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                                                                    Exhibit 10.6

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   American National Bank                                       Credit Agreement
and Trust Company of Chicago

           [LOGO]
BANK ONE Company

This agreement between American National Bank and Trust Company of Chicago, and
its successors and assigns, (the "Bank"), whose address is 111 E. Busse Avenue,
Mount Prospect, IL 60056, and Alltech Associates, Inc. (the "Borrower"), whose
address is 2051 Waukegan Road, Deerfield, IL 60015.

1.   Credit Facilities.

     1.1  Scope. This agreement governs Facility A, and, unless otherwise agreed
          to in writing by the Bank and the Borrower or prohibited by applicable
          law, governs the Credit Facilities.

     1.2  Facility A (Line of Credit). The Bank has approved a credit facility
          to the Borrower in the principal sum not to exceed $5,000,000.00 in
          the aggregate at any one time outstanding ("Facility A"). Credit under
          Facility A shall be repayable as set forth in a Line of Credit Note
          executed concurrently with this agreement, and any renewals,
          modifications or extensions thereof. The proceeds of Facility A shall
          be used for the following purpose: working capital.

     1.3  Borrowing Base. The aggregate principal amount of advances outstanding
          at any one time under Facility A shall not exceed the lesser of the
          Borrowing Base or $5,000,000.00. If at any time the aggregate
          principal amount of advances outstanding under Facility A exceeds the
          Borrowing Base, the Borrower shall immediately pay to the Bank an
          amount equal to the difference between such aggregate principal amount
          of advances and the Borrowing Base. "Borrowing Base" means the
          aggregate of:

          A. 80% of Domestic Eligible Accounts, not to exceed the aggregate of
          $5,000,000.00; plus

          B. 80% of Foreign Eligible Accounts, not to exceed the aggregate of
          $500,000.00; plus

          C. 45% of the value of Eligible Inventory, not to exceed the aggregate
          of $5,000,000.00. For purposes hereof value shall mean the lesser of
          the Borrower's cost thereof calculated on a first-in, first-out basis
          or the wholesale market value thereof.

2.   Definitions. As used in this agreement, the following terms have the
     following respective meanings:

     2.1  "Credit Facilities" means all extensions of credit from the Bank to
          the Borrower, whether now existing or hereafter arising, including but
          not limited to those described in Section 1.

     2.2  "Liabilities" means all obligations, indebtedness and liabilities of
          the Borrower to any one or more of the Bank, BANK ONE CORPORATION, and
          any of their subsidiaries, affiliates or successors, now existing or
          later arising, including, without limitation, all loans, advances,
          interest, costs, overdraft indebtedness, credit card indebtedness,
          lease obligations, or obligations relating to any Rate Management
          Transaction, all monetary obligations incurred or accrued during the
          pendency of any bankruptcy, insolvency, receivership or other similar
          proceedings, regardless of whether allowed or allowable in such
          proceeding, and all renewals, extensions, modifications,
          consolidations or substitutions of any of the foregoing, whether the
          Borrower may be liable jointly with others or individually liable as a
          debtor, maker, co-maker, drawer, endorser, guarantor, surety or
          otherwise, and whether voluntarily or involuntarily incurred, due or
          not due, absolute or contingent, direct or indirect, liquidated or
          unliquidated. The term "Rate Management Transaction" in this agreement
          means any transaction (including an agreement with respect thereto)
          now existing or hereafter entered into among the Borrower, the Bank or
          BANK ONE CORPORATION, or any of its subsidiaries or affiliates or
          their successors, which is a rate swap, basis swap, forward rate
          transaction, commodity swap, commodity option, equity or equity index
          swap, equity or equity index option, bond option, interest rate
          option, foreign exchange transaction, cap transaction, floor
          transaction, collar transaction, forward transaction, currency swap
          transaction, cross-currency rate swap transaction, currency option or
          any other similar transaction (including any option with respect to
          any of these transactions) or any combination thereof, whether linked
          to one or more interest rates, foreign currencies, commodity prices,
          equity prices or other financial measures.

     2.3  "Notes" means the Line of Credit Note(s) described in Section 1.

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     2.4  "Account" means a trade account, account receivable, other receivable,
          or other right to payment for goods sold or leased or services
          rendered owing to the Borrower (or to a third party grantor acceptable
          to the Bank).

     2.5  "Account Debtor" means the person or entity obligated upon an Account.

     2.6  "Affiliate" means any person, corporation or other entity directly or
          indirectly controlling, controlled by or under common control with the
          Borrower and any director or officer of the Borrower or any subsidiary
          of the Borrower.

