A chemotaxonomic evaluation of selected members of the genus Amanita

The distributions of cyclopeptides, tryptamine derivatives and acyclic quaternary ammonium bases related to muscarine were examined in selected members of the genus Amanita in an effort to evaluate the usefulness of these compounds as adjuncts to morphological data in the delineation of each organism examined. Included in the investigation were A. virosa Lam. ex Secr., A. bisporigera Atk., white-carpophored amanitas displaying morphological features intermediate between those of A. virosa and A. bisporigera, A. phalloides (Vaill. ex Fr.) Secr., A. citrina (Schaeff.) S. F. Gray, A. citrina var. lavendula Coker, and three white-carpophored amanitas collected in Florida for which no specific epithets could be determined.

Cyclopeptides were detected in all members of the genus examined with the exception of A. citrina. A total of seven known cyclopeptides were detected including α-AMA, β-AMA, γ-AMA, amanin, phalloidin and phallacidin. In addition, seven compounds believed to be amatoxins, but as yet uncharacterized, were detected.

Tryptamine derivatives were more limited in their distribution with detectable quantities occurring in only five examined members of the genus including A. citrina, A. citrina var. lavendula and the three white-carpophored Florida amanitas. Amanita citrina was the taxon with the greatest variety of derivatives producing serotonin, N-methylserotonin, bufotenine, bufotenine-N-Oxide and 5-methoxy-N,N-dimethyltryptamine. Amanita citrina var. lavendula possessed a similar tryptamine profile but lacked detectable quantities of the latter compound, while the Florida specimens produced only trace amounts of serotonin.

Choline was the only muscarine related quaternary ammonium base detected. It was present in all taxa examined. The ubiquitous nature of choline negated its usefulness in the characterization of individual taxa.

However, the reproducibility of the limited patterns of distribution of cyclopeptides and tryptamine derivatives was a valuable aid in the definitions of the organisms examined. On the basis of extensive morphological and biochemical analyses, A. bisporigera Atk. was synonomized with A. virosa Lam. ex Secr, and the rank of A. citrina var. lavendula was elevated to species [A. lavendula (Coker) Peterson stat. nov.]. Complete descriptions, including morphological and chemical characteristics were compiled for each of the organisms.