紅麴黃色素 monascin 與 ankaflavin 最適生產條件之研究

Abstract

The market of the natural products on an international level is in a phase of extraordinary expansion. The pigments of Monascus spp. are secondary metabolites belong to the group of polyketides. Monascus pigments composed of yellow, orange and red pigments which belonged to an azaphilone skeleton, and have been reported to possess anti-inflammantory and anticancer activities. In this study, Monascus purpureus NTU 568 was fermented under solid and submerged conditions, and culture conditions (cultural time, initial pH value, carbon source, nitrogen source, cultural temperature and ethanol addition) were selected to investigate the effect on monascin and ankaflavin production. Furthermore, response surface methodology (RSM) was applied in order to seek the optimal culture conditions. Culture conditions were as following: with 3.8% carbon source concentration, initial pH value were 5.2 and adding 0.5% ethanol, after 8-days cultivation the production of monascin and ankaflavin would be increase from 9.8 mg/g to 17.4 mg/g and 4.5 to 6.6 mg/g respectively, citrinin would be increase from 3.3 ppm to 4.4 ppm in submerged fermentation. In addition, while dioscorea was used as the solid culture substrate, and the optimal culture conditions were as following: cultural temperature 35oC, 200 mL water and 0.5% ethanol were added, after 8-days cultivation, the production of monascin and ankaflavin would be increase from 3.4 mg/g to 9.4 mg/g and 1.3 to 3.4 mg/g respectively, citrinin would be decreased from 5.4 ppm to 2.9 ppm. Afterward, the optimal cultivation conditions were carried out using stirred tank fermentor and airlift fermentor. The production of monascin and ankaflavin were 28.1 mg/g and 15.8 mg/g respectively, citrinin concentration was 3.3 mg/kg in strried tank fermentor; on the other hand, the production of monascin and ankaflavin were 25.9 mg/g and 14.3 mg/g respectively, citrinin concentration was 4.8 mg/kg in airlift fermentor.