Deoxycylindrospermopsin, an analog of cylindrospermopsin from Cylindrospermopsis raciborskii

Cylindrospermopsin (CYN) is a hepatotoxic alkaloid found in the blue-green alga Cylindrospermopsis raciborskii (C. raciborskii). Data indicating CYN a lone does not account for the toxicity of freeze dried cultures of C. racib orskii have been presented recently. In an attempt to explain these data, w e have purified and characterized the structure of an analog of CYN, deoxyc ylindrospermopsin (deoxy-CYN). Three mice dosed intraperitoneally (IP) with 0.8 mg/kg of deoxy-CYN showed no toxicity after 5 days. Comparison with th e toxicity of CYN (5 day median lethal dose approximately 0.2 mg/kg IF) and its relative abundance in C. raciborskii suggest deoxy-CYN does not contri bute significantly to the toxicity of C. raciborskii. The additional toxici ty of freeze dried C. raciborskii over pure CYN, therefore, remains unexpla ined. (C) 1999 by John Wiley & Sons, Inc.