     2.7  "Distributions" means all dividends and other distributions made by
          the Borrower to its shareholders, partners, owners or members, as the
          case may be, other than salary, bonuses, and other compensation for
          services expended in the current accounting period.

     2.8  "Domestic Eligible Accounts" means, at any time, all of the Borrower's
          Accounts which contain selling terms and conditions acceptable to the
          Bank. The net amount of any Eligible Account against which the
          Borrower may borrow shall exclude all returns, discounts, credits, and
          offsets of any nature. Unless otherwise agreed to by the Bank in
          writing, Eligible Accounts do not include Accounts: (1) with respect
          to which the Account Debtor is an employee or agent of the Borrower;
          (2) with respect to which the Account Debtor is affiliated with or
          related to the Borrower; (3) with respect to which goods are placed on
          consignment, guaranteed sale, or other terms by reason of which the
          payment by the Account Debtor may be conditional; (4) with respect to
          which the Account Debtor is not a resident of the United States,
          except to the extent such Accounts are supported by insurance, bonds
          or other assurances satisfactory to the Bank; (5) with respect to
          which the Borrower is or may become liable to the Account Debtor for
          goods sold or services rendered by the Account Debtor to the Borrower;
          (6) which are subject to dispute, counterclaim, or setoff; (7) with
          respect to which the goods have not been shipped or delivered, or the
          services have not been rendered, to the Account Debtor; (8) with
          respect to which the Bank, in its sole discretion, deems the
          creditworthiness or financial condition of the Account Debtor to be
          unsatisfactory; (9) of any Account Debtor who has filed or has had
          filed against it a petition in bankruptcy or an application for relief
          under any provision of any state or federal bankruptcy, insolvency, or
          debtor-in-relief acts; or who has had appointed a trustee, custodian,
          or receiver for the assets of such Account Debtor; or who has made an
          assignment for the benefit of creditors or has become insolvent or
          fails generally to pay its debts (including its payrolls) as such
          debts become due; (10) with respect to which the Account Debtor is the
          United States government or any department or agency of the United
          States; (11) which have not been paid in full within ninety (90) days
          from the invoice date and.(12) In no event will the balance of any
          Account of any single Account Debtor be eligible whenever the portion
          of the Account which has not been paid within ninety (90) days from
          the invoice date is in excess of 25% of the total amount outstanding
          on the Account.

     2.9  "Foreign Eligible Accounts" means, at any time, all of the Borrower's
          Accounts which contain selling terms and conditions acceptable to the
          Bank. The net amount of any Eligible Account against which the
          Borrower may borrow shall exclude all returns, discounts, credits, and
          offsets of any nature. Unless otherwise agreed to by the Bank in
          writing, Eligible Accounts do not include Accounts: (1) with respect
          to which the Account Debtor is an employee or agent of the Borrower;
          (2) with respect to which the Account Debtor is affiliated with or
          related to the Borrower; (3) with respect to which goods are placed on
          consignment, guaranteed sale, or other terms by reason of which the
          payment by the Account Debtor may be conditional; (4) with respect to
          which the Borrower is or may become liable to the Account Debtor for
          goods sold or services rendered by the Account Debtor to the Borrower;
          (5) which are subject to dispute, counterclaim, or setoff; (6) with
          respect to which the goods have not been shipped or delivered, or the
          services have not been rendered, to the Account Debtor; (7) with
          respect to which the Bank, in its sole discretion, deems the
          creditworthiness or financial condition of the Account Debtor to be
          unsatisfactory; (8) of any Account Debtor who has filed or has had
          filed against it a petition in bankruptcy or an application for relief
          under any provision of any state or federal bankruptcy, insolvency, or
          debtor-in-relief acts; or who has had appointed a trustee, custodian,
          or receiver for the assets of such Account Debtor; or who has made an
          assignment for the benefit of creditors or has become insolvent or
          fails generally to pay its debts (including its payrolls) as such
          debts become due; (9) with respect to which the Account Debtor is the
          United States government or any department or agency of the United
          States; (10) which have not been paid in full within one hundred
          twenty (120) days from the invoice date; and (11) In no event will the
          balance of any Account of any single Account Debtor be eligible
          whenever the portion of the Account which has not been paid within
          one hundred twenty (120) days from the invoice date is in excess of
          25% of the total amount outstanding on the Account.

     2.10 "Eligible Inventory" means, at any time, all of the Borrower's
          Inventory except: (1) Inventory which is not owned by the Borrower
          free and clear of all security interests, liens, encumbrances, and
          claims of third parties; (2) Inventory which the Bank, in its sole
          discretion, deems to be obsolete, unsalable, damaged, defective, or
          unfit for further processing; and (3) Work in process.

