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                                                                     EXHIBIT 4.2

                               FIRST AMENDMENT TO
                   BRIDGE AND CONSOLIDATED TERM LOAN AGREEMENT

     This First Amendment, dated as of June 7, 2002 (the "First Amendment"),
amending that certain Bridge and Consolidated Term Loan Agreement dated as of
March 18, 2002 (the "Agreement") by and among Donlar Corporation, Donlar
BioSyntrex Corporation ("Borrowers") and Tennessee Farmers Life Insurance
Company, collectively with its other lending affiliates (the "Lender"), is by
and among the Borrowers and the Lender.

     NOW THEREFORE, in consideration of the foregoing and other consideration
the receipt of which is hereby acknowledged, the parties hereto agree as
follows:

1.   Conversion Rights. Section 9 is hereby amended to add a new Section 9.12
     which shall read as follows:

          "SECTION 9.12 SENIOR CONVERTIBLE PREFERRED STOCK. Notwithstanding
          anything in this Section 9 to the contrary, in the event any reduction
          in the "Conversion Price" of the Donlar Corporation Senior Convertible
          Preferred Stock pursuant to the Certificate of Designation Senior
          Convertible Preferred Stock occurs, a corresponding immediate
          reduction to the Conversion Price of the Notes shall be effected."

2.   Definitions.  Appendix A is hereby amended to add a new definition which
     shall read as follows:

          "Certificate of Designation Senior Convertible Preferred Stock means
          that certain Certificate of Designation Senior Convertible Preferred
          Stock attached as Exhibit A to the First Amendment to Bridge and
          Consolidated Term Loan Agreement, dated as of May 7, 2002, which shall
          be filed with the Illinois Secretary of State on or before the
          effective date of the merger between Donlar and Donlar Bio
          contemplated by the Agreement(s) to Reorganize."

3.   General.

     (a)  Confirmation of the Agreement. Except as amended hereby, the Agreement
          shall remain in full force and effect and it hereby ratified and
          confirmed in all respects.

     (b)  References to the Agreement. Each reference in the Agreement to "this
          Agreement", "hereunder" or "hereof", or words of like import, and each
          reference to the Agreement in any and all instruments or documents
          provided for in the Agreement or delivered or to be delivered
          thereunder or in connection therewith, shall, except where the context
          otherwise requires, be deemed a reference to the Agreement as amended
          hereby.

     (c)  Defined Terms. Capitalized terms used herein which are not otherwise
          defined are used with the meanings ascribed to them in the Agreement.



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     IN WITNESS WHEREOF, the undersigned have caused this First Amendment to be
duly executed as of the date first above written.



                                    DONLAR CORPORATION



                                    By:
                                       -----------------------------------------
                                         Title:
                                               ---------------------------------



                                    DONLAR BIOSYNTREX CORPORATION



                                    By:
                                       -----------------------------------------
                                         Title:
                                               ---------------------------------



                                    THE TENNESSEE FARMERS LIFE INSURANCE COMPANY



                                    By:
                                       -----------------------------------------
                                         Title:
                                               ---------------------------------