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                                                                   Exhibit 10.51


                         LOAN AND STOCK PLEDGE AGREEMENT

            THIS LOAN AND STOCK PLEDGE AGREEMENT (this "Agreement") is made and
entered into as of the 20th day of June, 2001, by and among Bionutrics, Inc., a
Nevada corporation ("Borrower"), Ropart Investments, LLC, Xiagen Ltd., William
McCormick, Ronald H. Lane and Fred Rentschler (collectively, "Lenders"), and
William McCormick, as agent for Lenders ("Agent").

                                    RECITALS

            A. Borrower has requested, and Lenders have jointly and severally
agreed that Lenders make a multiple advance loan to Borrower in an amount not to
exceed Five Hundred Thousand Dollars ($500,000.00) (the "Loan").

            B. Lenders have requested, and Agent has agreed, that Agent act as
their agent for purposes of administering the Loan and holding the collateral
for the Loan.

                                    AGREEMENT

            NOW, THEREFORE, in consideration of the premises and of the mutual
covenants set forth in this Agreement, the parties hereby agree as follows:

            1. LOAN. Lenders hereby jointly and severally agree to make the Loan
to Borrower. Borrower shall execute the Multiple Advance Non-Revolving Note, of
even date herewith, in the maximum principal amount of Five Hundred Thousand
Dollars ($500,000.00) in favor of Agent, for the ratable benefit of Lenders (the
"Note").

            2. AGENT.

                  (a) APPOINTMENT OF AGENT. Lenders hereby irrevocably designate
and appoint Agent as the agent of Lenders for purposes of administering the Loan
and holding any collateral for the Loan. Lenders irrevocably authorize Agent to
take such action on their behalf with respect to the Loan and any collateral for
the Loan and to exercise such powers and perform such duties as are reasonably
incidental thereto.

                  (b) EXCULPATORY PROVISIONS. Agent shall not have (i) any
duties or responsibilities, except those expressly set forth herein or in the
Note, or (ii) any fiduciary relationship with any of Lenders. No implied
covenants, functions, responsibilities, duties, obligations or liabilities shall
be read into this Agreement, the Note or the other Loan Documents (as defined in
the Note) or otherwise exist against Agent. Agent shall not be (i) liable to
Lenders for any action lawfully taken or not taken by it under or in connection
with the Loan, or (ii) responsible in any manner to any of Lenders for (x) any
recitals, statements, representations or warranties made by Borrower under or in
connection with the Loan Documents, (y) the value,
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validity, effectiveness, genuineness, enforceability or sufficiency of the Note,
this Agreement or any other Loan Document, or (z) any failure of Borrower to
perform its obligations hereunder or thereunder.

                  (c) SUCCESSOR AGENT. Agent may resign upon thirty (30) days'
prior written notice to Borrower and Lenders. If Agent resigns as Agent, then
Lenders during such thirty (30) day period shall appoint a successor agent, the
selection of which they shall unanimously agree upon. Such successor agent shall
succeed to the rights, powers and duties of Agent and the term "Agent" shall
mean such successor agent, effective upon its appointment. The former Agent's
rights, powers and duties as Agent shall be terminated, without any other or
further act or deed on the part of such former Agent, Borrower or Lenders.
Notwithstanding anything herein to the contrary, so long as no Event of Default
(as defined in the Note) shall have occurred and be continuing, the appointment
of each successor Agent shall be subject to the prior approval by Borrower.

            3. PLEDGE OF STOCK. Borrower hereby pledges to Agent, for the
ratable benefit of Lenders, and grants to Agent, for the ratable benefit of
Lenders, a security interest in, all right, title and interest (legal and
equitable) of Borrower in one hundred (100) shares of common stock, par value
$.01 per share, of InCon Technologies, Inc., a Delaware corporation, represented
by stock certificate No. 1 in the name of Nutrition Technology Corporation, a
wholly-owned subsidiary of Borrower (the "Pledged Shares") and all cash,
instruments and other property or proceeds from time to time received,
receivable or otherwise distributed in respect or in exchange for any or all of
the Pledged Shares (collectively, the "Pledged Collateral").

            4. SECURITY FOR OBLIGATIONS. This Agreement secures, and the Pledged
Collateral is security for, the full, complete and timely payment, performance
and discharge of Borrower's obligations under the Note, this Agreement and the
Loan Documents.

            5. DELIVERY OF PLEDGED COLLATERAL. Borrower shall deliver to Agent
all certificates representing or evidencing the Pledged Shares and such
certificates shall be accompanied by duly executed instruments of transfer or
assignment in blank, in form and content substantially similar to Exhibit A as
attached hereto.

