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                                                                   Exhibit 10.50


                                MULTIPLE ADVANCE
                               NON-REVOLVING NOTE


            FOR VALUE RECEIVED, Bionutrics, Inc., a Nevada corporation
("Borrower"), hereby promises to pay to the order of William McCormick, as agent
("Agent"), for the ratable benefit of Ropart Investments, LLC, Xiagen Ltd.,
William McCormick, Ronald H. Lane and Fred Rentschler (collectively, "Lenders"),
at the office of Agent located at 660 Steamboat Road, Greenwich, CT 06830 or at
such other place as Agent may designate, on January 1, 2002, or earlier as
required herein, the sum of Six Hundred Thousand Dollars ($600,000.00) or such
lesser sum as from time to time shall be outstanding hereunder, as reflected in
the books and records of Agent, such sum to include the Accreted Interest
(defined below), and, to the extent applicable, shall pay the Default Interest
Rate specified below, in accordance with the following terms and conditions:

            1. BACKGROUND. Pursuant to the Loan and Stock Pledge Agreement, of
even date herewith, executed by Borrower, Lenders and Agent (the "Loan
Agreement"), Lenders have agreed to, jointly and severally, make a multiple
advance loan to Borrower in an amount not to exceed Five Hundred Thousand
Dollars ($500,000.00) (the "Loan"). This Note is executed pursuant to the Loan
Agreement. Borrower's obligations under the Loan are secured by the collateral
described in the Loan Agreement. The Loan Agreement contains additional terms
relating to the Loan.

            2. CONTRACTED FOR RATE OF INTEREST. The contracted for rate of
interest of the indebtedness evidenced hereby, without limitation, shall consist
of the following:

                  (a) The Accreted Interest, which shall be equal to the
original issue discount between the date of issuance and the date of payment
based on the advances made under this Note from time to time outstanding such
that the Accreted Interest shall be equal to $100,000 if the full $500,000 is
advanced pursuant to the Loan;

                  (b) The Default Interest Rate (as hereinafter defined), as
from time to time in effect, calculated daily on the basis of actual days
elapsed over a 365-day year, applied to the principal balance from time to time
outstanding hereunder; and

                  (c)   All Additional Sums (as hereinafter defined), if any.

Borrower agrees to pay an effective contracted for rate of interest which is the
sum of the Accreted Interest referred to in subsection 2(a) above, plus any
additional rate of interest resulting from the application of the Default
Interest Rate referred to in subsection 2(b) above, and the Additional Sums, if
any, referred to in subsection 2(c) above.
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            3. DEFAULT INTEREST RATE. The Default Interest Rate shall be a per
annum rate equal to 25%. The principal balance outstanding hereunder from time
to time shall bear interest at the Default Interest Rate from the date of the
occurrence of an Event of Default (as hereinafter defined) until the earlier of:
(a) the date on which the principal balance outstanding hereunder, together with
all Accreted Interest and other amounts payable hereunder, are paid in full; or
(b) the date on which such Event of Default is timely cured in a manner
satisfactory to Agent. The Default Interest Rate shall be payable on the fifth
(5th) day of each month.

            4. PRINCIPAL BALANCE. The principal balance outstanding hereunder at
any time shall be the total amount of advances made hereunder by Lenders less
the total amount of payments of principal hereon as reflected in the books and
records of Agent with respect to the indebtedness evidenced hereby.

            5. AGGREGATE OF ADVANCES. Borrower and Lenders contemplate a series
of obligatory advances from time to time hereunder, even if the principal
balance outstanding hereunder has previously been reduced to zero; provided,
however, such advances in the aggregate shall not exceed the principal amount
first set forth above. Lenders shall be required to make any advance requested
by Borrower in accordance with this Note as long as no Event of Default exists
on the date of such request. Such advances shall be on a non-revolving basis and
any reduction in the principal balance outstanding hereunder shall not entitle
Borrower to any additional advance to the extent such additional advance in the
aggregate with all prior advances hereunder would exceed the principal amount
first set forth above.

