PURE Bioscience Files Additional U.S. Patent on Silver Dihydrogen Citrate Technology; New Patent Covers Expanded Potential Uses of PURE's Axenohl Antimicrobial.

Business Editors/Health/Medical Writers

SAN DIEGO--(BUSINESS WIRE)--June 7, 2004

PURE Bioscience (OTCBB:PURE) today announced that it has filed an additional United States patent covering multiple potential uses for its Axenohl(R) (silver dihydrogen citrate) antimicrobial technology including the treatment of specific types of bacteria, fungus and viruses, as well as medical treatment and the preservation of consumable and non-consumable products.

The additional Disinfectant and Method of Use patent application was filed in May 2004 and is the seventh Axenohl related patent application filed in the United States covering inventive aspects of manufacturing, composition and formulations of PURE's Axenohl technology.

Michael L. Krall, President and CEO of PURE Bioscience, stated, "We are pleased with the expanding portfolio of worldwide patents and patent applications for PURE's Axenohl technology. We have identified a wide range of potential uses and applications of silver dihydrogen citrate in many diverse fields, and as new potential uses continue to be discovered, we will continue to proactively protect our Axenohl related intellectual property."

PURE has already obtained two U.S. patents related to the Axenohl technology: U.S. Patent 6,197,814 for the original Axenohl disinfectant and method of making, and Patent 6,583,176 covering the Axenohl aqueous disinfectant in combination with ethyl alcohol.

In addition, PURE has received national patents in Australia and New Zealand as well as regional patents in the Eurasian and OAPI (Organisation Africaine de la Propriete Intellectuelle) regions of the world. National patent applications are pending in Brazil, Canada, China, Japan and Mexico as well as the European and the ARIPO (African Regional Industrial Property Organization) regions of the world. The Axenohl International Patent Application was published by the World Intellectual Property Organization (www.wipo.org) on April 22, 1999 under publication Number WO 99/18790.

The inventor of Axenohl is Mr. Andrew B. Arata, President of ETI-H2O, a wholly owned subsidiary of PURE Bioscience.

PURE Bioscience's new molecule, silver dihydrogen citrate (trade name Axenohl), is an electrolytically generated source of stabilized ionic silver that can serve as the basis for a broad range of products in diverse markets. Axenohl liquid is colorless, odorless, tasteless, non-caustic and formulates well with other compounds. Axenohl-based antimicrobial technology is distinguished from competitors in the marketplace because of its superior efficacy combined with reduced toxicity. PURE currently has Environmental Protection Agency (EPA) registration for its 2400-parts per million (ppm) technical grade concentrate as well as for its Axen and Axen30(R) hard surface disinfectant products for commercial, industrial and consumer applications. The Company plans to register several new products with the EPA this year.

Enormous Market Potential

Axenohl technologies lead today's global trend toward industry and consumer use of "green" products while providing competitive advantages in efficacy and safety. PURE has obtained regulatory approvals for its Axen30(R) hard surface disinfectant products in restaurants, homes and medical facilities. In addition, PURE recently received EPA approval to expand its claims to include use in childcare facilities. Axen30 is distinguished from many of the leading commercial and consumer disinfecting products because of its superior efficacy combined with its lower toxicity.

In addition to EPA approved uses of Axenohl technology, PURE, in conjunction with Therapeutics, Incorporated, is aggressively pursuing the development and commercialization of Food and Drug Administration (FDA) regulated silver dihydrogen citrate based healthcare products. Initial investigations show that silver dihydrogen citrate's broad spectrum of effectiveness combined with its low toxicity and low potential to induce bacterial resistance may provide important therapeutic advances in treatment of a number of medical diseases and conditions. PURE announced in May that Therapeutics is currently pursuing several potential silver dihydrogen citrate-based women's health products and has initiated work on a lead product for which they intend to pursue FDA approval. Therapeutics expects its development efforts will lead to the filing of Investigational New Drug (IND) with the US Food and Drug Administration (FDA).

About PURE Bioscience

PURE Bioscience (PURE) develops and markets technology-based products in the bioscience and water treatment sectors to provide non-toxic solutions to global health challenges. PURE's proprietary high efficacy/low toxicity bioscience technologies, including its Axenohl(R) antimicrobials and Triglycylboride(TM) pesticides, represent innovative advances in diverse markets. PURE is currently America's leader in pharmaceutical water purification with its Fillmaster(R) equipment, and the Company has expanded into residential water treatment with its Nutripure(R) water filtration systems. PURE Bioscience is headquartered in El Cajon, California (San Diego metropolitan area) and its common stock is listed on the OTC Bulletin Board under the symbol "PURE." Incorporated in 1992, PURE Bioscience was formerly named Innovative Medical Services.

This press release includes statements that may constitute "forward-looking" statements, usually containing the words "believe," "estimate," "project," "expect" or similar expressions. These statements are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements inherently involve risks and uncertainties that could cause actual results to differ materially from the forward-looking statements. Factors that would cause or contribute to such differences include, but are not limited to, acceptance of the Company's current and future products and services in the marketplace, the ability of the Company to develop effective new products and receive regulatory approvals of such products, competitive factors, dependence upon third-party vendors, and other risks detailed in the Company's periodic report filings with the Securities and Exchange Commission. By making these forward-looking statements, the Company undertakes no obligation to update these statements for revisions or changes after the date of this release.