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                                                                   EXHIBIT 10.42

                                                          [Logo] Basler
                                                                 Kantonalbank
                                                          GARANTIERT SICHER

                                                          Discovery Technologies
                                                          Attn. Dr. H. Zinsli
                                                          Gewerbestrasse 16
                                                          4123 Allschwil


December 22, 1999 K10/TRU
Thomas Ruedin
061 266 27 91

Dear Dr. Zinsli

Following our various discussions we herewith confirm the establishment of a new
credit line which will replace all previous credit agreements between Discovery
Technologies Ltd. and Basler Kantonalbank:

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BORROWER          Discovery Technologies Ltd., Gewerbestrasse 16, 4123
                  Allschwil, the "Borrower"

LENDER            Basler Kantonalbank, Spiegelgasse 2, 4002 Basel, the "Lender"
                  or "BKB"

AMOUNT            CHF 2'000'000.-- (two million Swiss Francs)

DURATION          until further notice, i.e. under the condition that the
                  pledged assets placed with BKB by the Borrower amount to at
                  least CHF 2'000'000.-- (see section "collateral").

UTILIZATION       The Credit Line can be utilized up to a maximum amount of CHF
                  2'000'000.-- on a Current Account basis - as Fixed Term
                  Advances with minimum amounts of CHF 500'000.-- and durations
                  of 3 months up to 12 months

INTEREST RATES    Current Account CHF

                  currently 4.75% per annum, variable + 0.25% per quarter
                  commission on average utilized amount

                  The Lender has the right to change the interest rate at any
                  time in case of changes of the market situation.

                  The interest is payable quarterly in arrear, as per March 31,
                  June 30,
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                                                            [Logo]  Basler
                                                                    Kantonalbank
                                                            GARANTIERT SICHER

Discovery Technologies Ltd.          Seite 2                            22.12.99
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                  September 30 and December 31.

                  Fixed Term Advances

                  Interest rates for Fixed Term Advances will be fixed two
                  banking days prior to the drawdown of the advance based on the
                  LIBOR for the respective duration plus a margin of 0.75% per
                  annum.

                  Interest is payable at maturity of each advance if the
                  duration of the advance does not exceed six months. Interest
                  is payable semi-annually for durations of advances of more
                  than six months. Interest shall be calculated on the basis of
                  the actual number of days elapsed and a 360-days-year.

COLLATERAL        - Pledge of cash accounts and/or time deposits placed with BKB
                    by the Borrower with a value of at least CHF 2'000'000.--
                    (as per enclosed form "Allgemeine Pfandbestellung")

                  - Pledge of Accounts Receivables (as per enclosed form
                    "Generelle Forderungsabtretung")

TERMINATION       This Credit Facility is non-cancelable by the Borrower and the
                  Lender until December 31, 2000. However, an early termination
                  by the Lender is possible a) in case of default through
                  overdue interest or commission payments by the Borrower with
                  more than 30 days or b) if the value of pledged cash accounts
                  and/or time deposits placed with BKB by the Borrower is less
                  than CHF 2'000'000.-- or c) according to the General
                  Conditions of BKB

                  In case of an early termination by the Lender Fixed Term
                  Advances become due at once.

MISCELLANEOUS     During the life time of this Credit Line the Borrower shall
                  provide the Lender with audited annual and unaudited quarterly
                  balance sheets and profit and loss accounts as soon as they
                  become available but not later than 3 months after the
                  respective year end and 1 month after the respective end of
                  the quarter.

                  The enclosed "General Conditions" of Basler Kantonalbank form
                  an integral part of this agreement.

                  This Credit Line will be operative after signing will replace
                  all existing credit agreements between Borrower and Lender.

