Abstract
A strain of Macrosporium porri Elliott, when grown at 25° on 2% glucose solution of stone-leek decoction, gives rise to a hitherto undescribed pigment to which the name “macrosporin” is proposed. Optimum cultural condition for the production of the pigment and the method of its isolation are described here. Macrosporin, C16H12O5, crystallizes as orange-yellow rhombic and melts at 300-302° with decomposition. General properties of macrosporin, its diacetate, m. p. 209-210°, and trimethylether, m. p. 260-261°, are described. Macrosporin is recognized to be a hydroxyanthraquinone derivative from the results of elementary analysis, molecular weight determination, and ultra-violet and infra-red spectra.
