Centre for Solid Waste Bioprocessing, School of Civil Engineering, School of Chemical Engineering, The University of Queensland, Brisbane 4072, Australia.
Biology Department, San Diego State University, San Diego, CA 92182-4614, United States.
Bioresour Technol. 2016 Sep;215:314-323. doi: 10.1016/j.biortech.2016.04.099. Epub 2016 Apr 22.
Methane, a carbon source for methanotrophic bacteria, is the principal component of natural gas and is produced during anaerobic digestion of organic matter (biogas). Methanotrophs are a viable source of single cell protein (feed supplement) and can produce various products, since they accumulate osmolytes (e.g. ectoine, sucrose), phospholipids (potential biofuels) and biopolymers (polyhydroxybutyrate, glycogen), among others. Other cell components, such as surface layers, metal chelating proteins (methanobactin), enzymes (methane monooxygenase) or heterologous proteins hold promise as future products. Here, scenarios are presented where ectoine, polyhydroxybutyrate or protein G are synthesised as the primary product, in conjunction with a variety of ancillary products that could enhance process viability. Single or dual-stage processes and volumetric requirements for bioreactors are discussed, in terms of an annual biomass output of 1000 tonnesyear(-1). Product yields are discussed in relation to methane and oxygen consumption and organic waste generation.
甲烷是甲烷营养菌的碳源，是天然气的主要成分，由有机物（沼气）的厌氧消化产生。产甲烷菌是单细胞蛋白（饲料补充剂）的可行来源，并且由于它们积累渗透物（例如，四氢嘧啶，蔗糖）、磷脂（潜在的生物燃料）和生物聚合物（聚羟基丁酸酯，糖原）等，可以生产各种产品。其他细胞成分，如表面层、金属螯合蛋白（甲烷菌素）、酶（甲烷单加氧酶）或异源蛋白有望成为未来的产品。在这里，提出了以四氢嘧啶、聚羟基丁酸酯或蛋白 G 作为主要产物，同时结合各种辅助产物的方案，这些产物可以提高工艺的可行性。讨论了单级或两级工艺和生物反应器的体积要求，以 1000 吨/年(-1)的生物质年产量为基准。根据甲烷和氧气的消耗以及有机废物的产生，讨论了产物的产率。
