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                                                                   EXHIBIT 10.91

THIS WARRANT AND THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND MAY NOT BE SOLD, OFFERED FOR SALE, ASSIGNED, TRANSFERRED OR OTHERWISE
DISPOSED OF, UNLESS REGISTERED PURSUANT TO THE PROVISIONS OF THE SECURITIES ACT
OR AN OPINION OF COUNSEL IS OBTAINED STATING THAT SUCH DISPOSITION IS IN
COMPLIANCE WITH AN AVAILABLE EXEMPTION FROM SUCH REGISTRATION.

August 1, 2003

                                  VIRAGEN, INC.

             (Incorporated under the laws of the State of Delaware)

               Warrant for the Purchase of Shares of Common Stock

No. TV-02

         FOR VALUE RECEIVED, VIRAGEN, INC. (the "Company"), a Delaware
corporation, hereby certifies that Toni Vallen (the "Holder"), is entitled,
subject to the provisions of the Warrant, to purchase from the Company up to
100,000 fully paid and non-assessable shares of Common Stock under terms and at
a price per share (the "Exercise Price") of $0.24.

         The term "Common Stock" means the Common Stock, par value $.01 per
share, of the Company as constituted on August 1, 2003 -(the "Base Date"). The
number of shares of Common Stock to be received upon the exercise of this
Warrant may be adjusted from time to time as hereinafter set forth. The shares
of Common Stock deliverable upon such exercise, and as adjusted from time to
time, are hereinafter referred to as "Warrant Stock." The term "Other
Securities" means any other equity or debt securities that may be issued by the
Company in addition thereto or in substitution for the Warrant Stock. The term
"Company" means and includes the corporation named above as well as (i) any
immediate or more remote successor corporation resulting from the merger or
consolidation of such corporation (or any immediate or more remote successor
corporation of such corporation) with another corporation, or (ii) any
corporation to which such corporation (or any immediate or more remote successor
corporation of such corporation) has transferred its property or assets as an
entirety or substantially as an entirety.

         Upon receipt by the Company of evidence satisfactory to it of the loss,
theft, destruction or mutilation of this Warrant, and (in the case of loss,
theft or destruction) of satisfactory indemnification, and upon surrender and
cancellation of this Warrant, if

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mutilated, the Company shall execute and deliver a new Warrant of like tenor and
date. Any such new Warrant executed and delivered shall constitute an additional
contractual obligation on the part of the Company, whether or not this Warrant
so lost, stolen, destroyed or mutilated shall be at any time enforceable by
anyone.

         The Holder agrees with the Company that this Warrant is issued, and all
the rights hereunder shall be held subject to, all of the conditions,
limitations and provisions set forth herein.

1.                Exercise of Warrant. Subject to the provisions herein, this
Warrant shall vest August 1, 2003 and become exercisable in whole or in part as
of the date hereof for a two (2) year period terminating on July 31, 2005 (the
"Expiration Date") or, if such day is a day on which banking institutions in New
York are authorized by law to close, then on the next succeeding day that shall
not be such a day, by presentation and surrender of this Warrant to the Company
at its principal office, or at the office of its stock transfer agent, if any,
with the Warrant Exercise Form attached hereto duly executed and accompanied by
payment (either in cash or by certified or official bank check, payable to the
order of the Company) of the Exercise Price for the number of shares specified
in such form and instruments of transfer, if appropriate, duly executed by the
Holder or his or her duly authorized attorney. If this Warrant should be
exercised in part only, the Company shall, upon surrender of this Warrant for
cancellation, execute and deliver a new Warrant evidencing the rights of the
Holder thereof to purchase the balance of the shares purchasable hereunder. The
Company shall pay any and all documentary stamp or similar issue or transfer
taxes payable in respect of the issue or delivery of shares of Common Stock on
exercise of this Warrant.

2.                Reservation of Shares. The Company will at all times reserve
for issuance and delivery upon exercise of this Warrant all shares of Common
Stock or other shares of capital stock of the Company (and Other Securities)
from time to time receivable upon exercise of this Warrant. All such shares (and
Other Securities) shall be duly authorized and, when issued upon such exercise,
shall be validly issued, fully paid and non-assessable and free of all
preemptive rights.

