Jacobus Stark

Penicillium discolor, a new species from cheese, nuts and vegetables.

The new species Penicillium discolor, frequently isolated from nuts, vegetables and cheese is described. It is characterised by rough, dark green conidia, synnemateous growth on malt agar and the production of the secondary metabolites chaetoglobosins A, B and C, palitantin, cyclopenin, cyclopenol, cyclopeptin, dehydrocyclopeptin, viridicatin and viridicatol. It also produces the mouldy smelling compounds geosmin and 2-methyl-isoborneol, and a series of specific orange to red pigments on yeast extract sucrose agar, hence the epithet discolor. P. discolor resembles P. echinulatum morphologically but on basis of the secondary metabolites is also related to P. expansum, P. solitum and P. crustosum.