KAILUA KONA, Hawaii.-November 10, 2003- – Cyanotech Corporation (Nasdaq: CYAN), a world leader in producing high-value natural products from microalgae, and Earthrise Nutritionals, Inc. (Petaluma, CA), today jointly announced that the US Food and Drug Administration (FDA) has no questions about the companies’ determination that Spirulina is Generally Recognized as Safe (GRAS) for addition to a variety of foods.

Spirulina is a dried form of the common blue-green microalgae (Cyanobacteria), Arthrospira platensis. Cultivated in the United States by Cyanotech and Earthrise, Spirulina is marketed as a nutritional supplement and is noted for its content of fatty acids, vitamins, beta-carotene, zeaxanthin, phycocyanin and vegetable protein.

In March 2003, Cyanotech and Earthrise submitted a joint notice to the FDA reporting their determination, through scientific procedures, that the Spirulina cultivated by both companies is GRAS for addition to a variety of foods. Conclusion of the notification procedure (by the FDA’s written response) provides assurance to food manufacturers and consumers that the FDA has had an opportunity to review the safety evaluation of Spirulina for its intended use in specialty food bars, powdered nutritional drink mixes, snacks such as popcorn, and as a condiment in salads and pasta.

Speaking on behalf of both companies were John E. Dore, Ph.D., Scientific Director for Cyanotech and Amha Belay, Ph.D., Scientific Director for Earthrise. “We are gratified that the FDA had no objection to our GRAS determination for Spirulina. This added safety assurance is a benefit we are pleased to offer our customers in the functional food and dietary supplement markets and it paves the way for Spirulina’s use in other food products.”

ABOUT CYANOTECH – Cyanotech Corporation, a world leader in microalgae technology, produces high-value natural products from microalgae and is the world's largest commercial producer of natural astaxanthin (pronounced "asta-zan-thin") from microalgae. Products include BioAstin® natural astaxanthin, a powerful antioxidant with expanding application as a human nutraceutical; NatuRose® natural astaxanthin for the aquaculture and animal feed industries; Spirulina Pacifica®, a nutrient-rich dietary supplement; and phycobiliproteins, which are fluorescent pigments used in the immunological diagnostics market. Spirulina Pacifica and BioAstin are sold directly online through the Company's website, www.nutrex-hawaii.com, as well as through resellers worldwide in over 30 countries. Corporate and product information is available at www.cyanotech.com.

SAFE HARBOR – Except for statements of historical fact, the statements in this press release are forward-looking. Such statements are subject to a number of risks and uncertainties that could cause actual results to differ materially from the statements made. These factors include, but are not limited to, general economic conditions, forecasts of sales in future periods, changes in sales levels to our largest customers, weather patterns, risks associated with the acceptance of new products, competition, foreign exchange fluctuations, government regulation, and other factors more fully detailed in the Company’s recent Form 10-Q and annual Form 10-K filings with the Securities and Exchange Commission.