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                                                                   EXHIBIT 10.27
             
          AMENDED AND RESTATED SCHEDULE TO LOAN AND SECURITY AGREEMENT


CO-BORROWERS: CONSEP, INC., PACOAST INC. AND RICHARD HUNT INC.

ADDRESS:      Consep, Inc. 
              Pacoast, Inc. 
              213 SW Columbia Street 
              Bend, OR 97702

              Richard Hunt, Inc.,
              dba Sierra Ag Chemical
              2749 East Malaga Avenue
              Fresno, CA  93725

DATE:         December 11, 1997



LINE OF CREDIT

CREDIT LIMIT:                      
                      Subject to the reserves stated below, the Credit Limit
                      shall be an amount not to exceed the lesser of: (i)
                      $7,500,000 at any one time outstanding; or (ii) the sum of
                      (a) 70% of the Net Amount of Borrower's accounts, which
                      Silicon in its discretion deems eligible for borrowing,
                      plus (b) 40% of book value of Borrower's eligible
                      inventory, as defined below, as reported to Silicon on a
                      monthly basis, up to a maximum advance against inventory
                      of $1,250,000 outstanding at any one time, plus (c) 100%
                      of the amount of any certificate of deposit owned by
                      Borrower that is in Silicon's possession and in which
                      Silicon has a first priority security interest.
                      Notwithstanding the foregoing, however, (i) the 40%
                      advance rate as stated in clause (b) above shall be
                      increased to 50% for the months of December 1997 through
                      April 1998; and (ii) the $1,250,000 sublimit on inventory
                      advances as stated in clause (b) above shall be increased
                      to $1,500,000 for the months of March 1998 through July
                      1998. The amount otherwise available for borrowing under
                      this line of credit shall be reduced, dollar for dollar,
                      by the face amount of all letters of credit issued by
                      Silicon and by an additional amount of $350,000 with
                      respect to Silicon's day-light overdraft risk associated
                      with Borrower's controlled disbursement accounts. In
                      addition, the outstanding balances of the Secured Term
                      Loan and Secured Term Loan No. 2 described below shall
                      reduce, dollar for dollar, the amount otherwise available
                      for borrowing under the formula stated above at any time
                      during the term hereof during which Borrower fails to
                      comply with the Debt Service Coverage Ratio stated below.
                      There shall be no outstanding advances against inventory
                      during a period of thirty consecutive days each year. "Net
                      Amount" of an account means the gross amount of the
                      account, minus all applicable sales, use, excise and other
                      similar taxes and minus all discounts, credits and
                      allowances of any nature granted or claimed.

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                      Without limiting the fact that the determination of which
                      accounts are eligible for borrowing is a matter of
                      Silicon's discretion, the following will not be deemed
                      eligible for borrowing: accounts that are not subject to a
                      first priority perfected security interest in favor of
                      Silicon, accounts outstanding for more than 90 days from
                      the invoice date, (provided, however, that accounts
                      relating to the following as account debtors are eligible
                      for up to 30 days past their respective due dates provided
                      that such accounts are not outstanding for more than 150
                      days from the invoice date: Cotter & Co., Ace Hardware,
                      Frank's Nursery, Servistar Corp., Commerce/Darbco, US
                      Garden Sales, Agway, Inc., Hardware Wholesalers, Inc., LG
                      Cook Distributors, Central Garden, Caldwell Supply, Arett
                      Sales Corp., J. Mollema & Son, Wetzel Seed Co., and Rite
                      Aid), accounts subject to any contingencies, accounts
                      owing from an account debtor outside the United States
                      (unless pre-approved by Silicon in its discretion, or
                      backed by a letter of credit satisfactory to Silicon, or
                      FCIA insured satisfactory to Silicon), accounts owing from
                      one account debtor to the extent they exceed 25% of the
                      total eligible accounts outstanding, accounts owing from
                      an affiliate of Borrower, and accounts owing from an
                      account debtor to whom Borrower is or may be liable for
                      goods purchased from such account debtor or otherwise. In
                      addition, if more than 50% of the accounts owing from an
                      account debtor are outstanding more than 90 days from the
                      invoice date or are otherwise not eligible accounts, then
                      all accounts owing from that account debtor will be deemed
                      ineligible for borrowing.

