Comparative study of Monascus sanguineus and Monascus purpureus as potential sources for red pigment production
by Rashmi Dikshit
Monascus spp. namely Monascus sanguineus was isolated from pomegranate (Punica granatum). In this study, the isolated M. sanguineus was compared with M. purpureus MTCC410 procured from MTCC Chandigarh, India for optimizing the red pigment yield. It was observed that both strains had produced maximum red pigment on the 16th day of incubation (21.9 CVU/ml for M. sanguineus & 16.9 CVU/ml for M. purpureus). Both strains had shown 30°C as a favorable temperature for microbial growth and pigment production. The maximum pigmentation was observed at pH 6.5 (33.9 CVU/ml) for Monascus sanguineus whereas M. purpureus produced maximum pigment at pH 5.5(16.6 CVU/ml). Oryza spp. (local unpolished rice) was found as the best solid substrate for both the strains (M. sanguineus 6.5 CVU/gds and M. purpureus 12.5 CVU/gds). When substrates were supplemented with glucose, a multi-fold increase in the pigment yield was observed with M. sanguineus, whereas no positive impact of glucose was observed with M. purpureus. For variable N sources, M. sanguineus showed maximum pigment with 1% peptone whereas M. purpureus showed similar results with substrate supplemented with 5% yeast extract and MSG. Both strains had shown anti-bacterial activity against gram positive bacteria. Presence of citrinin was confirmed in both the strains by LC-MS.