            6. JOINT AND SEVERAL OBLIGATIONS; RIGHT OF CONTRIBUTION. It is the
intention of Lenders that the advances under the Loan to Borrower shall be made
on a pro rata basis by each of Lenders providing its pro rata share of the
requested advance to Agent to be disbursed by Agent to Borrower. Notwithstanding
the foregoing, the obligations of Lenders to make the Loan to Borrower are joint
and several obligations of each of Lenders. If one or more Lenders fail to make
such advances according to the terms of the Note, this Agreement or any of the
other Loan Documents (each a "Non-Performing Lender"), Agent shall inform the
other Lenders of the failure of such Non-Performing Lender to make the advance
required of such Non-Performing Lender. Upon receipt of such notice, the other
Lenders (each, a "Performing Lender") shall immediately advance to Agent the
amounts that otherwise would


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have been advanced by such Non-Performing Lender. Each Performing Lender shall
seek and request contribution from the Non-Performing Lender for any amounts
that such Performing Lender advanced to Borrower that otherwise would have been
advanced by such Non-Performing Lender. Each Lender agrees that if it is a
Non-Performing Lender, such Non-Performing Lender shall immediately reimburse
each Performing Lender for any amounts that such Performing Lender advanced to
Borrower that otherwise would have been advanced by such Non-Performing Lender.

            7. BORROWER'S REPRESENTATIONS. Borrower hereby represents and
warrants to Lenders as follows:

                  (a) Borrower has good and marketable title to the Pledged
Collateral, free and clear of all security interests, liens, claims, charges and
encumbrances of any kind or nature whatsoever, subject to the restrictions on
sale imposed by federal securities law;

                  (b) There is no restriction upon the right of Borrower to
transfer the Pledged Collateral to Agent in accordance with this Agreement and
the execution, delivery and performance by Borrower of the Note, this Agreement
or any of the other Loan Documents will not (i) violate, conflict with, result
in a breach of, or constitute a default under any agreement or instrument to
which Borrower is a party or by which Borrower is bound, (ii) result in the
creation or imposition of any lien, charge or encumbrance upon the Pledged
Collateral, except as to the lien created in favor of Lenders by this Agreement,
or (iii) violate any judgment, decree, order or award of any court, governmental
body or arbitrator, or any applicable law, rule or regulation; and

                  (c) This Agreement has been duly and validly authorized,
executed and delivered by Borrower and constitutes the legal and valid binding
obligation of Borrower, enforceable against Borrower in accordance with its
terms.

            8. BORROWER'S COVENANTS. Borrower covenants and agrees that until
Borrower's obligations under the Note, this Agreement or any of the other Loan
Documents have been fully paid and performed, Borrower shall not transfer,
assign or make or suffer to be made any pledge, hypothecation, mortgage, lien,
charge, option or encumbrance of any kind on or affecting the Pledged
Collateral, other than the lien and security interest created by this Agreement
in favor of Lenders.

            9. VOTING RIGHTS. Borrower hereby irrevocably grants, constitutes
and appoints Agent as Borrower's proxy with respect to the Pledged Collateral,
with full power, in the same manner, to the same extent, and with the same
effect as if Borrower was to do the same, to do all things which Borrower can or
could do as a shareholder of InCon Technologies, Inc.; provided, however, that
this proxy shall not be exercisable by Agent and Borrower alone shall have the
foregoing powers, so long as there is no Event of Default under this Agreement.
If any Event of Default occurs, all rights to vote the Pledged Collateral shall
immediately and


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automatically pass to Agent. Borrower hereby specifically agrees that the proxy
granted hereunder is coupled with an interest and shall be and remain
irrevocable until this Agreement is terminated as provided in this Agreement.

            10. REMEDIES.

                  (a) Upon the occurrence of an Event of Default, Agent shall
take such action, or refrain from taking such action, with respect to such Event
of Default as Agent shall deem advisable and in the best interests of each of
Lenders. In accordance with the foregoing, Agent shall be entitled to assert or
enforce any and all rights and remedies available at law or equity, including,
without limitation, all rights and remedies of a secured party under the Uniform
Commercial Code in effect in Arizona at that time. Agent may proceed with such
rights or remedies simultaneously or consecutively, and the choice of one or
more rights or remedies shall not be construed as a waiver or election barring
any other rights or remedies, all of which rights and remedies will, to the
fullest extent permitted by law, be cumulative. Borrower agrees that in the
event notice is necessary under applicable law, any notice delivered to Borrower
in the manner specified in Section 13 hereof shall constitute reasonable notice.

                  (b) In the event of any public or private sale or other
disposition, Agent and Lenders are hereby relieved from any liability or claim
for inadequacy of price, provided that the sale is conducted in a commercially
reasonable manner. At any public sale or other disposition (and at any private
sale, as permitted by applicable law), any one of Lenders may purchase the whole
or any part of the Pledged Collateral or any interest therein being sold. If any
sale or other disposition is made on credit, the Pledged Collateral so sold, or
disposed of may be retained by Agent as security until the selling price is paid
by the purchaser(s) without any liability on the part of Agent or Lenders in the
event of failure of the purchaser(s) to take up and pay for the Pledged
Collateral sold and with the right of Agent to resell the Pledged Collateral in
the event of a default by the purchaser(s). Agent shall give Borrower written
notice, pursuant to Section 13 hereof, at least ten (10) days prior to any sale
or other disposition of the Pledged Collateral, or any part thereof, pursuant to
this Section 10.