                      Without limiting the fact that the determination of which
                      inventory is eligible for borrowing is a matter of
                      Silicon's discretion, the following shall not be deemed
                      eligible for borrowing: any inventory other than packaged
                      chemicals (in boxes, bags, cans or barrels, on which the
                      seal has not been broken) that are owned by Pacoast or
                      Hunt and located in Bend, Oregon or another location
                      identified to Silicon in writing, inventory that is not
                      subject to a first priority perfected security interest in
                      favor of Silicon, inventory that is used, obsolete or
                      returned goods, inventory that is stored at a location
                      other than the Borrower's Address or any location owned,
                      leased or rented by Borrower and previously identified to
                      Silicon, inventory that is subject to a landlord's lien,
                      and inventory that is not in the possession of Borrower.

INTEREST RATE:
                      A rate equal to the "Prime Rate" in effect from time to
                      time, plus 1.50% per annum. Interest shall be calculated
                      on the basis of a 360-day year for the actual number of
                      days elapsed. "Prime Rate" means the rate announced from
                      time to time by Silicon as its "prime rate;" it is a base
                      rate upon which other rates charged by Silicon are based,
                      and it is not necessarily the best rate available at
                      Silicon. The interest rate applicable to the Obligations
                      shall change on each date there is a change in the Prime
                      Rate.

LOAN COMMITMENT
FEE:                  One quarter of one percent per annum of the maximum credit
                      limit of $7,500,000, which was paid at closing.

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MATURITY DATE:        December 10, 1998.


LETTERS OF CREDIT:    Subject to the other terms of the Loan Agreement and the
                      Schedule, Silicon is willing to issue letters of credit on
                      the following terms:


LETTER OF CREDIT
SUBLIMIT:             The amount of all letters of credit, whether commercial or
                      standby letters of credit, outstanding at any one time
                      (including amounts drawn on letters of credit and not yet
                      reimbursed by the Borrower) shall not exceed $1,500,000.00
                      at any one time. The amount of all letters of credit
                      issued by Silicon at the request of the Borrower shall
                      reduce, dollar for dollar, the amount otherwise available
                      to be borrowed under the borrowing base formula described
                      in the first paragraph of this Schedule.

MATURITIES OF
LETTERS OF CREDIT:    Letters of credit issued by Silicon shall have an expiry
                      date of not later than the Maturity Date for the line of
                      credit as stated above. Not later than that date, all
                      letters of credit issued by Silicon shall be satisfied or
                      terminated, with the result that Silicon shall have no
                      continuing obligations under such letters of credit,
                      unless Borrower's obligations to Silicon with respect to
                      such letters of credit is secured by cash pledged to
                      Silicon and in Silicon's possession on terms satisfactory
                      to Silicon, in which case such letters of credit shall
                      have an expiry date of not later than 90 days after the
                      Maturity Date for the line of credit as stated above.

REPAYMENT:            The Borrower shall repay on demand any amount drawn on a
                      letter of credit issued by Silicon. Silicon may, but is
                      not obligated to, add to the principal amount outstanding
                      under the line of credit described above in this Schedule
                      any amount drawn on a letter of credit issued by Silicon.
                      Any such amount shall be subject to the terms applicable
                      to the line of credit described above. For calculating the
                      interest due from the Borrower, no interest shall accrue
                      on the amount of any letters of credit issued by Silicon
                      at the Borrower's request unless Silicon shall actually
                      makes a payment as a result of a draw on any such letter
                      of credit, at which time the amount of the draw shall be
                      deemed an advance on the line of credit described above
                      and shall bear interest accordingly.

ISSUANCE:             The issuance of any letter of credit under this Schedule
                      must be in form and content satisfactory to Silicon and in
                      favor of a beneficiary acceptable to Silicon. The Borrower
                      shall execute Silicon's then-current application forms,
                      reimbursement agreement and related documents as a
                      condition to Silicon's issuance of any letter of credit.

