1,200 1,300 



CM-' 

 800 600 



400 



Figure 4. — Infrared absorption spectra of toxins in CCl^. The instrument used provides spectra in 

 two regions, low and high wavelength, as indicated. (Reference cell contained air.) Key to spectra; 

 CCI4, pure solvent; IIB, substance II (bloom sample) ; IIC, substance II (culture sample) ; I, sub- 

 stance I (bloom sample) . 



observation is based on a study of infrared 

 spectral data (table 4). These data also indicate 

 that substances I and II differ; notably a 

 carbonyl group is indicated by the spectrum of 

 substance I (fig. 4) but not by the spectrum of 

 substance II. 



2. The major toxin (substance II) does not 

 contain nitrogen according to qualitative and 

 quantitative analysis (table 2). This appears to 

 be the first report of a phosphorus-containing 

 toxin isolated from dinoflagellate blooms, a fact 

 that is of considerable interest because organo- 

 phosphorus compounds have been used as model 

 compounds in the study of factors controlling 

 nerve activity (Nachmansohn, 1961). 



3. An empirical formula of C90H162O17P was 

 calculated from the mean values of the quanti- 

 tative elemental analytical data of substance II 

 (table 2). Substance I could not be isolated in 

 the quantity required for elemental analysis. As 

 usual, the validity of the empirical formula is 



governed by the validity of the elemental analy- 

 sis. In this instance, the reliability is indicated 

 by replication of carbon and hydrogen analysis 

 for diff"erent samples. The phosphorus analysis 

 is the limiting factor in the accuracy of the 

 formula. The results with a "spiked" sample 

 suggest decomposition is complete ; the values 

 are within the experimental error. 



4. A molecular weight of 650 was determined 

 for substance II. This is about one-half the 

 value of the empirical formula weight (1,545) 

 and indicates each unit of substance II exists 

 as two particles in chloroform (and presumably 

 in other polar solvents). The observation gives 

 no infonnation about the relative sizes of the 

 two particles. The two particles must be similar 

 in properties because only one band is obtained 

 with chromatography (thin-layer or column) 

 using silica gel. Also, two bands indicative of 

 two components were obtained when substance 



CHEMICAL AND PHYSICAL PROPERTIES OF TWO TOXINS FROM RED-TIDE ORGANISM 



441 



