Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855, Athens, Greece.
Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504, Patras, Greece.
World J Microbiol Biotechnol. 2019 Mar 28;35(4):63. doi: 10.1007/s11274-019-2631-z.
The last years a constantly rising number of publications have appeared in the literature in relation to the production of oils and fats deriving from microbial sources (the "single cell oils"-SCOs). SCOs can be used as precursors for the synthesis of lipid-based biofuels or employed as substitutes of expensive oils rarely found in the plant or animal kingdom. In the present review-article, aspects concerning SCOs (economics, biochemistry, substrates, technology, scale-up), with emphasis on the potential of Mortierella isabellina were presented. Fats and hydrophilic substrates have been used as carbon sources for cultivating Zygomycetes. Among them, wild-type M. isabellina strains have been reported as excellent SCO-producers, with conversion yields on sugar consumed and lipid in DCW values reported comparable to the maximum ones achieved for genetically engineered SCO-producing strains. Lipids produced on glucose contain γ-linolenic acid (GLA), a polyunsaturated fatty acid (PUFA) of high dietary and pharmaceutical importance, though in low concentrations. Nevertheless, due to their abundance in oleic acid, these lipids are perfect precursors for the synthesis of 2nd generation biodiesel, while GLA can be recovered and directed to other usages. Genetic engineering focusing on over-expression of Δ6 and Δ12 desaturases and of C16 elongase may improve the fatty acid composition (viz. increasing the concentration of GLA or other nutritionally important PUFAs) of these lipids.
近年来，文献中出现了越来越多与微生物来源的油脂生产相关的出版物（“单细胞油脂”-SCO）。SCO 可作为合成基于脂质的生物燃料的前体，或用作植物或动物界中很少见的昂贵油脂的替代品。在这篇综述文章中，介绍了 SCO 相关的各个方面（经济学、生物化学、底物、技术、放大），重点介绍了玫绒菌（Mortierella isabellina）的潜力。脂肪和亲水底物被用作培养毛霉的碳源。其中，野生型玫绒菌菌株已被报道为出色的 SCO 生产菌，其糖消耗转化率和 DCW 中脂质的转化率与基因工程 SCO 生产菌达到的最高值相当。在葡萄糖上生产的脂质含有γ-亚麻酸（GLA），这是一种具有高饮食和药用重要性的多不饱和脂肪酸（PUFA），尽管浓度较低。然而，由于其油酸含量丰富，这些脂质是合成第二代生物柴油的理想前体，而 GLA 可以回收并用于其他用途。通过基因工程过表达 Δ6 和 Δ12 去饱和酶和 C16 延伸酶，可以改善这些脂质的脂肪酸组成（例如，增加 GLA 或其他营养重要的 PUFAs 的浓度）。