FEES:                 The Borrower shall pay Silicon the fees and costs
                      customarily charged by Silicon (at the time of issuance of
                      the letter of credit) with respect to the issuance of
                      letters of credit.

SECURED TERM LOAN

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CREDIT LIMIT:         An amount not to exceed $215,000 at any one time
                      outstanding. The Borrower shall not be entitled to more
                      than one advance with respect to this Secured Term Loan.
                      The Borrower's indebtedness to Silicon with respect to
                      this Secured Term Loan shall be evidenced by this Schedule
                      and the Loan Agreement, not by a separate promissory note
                      unless required by Silicon. The unpaid principal balance
                      owing on this Secured Term Loan at any time may be
                      evidenced by Silicon's internal records, including daily
                      computer print-outs (which Silicon shall provide to
                      Borrower periodically).

INTEREST RATE:        The interest rate applicable to the Secured Term Loan
                      shall be a rate equal to the "Prime Rate" (as defined
                      above) in effect from time to time, plus 1.5% per annum.
                      Interest calculations shall be made on the basis of a
                      360-day year and the actual number of days elapsed. The
                      interest rate applicable to the Obligations shall change
                      on each date there is a change in the Prime Rate.

AMORTIZATION:         Borrower shall pay Silicon monthly payments of interest on
                      the last day each month commencing with August 1996. In
                      addition, Borrower shall pay Silicon on the last day of
                      each month, commencing with August 1996, the amount
                      necessary to repay fully the amount of the Secured Term
                      Loan in 72 equal monthly payments.

MATURITY DATE:        July 31, 2000, at which time all unpaid principal and
                      accrued but unpaid interest, fees and other charges shall
                      be due and payable.

COMMITMENT
FEE:                  $1,000, which was paid at closing. This fee is fully
                      earned at closing and is non-refundable.

SECURED TERM LOAN NO. 2

CREDIT LIMIT:         An amount not to exceed $250,000 at any one time
                      outstanding. The Borrower shall not be entitled to more
                      than one advance with respect to this Secured Term Loan
                      No. 2. The Borrower's indebtedness to Silicon with respect
                      to this Secured Term Loan No. 2 shall be evidenced by this
                      Schedule and the Loan Agreement, not by a separate
                      promissory note unless required by Silicon. The unpaid
                      principal balance owing on this Secured Term Loan No. 2 at
                      any time may be evidenced by Silicon's internal records,
                      including daily computer print-outs (which Silicon shall
                      provide to Borrower periodically).

INTEREST RATE:        At Borrower's option at the time of disbursement under
                      this Secured Term Loan No. 2, the interest rate applicable
                      to the Secured Term Loan No. 2 shall be a rate equal to
                      the "Prime Rate" (as defined above) in effect from time to
                      time, plus 1.5% per annum, or a two-year fixed rate quoted
                      by Silicon. Interest calculations shall be made on the
                      basis of a 360-day year and the actual number of days
                      elapsed. The interest rate applicable to the Obligations
                      shall change on each date there is a change in the Prime
                      Rate if the variable rate option is chosen by Borrower.

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AMORTIZATION:         Borrower shall pay Silicon monthly payments of interest on
                      the last day each month commencing with July 31, 1997. In
                      addition, Borrower shall pay Silicon on the last day of
                      each month, commencing with July 31, 1997, the amount
                      necessary to repay fully the amount of the Secured Term
                      Loan in 24 equal monthly payments.

MATURITY DATE:        July 31, 1999, at which time all unpaid principal and
                      accrued but unpaid interest, fees and other charges shall
                      be due and payable.

COMMITMENT
FEE:                  $2,500, payable at closing. This fee is fully earned at
                      closing and is non-refundable.

PRIOR NAMES OF
BORROWER:             Consep Membranes, Inc.