            6. REQUESTS FOR ADVANCES AND DISBURSEMENT OF ADVANCES. When Borrower
desires an advance under the Loan, Borrower shall make a written request to
Agent for such an advance. Such request shall specify the amount of the advance
and the date of disbursement. Agent shall immediately communicate Borrower's
request to each of Lenders and Lenders shall make available to the Agent the
appropriate amount of funds to satisfy the disbursement request of Borrower.
Agent shall remit the appropriate amounts to Borrower on the date requested by
Borrower.

            7. PAYMENT. This Note shall be payable in full on the earlier of (i)
January 1, 2002; (ii) the funding of any loan or loans in cumulative amounts in
excess of two million dollars; or (iii) the issuance by the Borrower of any
common stock or preferred stock in cumulative amounts in excess of one million
dollars. Payments received by Agent with respect to the indebtedness enclosed
hereby shall be applied in such order and manner as Agent in his sole and
absolute discretion may elect. Payments hereunder shall be made at the address
for Agent first set forth above, or at such other address as Agent may specify
to Borrower in writing.

            8. PREPAYMENTS. Payments may be made at any time, or from time to
time, in whole or in part, without penalty, together with all previously matured
Accreted Interest and other charges accrued to the date of prepayment.
Notwithstanding any prepayment hereof: (a)


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there will be no change in the due date or amount of scheduled payments due
hereunder unless Lenders unanimously agree in writing to such change; and (b)
Borrower's obligations hereunder shall continue in effect and this Note shall
remain outstanding, unless and until (i) the principal balance outstanding
hereunder, together with all Accreted Interest and other amounts payable
hereunder or in any of the Loan Documents, are paid in full, and (ii)
thereafter, upon Borrower's request, Agent delivers to Borrower the original
executed copy of this Note marked "cancelled."

            9. EVENTS OF DEFAULT; ACCELERATION. The occurrence of any one or
more of the following events shall constitute an "Event of Default" hereunder,
and upon such Event of Default, the entire principal balance outstanding
hereunder, together with all Accreted Interest and other amounts payable
hereunder, at the election of Agent, shall become immediately due and payable,
without any notice to Borrower:

                  (a) Nonpayment of principal, interest or any other amounts
when the same shall become due and payable hereunder;

                  (b) The failure of Borrower to comply with any provision of
this Note, the Loan Agreement or any of the other documents executed in
connection with the transaction contemplated by the Loan Agreement
(collectively, the "Loan Documents"); or

                  (c) The appointment of (or application for appointment of) a
receiver of Borrower or any other person or entity who is or may become liable
hereunder, or the involuntary filing against or voluntary filing by Borrower, or
any other person or entity who is or may become liable hereunder, of a petition
or application for relief under federal bankruptcy law or any similar state or
federal law, or the issuance of any writ of garnishment, execution or attachment
for service with respect to Borrower or any person or entity who is or may
become liable hereunder, or any property of Borrower or property of any person
or entity who is or may become liable hereunder.

            10. ADDITIONAL SUMS. All fees, charges, goods, things in action or
any other sums or things of value, other than the interest resulting from the
Accreted Interest and the Default Interest Rate, as applicable, paid or payable
by Borrower (collectively, the "Additional Sums"), whether pursuant to this
Note, the Loan Documents or any other document or instrument in any way
pertaining to this lending transaction, or otherwise with respect to this
lending transaction, that, under the laws of the State of Arizona, may be deemed
to be interest with respect to this lending transaction, for the purpose of any
laws of the State of Arizona that may limit the maximum amount of interest to be
charged with respect to this lending transaction, shall be payable by Borrower
as, and shall be deemed to be, additional interest, and for such purposes only,
the agreed upon and "contracted for rate of interest" of this lending
transaction shall be deemed to be increased by the rate of interest resulting
from the Additional Sums. Borrower understands and believes that this lending
transaction complies with the usury laws of the State of Arizona; however, if
any interest or other charges in connection with this lending transaction are
ever determined to exceed the maximum amount permitted by law, then Borrower