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     2.11   "Inventory" means all of the Borrower's raw materials, work in
            process, finished goods, merchandise, parts and supplies, of every
            kind and description, and goods held for sale or lease or furnished
            under contracts of service in which the Borrower now has or
            hereafter acquires any right, whether held by the Borrower or
            others, and all documents of title, warehouse receipts, bills of
            lading, and all other documents of every type covering all or any ?
            of the foregoing. Inventory includes inventory temporarily out of
            the Borrower's custody or possession and ? returns on Accounts.

     2.12   "Intangible Assets" means the aggregate amount of all assets
            classified as intangible assets under generally accepted accounting
            principles, including, without limitation, goodwill, trademarks,
            patents, copyrights, organization expenses, prepaid expenses,
            franchises, licenses, trade names, brand names, mailing lists,
            catalogs, excess of cost over book value of assets acquired, and
            bond discount and underwriting expenses.

     2.13   "Subordinated Debt" means debt subordinated to the Bank in manner
            and by agreement satisfactory to the Bank.

     2.14   "Tangible Capital Funds" means Tangible Net Worth plus Subordinated
            Debt less Intangibles.

     2.15   "Tangible Net Worth" means total assets less the sum of Intangible
            Assets, and total liabilities.

3.   Conditions Precedent.

     3.1    Conditions Precedent to Initial Extension of Credit. Before the
            first extension of credit governed by this agreement, whether by
            disbursement of a loan, issuance of a letter of credit, or
            otherwise, the Borrower shall deliver to the Bank, in form and
            substance satisfactory to the Bank:

            A.   Loan Documents. The Notes, and as applicable, the letter of
            credit applications, the security agreements, the pledge agreements,
            financing statements, mortgages or deeds of trust, the guaranties,
            the subordination agreements, and any other loan documents which the
            Bank may reasonably require to give effect to the transactions
            described in this agreement;

            B.   Evidence of Due Organization and Good Standing. Evidence,
            satisfactory to the Bank, of the ? organization and good standing of
            the Borrower and every other business entity that is a party to this
            agreement or any other loan document required by this agreement; and

            C.   Evidence of Authority to Enter into Loan Documents. Evidence
            that (i) each party to this agreement and any other loan document
            required by this agreement is authorized to enter into the
            transactions described in this agreement and the other loan
            documents, and (ii) the person signing on behalf of each such party
            is authorized to do.

     3.2    Conditions Precedent to Each Extension of Credit. Before any
            extension of credit governed by this agreement, whether by
            disbursement of a loan, issuance of a letter of credit or otherwise,
            the following conditions must be satisfied:

            A.   Representations. The representations of the Borrower are true
            on and as of the date of the extension of credit;

            B.   No Event of Default. No default has occurred in any provision
            of this agreement and is continuing or would result from the
            extension of credit, and no event has occurred which would
            constitute the occurrence of any default but for the lapse of time
            until the end of any grace or cure period; and

            C.   Additional Approvals, Opinions, and Documents. The Bank has
            received any other approvals, opinions and documents as it may
            reasonably request.

4.   Affirmative Covenants. The Borrower shall:

     4.1    Insurance. Maintain insurance with financially sound and reputable
            insurers covering its properties and business against those
            casualties and contingencies and in the types and amounts as are in
            accordance with sound business and industry practices.

     4.2    Existence. Maintain its existence and business operations as
            presently in effect in accordance with all applicable laws and
            regulations, pay its debts and obligations when due under normal
            terms, and pay on or before their due date, all taxes, assessments,
            fees and other governmental monetary obligations, except as they may
            be contested in good faith if they have been properly reflected on
            its books and, at the Bank's request, adequate funds or security has
            been pledged to insure payment.

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     4.3  Financial Records. Maintain proper books and records of account, in
          accordance with generally accepted accounting principles, and
          consistent with financial statements previously submitted to the Bank.

     4.4  Inspection. Permit the Bank to inspect and copy the Borrower's
          business records at such times and at such intervals as the Bank may
          reasonably require, and to discuss the Borrower's business,
          operations, and financial condition with the Borrower's officers and
          accountants.

     4.5  Financial Reports. Furnish to the Bank whatever information, books and
          records the Bank may reasonably request, including at a minimum:

          A. Within sixty (60) days after each quarterly period, a balance sheet
          as of the end of that period and statements of income, cash flow and
          retained earnings, from the beginning of that fiscal year to the end
          of that period, certified as correct by one of its authorized agents.

