
      A-Subsidiary or its Subsidiary or any group of employees of the A-Subsidiary
      or
      its Subsidiary have any plans to terminate employment with the A-Subsidiary
      or
      its Subsidiary, as the case may be, and each of the A-Subsidiary and its
      Subsidiary have complied with all applicable laws, rules, and regulations
      relating to the employment of labor; and




(k)  except
      for the Smeaton Lease and the loans made by Smeaton and Tsang to the
      A-Subsidiary, there have been no contracts or transactions between the
      A-Subsidiary or its Subsidiary with Smeaton, Tsang or any of their
      Affiliates.




**ARTICLE
      IV**




**INDEMNIFICATION**




**4.1**  **Indemnification
      by Smeaton and Tsang** **.** Smeaton
      and Tsang, severally, and not jointly and severally, for themselves and their
      respective personal representatives, successors and assigns hereby agrees to
      protect, indemnify and hold each of the Dyadic Parties harmless of and from
      all
      loss, damage and expense, including reasonable attorneys’ and accountants fees
      and costs of investigation (collectively, “ **Damages** ”)
      arising out of the breach by either or Smeaton or Tsang of any of their
      respective representations, warranties and covenants set forth in this
      Agreement, provided that: (a) any claim for Damages made by any Dyadic Party
      in
      respect thereof must be made within two (2) years following the Effective Date;
      and (b) the maximum liability of each of Smeaton and Tsang to the Dyadic Parties
      pursuant to the provisions of this Section 4.1 shall not exceed: (i) in the
      case
      of Smeaton, the Smeaton Minority Share Purchase Price Amount; and (ii) in the
      case of Tsang, the Tsang Minority Share Purchase Price Amount.




**4.2**  **Indemnification
      by Geneva and Dyadic Parent** **.** Geneva
      and Dyadic Parent, jointly and severally, hereby agree to protect, indemnify
      and
      hold each of Smeaton and Tsang harmless of and from all loss, damage and
      expense, including reasonable attorneys’ and accountants fees and costs of
      investigation (collectively, “ **Damages** ”)
      arising out of the breach by any Dyadic Party of its representations, warranties
      and covenants set forth in this Agreement, provided that : (a) any claim for
      Damages made by any Dyadic Party in respect thereof must be made within two
      (2)
      years following the Effective Date; and (b) the maximum liability of Geneva
      and
      Dyadic Parent pursuant to the provisions of this Section 4.2 is $425,002.




**ARTICLE
      V**




**DEFINITIONS**




Capitalized
      terms not otherwise defined in this Agreement shall have the following
      meanings:




(a)**“Affiliate”** means a
        Person or entity, which directly or indirectly, through one or more
        intermediaries, controls, is controlled by, or is under common control with
        the
        Party specified.
  (b)  **“Material
        Adverse Effect”** means,
        with respect to any of the Dyadic Parties, as applicable, a material and
        adverse
        effect or development upon the business, assets, liabilities, financial
        condition, operating results, customer or supplier relations, employee
        relations, business prospects, cash flow or net worth of such Person and
        its
        Subsidiaries taken as a whole.


**6**




(c)  “ **Person** ”
means
      an individual, a partnership, a joint venture, a corporation, a trust, an
      estate, an unincorporated organization or a government or any department or
      agency thereof.




(d)  “ **Strategic
      Issuance** ”
means
      any issuance of Parent Shares (i) in connection with issuance of Parent Shares
      which are already the subject of an effective registration statement on file
      with the Securities and Exchange Commission on the date of this Agreement;
      (ii)
      a “corporate partnering” transaction or “strategic alliance,” as determined by
      the Board of Directors of Dyadic Parent, in good faith; (iii) in connection
      with
      any financing transaction in respect of which Dyadic Parent or any Affiliate
      is
      a borrower, or (iv) to a vendor, lender or customer of Dyadic Parent or any
      Affiliate, or a research, manufacturing or other commercial collaborator of
      Dyadic Parent or any Affiliate, in a transaction approved by the Board of
      Directors of Dyadic Parent in good faith.




(e)  “ **Subsidiary** ”
means,
      with respect to any Person, any corporation, partnership, limited liability
      company, association or other business entity of which (i) if a corporation,
      a
      majority of the total voting power of shares of stock entitled (irrespective
      of
      whether, at the time, stock of any other class or classes of such corporation
      shall have or might have voting power by reason of the happening of any
      contingency) to vote in the election of directors, managers or trustees thereof
      is at the time owned or controlled, directly or indirectly, by that Person
      or
      one or more of the other Subsidiaries of that Person or a combination thereof,
      or (ii) if a partnership, limited liability company, association or other
      business entity, either (A) a majority of the partnership or other similar
      ownership interest thereof is at the time owned or controlled, directly or
      indirectly, by that Person or one or more Subsidiaries of that Person or a
      combination thereof, or (B) such Person is a general partner, managing member
      or
      managing director of such partnership, limited liability company, association
      or
      other entity.