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agrees that: (a) the amount of interest or charges payable pursuant to this
lending transaction shall be reduced to the maximum amount permitted by law; and
(b) any excess amount previously collected from Borrower in connection with this
lending transaction that exceeded the maximum amount permitted by law, will be
credited against the principal balance then outstanding hereunder. If the
outstanding principal balance hereunder has been paid in full, the excess amount
paid will be refunded to Borrower.

            11. WAIVERS. Except as set forth in this Note or the Loan Documents,
to the extent permitted by applicable law, Borrower, and each person who is or
may become liable hereunder, severally waive and agree not to assert: (a) any
homestead or exemption rights; (b) demand, diligence, grace, presentment for
payment, protest, notice of nonpayment, nonperformance, extension, dishonor,
maturity, protest and default; and (c) recourse to guaranty or suretyship
defenses (including, without limitation, the right to require Lenders to bring
an action on this Note). Lenders may, if they unanimously agree, extend the time
for payment of or renew this Note, release collateral as security for the
indebtedness evidenced hereby, or release any party from liability hereunder,
and any such extension, renewal, release or other indulgence shall not alter or
diminish the liability of Borrower or any other person or entity who is or may
become liable on this Note except to the extent expressly set forth in a writing
evidencing or constituting such extension, renewal, release or other indulgence.

            12. COLLECTION COSTS AND EXPENSES. Borrower agrees to pay all costs
of collection, including, without limitation, attorneys' fees, whether or not
suit is filed, and all costs of suit and preparation for suit (whether at trial
or appellate level), in the event any payment of principal, interest or other
amount under the Loan is not paid when due, or in the event it becomes necessary
to protect the Pledged Collateral (as defined in the Loan Agreement), or to
exercise any other right or remedy under this Note, the Loan Agreement or in the
Loan Documents, or in the event Agent or Lenders are made parties to any
litigation because of the existence of this Note, the Loan Agreement or the
other Loan Documents or if at any time Lenders should incur any attorneys' fees
in any proceeding under any federal bankruptcy law (or any similar state or
federal law) in connection with this Note, the Loan Agreement or the other Loan
Documents. In the event of any court proceeding, attorneys' fees shall be set by
the court and not by the jury and shall be included in any judgment obtained by
Agent or Lenders, as applicable.

            13. NO WAIVER BY LENDERS. No delay or failure of Lenders in
exercising any right hereunder shall affect such right, nor shall any single or
partial exercise of any right preclude further exercise thereof.

            14. GOVERNING LAW. This Note shall be governed by and construed and
interpreted in accordance with the laws of the State of Arizona, notwithstanding
any Arizona or other conflict-of-laws provision to the contrary.


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            15. JURISDICTION AND VENUE. Borrower and Lenders hereby expressly
agree that in the event any actions or other legal proceedings are initiated by
or against Borrower, Agent or Lenders involving any alleged breach or failure by
any party to pay, perform or observe any sums, obligations or covenants to be
paid, performed or observed by it under this Note, the Loan Agreement or the
other Loan Documents, or involving any other claims or allegations arising out
of the transactions evidenced or contemplated by this Note, the Loan Agreement
or the other Loan Documents, regardless of whether such actions or proceedings
shall be for damages, specific performance or declaratory relief or otherwise,
such actions shall be brought in Maricopa County, Arizona, and Borrower and
Lenders hereby submit to the jurisdiction of the State of Arizona for such
purposes and agrees that the venue of such actions or proceedings shall properly
lie in Maricopa County, Arizona.

            16. TIME OF ESSENCE. Time is of the essence of this Note and each
and every provision hereof.

            17. AMENDMENTS. No amendment, modification, change, waiver, release
or discharge hereof and hereunder shall be effective unless evidenced by an
instrument in writing and signed by the party against whom enforcement is
sought.