          B. Within one hundred and twenty (120) days after and as of the end of
          each of its fiscal years, a detailed financial statement including a
          balance sheet and statements of income, cash flow and retained
          earnings, such financial statement, to be audited by an independent
          certified public accountant of recognized standing acceptable to the
          Bank in the Bank's sole discretion.

          C. Within thirty (30) days after and as of the end of each calendar
          month, the following lists, each certified as correct by one of its
          authorized agents:

               (1)  a list of accounts receivable, aged from date of invoice,
                    and
               (2)  a list of inventory, valued at the lower of cost or market.

          D. Within thirty (30) days after each monthly period, the Borrower
          shall deliver to the Bank a borrowing base certificate, in form and
          detail satisfactory to the Bank, along with such supporting
          documentation as the Bank may request.

     4.6  Notices of Claims, Litigation, Defaults, etc. Promptly inform the Bank
          in writing of (1) all existing and all threatened litigation, claims,
          investigations, administrative proceedings and similar actions
          affecting the Borrower which could materially affect the financial
          condition of the Borrower; (2) the occurrence of any event which gives
          rise to the Bank's option to terminate the Credit Facilities; (3) the
          institution of steps by the Borrower to withdraw from, or the
          institution of any steps to terminate, any employee benefit plan as to
          which the Borrower may have liability; (4) any additions to or changes
          in the locations of the Borrower's businesses; and (5) any alleged
          breach of any provision of this agreement or of any other agreement
          related to the Credit Facilities by the Bank.

     4.7  Additional Information. Furnish such additional information and
          statements, as the Bank may request, from time to time.

     4.8  Insurance Reports. Furnish to the Bank, upon request of the Bank,
          reports on each existing insurance policy showing such information as
          the Bank may reasonably request.

     4.9  Other Agreements. Comply with all terms and conditions of all other
          agreements, whether now or hereafter existing, between the Borrower
          and any other party.

     4.10 Title to Assets and Property. Maintain good and marketable title to
          all of the Borrower's assets and properties.

     4.11 Additional Assurances. Make, execute and deliver to the Bank such
          other agreements as the Bank may reasonably request to evidence the
          Credit Facilities and to perfect any security interests.

     4.12 Employee Benefit Plans. Maintain each employee benefit plan as to
          which the Borrower may have any liability, in compliance with all
          applicable requirements of law and regulations.

     4.13 Depository Relationship. Maintain its primary banking relationship
          with the Bank and establish such accounts and maintain balances
          therein with the Bank sufficient to cover the cost of all the Bank's
          services provided; provided, however, that nothing herein shall
          require the Borrower to keep and maintain a specific minimum balance
          in such accounts.

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     4.14 Compliance Certificates. Provide the Bank, within sixty (60) days
          after the end of each fiscal quarter, with a certificate executed by
          the Borrower's chief financial officer, or other officer or a person
          acceptable to the Bank, certifying that, as of the date of the
          certificate, no default exists under any provision of this agreement.

5.   Negative Covenants.

     5.1  Unless otherwise noted, the financial requirements set forth in this
          section will be computed in accordance with generally accepted
          accounting principles applied on a basis consistent with financial
          statements previously submitted by the Borrower to the Bank.

     5.2  Without the written consent of the Bank, the Borrower will not:

          A. Dividends. Acquire or retire any of its shares of capital stock, or
          declare or pay dividends or make any other distributions upon any of
          its shares of capital stock, except in the absence of the occurrence
          of any default, dividends in its capital stock and dividends payable
          to "Sub-S" corporation shareholders sufficient in amount to pay their
          income tax obligation related to the Borrower's taxable income.

          B. Sale of Shares. Issue, sell or otherwise dispose of any shares of
          its capital stock or other securities, or rights, warrants or options
          to purchase or acquire those shares or securities.

          C. Debt. Incur, or permit to remain outstanding, debt for borrowed
          money or installment obligations, except debt reflected in the latest
          financial statement of the Borrower furnished to the Bank prior to
          execution of this agreement and not to be paid with proceeds of
          borrowings under the Credit Facilities. For purposes of this covenant,
          the sale of any account receivable is the incurring of debt for
          borrowed money.

          D. Guaranties. Guarantee or otherwise become or remain secondarily
          liable on the undertaking of another, except for endorsement of drafts
          for deposit and collection in the ordinary course of business.

          E. Liens. Create or permit to exist any lien on any of its property,
          real or personal, except: existing liens known to the Bank; liens to
          the Bank; liens incurred in the ordinary course of business securing
          current nondelinquent liabilities for taxes, worker's compensation,
          unemployment insurance, social security and pension liabilities.