TRADE NAMES OF
BORROWER:
                      CheckMate; BioLure; SureFire; Sierra Ag Chemical

OTHER LOCATIONS
AND ADDRESSES:
                      Escalon                      Patterson
                      P.O. Box 335                 P.O. Box 186
                      20001 McHenry Avenue         105 N. 1st Street
                      Escalon, CA 95320            Patterson, CA 95363
                      209-838-2809                 209-892-2601

                      Livingston                   Sacramento
                      P.O. Box 165                 P.O. Box 292337
                      11019 Eucalyptus             8120 37th Avenue
                      Livingston, CA 95334         Sacramento, CA 95824
                      209-394-7981                 916-383-3610

MATERIAL ADVERSE
LITIGATION:           None

NEGATIVE COVENANTS-
EXCEPTIONS:           Without Silicon's prior written consent, Borrower may do
                      the following, provided that, after giving effect thereto,
                      no Event of Default has occurred and no event has occurred
                      which, with notice or passage of time or both, would
                      constitute an Event of Default, and provided that the
                      following are done in compliance with all 


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                      applicable laws, rules and regulations: (i) repurchase
                      shares of Borrower's stock pursuant to any employee stock
                      purchase or benefit plan, provided that the total amount
                      paid by Borrower for such stock does not exceed $200,000
                      in any fiscal year, (ii) incur debt, make loans and incur
                      liability as a guarantor in the ordinary course of
                      business, (iii) pledge up to $350,000 in cash or cash
                      equivalents as collateral for the indebtedness of Chemfree
                      Environment, Inc. (a subsidiary of Borrower) to Royal Bank
                      of Canada; and (iv) make additional advances to Borrower's
                      subsidiaries provided that the total amount of such
                      additional advances shall not exceed $250,000 during the
                      term hereof.

FINANCIAL
COVENANTS:            Borrower shall comply with all of the following covenants
                      on a consolidated basis, except as set forth below.
                      Compliance shall be determined as of the end of each
                      quarter, except as otherwise specifically provided below:

QUICK ASSET RATIO:    Borrower shall maintain a ratio of "Quick Assets" to
                      current liabilities of not less than 0.60:1.00 for the
                      quarter ending December 31, 1997, not less than 0.80:1.00
                      for the quarter ending March 31, 1998, and not less than
                      0.90:1. For the quarter ending June 30, 1998, and
                      thereafter.

TANGIBLE NET WORTH:   Borrower shall maintain a tangible net worth of not less
                      than $12,300,000, plus 50% of the net proceeds of any
                      equity financing of Borrower that closes after the date
                      hereof.


DEBT TO TANGIBLE
NET WORTH RATIO:      Borrower shall maintain a ratio of total liabilities to
                      tangible net worth of not more than 1.25 to 1.0.

PROFITABILITY:        Borrower shall not incur a loss (after taxes) for any
                      fiscal quarter in excess of $1,500,000 for the quarter
                      ending December 31, 1997; a loss in any amount for the
                      quarters ending March 31, 1998 and June 30, 1998; a loss
                      in excess of $250,000 for the quarter ending September 30,
                      1998; a loss in excess of $1,500,000 for the quarter
                      ending December 31, 1998; or a loss for the 1998 fiscal
                      year.

DEBT SERVICE
COVERAGE RATIO:       Borrower shall maintain a Debt Service Coverage Ratio of
                      not less than 1.50:1.00 as of the end of each fiscal
                      quarter of Borrower.

DEFINITIONS:          "Current assets," and "current liabilities" shall have the
                      meanings ascribed to them in accordance with generally
                      accepted accounting principles.

                      "Debt Service Coverage Ratio" means Earnings Before
                      Interest, Taxes, Depreciation and Amortization (EBITDA),
                      divided by the Current Maturities of Long-Term Debt
                      (CMLTD) plus interest. For quarterly calculations,
                      quarterly EBITDA is matched against 25% of CMLTD plus
                      interest.

                      "Tangible net worth" means total shareholders' net worth,
                      determined in 

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                      accordance with generally accepted accounting principles,
                      plus Subordinated Debt (as referred to below), excluding
                      however restricted cash, receivables owing from
                      subsidiaries of Borrower, and all assets which would be
                      classified as intangible assets under generally accepted
                      accounting principles, including without limitation
                      goodwill, licenses, patents, trademarks, trade names,
                      copyrights, capitalized software costs, deferred
                      organizational costs and franchises.

