**Exhibit 31.1**

 

Certification Pursuant

To 18 U. S. C. Section 1350,

As Adopted Pursuant To

Section 302 of the Sarbanes-Oxley Act of 2002

 

I,David I. Rosenthal, Interim President and Chief Executive Officer certifythat:

 

1.             I have reviewed thisquarterly report on Form 10-Q of Cyanotech Corporation;

 

2.             Based on my knowledge, thisreport does not contain any untrue statement of a material fact or omit tostate a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading withrespect to the period covered by this report;

 

3.             Based on my knowledge, thefinancial statements, and other financial information included in this report,fairly present in all material respects the financial condition, results ofoperations and cash flows of the registrant as of, and for, the periodspresented in this report;

 

4.             The registrant’s othercertifying officers and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange ActRules 13a-15(e) or 15d-15(e)) and internal control over financialreporting (as defined in Exchange Act Rules 13a-15(f) and15d-15(f))for the registrant and we have:

 

a)             Designed suchdisclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

 

b)             Designed suchinternal control over financial reporting, or caused such internal control overfinancial reporting to be designed under our supervision, to provide reasonableassurance regarding the reliability of financial reporting and the preparationof financial statements for external purposes in accordance with generallyaccepted accounting principles;

 

c)              Evaluated theeffectiveness of the registrant’s disclosure controls and procedures and presentedin this report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this reportbased on such evaluation; and

 

d)             Disclosed inthis report any change in the registrant’s internal control over financialreporting that occurred during the registrant’s most recent fiscal quarter (theregistrant’s fourth quarter in the case of an annual report) that hasmaterially affected, or is reasonably likely to materially affect, theregistrant’s internal control over financial reporting; and

 

5.             The registrant’s othercertifying officer and I have disclosed, based on our most recent evaluation ofinternal control over financial reporting, to the registrant’s auditors and theaudit committee of registrant’s board of directors (or persons performing theequivalent functions):

 

a)             All significantdeficiencies and material weaknesses in the design or operation of internalcontrols over financial reporting which are reasonably likely to adverselyaffect the registrant’s ability to record, process, summarize and reportfinancial information; and

 

b)             Any fraud,whether or not material, that involves management or other employees who have asignificant role in the registrant’s internal controls over financialreporting.

 
| Date:  November 10, 2010 | /s/ David I. Rosenthal                                                                                                    |
|-------------------------------|---------------------------------------------------------------------------------------------------------------------------|
|                          | David I. Rosenthal                                                                                                        |
| * *                      | *Interim President and Chief Executive Officer and  Director**(Performing the Functions of Principal Executive  Officer)* |

 

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