3.                Fractional Shares. No fractional shares or scrip representing
fractional shares shall be issued upon the exercise of this Warrant, but the
Company shall pay the holder an amount equal to the fair market value of such
fractional share of Common Stock in lieu of each fraction of a share otherwise
called for upon any exercise of this Warrant. For purposes of this Warrant, the
fair market value of a share of Common Stock shall be determined as follows:

                  (a)      If the Common Stock is listed on a National
                  Securities Exchange or admitted to unlisted trading privileges
                  on such exchange or listed for trading on the American Stock
                  Exchange system, the current market value shall be the last
                  reported sale price of the Common Stock on such exchange or
                  system on the last business day prior to the date of exercise
                  of this Warrant or, if no such

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                  sale is made on such day, the average of the closing bid and
                  asked prices for such day on such exchange or system; or

                  (b)      If the Common Stock is not so listed or admitted to
                  unlisted trading privileges, the current market value shall be
                  the mean of the last reported bid and asked prices reported by
                  the National Quotation Bureau, Inc. on the last business day
                  prior to the date of the exercise of this Warrant; or

                  (c)      If the Common Stock is not so listed or admitted to
                  unlisted trading privileges and bid and asked prices are not
                  so reported, the current market value shall be an amount, not
                  less than book value thereof as at the end of the most recent
                  fiscal year of the Company ending prior to the date of the
                  exercise of the Warrant, determined in such reasonable manner
                  as may be prescribed by the Board of Directors of the Company.

4.                Rights of the Holder. The Holder shall not, by virtue hereof,
be entitled to any rights of a stockholder in the Company, either at law or in
equity, and the rights of the Holder are limited to those expressed in this
Warrant.

5.                Anti-Dilution Provisions.

                  5.1      Adjustment for Recapitalization. If the Company shall
at any time subdivide its outstanding shares of Common Stock (or Other
Securities at the time receivable upon the exercise of the Warrant) by
recapitalization, reclassification or split-up thereof, or if the Company shall
declare a stock dividend or distribute shares of Common Stock to its
stockholders, the number of shares of Common Stock subject to this Warrant
immediately prior to such subdivision shall be proportionately increased, and
the Exercise Price shall be proportionately decreased, and if the Company shall
at any time combine the outstanding shares of Common Stock by recapitalization,
reclassification or combination thereof, the number of shares of Common Stock
subject to this Warrant immediately prior to such combination shall be
proportionately decreased, and the Exercise Price shall be proportionately
increased. Any such adjustments pursuant to this Section 5.1 shall be effective
at the close of business on the effective date of such subdivision or
combination, or if any adjustment is the result of a stock dividend or
distribution, then the effective date for such adjustment based thereof shall be
the record date therefor.

                  5.2      Adjustment for Reorganization, Consolidation, Merger,
Etc. In case of any reorganization of the Company (or any other corporation, the
securities of which are at the time receivable on the exercise of this Warrant)
after the Base Date or in case after such date the Company (or any such other
corporation) shall consolidate with or merge into another corporation or convey
all or substantially all of its assets to another corporation, then, and in each
such case, the Holder of this Warrant upon the exercise thereof as provided in
Section 1 at any time after the consummation of such reorganization,
consolidation, merger or conveyance shall be entitled to receive, in lieu of the
securities and property receivable

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upon the exercise of this Warrant prior to such consummation, the securities or
property to which such Holder would have been entitled upon such consummation if
such Holder had exercised this Warrant immediately prior thereto; in each such
case, the terms of this Warrant shall be applicable to the securities or
property receivable upon the exercise of this Warrant after such consummation.

                  5.3      Notification as to Adjustments. In each case of an
adjustment in the number of shares of Common Stock receivable on the exercise of
the Warrant, the Company at its expense will promptly compute such adjustment in
accordance with the terms of the Warrant and will notify the Holder in writing
of such adjustment within 30 days of the effective date of such adjustment. When
appropriate, notice may be given in advance as part of notices required to be
mailed to the Holder pursuant to Section 5.4 hereof.

