Towards sustainable cultured meat production by developing a novel biocatalyst

全球肉类消费量巨大，平均每人每年消费45公斤肉类，肉类占全球食品供应的18%。这一需求导致2018年屠宰800亿只动物，产生3.4亿吨肉类产量。然而，尽管动物源性产品仅占全球食品的17%和蛋白质的40-58%，但动物农业对环境的影响却不成比例。它占据了77%的农业用地，利用了30%的水资源，贡献了12-20%的人为温室气体排放。对肉类消费的担忧超出了对环境的影响。猪流感和禽流感等流行病引发了人们对健康的担忧，而在肉类行业使用抗生素导致细菌对抗生素产生耐药性。人造肉，也被称为实验室培养或细胞培养肉，已经成为解决与传统动物养殖相关的可持续性挑战的潜在解决方案。这个过程包括分离动物细胞，并让它们在生物反应器内的培养基中增殖。这些细胞分化成肉类中发现的特殊细胞类型，成熟的培养肉可以收获、加工，并用于制造各种肉类产品。目前，只有新加坡和美国批准了养殖肉制品的销售，但由于生产成本高和零售价格高，养殖肉制品的供应有限。分析表明，细胞培养基构成了大部分成本，主要是由于更昂贵的成分，如重组蛋白、必需氨基酸和生长因子。研究表明，培养肉具有显著减少能源、土地和水的使用以及温室气体排放的潜力，然而，最近的研究表明，培养肉的排放量可能仍然高于猪肉和家禽，但与牛肉相比排放量要低得多，这主要是由于培养基成分的生产和生物反应器中的能源使用。目前的研究项目的目标是开发一种基于简单细胞（SimCell）的生物催化剂，可以将动物细胞培养中的代谢废物（包括氨和乳酸）转化为那些更昂贵的成分，如必需氨基酸和生长因子。模拟细胞是经过修饰的细菌细胞，它不能自我复制，但可以按照设计的基因电路的指示执行某些功能。然后将SimCells放置在动物细胞培养生物反应器中，将废物转化为饲料，这意味着需要更换的细胞培养基数量较少，从而降低了生产成本和废物量。该项目旨在通过降低成本、提高资源效率和潜在地降低环境影响来提高培养肉生产的可持续性。

The global meat consumption is substantial, with the average person consuming 45 kg of meat per year, and meat comprising 18% of the global food supply. This demand led to the slaughter of 80 billion animals in 2018, resulting in 340 million tons of meat production. However, despite animal-derived products providing only 17% of global food and 40-58% of proteins, animal agriculture has a disproportionate environmental impact. It occupies 77% of agricultural lands, utilizes 30% of water resources, and contributes 12-20% of human-induced greenhouse gas emissions. Concerns about meat consumption extend beyond environmental impacts. Epidemics like swine flu and avian flu have raised health concerns, and the use of antibiotics in the meat industry has led to antibiotic resistance in bacteria.Cultured meat, also known as lab-grown or cell-cultured meat, has emerged as a potential solution to address sustainability challenges associated with traditional animal farming. The process involves isolating animal cells and allowing them to proliferate in a culture medium within a bioreactor. The cells differentiate into specialized cell types found in meat, and the matured cultured meat can be harvested, processed, and used to create various meat-based products. Currently, only Singapore and the US have approved the sale of cultured meat products, but their availability is limited due to high production costs and retail prices. The analysis indicates that the cell culture medium constitutes the majority of the costs, primarily attributed to the more expensive components such as recombinant proteins, essential amino acids, and growth factors.Studies have shown that cultured meat has the potential to significantly reduce energy, land, and water use, as well as greenhouse gas emissions, however, recent research indicates that cultured meat may still have higher emissions than pork and poultry but considerably lower emissions compared to beef, primarily due to the production of the culture medium ingredients and energy use in bioreactors. The current research project's objective is to develop a simple cell (SimCell) -based biocatalyst that can convert metabolic wastes from animal cell culture, including ammonia and lactic acid, into those more expensive components such as essential amino acids and growth factors. SimCells are modified bacteria cells which cannot reproduce themselves but can perform certain functions as instructed by the designed gene circuits. The SimCells will then be placed in the animal cell culture bioreactor to convert the wastes into feed, which means less amount of cell culture medium need to be replaced, leading to reduced production cost and amount of waste. This project aims to enhance the sustainability of cultured meat production by reducing costs, improving resource efficiency, and potentially lowering environmental impacts.