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                                                                    Exhibit 10.8

                                                          American National Bank
[LOGO]                                              and Trust Company of Chicago

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                    AMENDMENT TO LOAN AND SECURITY AGREEMENT
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     THIS AMENDMENT ("Amendment") is entered into as of this 31st day of May,
2001, by and between Alltech Associates, Inc., an Illinois corporation
("Borrower"), and American National Bank and Trust Company of Chicago ("Bank").

     WHEREAS, Borrower executed in favor of Bank a Loan and Security Agreement
dated July 31, 2000, as amended from time to time, in exchange for Bank's
agreement to lend monies to Borrower (the "Loan Agreement");

     WHEREAS, Borrower executed in favor of Bank various notes from time to
time. Such notes, together with any and all amendments, modifications, renewals
or replacements thereof, are collectively referred to hereinafter as the "Note";

     WHEREAS, the parties hereto desire and have agreed to enter into this
Amendment in order to amend certain terms of the Loan Agreement; and

     NOW, THEREFORE, in consideration of the above recitals, the mutual promises
and agreements of the parties set forth herein and other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree to amend the Loan Agreement as follows:

1. Section 6. WARRANTIES, REPRESENTATIONS AND COVENANTS: GENERAL, Paragraph 6.5
is hereby deleted in its entirety and replaced with the following:

          6.5 Borrower warrants and represents to and covenants with Bank that
     Borrower shall not permit it's "Tangible Capital Funds" (as herein after
     defined) to be less than $3,500,000.00. Tangible Capital Funds shall mean
     stockholders equity less intangible assets including but not limited to
     non-compete agreements, organizational costs, trademarks, patents, and
     goodwill, plus "Subordinated Debt" (as hereinafter defined). Subordinated
     Debt shall mean indebtedness which has been subordinated to the Borrower's
     Liabilities and all other indebtedness of the Borrower to the Bank in
     accordance with a subordination agreement satisfactory to the Bank. The
     definition of stockholder's equity and intangible assets shall be in
     accordance with generally accepted accounting principles.

2. This Amendment shall be incorporated into and made a part of the Loan
Agreement and all other related loan documents executed by Borrower.

3. All terms and provisions of the Loan Agreement and all other related loan
documents between Borrower and Bank, except as expressly modified herein, shall
continue in full force and effect, and Borrower hereby confirms each and every
one of its obligations under the Loan Agreement as amended herein.

4. This Amendment shall be governed by, and construed in accordance with, the
internal laws of the State of Illinois.

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5. This Amendment shall inure to the benefit of Bank's successors and assigns,
and shall be binding upon Borrower's successors and assigns.

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the day and year first written above.

"BORROWER"

Alltech Associates, Inc.
an Illinois corporation

By: /s/ Geoffry F. Matlin
    ----------------------------------
        Geoffry F. Matlin
Its: Chief Fianacial Officer

"BANK"

American National Bank and
Trust Company of Chicago

By: Thomas A. O'Grady
    ----------------------------------
Its: First Vice President

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                                                                    Exhibit 10.9

[LOGO]                                                    American National Bank
                                                    and Trust Company of Chicago

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                           INSTALLMENT NOTE (SECURED)
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$500,000.00                     Chicago, Illinois                August 15, 2000
                                                            Due: August 15, 2005

     FOR VALUE RECEIVED the undersigned (jointly and severally if more than one)
("Borrower"), promises to pay to the order of American National Bank and Trust
Company of Chicago ("Bank"), at its principal place of business in Chicago.
Illinois or such other place as Bank may designate from time to time hereafter,
the principal sum of FIVE HUNDRED THOUSAND AND 00/100 DOLLARS, which sum shall
be due on August 15, 2005, and shall be payable in successive monthly
installments of principal and interest in the aggregate amount of $10,501,31.
The first installment shall be due on the 15th day of September, 2000, and
successive installments shall be paid on the same day of each month, thereafter
until paid.

     Borrower's obligations and liabilities to Bank under this Note, and all
other obligations and liabilities of Borrower to Bank (including without
limitation all debts, claims and indebtedness) whether primary, secondary,
direct, contingent, fixed or otherwise, including those evidenced in rate
hedging agreements designed to protect the Borrower from the fluctuation of
interest rates, heretofore now and/or from time to time hereafter owing, due or
payable, however evidenced, created, incurred, acquired or owing and however
arising, whether under this Note, any agreement, instrument or document
heretofore, now or from time to time hereafter executed and delivered to Bank by
or on behalf of Borrower, or by oral agreement or operation of law or otherwise
shall be defined and referred to herein as "Borrower's Liabilities."

