Dipartimento di Agraria, Università degli Studi di Sassari, Viale Italia 39, 07100 Sassari, Italy.
World J Microbiol Biotechnol. 2013 Jun;29(6):1009-17. doi: 10.1007/s11274-013-1264-x. Epub 2013 Jan 26.
In this work eighteen red yeasts were screened for carotenoids production on glycerol containing medium. Strain C2.5t1 of Rhodotorula glutinis, that showed the highest productivity, was UV mutagenized. Mutant 400A15, that exhibited a 280 % increase in β-carotene production in respect to the parental strain, was selected. A central composite design was applied to 400A15 to optimize carotenoids and biomass productions. Regression analyses of the quadratic polynomial equations obtained (R(2) = 0.87 and 0.94, for carotenoids and biomass, respectively) suggest that the models are reliable and significant (P < 0.0001) in the prediction of carotenoids and biomass productions on the basis of the concentrations of crude glycerol, yeast extract and peptone. Accordingly, total carotenoids production achieved (14.07 ± 1.45 mg l(-1)) under optimized growth conditions was not statistically different from the maximal predicted (14.64 ± 1.57 mg l(-1)) (P < 0.05), and it was about 100 % higher than that obtained under un-optimized conditions. Therefore mutant 400A15 may represent a biocatalyst of choice for the bioconversion of crude glycerol into value-added metabolites, and a tool for the valorization of this by-product of the biodiesel industry.
在这项工作中，筛选了十八株红色酵母，以在含有甘油的培养基上生产类胡萝卜素。其中，产β-胡萝卜素能力最高的一株粘红酵母（Rhodotorula glutinis）C2.5t1 菌株经紫外线诱变后，筛选到一株突变株 400A15，其β-胡萝卜素产量比出发菌株提高了 280%。对突变株 400A15 进行中心复合设计以优化类胡萝卜素和生物量的生产。所得二次多项式方程的回归分析（R²分别为 0.87 和 0.94，分别用于类胡萝卜素和生物量）表明，这些模型在预测基于粗甘油、酵母提取物和蛋白胨浓度的类胡萝卜素和生物量生产方面是可靠和显著的（P < 0.0001）。根据优化的生长条件，总类胡萝卜素的产量达到 14.07 ± 1.45 mg/L，与最大预测值（14.64 ± 1.57 mg/L）无统计学差异（P < 0.05），比未优化条件下的产量高约 100%。因此，突变株 400A15 可能代表了将粗甘油转化为高附加值代谢物的生物转化过程中的一种生物催化剂，也是利用生物柴油工业副产物的一种工具。