(f)  “ **Securities
      Act** ”
means
      the Securities Act of 1933, and regulations promulgated thereunder, as amended,
      or any similar federal law then in force.




(g)  **“Tax”** or **“Taxes”** means
      any federal, state, local or foreign income, gross receipts, franchise,
      estimated, alternative minimum, add-on minimum, sales, use, transfer,
      registration, value added, excise, natural resources, severance, stamp,
      occupation, premium, windfall profit, environmental, customs, duties, real
      property, personal property, capital stock, social security, unemployment,
      disability, payroll, license, employee, withholding or other tax of any kind
      whatsoever, including any interest, penalties or additions to tax or additional
      amounts in respect of the foregoing, and “ **Tax
      Return** ”
means
      any report or filing required to be made to any governmental authority in
      respect of any obligation to pay Taxes or report with respect to the computation
      thereof.


GENERAL
  **5.2**  **Announcements**
  Subject
        to any applicable statutory or regulatory rules, or otherwise as may be
        required, none of the Parties hereto shall make any public announcement in
        relation to the transactions the terms of which are set out in this Agreement or
        the transactions or arrangements hereby contemplated or herein referred to
        or
        any matter ancillary hereto or thereto without the prior consent of the other
        parties (which consent shall not be unreasonably withheld or
        delayed).
  **5.3**  **Costs**
  Each
        Party shall pay its own costs in relation to the negotiations leading up
        to the
        transactions which are the subject of this Agreement and the preparation,
        execution and carrying into effect of this Agreement. Notwithstanding anything
        herein provided, Smeaton and Tsang shall pay all ad valorem stamp duty on
        the
        sale of the Subsidiary Minority Shares, and the Dyadic Parties shall pay
        all ad
        valorem stamp duty on the purchase of the Parent Shares, as
        applicable.
  **5.4**  **Further
        Assurances**
  Each
        of
        the Parties undertakes to the other Parties that he or it will do all such
        acts
        and things and execute all such deeds and documents as may be necessary or
        desirable to carry into effect or to give legal effect to the provisions
        of this
        Agreement and the transactions hereby contemplated.
  **7**




**5.5**  **Assignment**
  Neither
        Smeaton nor Tsang shall assign or transfer, or purport to assign or transfer,
        any of their rights or obligations arising under this Agreement without the
        prior written consent of Dyadic Parent, in its absolute discretion,


but
      any
      of the Dyadic Parties may assign or transfer all or any part of its rights
      and
      obligations arising under this Agreement to any Affiliate, except for the
      obligation of Dyadic Parent to issue the Parent Shares and observe its
      obligations to Smeaton and Tsang set forth in Article III hereof.


**5.6**  **Notices.**




(a)  Any
      notices (which term shall include any other communication) required to be given
      under this Agreement or in connection with the matters contemplated by it shall,
      except where otherwise specifically provided, be in writing in the English
      language.




(b)  Any
      such
      notice shall be addressed as provided in Section 6.5(c) and may be:




(i)  personally
      delivered, in which case it shall be deemed to have been given upon delivery
      at
      the relevant address; or




(ii)  sent
      by
      pre-paid post, in which case it shall be deemed to have been given 7 days after
      the date of posting; or




(iii)  sent
      by
      facsimile, in which case it shall be deemed to have been given when dispatched,
      subject to confirmation of uninterrupted transmission by a transmission
      report.




(c)  The
      addresses and other details of the parties referred to in clause
      13.1(b):




Name:
              Address:
              
              Fax
                No.:
            Robert
                Albert Smeaton
              Blocks
                C-D, 2ndFloor, G. Lee Industrial Building, 77-81
              Chai
                Wan Kok Street, New Territories, Hong Kong
              (852)
                2411-1669Name:
              Address:
              
              Fax
                No.:
            Raymond
                Tsang
              Blocks
                C-D, 2ndFloor, G. Lee Industrial Building, 77-81
              Chai
                Wan Kok Street, New Territories, Hong Kong
              (852)
                2411-1669Name:
              Address:
              
              
              Fax
                No.:
            Geneva
                Investment Holdings Limited
              c/o
                Deacons
              5/F.,
                Alexandra House,
              18
                Chater Road, Central, Hong Kong
              (852)
                2810-0431Name:
              Address:
              
              Fax
                No.:
            Dyadic
                International, Inc.
              140
                Intracoastal Pointe Drive, Suite 404
              Jupiter,
                Florida 33477-5094
              Attn:
                Mark A. Emalfarb, Chief Executive Officer
              (561)
                743-7667Name:
              Address:
              
              Fax
                No.:
            A-Subsidiary
              Blocks
                C-D, 2ndFloor, G. Lee Industrial Building, 77-81
              Chai
                Wan Kok Street, New Territories, Hong Kong
              (852)
                2411-1669


or
      to
      such other address as shall, from time to time, be supplied in writing by any
      party to the other. Notices shall be deemed given on the date actually received
      by the addressee.