                  5.4      Notices of Record Date, Etc. In case:

                           (a)      the Company shall take a record of the
holders of its Common Stock (or Other Securities at the time receivable upon the
exercise of the Warrant) for the purpose of entitling them to receive any
dividend (other than a cash dividend at the same rate as the rate of the last
cash dividend theretofore paid) or other distribution, or any right to subscribe
for, purchase or otherwise acquire any shares of stock of any class or any other
securities, or to receive any other right; or

                           (b)      of any capital reorganization of the
Company, any reclassification of the capital stock of the Company, any
consolidation or merger of the Company with or into another corporation, or any
conveyance of all or substantially all of the assets of the Company to another
corporation; or

                           (c)      of any voluntary or involuntary dissolution,
liquidation or winding up of the Company, then, and in each such case, the
Company shall mail or cause to be mailed to each Holder of the Warrant at the
time outstanding a notice specifying, as the case may be, (i) the date on which
a record is to be taken for the purpose of such dividend, distribution or right,
and stating the amount and character of such dividend, distribution or right, or
(ii) the date on which such reorganization, reclassification, consolidation,
merger, conveyance, dissolution, liquidation or winding up is to take place, and
the time, if any, is to be fixed, as to which the holders of record of Common
Stock (or such Other Securities at the time receivable upon the exercise of the
Warrant) shall be entitled to exchange their shares of Common Stock (or such
Other Securities) for securities or other property deliverable upon such
reorganization, reclassification, consolidation, merger, conveyance,
dissolution, liquidation or winding up. Such notice shall be mailed at least 20
days prior to the date therein specified, and the Warrant may be exercised prior
to said date during the term of the Warrant.

6.                Transfer to Comply with the Securities Act. This Warrant and
any Warrant Stock or Other Securities may not be sold, assigned, transferred,
pledge, hypothecated or

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otherwise disposed of except as follows: (a) to a person who, in the opinion of
counsel to the Company, is a person to whom this Warrant or the Warrant Stock or
Other Securities may legally be transferred without registration and without the
delivery of a current prospectus under the Securities Act with respect thereto
and then only against receipt of an agreement of such person to comply with the
provisions of this Section 6 with respect to any resale or other disposition of
such securities; or (b) to any person upon delivery of a prospectus then meeting
the requirements of the Securities Act relating to such securities and the
offering thereof for such sale or disposition, and thereafter to all successive
assignees.

         7.       Registration. The Company agrees to use its best efforts to
register the Warrant Stock underlying the Warrant on a Form S-8 under the
Securities Act within 30 day of the date hereof. The Company agrees to maintain
the registration statement as effective during the period this Warrant is
exercisable through the Expiration Date.

         8.       Notices. All notices required hereunder shall be in writing
and shall be deemed given when telegraphed, delivered personally or within two
days after mailing when mailed by certified or registered mail, return receipt
requested, to the Company or the Holder, as the case may be, for whom such
notice is intended at the address of such party as set forth on the first page,
or at such other address of which the Company or the Holder has been advised by
notice hereunder.

         9.       Applicable Law. The Warrant is issued under and shall for all
purposes be governed by and construed in accordance with the laws of the State
of Delaware.

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed on
its behalf, in its corporate name, by its duly authorized officer, all as of the
day and year first above written.

                                                      VIRAGEN, INC.

                                                  By: /s/ Dennis W. Healey
                                                      --------------------------
                                                      Dennis W. Healey
                                                      Executive Vice President
                                                      Chief Financial Officer

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                              WARRANT EXERCISE FORM

         The undersigned hereby irrevocably elects to exercise the within
Warrant to the extent of purchasing _________ shares of Common Stock of Viragen,
Inc., a Delaware corporation, and hereby makes payment of $__________ in payment
therefore.

                                                      Signature

                                                      Signature, if jointly held

                                                      Date

                       INSTRUCTIONS FOR ISSUANCE OF STOCK
         (If other than to the registered holder of the within Warrant)

Name
    (Please typewrite or print in block letters)

Address

Social Security or
Taxpayer Identification Number

Phone and Fax #'s:____________________________

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                                 ASSIGNMENT FORM

         FOR VALUE RECEIVED

hereby sells, assigns and transfers unto

(Please typewrite or print in block letters)

the right to purchase Common Stock of Viragen, Inc., a Delaware corporation,
represented by this Warrant to the extend of shares as to which such right is
exercisable and does hereby irrevocably constitute and appoint

Attorney to transfer the same on the books of the Company with full power of
substitution in the premises.

Dated:__, 200__

                                                      Signature

                                                      Signature, if jointly held

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