Abstract
The field of chemotaxonomy has been greatly intensified in the last years, however little to no reliability studies have been conducted to ensure its validity. The fatty acid, secondary metabolite, and volatile compound profiles of 27 fungal strains belonging to three species of the genus Penicillium were subjected to a computational reliability study to investigate their validity in the chemotaxonomy of the genus Penicillium. Values of Cohen's kappa (kappa) and significance (rho) were computed for each metabolite as a measure of agreement among the investigated fungal strains. A considerable number of fatty acids possessed negative. values proving systematic disagreement and the unreliability of fatty acids. Secondary metabolites were assigned as moderately reliable with citrinin, ochratoxin A, and palitantin being almost perfectly reliable. Eight of the volatiles possessed significant. values having a strong level of agreement. Such eight volatiles could be regarded as strong chemotaxonomic markers within the genus Penicillium regarding the species aurantiogriseum, hordei, and roqueforti. This study could be considered the first applying reliability in investigating the validity of fungal chemotaxonomy. This study also highlights the importance of undergoing reliability studies in this field of science before setting taxonomic principals based upon chemotaxonomic studies without validating it.