**5.7**  **Time
      of the Essence**




Time
      shall be of the essence of this Agreement.




**8**


5.8Governing
        Law
  This
        Agreement shall be governed by, and construed in accordance with, the laws of
        the Hong Kong Special Administrative Region.




**6.8**  **Dispute
      Resolution and Arbitration**




Except
      with respect to the enforcement of the covenants of Smeaton and Tsang set forth
      in Article IX hereof, as to which any Dyadic Party shall have the alternative
      right to elect to resort to any court of proper jurisdiction for the enforcement
      thereof and for relief in the form of any proper remedy that may be available
      thereunder, any dispute, controversy or claim arising out of or relating to
      this
      Agreement, or the breach termination or invalidity thereof, shall be settled
      by
      arbitration in accordance with the UNCITRAL Arbitration Rules as at present
      in
      force and as may be amended by the rest of this clause upon application by
      any
      party hereto to the Hong Kong International Arbitration Centre (“ **HKIAC** ”).
      The
      arbitration shall be conducted in the English language and the place of
      arbitration shall be in Hong Kong at the Hong Kong International Arbitration
      Centre. Any such arbitration shall be administered by HKIAC in accordance with
      HKIAC Procedures for Arbitration Rules as are therein contained. The decision
      of
      the arbitrators (by rule of majority) shall be final and binding on the parties
      (including any decision on their fees).




**6.9**  **Miscellaneous
      Provisions**




Whenever
      possible, each provision of this Agreement will be interpreted in such manner
      as
      to be effective and valid under applicable law, but if any provision of this
      Agreement is held to be invalid, illegal or unenforceable in any respect under
      any applicable law or rule in any jurisdiction, such invalidity, illegality
      or
      unenforceability will not affect any other provision or any other jurisdiction,
      but this Agreement will be reformed, construed and enforced in such jurisdiction
      as if such invalid, illegal or unenforceable provision had never been contained
      herein. This Agreement shall bind and inure to the benefit of the parties hereto
      and their respective successors and assigns.




This
      Agreement may be executed in counterparts, each of which shall be deemed an
      original and all of which, when taken together, shall constitute one and the
      same instrument.




This
      Agreement constitutes the whole agreement between the parties relating to the
      transactions hereby contemplated (no Party having relied on any representation
      or warranty made by any other Party which is not a term of this Agreement)
      and
      no future variation and/or waiver shall be effective unless made in writing
      and
      signed by each of the Parties. This Agreement shall supersede all and any
      previous agreements or arrangements between the Parties hereto or any of them
      relating to the A-Subsidiary or any other matter referred to in this Agreement
      and all or any such previous agreements or arrangements (if any ) shall cease
      and determine with effect from the date hereof, except for the Service Agreement
      between the A-Subsidiary and Smeaton dated October 21, 1998.




No
      change, modification or amendment of any provision of this Agreement shall
      be
      valid unless made in writing and signed by the Parties hereto; provided,
      however, that changes, modifications, or amendments to those provisions of
      this
      Agreement that apply only to a single Party need only be signed by that
      Party.




The
      waiver by a Party of a breach of any provision of this Agreement by another
      Party shall not operate or be construed as a waiver of any subsequent breach
      by
      that other Party.




The
      headings of this Agreement are inserted for convenience of reference only,
      and
      are not to be considered in the construction of the provisions hereof.




**9**




**IN
      WITNESS WHEREOF** ,
      the
      Parties hereto have executed this Agreement as of the date and year first above
      written.




DYADIC
                  INTERNATIONAL, INC.
              GENEVA
                  INVESTMENT HOLDINGS LIMITED
              PURIDET
                  (ASIA) LIMITEDBy:_____________________________
              By:__________________________
              By:_____________________________Name:
                  Mark A. Emalfarb
              Name:
                  Mark A. Emalfarb
              Name:
                  Mark A. EmalfarbTitle:
                  Chief Executive Officer
              Title:
                  President
              Title:
                  Chief Executive OfficerROBERT
                  A. SMEATON
              RAYMOND
                  TSANG_________________________
              _______________________


**10**


**EXHIBIT
      A**




**SMEATON
      AND TSANG PIGGYBACK REGISTRATION RIGHTS**




**1.**  **Notice
      of Registration of Dyadic Parent Securities**




Dyadic
      Parent hereby covenants and agrees that in the event it shall take action to
      register any of its securities under the Securities Act at any time during
      the
      two (2) year period following the Effective Date other than in the case of
      a
      registration being undertaken for the purpose of registering “Excluded
      Securities” (as hereinafter defined), Dyadic Parent shall give each of Smeaton
      and Tsang and any other Person that, as of that date, had been granted piggyback
      registration rights by Dyadic Parent comparable to the piggyback registration
      rights granted to Smeaton and Tsang in this Exhibit
      A (for
      purposes hereof, Smeaton and Tsang and all other such holders being hereinafter
      referred to as “ **Rightsholders** ”)
      written notice of Dyadic Parent’s intention to take that action (the
“ **Registration
      Notice** ”).