          F. Use of Proceeds. Use, or permit any proceeds of the Credit
          Facilities to be used, directly or indirectly, for the purpose of
          "purchasing or carrying any margin stock" within the meaning of
          Federal Reserve Board Regulation U. At the Bank's request, the
          Borrower will furnish a completed Federal Reserve Board Form U-1.

          G. Continuity of Operations. (1) Engage in any business activities
          substantially different from those in which the Borrower is presently
          engaged; (2) cease operations, liquidate, merge, transfer, acquire or
          consolidate with any other entity, change its name, dissolve, or sell
          any assets out of the ordinary course of business; or (3) enter into
          any arrangement with any person providing for the leasing by the
          Borrower to any subsidiary of real or personal property which has been
          sold or transferred by the Borrower or subsidiary to such person.

          H. Limitation on Negative Pledge Clauses. Enter into any agreement
          with any person other than the Bank which prohibits or limits the
          ability of the Borrower or any of its subsidiaries to create or permit
          to exist any lien on any of its property, assets or revenues, whether
          now owned or hereafter acquired.

          I. Conflicting Agreements. Enter into any agreement containing any
          provision which would be violated or breached by the performance of
          the Borrower's obligations under this agreement.

          J. Transfer of Ownership. Permit any pledge of any ownership interest
          in the Borrower, or any sale or other transfer of any ownership
          interest in the Borrower.

          K. Tangible Capital Funds. Permit as of each fiscal quarter end, the
          Borrower and its subsidiaries' Tangible Capital Funds to be less than
          $3,500,000.00.

          L. Leverage Ratio. Permit as of each fiscal quarter end, the Borrower
          and its subsidiaries' ratio of total liabilities to Tangible Capital
          Funds to be greater than 3.75 to 1.00.

          M. Debt Service Coverage Ratio. Permit as of each fiscal quarter end,
          the Borrower and its subsidiaries' ratio of earnings before interest
          and taxes, plus depreciation, minus any distributions and unfunded
          capital expenditures,

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          for the three month period then ending to interest expense, prior
          period current maturities of long term debt and capital leases, to be
          less than 1.00 to 1.00.

6.   Representations.

     6.1  Representations by the Borrower. Each Borrower represents that: (a)
          the execution and delivery of this agreement and the Notes, and the
          performance of the obligations they impose, do not violate any law,
          conflict with any agreement by which it is bound, or require the
          consent or approval of any governmental authority or other third
          party, (b) this agreement and the Notes are valid and binding
          agreements, enforceable according to their terms, (c) all balance
          sheets, profit and loss statements, and other financial statements and
          other information furnished to the Bank in connection with the
          Liabilities are accurate and fairly reflect the financial condition of
          the organizations and persons to which they apply on their effective
          dates, including contingent liabilities of every type, which financial
          condition has not changed materially and adversely since those dates,
          (d) no litigation, claim, investigation, administrative proceeding or
          similar action (including those for unpaid taxes) against the Borrower
          is pending or threatened, and no other event has occurred which may in
          any one case or in the aggregate materially adversely affect the
          Borrower's financial condition and properties, other than litigation,
          claims, or other events, if any, that have been disclosed to and
          acknowledged by the Bank in writing, (e) all of the Borrower's tax
          returns and reports that are or were required to be filed, have been
          filed, and all taxes, assessments and other governmental charges have
          been paid in full, except those presently being contested by the
          Borrower in good faith and for which adequate reserves have been
          provided, (f) the Borrower is not a "holding company" or a company
          "controlled" by an "investment company", within the meaning of the
          Investment Company Act of 1940. as amended. (g) the Borrower is not a
          "holding company", or a "subsidiary company" of a "holding company" or
          an "affiliate" of a "holding company" or of a "subsidiary company" of
          a "holding company" within the meaning of the Public Utility Holding
          Company Act of 1935, as amended, (h) there are no defenses or
          counterclaims, offsets or adverse claims, demands or actions of any
          kind, personal or otherwise, that the Borrower could assert with
          respect to this agreement or the Credit Facilities, (i) the Borrower
          owns, or is licensed to use, all trademarks, trade names, copyrights,
          technology, know-how and processes necessary for the conduct of its
          business as currently conducted, and (j) no part of the proceeds of
          the Credit Facilities will be used for "purchasing" or "carrying" any
          "margin stock" within the respective meanings of each of the quoted
          terms under Regulation U of the Board of Governors of the Federal
          Reserve System of the United States (the "Board") as now and from time
          to time hereafter in effect or for any purpose which violates the
          provisions of any regulations of the Board. Each Borrower, other than
          a natural person, further represents that: (a) it is duly organized,
          existing and in good standing pursuant to the laws under which it is
          organized, and (b) the execution and delivery of this agreement and
          the Notes and the performance of the obligations they impose (i) are
          within its powers, (ii) have been duly authorized by all necessary
          action of its governing body, and (iii) do not contravene the terms of
          its articles of incorporation or organization, its by-laws, or any
          partnership, operating or other agreement governing its affairs.