            18. PROVISIONS SEVERABLE. The provisions of this Note are
independent of and severable from each other, and no provision shall be affected
or rendered invalid or unenforceable by virtue of the fact that for any reason
any other or others of them may be invalid or unenforceable in whole or in part.
Further, if a court of competent jurisdiction determines that any provision of
this Note is invalid or unenforceable as written, the court may interpret,
construe, rewrite or revise such provision, to the fullest extent allowed by
law, so as to make it valid and enforceable consistent with the intent of the
parties.

            19. BINDING NATURE. The provisions of this Note shall be binding
upon Borrower and the heirs, personal representatives, successors and assigns of
Borrower, and shall inure to the benefit of Lenders and any subsequent holder of
all or any portion of this Note, and their respective successors and assigns.

            20. NOTICE. Any notice or other communication with respect to this
Note shall: (a) be in writing; (b) be effective on the day of hand-delivery
thereof to the party to whom directed, one day following the day of deposit
thereof with delivery charges prepaid with a national overnight delivery
service, or two days following the day of deposit thereof with postage prepaid
with the United States Postal Service, by regular first class, certified or
registered mail; (c) if directed to Agent, be addressed to Agent at the address
of Agent first set forth above or to such other address as Agent shall have
specified by like notice; (d) if directed to Borrower, be addressed to Borrower
at the address for Borrower set forth below Borrower's name, or to such other
address as Borrower shall have specified by like notice; and (e) if directed to
one of Lenders, be addressed to Lender at the address for that Lender set forth
below Lender's name, or to such other address as Lender shall have specified by
like notice.


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            21. SECTION HEADINGS. The section headings set forth in this Note
are for convenience only and shall not have substantive meaning hereunder or be
deemed part of this Note.

            22. CONSTRUCTION. This Note shall be construed as a whole in
accordance with its fair meaning and without regard to or taking into account
any presumption or other rule of law requiring construction against the party
preparing this Note.

            IN WITNESS WHEREOF, Borrower has executed this Note as of
June 20, 2001
                                    "BORROWER"

                                    BIONUTRICS, INC., a Nevada corporation

                                    By:  /s/Ronald H. Lane
                                        _______________________________________
                                    Name:  Ronald H. Lane
                                    Title:  President


                                    Address of Borrower:

                                    2425 East Camelback Road
                                    Suite 650
                                    Phoenix, Arizona  85016
                                    Attention: ________________________________



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                           ACKNOWLEDGEMENT OF LENDERS

            The Lenders hereby agree to be bound by the terms of this Note.

                                    "LENDERS"

                                    /s/William McCormick
                                    -------------------------------------
                                    Name: William McCormick

                                    Address of William McCormick:
                                    c/o Inverness
                                     660 Steamboat Road
                                     Greenwich, CT  06830


                                    /s/ William McCormick
                                    -------------------------------------
                                    Name:  Xiagen, Ltd.

                                    Address of Xiagen Ltd.:
                                    c/o Inverness
                                    660 Steamboat Road
                                     Greenwich, CT  06830


                                    /s/Robert B. Goergen
                                    -------------------------------------
                                    Name: Ropart Investments, LLC

                                    Address of Ropart Investments, LLC:
                                    One East Weaver Street
                                    Greenwich, CT  06831


                                    /s/ Frederick B. Rentschler
                                    -------------------------------------
                                    Name:  Frederick B. Rentschler

                                    Address of Frederick B. Rentsher:
                                    P.O. Box 4710
                                    Cave Creek, AZ  85327
                                    ------------------------


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                                    /s/ Ronald H. Lane
                                    -------------------------------------
                                    Name:  Ronald H. Lane

                                    Address of Ronald H. Lane:
                                    2425 E. Camelback Road
                                    Suite 650
                                    Phoenix, AZ  85016



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