**2.**  **Smeaton/Tsang
      Piggyback Rights**




Smeaton
      and Tsang (together with all other Rightsholders) shall have the right,
      exercisable by written notice to Dyadic Parent within forty-five (45) days
      following receipt of the Registration Notice from Dyadic Parent, to request
      the
      inclusion of all or such portion of the Parent Shares issued to them pursuant
      to
      this Agreement (and any additional Parent Shares which may be issued to them
      in
      respect thereof by way of stock split, stock dividend or otherwise) as either
      or
      both of Smeaton and Tsang may elect in such registration, at the expense of
      the
      Dyadic Parent (other than the commission costs of selling all such Parent
      Shares).




**3.**  **Registration
      Process**




. Dyadic
      Parent shall, subject to the provisions of this Exhibit
      A ,
      thereupon use its commercially reasonable efforts to (i) effect the registration
      of Smeaton’s and\or Tsang’s Parent Shares to the end that such registration
      under the Securities Act shall become and remain effective, (ii) cause any
      underwriting agreement relating to Dyadic Parent's securities to provide that
      Smeaton and\or Tsang shall have the right to sell his or their Parent Shares
      to
      the underwriters and that the underwriters shall purchase the Parent Shares
      at
      the price paid by the underwriters for the securities sold by Dyadic Parent,
      and
      (iii) keep each of Smeaton and Tsang advised in writing as to the initiation
      of
      each registration and as to the completion thereof, (iv) furnish such number
      of
      the registration statement and the prospectus included therein, including
      preliminary prospectuses and other documents incident thereto as Smeaton and
      Tsang from time to time may reasonably request, and (v) cause all Parent Shares
      covered by such registrations to be listed on each securities exchange on which
      similar securities issued Dyadic Parent are listed, provided that:




(a)  each
      of
      Smeaton and Tsang shall have timely executed and delivered the usual and
      customary agreement between Dyadic Parent, Smeaton, and\or Tsang (as the case
      may be) and the underwriters relating to the registration;




(b)  in
      no
      event shall Dyadic Parent be required to keep up to date or to supplement any
      prospectus more than nine (9) months after the effective date of the
      registration statement of which such prospectus is a part; and


(c)  if
      the
      registration contemplated by the Registration Notice consists of an underwritten
      offer and sale by Dyadic Parent for its own account of Dyadic Parent securities
      to be registered under the Securities Act, and the managing underwriters advise
      Dyadic Parent in writing that in their opinion the offering contemplated by
      the
      Registration Notice cannot be successfully completed if Dyadic Parent were
      to
      also register all of the “Registrable Shares” (as defined below) requested to be
      included in such registration by the Rightsholders, then Dyadic Parent will
      include in that registration: (i) first, any securities Dyadic Parent proposes
      to sell as contemplated by the Registration Notice, and (ii) second, that
      portion of the aggregate number of Parent Shares held by Smeaton and Tsang
      pursuant to Section 2 hereof and all other Rightsholders (collectively, the
      “ **Registrable
      Shares** ”),
      which
      in the opinion of such managing underwriters can successfully be sold, such
      number of Registrable Shares to be taken pro rata from the then Rightsholders
      on
      the basis of the total number of Registrable Shares then held by each of them,
      with further like pro rata allocations among the Rightsholders of Registrable
      Shares in the event that any Rightsholder has requested registration of less
      than all of the Registrable Shares then held by such Rightsholder.




**4.**  **Excluded
      Securities**




As
      used
      herein, the term “ **Excluded
      Securities** ”
shall
      mean securities of Dyadic Parent issued: (i) pursuant to a stock option or
      other
      compensatory equity compensation plan being maintained by Dyadic Parent for
      employees, directors or other consultants to Dyadic Parent and its Affiliates;
      (ii) for the purpose of effecting an acquisition by Dyadic Parent of (or the
      procurement by Dyadic Parent of the right to acquire) another Person, by merger,
      purchase of all or substantially all of the assets of such other Person or
      by
      other reorganization whereby Dyadic Parent ends up owning or will have the
      right
      to acquire, directly or indirectly, more than 50% of the voting power of such
      other Person; or (iii) pursuant to any Strategic Issuance.


**11**