18D-27 |
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C.-C. LIAO, Bioresources Collection & Research Center, Food Industry Research & Development Institute, Hsinchu, 300, Taiwan P.M. WANG, L.Y. Huang, G.R. Luo, G.F. Yuan and C.C. Liao, Food Industry Research and Development Institute, P.O. Box 246, Hsinchu 300, Taiwan. Monascus pigments have been used as good sources of food colorant for centuries in oriental countries. Monascus species were cultivated using rice grain traditionally. The procedure of solid-state cultivation was very laborious and complicated, so submerged cultivation of Monascus have attracted attention continuously. However, submerged culture usually produced lower levels of pigment. In order to simulate the environments of solid-state cultivation in submerged cultivation, Monascus was immobilized in/on support materials. The organism used in this study was Monascus purpureus BCRC 38038 (obtained from the Food Industry Research and Development Institute, Hsinchu, Taiwan). The main composition of the medium was glucose (20 g/l) and monosodium glutamate (12.6 g/l). In this study, passive immobilization of M. purpureus BCRC 38038 onto different materials and pigment production were evaluated in submerged cultivation. Passive immobilization of fungi may have the advantages of less hindrance to growth of hyphal adhesion and penetration as compared to active immobilization by entrapment and binding methods. It was found that strain BCRC 38038 attached and grew in/on support materials including PU foam, nonwoven cloth, and loofah sponge, and the broth was clear during the periods of cultivation. The effects of number and size of different support materials were also investigated. Pigment production was relatively high, reaching 16 OD500 unit after 48 hrs of cultivation, by using a piece of nonwoven cloth (12*12*0.5 cm) as support material in 1-liter flask. Experiments of repeated-batch culture were carried out using immobilized cells in 1-liter flask. At the end of a batch culture, a portion of the broth was replaced with fresh medium. Pigment production was stable, reaching about 16 OD500 unit, after one repeated culture cycle by replacing 1/4, 1/2, or total volume of broth. Hence, passive immobilization of Monascus with nonwoven cloth by repeated-batch operation mode could be used for pigment production.
Session 18D, Food Microbiology: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |