The Monascus mutant with high yield of yellow pigment was obtained by using conventional relevant mutation techniques, e.g., treating with physical mutagens(such as UV light) and chemical substances (such as N-methyl-N'-nitro-N-nitrosoguanidine). The yellow pigment was scanned from 300 nm to 600 nm with UV spectrometer, the maximal absorption was determined at 410 nm. The growth characteristic of Monascus mutant is stable, the yellow pigment value and colour hue in liquid fermentation can reach 100 U/mL and 3.5 respectively. The yellow pigment is stable from pH 3 to pH 8, but the precipitation appeared as the pH of the pigment solution lower than 3.
