School of Chemical Engineering and Analytical Science, Manchester University, Oxford Road, Manchester M13 9PL, United Kingdom.
Enzyme Microb Technol. 2012 May 10;50(6-7):337-42. doi: 10.1016/j.enzmictec.2012.03.004. Epub 2012 Mar 22.
Rapeseed meal, a major byproduct of biodiesel production, has been used as a low-cost raw material for the production of a generic microbial feedstock through a consolidated bioconversion process. Various strategies were tested for the production of a novel fermentation medium, rich in free amino nitrogen (FAN): commercial enzymes (CEs) (2.7 mg g⁻¹ dry meal), liquid state fungal pre-treatment (LSF) using Aspergillus oryzae (4.6 mg g⁻¹), liquid state fungal pre-treatment followed by fungal autolysis (LSFA) (9.13 mg g⁻¹), liquid state pre-treatment using fungal enzymatic broth (EB) (2.1 mg g⁻¹), but the best strategy was a solid state fungal pre-treatment followed by fungal autolysis (34.5 mg g⁻¹). The bioavailability of the nitrogen sources in the novel medium was confirmed in fed-batch bioreactor studies, in which 82.3g dry cell L⁻¹ of the oleaginous yeast Rhodosporidium toruloides Y4 was obtained with a lipid content of 48%. The dry cell weight obtained was higher than that obtained using conventional yeast extract, due to a higher total nitrogen content in the novel biomedium. The fatty acids obtained from the microbial oil were similar to those derived from rapeseed oil.
菜粕是生物柴油生产的主要副产物，已被用作通过综合生物转化过程生产通用微生物原料的低成本原料。为生产富含游离氨基酸氮（FAN）的新型发酵培养基，测试了各种策略：商业酶（CE）（2.7mg g⁻¹干粕）、米曲霉液体真菌预处理（LSF）（4.6mg g⁻¹）、液体真菌预处理后真菌自溶（LSFA）（9.13mg g⁻¹）、真菌酶液预处理（EB）（2.1mg g⁻¹），但最佳策略是固体真菌预处理后真菌自溶（34.5mg g⁻¹）。在分批补料生物反应器研究中证实了新型培养基中氮源的生物利用度，在该研究中，产油酵母 Rhodosporidium toruloides Y4 获得了 82.3g 干细胞 L⁻¹，脂肪含量为 48%。由于新型生物医学培养基中的总氮含量较高，因此获得的干细胞重量高于使用常规酵母提取物获得的干细胞重量。从微生物油中获得的脂肪酸与菜籽油衍生的脂肪酸相似。
