圆红冬孢酵母利用废糖蜜合成微生物油脂及类胡萝卜素

Production of microbial oils and carotenoids by Rhodosporidium toruloides with waste molasses as substrate

圆红冬孢酵母(Rhodosporidium toruloides)具有底物谱广、性能稳定和细胞含油量高等优点,是优良的微生物油脂生产工厂,而且具有高产类胡萝卜素的能力,极具开发潜力。为提高微生物的油脂和类胡萝卜素产量并降低成本,通过糖蜜与葡萄糖共添加的双糖策略、不外源添加有机氮源、限制磷酸盐的方式,成功开发R.toruloides Z11利用廉价碳源糖蜜高产微生物油脂和类胡萝卜素的新型发酵方式。与单一葡萄糖作为碳源发酵培养相比,结合多种发酵策略,可使R.toruloides Z11生物量(OD_(600))提升至379.0±0.3,提高了2.72倍,油脂质量分数达到68.9%、类胡萝卜素含量达到2.58 mg/g。

Rhodosporidium toruloides is an excellent microbial oil production strain due to its wide substrate spectrum,stable performance and high cell oil content.Moreover,it can be used to produce valuable carotenoids with high yield,which has high valuable potential.Herein,we successfully developed a new fermentation method for the conversion of low-cost carbon source molasses to highly valuable microbial oil and carotenoids using R.toruloides Z11.By using the disaccharide strategy of co-adding molasses and glucose for the conversion,this method could not only save cost,but also increase microbial oil and carotenoid production.Notably,this process was conducted without exogenous addition of organic nitrogen sources and limiting phosphate.Based on previous results that the two-stage regulation strategy of temperature and pH could improve the fermentation biomass,oil content and carotenoids production,we explored a variety of fermentation strategies.Compared with the fermentation using single glucose as carbon source,the disaccharide strategy with R.toruloides Z11 led to 2.72-fold increase for biomass(OD_(600),up to 379.0±0.3).Meanwhile,the oil content and the carotenoid level reached 68.9%and 2.58 mg/g,respectively.