Abstract: In this paper, pigment separation by trihalomethanes extraction combined with resin absorption (THMS-Resin) was investigated. The performance of the recovered Triton X-100 in the extractive fermentation was also studied. Results showed that the Monascus pigments and Triton X-100 could be well separated through the combined method. The recovery of Triton X-100 and yellow pigments with high antioxidant activity was 78% and 52%, respectively. The recycled Triton X-100 exhibited excellent performance for cell growth and pigment metabolism while maintaining the extraction performance. Meanwhile, the extractive fermentation with a proper mixture of the new and recycled Triton X-100 could significantly promote the synthesis of both intracellular and extracellular Monascus pigment, resulting in a 35% increase of the total pigment yield. Five cycles of extractive fermentation were conducted. In each cycle, the average recovery of Triton X-100 was about 80% with a good biocompatibility; cell growth was stable and the extraction efficiency and metabolism were high. The relative content of extracellular and intracellular yellow pigment was 1.0 and 0.6, respectively. This method showed potential applications in obtaining high yield of Monascus yellow pigments while promoting the reuse of Triton X-100.

Key words: Monascus spp., extractive fermentation, pigment separation, surfactant reutilization