Kona-based Cyanotech Corp. has ousted its president and chief executive officer for undisclosed reasons.

The company's board removed Andrew Jacobson as president and CEO, about two years after he began with the company. The board named David I. Rosenthal as interim CEO and president while it searches for a new executive.

Company spokesman Bruce Russell and the company's co-founder, Gerald Cysewski, who remains an executive vice president and is a board member, declined to comment further than what was publicly released. Jacobson also declined comment.

“;It's exactly as the press released stated,”; Cysewski said.

The abrupt and briefly worded press release stated Rosenthal replaces Jacobson, “;who was removed from his responsibilities”; as president and CEO. The language used was unusual for a press release on a top-end executive leaving a company.

After yesterday's news of the firing was released, Cyanotech's stock dropped by 12.1 percent to $3.86 a share.

Cyanotech has enjoyed growth in recent quarters and fiscal years. In fiscal 2007 the company posted a $7.4 million loss, then a $1.1 million loss a year later. In fiscal 2009 the company had a net income of $1.1 million.

Rosenthal has served on Cyanotech's board since 2000 and is a member of the audit committee. Most recently he was chief financial officer of special food company Hickory Farms Inc.

He also has served as chief financial officer of several publicly held companies, including SpectraLink Corp., StarTrek Inc. and Celestial Seasonings Inc.

Jacobson joined Cyanotech in May 2008. He previously was president of the personal care division of the Hain Celestial Group and president of Natural Products.