Cyanotech Corp., The Kona-based producer of nutritional and health products from microalgae, said its net loss narrowed by about half during the last three months of 2007 as revenue increased.

The company reported a loss of $594,000, or 11 cents a share, in the October-to-November period. That compared with a loss of $1.19 million, or 23 cents, a year earlier.

Sales in the quarter increased by 14 percent to $2.76 million as it sold more of its natural astaxanthin product. In the same quarter a year earlier, revenues were $2.43 million.

During the quarter, the company announced it was laying off 13 workers, or about 20 percent of its workforce.