                  (c) In the event of any sale of the Pledged Collateral or any
part thereof, pursuant to this Section 10, Agent shall apply the net proceeds of
the sale in the following order of priority: (i) first, to the payment of all
costs, expenses, fees and charges, including reasonable attorneys' fees and
legal expenses, incurred by Agent in connection with the collection, sale,
delivery or preservation of the Pledged Collateral on account of the occurrence
of an Event of Default, all of which costs, expenses, fees and charges shall be
deemed to be part of the obligations secured by the Pledged Collateral; (ii)
second, to the obligations under the terms of the Note, this Agreement and any
other Loan Document; and (iii) finally, any surplus shall be paid to Borrower.


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            11. INDULGENCES, WAIVERS AND AMENDMENTS. Neither the failure nor the
delay of any party hereto to exercise any right, remedy, power or privilege
under this Agreement or any other Loan Document shall operate as a waiver
thereof, nor shall any single or partial exercise of any right, remedy, power or
privilege preclude any other or further exercise of the same or of any other
right, remedy, power or privilege, nor shall any waiver of any right, remedy,
power or privilege with respect to any occurrence be construed as a waiver of
such right, remedy, power or privilege with respect to any other occurrence. No
waiver shall be effective unless it is in writing and is signed by the party
asserted to have granted such waiver. No amendment, modification, change,
termination, 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.

            12. TERMINATION; RELEASE OF PLEDGED COLLATERAL. This Agreement and
the lien and security interest granted hereby shall terminate upon the earlier
of (a) the full and complete payment and performance by Borrower of all of its
obligations under the Note, this Agreement and any other Loan Document; (b) the
written agreement of Borrower and Lenders; or (c) the public or private sale or
other disposition of all the Pledged Collateral by Agent pursuant to Section 11
hereof. When Borrower's obligations under the Note, this Agreement and the other
Loan Documents have been fully and completely paid and performed, Agent shall
immediately deliver to Borrower a release of its interest in the Pledged
Collateral.

            13. NOTICES. Any notice or other communication with respect to this
Agreement 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.

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

            15. JURISDICTION AND VENUE. Borrower, Agent 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 the Note, this Agreement
or the other Loan Documents, or involving any other claims or allegations
arising out of the transactions evidenced or contemplated by the Note, this
Agreement


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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, Agent
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. 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, or to exercise any other right or remedy
under the Note, this Agreement or in the Loan Documents, or in the event Agent
or Lenders are made parties to any litigation because of the existence of the
Note, this 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 the Note, this
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.

            17. ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement and understanding between the parties hereto with respect to pledging
the Pledged Collateral, and supersedes all other prior and contemporaneous
agreements, understandings, inducements and conditions, express or implied, oral
or written, of any nature whatsoever with respect to pledging the Pledged
Collateral. The express terms hereof control and supersede any course of
performance or usage of the trade inconsistent with any of the terms hereof.

            18. INCONSISTENCIES; CONFLICTS. In the event of any conflict or
inconsistency between the terms of the Note, this Agreement and any of the other
Loan Documents, the provisions of this Agreement shall govern and control to the
extent necessary to resolve such conflict or inconsistency.

            19. PROVISIONS SEVERABLE. The provisions of this Agreement 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 Agreement 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.

            20. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which will be deemed to be an original as against any
party whose signature appears thereon, and all of which will together constitute
one and the same instrument.


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

                                    "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:
                                              ---------------------------


                                    "LENDERS"


                                    /s/William McCormick
                                    --------------------------------
                                    Name: William McCormick, as a Lender


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


                                    /s/William McCormick
                                    --------------------------------
                                    Name:  Xiagen Ltd.      , as a Lender


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


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

                                    Address of Ropart Investments LLC:


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                                    One East Weaver Street
                                    Greenwich, CT  06831


                                    /s/Frederick B. Rentschler
                                    --------------------------------
                                    Name:  Frederick B. Rentscher, as a Lender


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


                                    /s/ Ronald H. Lane
                                    Name:  Ronald H. Lane       , as a Lender


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



                                     "AGENT"


                                    /s/ William McCormick
                                    --------------------------------
                                    Name: William McCormick        , as Agent


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


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                                    EXHIBIT A

                      ASSIGNMENT SEPARATE FROM CERTIFICATE

            FOR VALUE RECEIVED, the undersigned does hereby sell, assign and
transfer to _________________________________ _______________________ (100)
shares of common stock of InCon Technologies, a Delaware corporation (the
"Corporation"), represented by stock certificates No. 1 in the name of Nutrition
Technology Corporation on the books of the Corporation.

            The undersigned does hereby irrevocably constitute and appoint
________________________ as its attorney-in-fact to transfer said stock on the
books of the Corporation with full power of substitution in the premises.
            Dated as of June 20, 2001.

                                    BIONUTRICS, INC., a Nevada corporation


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