                      "Quick Assets" means cash on hand or on deposit in banks,
                      readily marketable securities issued by the United States,
                      readily marketable commercial paper rated "A-1" by
                      Standard & Poor's Corporation (or a similar rating by a
                      similar rating organization), certificates of deposit and
                      banker's acceptances, and accounts receivable (net of
                      allowance for doubtful accounts).

SUBORDINATED DEBT:    "Liabilities" for purposes of the foregoing covenants do
                      not include indebtedness which is subordinated to the
                      indebtedness to Silicon under a subordination agreement in
                      form specified by Silicon or by language in the instrument
                      evidencing the indebtedness which is acceptable to
                      Silicon.

OTHER COVENANTS       Borrower shall at all times comply with all of the
                      following additional covenants:

                      1. BANKING RELATIONSHIP. Borrower shall at all times
                      maintain its primary banking relationship with Silicon.
                      Borrower shall establish a daily deposit sweep arrangement
                      with either US Bank or First Interstate Bank.

                      2.  FINANCIAL STATEMENTS AND REPORTS. The Borrower shall
                          provide Silicon: (a) within 30 days after the end of
                          each month, a monthly financial statement (consisting
                          of a income statement and a balance sheet) prepared by
                          the Borrower in accordance with generally accepted
                          accounting principles; (b) within 20 days after the
                          end of each month, an accounts receivable aging
                          report, an inventory report and an accounts payable
                          aging report, in such form as Silicon shall reasonably
                          specify; (c) within 20 days after the end of each
                          month, a Borrowing Base Certificate in the form
                          attached to this Agreement as Exhibit A, as Silicon
                          may reasonably modify such Certificate from time to
                          time, signed by the Chief Financial Officer of the
                          Borrower; (d) within 30 days after the end of each
                          quarter, a Compliance Certificate in such form as
                          Silicon shall reasonably specify, signed by the Chief
                          Financial Officer of the Borrower, setting forth
                          calculations showing compliance (at the end of each
                          such calendar quarter) with the financial covenants
                          set forth on the Schedule, and certifying that
                          throughout such quarter the Borrower was in full
                          compliance with all other terms and conditions of this
                          Agreement and the Schedule, and providing such other
                          information as Silicon shall reasonably request; (e)
                          within five days after filing, all 10Q and 10K reports
                          and other reports filed with the Securities Exchange
                          Commission; and (f) within 90 days following the end
                          of the Borrower's fiscal year, complete annual
                          CPA-audited financial statements, such audit being
                          conducted by independent certified public accountants
                          reasonably acceptable to Silicon, together with an
                          unqualified opinion of such accountants.

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                      3. INDEBTEDNESS. Without limiting any of the foregoing
                      terms or provisions of this Agreement, Borrower shall not
                      in the future incur indebtedness for borrowed money,
                      except for (i) indebtedness to Silicon, and (ii)
                      indebtedness incurred in the future for the purchase price
                      of or lease of equipment in an aggregate amount not
                      exceeding normal course of business at any time
                      outstanding.

                             BORROWER:
                                                   CONSEP, INC.

                                                   BY: /s/ Larry Katz
                                                       -------------------------
                                                   ITS: Chief Financial Officer
                                                       -------------------------
                                                   PACOAST INC.

                                                   BY: /s/ Volker Oakey
                                                       -------------------------
                                                   ITS: Vice President
                                                       -------------------------

                                                   RICHARD HUNT INC.

                                                   BY: /s/ Volker Oakey
                                                       -------------------------
                                                   ITS: President
                                                       -------------------------

                             SILICON:
                                                   SILICON VALLEY BANK

                                                   BY: /s/ Ron Sherman
                                                       -------------------------
                                                   ITS: Vice President
                                                       -------------------------

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                                    EXHIBIT A


                       [INSERT BORROWING BASE CERTIFICATE]





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