Exhibit (a)(5)(D)

                             [PURE WORLD LETTERHEAD]

                                                                   June 17, 2005

Dear Optionee:

      As you are aware, Pure World, Inc. has signed a merger agreement to be
acquired by Naturex S.A. The acquisition will be effected by a tender offer by
Naturex for all of the outstanding shares of Pure World common stock, to be
followed by a merger between Pure World and a subsidiary of Naturex. This will
result in Pure World becoming a wholly owned subsidiary of Naturex. Enclosed for
your information is a copy of the Schedule 14D-9, which describes the tender
offer and the merger, as well as an information statement for Naturex's possible
appointment of members to our board of directors.

      As we prepare for the completion of the merger, we are working toward
ensuring a smooth transition. Under the terms of the merger agreement, upon the
merger, outstanding options under Pure World's stock option plans and other
stock option agreements with Pure World are to be cancelled and cashed out as
described below.

Cash Out and Cancellation of Options

      Under the merger agreement, if you consent by signing and returning this
letter, you will be entitled to receive a cash payment shortly after completion
of the merger equal to the spread value of your unexercised outstanding options,
whether or not they have vested, under the 1991 Non-Qualified Stock Option Plan,
the 1997 Non-Qualified Stock Option Plan and/or an option agreement entered into
outside of the plans. This spread value is the result of multiplying the number
of shares that are subject to an outstanding option immediately prior to the
merger by the difference between the $4.30 per share acquisition price of the
common stock of the Company and the per share exercise price of the option.

      Example: Assume you hold unexercised options under our stock plan to buy
100 shares at an exercise price of $2.00 per share. The cash payment amount to
which you would be entitled based on the spread value is $230.00 (i.e., 100 x
($4.30-$2.00)). All options with an exercise price per share of $4.30 or
greater, because they are at or above the per share acquisition price, will not
be entitled to any cash payment.

      Please note that if the exercise price of your option is $4.30 or higher,
you will not receive any payment for cancellation of your option.

Tax Withholding

      Any cash payment you receive for your unexercised outstanding options will
be taxable to you as ordinary income for federal income tax purposes. Such
income will also be subject to federal income and employment (FICA) tax
withholding.


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Agreement and Acknowledgement

      Attached to this letter is Annex A, which lists, as of June 17, 2005, each
unexercised option that you hold under any of our stock plans. In order to
ensure that you receive the correct cash payment for your unexercised options as
quickly as possible following the merger, we wish to confirm with you that our
records of your option awards are accurate.

      Please review this letter and the information set forth in Annex A. By
signing this letter, you hereby agree and acknowledge that (i) the attached
Annex A completely and accurately lists all the unexercised outstanding stock
options as of the date of this letter that were granted to you under any of our
stock plans or under any other agreement, plan or arrangement with the Company,
(ii) the cash out payment as described in this letter, less applicable tax
withholding, when made, shall constitute complete satisfaction of any and all
obligations of the Company in connection with any option or any of the plans or
other agreements or arrangements of the Company under which any option was
granted, and (iii) you have no further rights or claims to any additional
payments or benefits in respect of your options.

      Please indicate your agreement and acknowledgement to the foregoing by
signing, dating and returning one copy of this letter as soon as possible, and
no later than 5:00 p.m. (Eastern time) on July 5, 2005. You should send the
letter to the attention of Sue Ann Merrill, Chief Financial Officer via fax at
908-234-9355 or via inter-office mail. You should retain a copy for your
records.

      This document was first mailed to Optionees on or about June 17, 2005.

      If you believe any information contained in Annex A is inaccurate or
incomplete, or if you have any questions, please call Sue Ann Merrill as soon as
possible at 908-234-9220.

                                        Very truly yours,


                                        /s/ Qun Yi Zheng
                                        ----------------------------------------
                                        Qun Yi Zheng
                                        President and Chief Operating Officer

Agreement and Acknowledgment:


_______________________________
Signature

_______________________________
Name (Please print)

_______________________________
Date



                                     Annex A