     The unpaid principal balance of Borrower's Liabilities due hereunder shall
bear interest from the date of disbursement until paid, computed at a daily rate
equal to the daily rate equivalent of 9.50% per annum (computed on the basis of
a 360-day year and actual days elapsed), provided, however, that in the event
that any of Borrower's Liabilities are not paid when due, the unpaid amount of
Borrower's Liabilities shall bear interest after the due date until paid at a
rate equal to the sum of the rate that would otherwise be in effect plus 3%.

     Borrower may prepay all or any part of the principal balance of this Note
on one (1) business day's notice provided that, in addition to all principal,
interest and costs owing at the time of prepayment. Borrower pays a prepayment
premium equal to the Current Value of (i) the interest that would have accrued
on the amount prepaid at the interest rate provided in this Note, minus (ii) the
interest that could accrue on the amount prepaid at the Treasury Rate. In both
cases, interest will be calculated from the prepayment date to the maturity
date(s) of the installment(s) being prepaid. Such maturity date(s) shall be
determined by applying the prepayment to the scheduled installment(s) of
principal in their inverse order of maturity. "Treasury Rate" shall mean the
yield, as of the date of prepayment, on United States Treasury bills notes or
bonds, selected by the Bank in its discretion, having maturities comparable to
the scheduled maturities of the installment(s) being prepaid. "Current Value"
means the net present value of the dollar amount of the interest to be earned,
discounted at the Treasury Rate. In no event shall the prepayment premium be
less than zero. Borrower's notice of its intent to prepay shall be irrevocable.
If the balance of this Note is accelerated in accordance with the terms of this
Note, the resulting balance due shall be considered a prepayment due and payable
as of the date of acceleration. Borrower agrees that the prepayment premium is a
reasonable estimate of loss and not a penalty. The prepayment premium is payable
as liquidated damages for the loss of bargain.

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and its payment shall not in any way reduce, affect or impair any other
obligation of Borrower under this Note. In any event, all prepayments shall be
applied to installments of principal in their inverse order of maturity, and no
prepayments shall reduce the dollar amount of fixed principal installments
required to be paid, until this Note is paid in full.

     Borrower warrants and represents to Bank that Borrower shall use the
proceeds represented by this Note solely for proper business purposes and
consistently with all applicable laws and statutes.

     To secure the prompt payment to Bank of Borrower's Liabilities and the
prompt full and faithful performance by Borrower of all of the provisions to be
kept, observed or performed by Borrower under this Note and/or any other
agreement, instrument or document heretofore, now and/or from time to time
hereafter delivered by or on behalf of Borrower to Bank. Borrower grants to Bank
a security interest in and to the following property: (a) all of Borrower's now
existing and/or owned and hereafter arising or acquired monies, reserves,
deposits, deposit accounts and interest or dividends thereon securities, cash,
cash equivalents and other property now or at any time or times hereafter in the
possession or under the control of Bank or its bailee for any purpose; (b) all
business assets of Borrower, pursuant to Loan and Security Agreement dated July
31, 2000, as amended from time to time, by and between Borrower and Bank; and
(c) all substitutions, renewals, improvements, accessions or additions thereto,
replacements, offspring, rents, issues, profits, returns, products and proceeds
thereof, including without limitation proceeds of insurance policies insuring
the foregoing collateral (all of the foregoing property is referred to herein
individually and collectively as "Collateral").

     Regardless of the adequacy of the Collateral, any deposits or other sums at
any time credited by or payable or due from Bank to Borrower, or any monies,
cash, cash equivalents, securities, instruments, documents or other assets of
Borrower in the possession or control of Bank or its Bailee for any purpose, may
be reduced to cash and applied by Bank to or setoff by Bank against Borrower's
Liabilities.

     Borrower agrees to deliver to Bank immediately upon Bank's demand, such
additional collateral as Bank may request from time to time should the value of
the Collateral (in Bank's sole and exclusive opinion) decline, deteriorate,
depreciate or become impaired, or should Bank deem itself insecure for any
reason whatsoever, including without limitation a change in the financial
condition of Borrower or any party liable with respect to Borrower's
Liabilities, and does hereby grant to Bank a continuing security interest in
such other collateral, which shall be deemed to be a part of the Collateral.
Borrower shall execute and deliver to Bank, at any time upon Bank's demand
therefor, all agreements, instruments, documents and other written matter that
Bank may request, in form and substance acceptable to Bank, to perfect and
maintain perfected Bank's security interest in the Collateral or any additional
collateral. Borrower agrees that a carbon, photographic or photostatic copy, or
other reproduction of this Note or of any financing statement, shall be
sufficient as a financing statement.

