Investigating of growth and pigment production by Penicillium aculeatum in whey

Molds have the ability to produce different pigments with consumption as food color. This study aimed to investigate the effect of the factors affecting the production of pigment by the Penicillium aculeatum. In this study، the combined effect of pH (5، 6. 5 and 8)، temperatures (25، 30 and35) and agitation speed levels (100 and 150 rpm) on pigment production and mycelial growth of Penicillium aculeatum was investigated in submerged whey media. After ten days of incubation، the produced pigment was isolated and purified using filtration، centrifugation and ethyl acetate solvent. All experi-ments were conducted in a completely randomized factorial design with three replications. The data were compared using the mean Tukey’s test and data analysis was performed using the statistical soft-ware JUMP V 8. 0. 1. The best production of pigment (1. 38 g/L) was obtained with pH value of 6. 5، temperature of 30 ˚C and agitation speed of 150 rpm. In contrast، the maximal biomass concentration (11. 12 g/L) was obtained at pH value of 8، temperature of 30˚C and agitation speed of 100rpm. These results demonstrated that biomass and pigment production were not directly associated. This study showed that the effect of pH and temperature on pigment production are significant (p<0. 05) but agita-tion speed not significant (p≥0. 05). pH has no significant effect of growth (p≥0. 05)، In contrast، tem-perature and agitation speed have a significant effect on the growth (p<0. 05).