Penicillium pulvillorum

Citreoviridin. Nagel et al. have shown that Penicillium pulvillorum produces citreoviridin (156), a yellow fluorescent, neurotoxic polyene, previously... 

Penicillium ochrosalmoneum (Eupenicillium ochrosalmoneum), when cultured on rice, produced citreoviridin. Penicillium pulvillorum also produced citreoviridin in high yield, when cultured on cornmeal (Nagel et ai, 1972a). 

The polyene structure of citreoviridin suggested that this compound is derived from a polyketide e.g. (8) through the acetate polymalonate condensation pathway with the introduction of five Cj-units from methionine. In the biosynthetic studies, a strain of Penicillium pulvillorum was grown in Ushinsky medium at 25°C in stationary culture. Radioactive precursors were added to the culture 9-10 days after inoculation when the production of citreoviridin started to increase rapidly. Citreoviridin was then isolated and purified. The incorporation ratios obtained from [mc/Aj/- C]methionine and [2- " C]acetate were 70% and 5%, respectively. The radioactive citreoviridin was degraded as shown in Scheme 1. 

Penicillium citreoviride and termed citreoviridinol it is possibly biosynthetically related to (17a) by intramolecular capture of an epoxide on the trisubstituted carbon-carbon double bond. Another new fungal metabolite with a likely biogenetic relationship to the citreoviridins is the polyene pyrone citreomontanin (19), isolated from the mycelium of P.oedemontanum and P.pulvillorum this latter organism also produces citreoviridin A. 

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