红曲色素高产菌的诱变选育与发酵优化

Mutation Breedingand Fermentation Optimization of the Strain with High-Yield of Monascus Red Pigment

摘要:

红曲红是一种由红曲霉生产的具有较高药用及营养价值的天然色素。为提高红曲红液态发酵产量，利用常压室温等离子体诱变技术(ARTP)对紫红曲霉（Monascus purpureus）LBBE进行诱变并优化了发酵条件。确定ARTP诱变条件为：红曲霉孢子浓度107个/mL、通气量10 SLM、功率80 W、诱变时间42 s。上述诱变条件下，经10轮诱变，红曲霉正向突变率从44.6 %降至3.8%，突变株LBBE-15的红曲红色价达到1 244 U/mL，较出发菌株提高1.26倍。红曲霉培养条件优化确定为：接种体积分数7%、硫酸锰1 g/L、初始pH 3.7。优化后的红曲红色价达到1 376 U/mL。50 L罐分批发酵显示，红曲红色价为642 U/mL。该研究结果为实现工业大规模生产提供了数据参考。

Abstract:

Monascus red pigment is a natural pigment produced by Monascus with medicinal and nutritional values. In order to improve the yield of Monascus red pigment through liquid fermentation, the mutagenesis of Monascus purpureus LBBE was performed based on atmospheric and room temperature plasma (ARTP), and the fermentation optimization was also conducted. The mutagenesis condition of ARTP was set with 107/mL of Monascus spore and 10 SLM of aeration at 80 W of power for 42 s. After 10 rounds mutagenesis under the mentioned condition, the positive mutation rate of the strain decreased from 44.6 % to 3.8 %, and the mutant LBBE-15 achieved 1 244 U/mL of the red pigment, which was 1.26 times of the original strain. The optimal culture condition of Monascus was determined as follows:7% inoculation quantity, 1 g/L manganese sulfate, and initial pH 3.7. Then, the yield of the red pigment reached 1 376 U/mL under the optimized culture condition. As indicated by batch fermentation, the mutant strain produced 642 U/mL red pigmentin 50 L jar-fermenter. The results here provided reference data for realizing industrial scale production of Monascus red pigment.