     Bank may take, and Borrower hereby waives notice of any action from time
to time that Bank may deem necessary or appropriate to maintain or protect the
Collateral, and Bank's security interest therein and in particular Bank may at
any time (i) transfer the whole or any part of the Collateral into the name of
the Bank or its nominee. (ii) collect any amounts due on Collateral directly
from persons obligated thereon. (iii) take control of any proceeds and products
of Collateral, and/or (iv) sue or make any compromise or settlement with respect
to any Collateral. Borrower hereby releases Bank from any and all causes of
action or claims which Borrower may now or hereafter have for any asserted loss
or damage to Borrower claimed to be caused by or arising from: (a) Bank's taking
any action permitted

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by this paragraph; (b) any failure of Bank in protect, enforce or collect in
whole or in part any of the Collateral; and/or (c) any other act or omission to
act on the part of the Bank, its officers, agents or employees, except for
willful misconduct.

     The occurrence of any one of the following events shall constitute a
default by the Borrower ("Event of Default") under this Note :(a) if Borrower
fails to pay any of Borrower's Liabilities when due and payable or declared due
and payable (whether by scheduled maturity, required payment, acceleration,
demand or otherwise); (b) if Borrower or any guarantor of any of Borrower's
Liabilities fails or neglects to perform, keep or observe any term, provision,
condition, covenant, warranty or representation contained in this Note; (c)
occurrence of a default or an event of default under any agreement instrument or
document heretofore, now or at any time hereafter delivered by or on behalf of
Borrower to Bank; (d) occurrence of a default or an event of default under any
agreement, instrument or document heretofore, now or at any time hereafter
delivered to Bank by any guarantor of Borrower's Liabilities or by any person or
entity which has granted to Bank a security interest or lien in and to some or
all of such person's or entity's real or personal property to secure the payment
of Borrower's Liabilities; (e) if the Collateral or any other of Borrower's
assets are attached, seized, subjected to a writ, or are levied upon or become
subject to any lien or come within the possession of any receiver trustee,
custodian or assignee for the benefit of creditors; (f) if a notice of lien levy
or assessment is filed of record or given to Borrower with respect to all or any
of Borrower's assets by any federal, state or local department or agency; (g) if
Borrower or any guarantor of Borrower's Liabilities becomes insolvent or
generally fails to pay or admits in writing its inability to pay debts as they
become due, if a petition under Title 11 of the United States Code or any
similar law or regulation is filed by or against Borrower or any such guarantor,
if Borrower or any such guarantor shall make an assignment for the benefit of
creditors, if any case or proceeding is filed by or against Borrower or any such
guarantor for its dissolution or liquidation, or if Borrower or any such
guarantor is enjoined, restrained or in any way prevented by court order from
conducting all or any material part of its business affairs; (h) the death or
incompetency of Borrower or any guarantor of Borrower's Liabilities, or the
appointment of a conservator for all or any portion of Borrower's assets or the
Collateral; (i) the revocation, termination or cancellation of any guaranty of
Borrower's Liabilities without written consent of Bank; (j) if a contribution
failure occurs with respect to any pension plan maintained by Borrower or any
corporation, trade or business that is, along with Borrower, a member of a
controlled group of corporations or a controlled group of trades or businesses
(as described in Sections 414(b) and (c) of the Internal Revenue Code of 1986 or
Section 4001 of the Employee Retirement Income Security Act of 1974, as amended,
"ERISA") sufficient to give rise to a lien under Section 302(f) of ERISA; (k) if
Borrower or any guarantor of Borrower's Liabilities is in default in the payment
of any obligations, indebtedness or other liabilities to any third party and
such default is declared and is not cured within the time, if any, specified
therefor in any agreement governing the same; (l) if any material statement,
report or certificate made or delivered by Borrower, any of Borrower's partners,
officers, employees or agents or any guarantor of Borrower's Liabilities is not
true and correct; or (m) if Bank is reasonably insecure.

