PRODUCTION OF MONASCUS PURPUREUS PIGMENTS; INFLUENCED BY AMIDASE AND ACID PROTEASE ACTIVITY

Monascus purpureus grown on rice secretes several polyketide pigments used for coloring foods. The amidase enzymes, L-asparaginase and L-glutaminase activities were identified by rapid plate assay. The pink zone formed around colonies of M. purpureus (Microbial Type Culture Collection [MTCC] 410), hyper pigment (Central Food Research [CFR] 410-11) and albino (CFR 410-22) were 2.0, 2.4 and 1.2 cm, respectively. The L-asparaginase (0.103 IU) and L-glutaminase (0.139 IU) activity was comparatively more in CFR 410-11 than MTCC 410 and CFR 410-22. Higher acid protease activity (5,170 Units) was observed in CFR 410-22. The mutant CFR 410-11 has secreted more red pigment cultured on rice (2.248 optical density [OD] units) and in broth (0.841 OD units). Significant difference in amidase and acid protease activities of MTCC 410 and its mutant CFR 410-11 and CFR 410-22 have revealed the importance of these enzymes in pigment production.