     6.2  Representations Regarding Assets. With respect to any asset of the
          Borrower utilized in the calculation of the Borrowing Base set forth
          in this agreement, the Borrower represents and warrants to the Bank:
          (1) each asset represented by the Borrower to be eligible for
          Borrowing Base purposes of this agreement conforms to the eligibility
          definitions set forth in this agreement (2) all asset values delivered
          to the Bank will be true and correct, subject to immaterial variance;
          and be determined on a consistent accounting basis; (3) except as
          agreed to the contrary by the Bank in writing, each asset is now and
          at all times hereafter will be in the Borrower's physical possession
          and shall not be held by others on consignment, sale or approval, or
          sale or return; (4) except as reflected in schedules delivered to the
          Bank, each asset is now and at all times hereafter will be of good and
          merchantable quality, free from defects; (5) each asset is not now and
          will not at any time hereafter be stored with a bailee, warehouseman,
          or similar party without the Bank's prior written consent, and in such
          event, the Borrower will concurrently at the time of bailment cause
          any such bailee, warehouseman, or similar party to issue and deliver
          to the Bank, warehouseman receipts in the Bank's name evidencing the
          storage of the assets; and (6) the Bank, its assigns, or agents shall
          have the right at any time and at the Borrower's expense to inspect,
          examine and audit the Borrower's records, and if Accounts are included
          in the calculation of Borrowing Base, confirm with Account Debtors the
          accuracy of such Accounts, and inspect and examine the assets and
          to check and test the same as to quality, quantity, value, and
          condition.

7.   Default/Remedies. If any of the Credit Facilities are not paid at maturity,
     whether by acceleration or otherwise, or if a default by anyone occurs
     under the terms of this agreement, the Notes or any agreement related to
     the Credit Facilities, then the Bank shall have all of the rights and
     remedies provided by any law or agreement.

8.   Miscellaneous.

     8.1. Notice. Any notices and demands under or related to this document
          shall be in writing and delivered to the intended party at its address
          stated herein, and if to the Bank, at its main office if no other
          address of the Bank is specified herein,

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          by one of the following means: (a) by hand, (b) by a nationally
          recognized overnight courier service, or (c) by certified mail,
          postage prepaid, with return receipt requested. Notice shall be deemed
          given: (a) upon receipt if delivered by hand. (b) on the Delivery Day
          after the day of deposit with a nationally recognized courier service,
          or (c) on the third Delivery Day after the notice is deposited in the
          mail. "Delivery Day" means a day other than a Saturday, a Sunday or
          any other day on which national banking associations are authorized to
          be closed. Any party may change its address for purposes of the
          receipt of notices and demands by giving notice of such change in the
          manner provided in this provision.

     8.2  No Waiver. No delay on the part of the Bank in the exercise of any
          right or remedy waives that right or remedy. No single or partial
          exercise by the Bank of any right or remedy precludes any other future
          exercise of it or the exercise of any other right or remedy. No waiver
          or indulgence by the Bank of any default is effective unless it is in
          writing and signed by the Bank, nor shall a waiver on one occasion bar
          or waive that right on any future occasion.

     8.3  Integration. This agreement, the Notes, and any agreement related to
          the Credit Facilities embody the entire agreement and understanding
          between the Borrower and the Bank and supersede all prior agreements
          and understandings relating to their subject matter. If any one or
          more of the obligations of the Borrower under this agreement or the
          Notes is invalid, illegal or unenforceable in any jurisdiction, the
          validity, legality and enforceability of the remaining obligations of
          the Borrower shall not in any way be affected or impaired, and the
          invalidity, illegality or unenforceability in one jurisdiction shall
          not affect the validity, legality or enforceability of the obligations
          of the Borrower under this agreement or the Notes in any other
          jurisdiction.

     8.4  Joint and Several Liability. Each Borrower, if more than one, is
          jointly and severally liable.

     8.5  Governing Law and Venue. This agreement is delivered in the State of
          Illinois and governed by Illinois law (without giving effect to its
          laws of conflicts). The Borrower agrees that any legal action or
          proceeding with respect to any of its obligations under this agreement
          may be brought by the Bank in any state or federal court located in
          the State of Illinois, as the Bank in its sole discretion may elect.
          By the execution and delivery of this agreement, the Borrower submits
          to and accepts, for itself and in respect of its property, generally
          and unconditionally, the non-exclusive jurisdiction of those courts.
          The Borrower waives any claim that the State of Illinois is not a
          convenient forum on the proper venue for any such suit, action or
          proceeding.

