Isolation and identification of citrinin produced by Penicillium lanosum

Penicillium lanosum, when grown on corn, produces a metabolite which increases water intake and excretion by chicks. During a 5-hr test period, chicks fed inoculated corn as the only feed began excreting water within 2 hr and excreted as much as 36 ml, whereas chicks fed untreated corn did not excrete measurable amounts. Chicks fed the inoculated corn drank more water than those fed untreated corn. The metabolite could not be extracted from oven-dried corn but was removed from air-dried corn which had been moistened with acid and extracted with chloroform and then with methanol. It was soluble in 1% sodium bicarbonate and precipitated as yellow cystals when the solution was acidified to pH 1.5. The precipitate was identified as citrinin based on the results of thin layer chromatography, ultraviolet, infrared, mass spectrometer, fluorescence excitation and emission, and nuclear magnetic resonance spectra.