From clams, chromatogram

One of the first applications of the HPLC method was the investigation of differences in toxin profiles between shellfish species from various localities ( ). It became apparent immediately that there were vast differences in these toxin profiles even among shellfish from the same beach. There were subtle differences between the various shellfish species, and butter clams had a completely different suite of toxins than the other clams and mussels. It was presumed that all of the shellfish fed on the same dinoflagellate population, so there must have been other factors influencing toxin profiles such as differences in toxin uptake, release, or metabolism. These presumptions were strengthened when toxin profiles in the littleneck clam (Prototheca Staminea) were examined. It was found that, in this species, none of the toxin peaks in the HPLC chromatogram had retention times that matched the normal PSP toxins. It was evident that some alteration in toxin structure had occurred that was unique in this particular shellfish species. 

Figure 4B. Chromatogram illustrating the studies conducted on the enzymatic conversion of the PSP toxins to decarbamoyl metabolites (appended with an M in these figures). Conversion of a mixture of Cl and C2 by the clam enzymes was chromatographically distinct from conversion to GTX II and GTX III with weak acid.

Figure 6. A-Chromatogram of toxic butter clam extract showing the presence of the PSP toxins. B-Chromatogram of extract from non-toxic (bioassay) mussels showing the presence of a trace of GTX II, GTX III, and C. Conditions as in Table I with gradient shown in Figure 4.

A gas chromatogram obtained from the analysis of 200 mg of clams exposed to a South Louisiana crude oil is shown in Figure 12. The naphthalenes are particularly discernible. Although the method works well for benzene, toluene, and xylenes, it is even better for the naphthalenes, because there are fewer interferences in that region of the chromatogram. Essentially quantitative recovery of dimethylnaphtha-lenes is obtained. The method was applied very successfully to the analysis of over 100 samples. It was particularly useful in the analysis of fish fry, fish eggs, and liver samples using 25-100 mg of material. The... 

Figure 12. Gas chromatogram of volatiles from 0.2 g of clams exposed to South Louisiana crude oil...

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