Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they acti...Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they activated the desaturation system on the endoplasmic reticulum. Additionally, in M. alpina the ARA exists in several forms, such as triacylglycerol(TAG), and diacylglycerol(DAG). These forms are caused by different acyltransferases and they determine the nutrient value of the microbial oil. However, few works revealed detailed fatty acid distribution among lipid classes, which to some extent impeded the accurate regulation in ARA accumulation. Herein, this paper gives information on the accumulation process of main lipid classes and the changes of fatty acid composition in these lipids during ARA accumulation period in M. alpina. The result demonstrates that TAG was the dominant component of the total lipids, and it is the main form for ARA storage. The ARA enrichment stage occurred during 168–192 h when the amount of total lipids maintained steady. Further analysis indicated that the newly formed ARA-TAG might come from the incorporation and modi fication of saturated and monounsaturated fatty acids in other lipid classes. This work could be helpful for further optimization of ARA-rich TAG production.展开更多
Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl...Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1:1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains is possible. The research provides a new idea for the reuse of Daqu distiller's grains and also provides a new way for the development of microbial oils.展开更多
基金Supported by the National Science Foundation for Distinguished Young Scholars of China(21225626)the National Basic Research Program of China(2011CBA00800)+3 种基金the National Natural Science Foundation of China(21376002,21476111)the Natural Science Foundation of Jiangsu Province(BK20131405)the National High-Tech R&D Program of China(2014AA021703)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they activated the desaturation system on the endoplasmic reticulum. Additionally, in M. alpina the ARA exists in several forms, such as triacylglycerol(TAG), and diacylglycerol(DAG). These forms are caused by different acyltransferases and they determine the nutrient value of the microbial oil. However, few works revealed detailed fatty acid distribution among lipid classes, which to some extent impeded the accurate regulation in ARA accumulation. Herein, this paper gives information on the accumulation process of main lipid classes and the changes of fatty acid composition in these lipids during ARA accumulation period in M. alpina. The result demonstrates that TAG was the dominant component of the total lipids, and it is the main form for ARA storage. The ARA enrichment stage occurred during 168–192 h when the amount of total lipids maintained steady. Further analysis indicated that the newly formed ARA-TAG might come from the incorporation and modi fication of saturated and monounsaturated fatty acids in other lipid classes. This work could be helpful for further optimization of ARA-rich TAG production.
基金Project(10A110) supported by Hunan Provincial Education Department of ChinaProject(2010JT4055) supported by Hunan Provincial Science & Technology Department of China
文摘Abstract: Daqu distiller's grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1:1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller's grains is possible. The research provides a new idea for the reuse of Daqu distiller's grains and also provides a new way for the development of microbial oils.