Abstract:
Acidogenic fermentation of food waste using mixed microbial cultures can produce carboxylates [or volatile fatty acids (VFA)] as high-valued bioproducts via a complex interplay of microorganisms during different stages of this process. However, the present fermentation systems are incapable of reaching the industrially relevant VFA production yields of ≥50 g/L primarly due to the complex process operation, competitive metabolic pathways, and limited understanding of microbial interplays. Recent reports have demonstrated the significant roles played by microbial communities from different phyla, which work together to control the process kinetics of various stages underlying acidogenic fermentation. In order to fully delineate the abundance, structure, and functionality of these microbial communities, next-generation high-throughput meta-omics technologies are required. In this article, we review the potential of metagenomics and metatranscriptomics approaches to enable microbial community engineering. Specifically, a deeper analysis of taxonomic relationships, shifts in microbial communities, and differences in the genetic expression of key pathway enzymes under varying operational and environmental parameters of acidogenic fermentation could lead to the identification of species-level functionalities for both cultivable and non-cultivable microbial fractions. Furthermore, it could also be used for successful gene sequence-guided microbial isolation and consortium development for bioaugmentation to allow VFA production with high concentrations and purity. Such highly controlled and engineered microbial systems could pave the way for tailored and high-yielding VFA synthesis, thereby creating a petrochemically competitive waste-to-value chain and promoting the circular bioeconomy.Research HighlightsMixed microbial mediated acidogenic fermentation of food waste.Metagenomics and metatranscriptomics based microbial community analysis.Omics derived function-associated microbial isolation and consortium engineering.High-valued sustainable carboxylate bio-products, i.e. volatile fatty acids.
摘要:
使用混合微生物培养物进行食物垃圾的产酸发酵可以通过微生物在此过程的不同阶段的复杂相互作用产生羧酸盐[或挥发性脂肪酸(VFA)]作为高价值的生物产品。然而,主要由于复杂的工艺操作,目前的发酵系统无法达到工业相关的VFA产量≥50g/L。竞争性代谢途径,以及对微生物相互作用的有限理解。最近的报道表明,来自不同门的微生物群落发挥了重要作用,它们共同控制产酸发酵的各个阶段的过程动力学。为了充分描绘丰度,结构,以及这些微生物群落的功能,需要下一代高通量的元组学技术。在这篇文章中,我们回顾了宏基因组学和超转录组学方法在实现微生物群落工程方面的潜力。具体来说,对分类关系进行更深入的分析,微生物群落的变化,在不同的产酸发酵操作和环境参数下,关键途径酶的遗传表达差异可能导致可培养和不可培养微生物部分的物种水平功能鉴定。此外,它还可以用于成功的基因序列指导的微生物分离和生物强化的财团开发,以允许高浓度和纯度的VFA生产。这种高度受控和工程化的微生物系统可以为定制的高产VFA合成铺平道路,从而创建一个具有石油化学竞争力的废物价值链,促进循环生物经济。研究重点混合微生物介导的餐厨垃圾产酸发酵。基于宏基因组学和超转录组学的微生物群落分析。组学衍生的功能相关微生物分离和联合体工程。高价值的可持续羧酸盐生物制品,即挥发性脂肪酸。