Rethinking Cultured Meat (CM) Growth Medium: Can Grassland Plant-Derived Supplements Sustainably Support CM Production?

我们正处于农业的第五个时代的开始。一是数据、精准农业和生物技术的融合。养殖蛋白质/养殖肉类预示着生物创新时代的到来，可以提供与传统蛋白质几乎没有区别的替代营养、美味和高质量的蛋白质。养殖肉类(CM)的研究主要集中在可扩展生产系统的瓶颈，即生物反应器设计、支架、细胞源和基质配方。用于CM细胞的增殖和分化的生长介质对于能够有效地生产最终产品是必不可少的。此外，还应在最终产品的碳足迹中考虑介质的配方，以生产碳中性的替代肉类蛋白。CM培养基由市售基础培养基产品提供，含有葡萄糖、氨基酸(氨基酸，即L-谷氨酰胺)和维生素等能量来源，但还必须补充额外的营养物质，如激素和生长因子等。这些通常是通过补充胎牛血清(FBS)提供的，这取决于对怀孕奶牛的屠宰。为了对全球产生有意义的影响，CM蛋白质生产需要同时具有可伸缩性和环境可持续性，这是细胞农业有限公司实现大规模养殖蛋白质生产的重点。CM生产对环境的影响存在相当大的不确定性；尽管CM对全球变暖的影响将小于最初对牛的影响，但这可能不适用于长期，因为与CM生产相关的主要温室气体二氧化碳不同，与牛生产相关的甲烷(CH4)不会在大气中积累[1]。因此，CM的未来影响将取决于畜牧业中可再生能源发电系统和当前/未来生产系统的可用性[2]。此外，到目前为止，对畜牧业管理的评估往往忽视畜牧业系统提供的多种生态系统服务(例如，旅游提供等社会文化利益)，这限制了结果对政策制定者和实践者的适用性[3]。英国约70%的商业饲料作物是牧草(Loillium/Festuca spp.)和三叶草(Trifolium spp.)从中可以很容易地提取出富含果糖和蛋白质的果汁。在牛和羊中，果糖和蛋白质在瘤胃中代谢，产生挥发性脂肪酸(VFA)和微生物细胞蛋白(MCP)，后者与VFA一起被蛋白质分解为AA以进行营养吸收。VFA和MCP都可以在厌氧消化(AD)的产酸阶段产生，在产生CH4之前，随后的蛋白质分解和下游加工(DSP)可能成为CM生产的媒介。学生将接受生物精炼和草原科学、厌氧发酵、种群动力学、生物信息学和生物技术的跨学科培训，研究蛋白质和碳水化合物生物转化为媒介配方。通过实验工作，将发展特定的细胞培养实验设计、方法学技能和CM生产分析(即细胞培养、生物分析、显微镜)。学生将接受生命周期评价、可持续性指标评估方法和不确定度分析方面的培训。培训将得到AD、细胞生物学、实验统计设计、分析化学和制造设计方面的专业知识的支持。

We are at the beginning of a fifth era of agriculture. One at the convergence of data, precision agriculture and biotechnology. Cultured protein/cultivated meat heralds an age of biological innovations that can provide alternative nutritious, flavourful and high-quality protein that is indistinguishable to the traditional. Cultured Meat (CM) research focusses on scalable production system bottlenecks i.e. bioreactor design, scaffolds, cell source and media formulation. The growth medium used for the proliferation and differentiation of the cells used in CM is essential to be able to produce the final product efficiently. Furthermore, formulation of the medium should also be considered in the carbon footprint of the final product, in order to produce a carbon neutral alternative meat protein. CM media is provided through commercially available base media products, containing an energy source, such as glucose, amino acids (AA, i.e. L-glutamine) and vitamins, but must also be supplemented with additional nutrients such as, hormones and growth factors, amongst others. These are usually provided through foetal bovine serum (FBS) supplementation, dependent on the slaughter of pregnant cows. For meaningful global impact, CM protein production needs be both scalable and environmentally sustainable, which is the focus of Cellular Agriculture Ltd to reach large scale cultured protein production.There is considerable uncertainty over the environmental impacts of CM production; although global warming will be less with CM than with cattle initially, this may not apply in the long term because the methane (CH4) associated with cattle production does not accumulate in the atmosphere, unlike CO2, the main greenhouse gas associated with CM production[1]. Future impacts of CM will therefore depend on the availability of renewable systems of energy generation and current/future production systems in animal agriculture[2]. Moreover, assessments of CM to date have tended to overlook the multiple ecosystem services provided by livestock farming systems (e.g. socio-cultural benefits such as tourism provision), through a single-issue focus, limiting the applicability of the results to policy makers and practitioners alike[3]. Approximately 70% of the UK's commercial forage crops are grasses (Loillium/Festuca spp.) and clover (Trifolium spp.) from which a fructose and protein nutrient rich juice can be readily extracted. In cattle and sheep fructose and protein undergo metabolism in the rumen producing volatile fatty acids (VFA's) and microbial cellular protein (MCP) which undergoes proteolysis to AA for nutritional uptake along with VFAs. Both VFA's and MCP can be produced during the acidogenic phase of anaerobic digestion (AD), prior to production of CH4, and following proteolysis and downstream processing (DSP) could potentially ne a media for CM production.The student will undergo interdisciplinary training in biorefining and grassland science, anaerobic fermentation, population dynamics, bioinformatics and biotechnology to investigate protein and carbohydrate bioconversion to media formulations. Specific cell culture experimental design, methodological skills and analysis for CM production (i.e. cell culturing, biological analysis, microscopy) will be developed through experimental work. The student will be trained in LCA and approaches for sustainability indicator evaluation and uncertainty analysis.The training will be supported by expertise in AD, cell biology, statistical design of experiments, analytical chemistry and manufacturing design.