GOVERNING LAW     The present contract is GOVERNED BY SWISS LAW. Any disputes
                  shall fall within the jurisdiction of the COURT OF THE CANTON
                  BASAL-CITY.
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                                                            [Logo]  Basler
                                                                    Kantonalbank
                                                            GARANTIERT SICHER

Discovery Technologies Ltd.          Seite 3                            22.12.99
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                  It is expressively agreed upon that the Lender shall also be
                  entitled to enforce its rights and to take legal action
                  against the Borrower in other Courts or any other jurisdiction
                  the Lender deems necessary, in which event, Swiss law shall
                  remain applicable.
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Please confirm your consent by signing and returning to us the enclosed

      -  Copy of this Credit Agreement

      -  Form "Allgemeine Pfandbestellung"

      -  Form "Generelle Forderungsabtretung"

as soon as possible but not later than December 30, 1999.

Thank you very much for your confidence. We are looking forward to a pleasant
continuation of the business relationship with your company.

                                          Yours sincerely,

                                          BASLER KANTONALBANK


                                          /s/ Kurt H. Hercher  /s/ Thomas Ruedin
                                          -------------------  -----------------
                                          Kurt H. Hercher      Thomas Ruedin

Enclosure

Agreed and Accepted:

Discovery Technologies Ltd.:      /s/ illegible         /s/ illegible
                                  ---------------------------------------
Date/Place     Jan 10, 2000
               ----------------------------------------------------------


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                                                            [Logo] Basler
                                                                   Kantonalbank
                                                            GARANTIERT SICHER


GENERAL BUSINESS CONDITIONS
Edition 1984


1.    PURPOSES AND SCOPE

      Under reserve of special arrangements, the general conditions set forth
      herein govern the business relationship between the customer and the Bank.
      In addition, separate regulations of the Bank and relevant customs and
      usages apply to particular kinds of business.

2.    AUTHORIZED SIGNATURES

      The list of signatures of persons authorized to sign for the customer,
      which has been deposited with the Bank, shall be effective for its
      purposes until written notice of a change shall have been received by the
      Bank, notwithstanding any entries in the Commercial Register for
      publications with contrary effect. A deposit account and/or custody
      account may be opened by several persons. In the absence of contrary
      arrangements, the entitled persons may only jointly dispose of any
      deposits with the Bank.

3.    CUSTOMER'S COMPLAINTS, DELAYS

      Customer's complaints referring to the carrying out of instructions given
      to the Bank must be lodged immediately to facilitate a prompt inquiry; the
      same also applies to objections concerning statements of deposit accounts
      and custody accounts and to other communications or advices. Losses
      resulting from a delay in making a complaint shall be borne by the
      customer.

      In case of delay in carrying out payment transactions, the Bank shall be
      liable solely for payment of interest for the period involved, except in
      cases where its attention has been specifically directed to the danger of
      particular damage.

4.    EXAMINATION OF SIGNATURES AND LAWFUL ENTITLEMENT

      Losses resulting from failure by the Bank to discover forgeries or defects
      with respect to identification shall be borne by the customer unless the
      Bank is guilty of gross negligence.

5.    INCAPACITY TO ACT

      The customer shall bear losses arising from his own incapacity to act or
      the incapacity of third persons unless the fact of his incapacity has been
      published in the KANTONALBANK BASAL-STADT as well as if the incapacity to
      act of his authorized agents and third persons has been notified to the
      Bank in writing.

6.    ERRORS IN TRANSMISSION

      The Bank shall not be responsible for damages arising from the use of the
      postal, telegraph, telephone or telex services or other systems of
      communication, in particular as a result of misunderstandings, loss,
      delay, mutilations or duplications, except where the Bank is guilty of
      gross negligence.

7.    COMMUNICATIONS

      All communications by the Bank shall be deemed to have been validly made
      if sent to the last address given by the customer or otherwise held at his
      disposal in accordance with his instructions.

      The date of the copies or mailing lists in the possession of the Bank
      shall be deemed to be the date of dispatch.

8.    LIEN AND SET-OFF

      The Bank shall have a lien as to all assets which are held at any time for
      the customer at its offices or elsewhere and shall be entitled to set off
      against each other the balances of all accounts of the customer in
      satisfaction of all claims irrespective of the due date and currency
      involved.