     8.6  Captions. Section headings are for convenience of reference only and
          do not affect the interpretation of this agreement.

     8.7  Subsidiaries and Affiliates of the Borrower. To the extent the context
          of any provisions of this agreement makes it appropriate, including
          without limitation any representation, warranty or covenant, the word
          "Borrower" as used in this agreement shall include all of the
          Borrower's subsidiaries and affiliates. Notwithstanding the foregoing,
          however, under no circumstances shall this agreement be construed to
          require the Bank to make any loan or other financial accommodation to
          any of the Borrower's subsidiaries or affiliates.

     8.8  Survival of Representations and Warranties. The Borrower understands
          and agrees that in extending the Credit Facilities, the Bank is
          relying on all representations, warranties, and covenants made by the
          Borrower in this agreement or in any certificate or other instrument
          delivered by the Borrower to the Bank under this agreement. The
          Borrower further agrees that regardless of any investigation made by
          the Bank, all such representations, warranties and covenants will
          survive the making of the Credit Facilities and delivery to the Bank
          of this agreement, shall be continuing in nature, and shall remain in
          full force and effect until such time as the Borrower's indebtedness
          to the Bank shall be paid in full.

     8.9  Non-Liability of the Bank. The relationship between the Borrower and
          the Bank created by this agreement is strictly a debtor and creditor
          relationship and not fiduciary in nature, nor is the relationship to
          be construed as creating any partnership or joint venture between the
          Bank and the Borrower. The Borrower is exercising the Borrower's own
          judgement with respect to the Borrower's business. All information
          supplied to the Bank is for the Bank's protection only and no other
          party is entitled to rely on such information. There is no duty for
          Bank to review, inspect, supervise or inform the Borrower of any
          matter with respect to the Borrower's business. The Bank and the
          Borrower intend that the Bank may reasonably rely on all information
          supplied by the Borrower to the Bank, together with all
          representations and warranties given by the Borrower to the Bank,
          without investigation or confirmation by the Bank and that any
          investigation or failure to investigate will not diminish the Bank's
          right to so rely.

     8.10 Indemnification of the Bank. The Borrower agrees to indemnify, defend
          and hold the Bank and BANK ONE CORPORATION, or any of its subsidiaries
          or affiliates or their successors, and each of their respective
          shareholders, directors, officers, employees and agents (collectively,
          the "Indemnified Persons") harmless from any and all obligations,
          claims, liabilities, losses, damages, penalties, fines, forfeitures,
          actions, judgments, suits, costs,

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<PAGE>

          expenses and disbursements of any kind or nature (including, without
          limitation, any Indemnified Person's attorneys' fees) (collectively,
          the "Claims") which may be imposed upon, incurred by or assessed
          against any Indemnified Person (whether or not caused by any
          Indemnified Person's sole, concurrent, or contributory negligence)
          arising out of or relating to this agreement; the exercise of the
          rights and remedies granted under this agreement (including, without
          limitation, the enforcement of this agreement and the defense of any
          Indemnified Persons action or inaction in connection with this
          agreement); and in connection with the Borrower's failure to perform
          all of the Borrower's obligations under this agreement, except to the
          limited extent that the Claims against any such Indemnified Person are
          proximately caused by such Indemnified Person's willful misconduct.
          The indemnification provided for in this section shall survive the
          termination of this agreement and shall extend to and continue to
          benefit each individual or entity who is or has at any time been an
          Indemnified Person.

          The Borrower's indemnity obligations under this section shall not in
          any way be affected by the presence or absence of covering insurance,
          or by the amount of such insurance or by the failure or refusal of any
          insurance carrier to perform any obligation on its part under any
          insurance policy or policies affecting the Borrower's assets or the
          Borrower's business activities. Should any Claim be made or brought
          against any Indemnified Person by reason of any event as to which the
          Borrower's indemnification obligations apply, then, upon any
          Indemnified Person's demand, the Borrower, at its sole cost and
          expense, shall defend such Claim in the Borrower's name, if necessary,
          by the attorneys for the Borrower's insurance carrier (if such Claim
          is covered by insurance), or otherwise by such attorneys as any
          Indemnified Person shall approve. Any Indemnified Person may also
          engage its own attorneys at its reasonable discretion to defend the
          Borrower and to assist in its defense and the Borrower agrees to pay
          the fees and disbursements of such attorneys.