     Upon the occurrence of an Event of Default, at Bank's option, without
notice by Bank to or demand by Bank of Borrower: (i) all of Borrower's
Liabilities shall be immediately due and payable; (ii) Bank may exercise any one
or more of the rights and remedies accruing to a secured party under the Uniform
Commercial Code of the relevant jurisdiction and any other applicable law upon
default by a debtor; (iii) Bank may enter, with or without process of law and
without breach of the peace, any premises where the Collateral is or may be
located, and may seize or remove the Collateral from said premises and/or remain
upon said premises and use the same for the purpose of collecting, preparing and
disposing of the Collateral; and/or (iv) Bank may sell or otherwise dispose of
the Collateral at

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public or private sale for cash or credit provided, however, that Borrower shall
be credited with the net proceeds of any such sale only when the same are
actually received by Bank

     Upon an Event of Default Borrower, immediately upon demand by Bank, shall
assemble the Collateral and make it available to Bank at a place or places to be
designated by Bank which is reasonably convenient to Bank and Borrower

     All of Bank's rights and remedies under this Note are cumulative and
non-exclusive. The acceptance by Bank of any partial payment made hereunder
after the time when any of Borrower's Liabilities become due and payable will
not establish a custom or waive any rights of Bank to enforce prompt payment
hereof. Bank's failure to require strict performance by Borrower of any
provision of this Note shall not waive, affect or diminish any right of Bank
thereafter to demand strict compliance and performance therewith. Any waiver of
an Event of Default hereunder shall not suspend, waive or affect any other Event
of Default hereunder. Borrower and every endorser waive presentment, demand and
protest and notice of presentment, protest, default, non-payment, maturity,
release, compromise, settlement, extension or renewal of this Note, and hereby
ratify and confirm whatever Bank may do in this regard. Borrower further waives
any and all notice or demand to which Borrower might be entitled with respect to
this Note by virtue of any applicable statute or law (to the extent permitted by
law).

     Borrower agrees to pay, immediately upon demand by Bank, any and all costs,
fees and expenses (including reasonable attorneys' fees, costs and expenses)
incurred by Bank (i) in enforcing any of Bank's rights hereunder, and (ii) in
representing Bank in any litigation, contest, suit or dispute, or to commence,
defend or intervene or to take any action with respect to any litigation,
contest, suit or dispute, (whether instituted by Bank, Borrower or any other
person) in any way relating to this Note Borrower's Liabilities or the
Collateral, and to the extent not paid the same shall become part of Borrower's
Liabilities hereunder

     This Note shall be deemed to have been submitted by Borrower to Bank and to
have been made at Bank's principal place of business. This Note shall be
governed and controlled by the internal laws of the State of Illinois and not
the law of conflicts.

     TO INDUCE BANK TO ACCEPT THIS NOTE, BORROWER IRREVOCABLY AGREES THAT,
SUBJECT TO BANK'S SOLE AND ABSOLUTE ELECTION, ALL ACTIONS OR PROCEEDINGS IN ANY
WAY, MANNER OR RESPECT, ARISING OUT OF OR FROM OR RELATED TO THIS NOTE SHALL BE
LITIGATED IN COURTS HAVING SITUS WITHIN THE CITY OF CHICAGO, STATE OF ILLINOIS
BORROWER HEREBY CONSENTS AND SUBMITS TO THE JURISDICTION OF ANY LOCAL, STATE OR
FEDERAL COURT LOCATED WITHIN SAID CITY AND STATE. BORROWER HEREBY WAIVES ANY
RIGHT IT MAY HAVE TO TRANSFER OR CHANGE THE VENUE OF ANY LITIGATION BROUGHT
AGAINST BORROWER BY BANK IN ACCORDANCE WITH THIS PARAGRAPH.

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     BORROWER IRREVOCABLY WAIVES ANY RIGHT TO TRIAL BY JURY IN ANY ACTION, SUIT,
COUNTERCLAIM OR PROCEEDING (I) TO ENFORCE OR DEFEND ANY RIGHTS UNDER OR IN
CONNECTION WITH THIS NOTE OR ANY AMENDMENT, INSTRUMENT DOCUMENT OR AGREEMENT
DELIVERED OR WHICH MAY IN THE FUTURE BE DELIVERED IN CONNECTION HEREWITH, OR
(II) ARISING FROM ANY DISPUTE OR CONTROVERSY IN CONNECTION WITH OR RELATED TO
THIS NOTE OR ANY SUCH AMENDMENT, INSTRUMENT, DOCUMENT OR AGREEMENT, AND AGREES
THAT ANY SUCH ACTION, SUIT, COUNTERCLAIM OR PROCEEDING SHALL BE TRIED BEFORE A
COURT AND NOT BEFORE A JURY.

                                            "BORROWER"

2051 Waukegan Road                          Alltech Associates, Inc.
Bannockburn, Illinois 60015                 an Illinois corporation

FEIN. 36-2696920                            By:  /s/ Richard A. Dolan
                                                --------------------------------
                                                Richard A. Dolan.
                                                Chairman of the Board

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