      This shall also apply to credits and loans whether or not they are secured
      by specific collateral. In the event of default by the customer, the Bank
      shall be entitled at its discretion to realize the assets by court order
      or in whatever manner it chooses.

9.    CURRENT ACCOUNT TRANSACTIONS

      The usual interest rates or those fixed by the Bank, delay interest since
      the last maturity, commissions, as well as charges, expenses and taxes,
      etc. are credited or debited at the Bank's choice on a quarterly,
      semi-annual or annual basis unless otherwise arranged with the customer.

      The Bank shall be entitled to adjust its interest and commission rates at
      any time, particularly in conformity with charges in money market
      conditions; the customer shall be notified thereof by circular or in any
      other appropriate manner.

      Statements of account which are sent to the customer by the Bank and to
      which no objection has been raised within one month, shall be deemed to
      have been accepted by the customer even if a signed reconciliation
      statement has not been received by the Bank. The explicit or implied
      approval of a statement of account shall be deemed also to include all
      items entered therein and all reservations made by the Bank.

10.   FOREIGN CURRENCY ACCOUNTS

      The assets of the Bank relative to customer's accounts in foreign
      currencies shall be held in the name of the Bank, but for the account and
      risk of the customer, with correspondents considered by the Bank as
      appropriate, inside or outside the currency area in question. The risk of
      legal or governmental restrictions and charges shall be borne by the
      customer.

      The customer is entitled to dispose of foreign currency credit balances by
      selling, drawing a cheque on his own account or buying a banker's cheque
      (cashier's cheque) for debit to his account and by ordering transfers;
      other disposals require the consent of the Bank.

11.   CREDITING OF SUMS IN FOREIGN CURRENCY

      Sums received in foreign currencies shall be credited in Swiss francs at
      the rate of exchange obtained on the day in question unless the customer
      has given instructions to the contrary or has an account in the
      corresponding foreign currency. If the customer's accounts are only in
      currencies other than Swiss francs, the Bank may credit the sum in one of
      these currencies.

12.   REDEBITING OF CHEQUES, DRAFTS, ETC.

      If drafts, cheques and other instruments received for collection or
      discounted, are not paid, or if the proceeds thereof cannot be freely
      disposed of, the Bank shall be entitled to cancel credit advices; all
      claims against any liable person, arising from these instruments, remain
      nevertheless with the Bank until the payment of all indebtedness.

13.   TERMINATION OF A BUSINESS RELATIONSHIP

      The Bank reserves the right to terminate business relationships at
      anytime, especially to cancel agreed upon or granted credit facilities and
      to demand immediate payment of its claims without further notice. This
      applies also to credit facilities and loans with fixed maturities or
      cancellation periods, provided the economic situation of the customer, as
      judged by the Bank, no longer justifies a continuation of existing
      business deals.

14.   HOLIDAYS

      In all business relationships with the Bank, Saturday shall be treated as
      a public holiday.

15.   CHANGES OF GENERAL BUSINESS CONDITIONS

      The Bank reserves the right to change the general business conditions.
      Customers shall be notified of such changes by circular or in another
      appropriate manner. The Bank considers the new conditions as accepted by
      the customer if no notice to the contrary is received within one month.

16.   APPLICABLE LAW, JURISDICTION, PLACE OF PERFORMANCE AND FOR DEBT COLLECTION
      PROCEEDINGS

      All the legal relationships between the customer and the Bank shall be
      governed by Swiss law.

      The place of performance, and in the case of customers domiciled abroad,
      also the place for special proceedings for the collection of debts shall
      be the Bank's place of business in Basel.

      In the case of litigation the courts of Basel City shall have exclusive
      jurisdiction.

      The Bank is also entitled to bring proceedings against the customer at the
      competent court in his domicile or in any other competent jurisdiction.

The german version is decisive in case of differences that may occur in the
interpretation of the german and english version of this document.

                                                             BASLER KANTONALBANK


Basel. lst July 1984