     8.11 Counterparts. This agreement may be executed in multiple counterparts,
          each of which, when so executed, shall be deemed an original, but all
          such counterparts, taken together, shall constitute one and the same
          agreement.

     8.12 Sole Discretion of the Bank. Whenever the Bank's consent or approval
          is required under this agreement, the decision as to whether or not to
          consent or approve shall be in the sole and exclusive discretion of
          the Bank and the Bank's decision shall be final and conclusive.

     8.13 Advice of Counsel. The Borrower acknowledges that it has been advised
          by counsel, or had the opportunity to be advised by counsel, in the
          negotiation, execution and delivery of this agreement and any
          documents executed and delivered in connection with the Credit
          Facilities.

     8.14 Recovery of Additional Costs. If the imposition of or any change in
          any law, rule, regulation, or guideline, or the interpretation or
          application of any thereof by any court or administrative or
          governmental authority (including any request or policy not having the
          force of law) shall impose, modify, or make applicable any taxes
          (except federal, state, or local income or franchise taxes imposed on
          the Bank), reserve requirements, capital adequacy requirements, or
          other obligations which would (A) increase the cost to the Bank for
          extending or maintaining the Credit Facilities, (B) reduce the amounts
          payable to the Bank under the Credit Facilities, or (C) reduce the
          rate of return on the Bank's capital as a consequence of the Bank's
          obligations with respect to the Credit Facilities, then the Borrower
          agrees to pay the Bank such additional amounts as will compensate the
          Bank therefor, within five (5) days after the Bank's written demand
          for such payment. The Bank's demand shall be accompanied by an
          explanation of such imposition or charge and a calculation in
          reasonable detail of the additional amounts payable by the Borrower,
          which explanation and calculations shall be conclusive in the absence
          of manifest error.

     8.15 Conflicting Terms. If this agreement is inconsistent with any
          provision in any agreement related to the Credit Facilities, the Bank
          shall determine, in the Bank's sole and absolute discretion, which of
          the provisions shall control any such inconsistency.

     8.16 Expenses. The Borrower agrees to pay or reimburse the Bank for all its
          out-of-pocket costs and expenses and reasonable attorneys' fees
          (including the fees of in-house counsel) incurred in connection with
          the development, preparation and execution of, and in connection with
          the enforcement or preservation of any rights under, this agreement,
          any amendment, supplement, or modification thereto, and any other
          documents prepared in connection herewith or therewith. These costs
          and expenses include without limitation any costs or expenses incurred
          by the Bank in any bankruptcy, reorganization, insolvency or other
          similar proceeding.

9.   WAIVER OF SPECIAL DAMAGES. THE BORROWER WAIVES, TO THE MAXIMUM EXTENT NOT
     PROHIBITED BY LAW, ANY RIGHT THE UNDERSIGNED MAY HAVE TO CLAIM OR RECOVER
     FROM THE BANK IN ANY LEGAL ACTION OR PROCEEDING ANY SPECIAL, EXEMPLARY,
     PUNITIVE OR CONSEQUENTIAL DAMAGES.

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<PAGE>

10.  JURY WAIVER. THE BORROWER AND THE BANK HEREBY VOLUNTARILY, KNOWINGLY,
     IRREVOCABLY AND UNCONDITIONALLY WAIVE ANY RIGHT TO HAVE A JURY PARTICIPATE
     IN RESOLVING ANY DISPUTE WHETHER BASED ON CONTRACT, TORT, OR OTHERWISE)
     BETWEEN THE BORROWER AND THE BANK ARISING OUT OF OR IN ANY WAY RELATED TO
     THIS DOCUMENT. THIS PROVISION IS A MATERIAL INDUCEMENT TO THE BANK TO
     PROVIDE THE FINANCING DESCRIBED HEREIN.

Dated: 5/30, 2002

Address(es) for Notices:           Borrower:

2051 Waukegan Road                 Alltech Associates, Inc.
Deerfield, IL 60015

Attn: GEOFFRY MALTIN               By: /s/ Geoffry Matlin
                                       -----------------------------------------
                                       GEOFFRY MATLIN                      CFO
                                       Printed Name                        Title

                                   Date: 5/20/02

Address for Notices:               Bank:

111 E. Busse Avenue                American National Bank and Trust Company
                                     of Chicago
Mount Prospect, IL 60056

Attn: Thomas A. O'Grady            By: Thomas A. O'Grady
                                       -----------------------------------------
                                       Thomas A. O'Grady    First Vice President
                                       Printed Name                        Title

                                       Date: 5/30/02

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