Toward bioproduction of oxo chemicals from C1 feedstocks using isobutyraldehyde as an example

Abstract

Oxo chemicals are valuable chemicals for synthesizing a wide array of industrial and consumer products. However, producing of oxo chemicals is predominately through the chemical process called hydroformylation, which requires petroleum-sourced materials and generates abundant greenhouse gas. Current concerns on global climate change have renewed the interest in reducing greenhouse gas emissions and recycling the plentiful greenhouse gas. A carbon–neutral manner in this regard is producing oxo chemicals biotechnologically using greenhouse gas as C1 feedstocks. Exemplifying isobutyraldehyde, this review demonstrates the significance of using greenhouse gas for oxo chemicals production. We highlight the current state and the potential of isobutyraldehyde synthesis with a special focus on the in vivo and in vitro scheme of C1-based biomanufacturing. Specifically, perspectives and scenarios toward carbon– and nitrogen–neutral isobutyraldehyde production are proposed. In addition, key challenges and promising approaches for enhancing isobutyraldehyde bioproduction are thoroughly discussed. This study will serve as a reference case in exploring the biotechnological potential and advancing oxo chemicals production derived from C1 feedstocks.

Ligand Hydrogenation during Hydroformylation Catalysis Detected by In Situ High-Pressure Infra-Red Spectroscopic Analysis of a Rhodium/Phospholene-Phosphite Catalyst

“…Whilst the reaction is of interest across several sectors, the largest scale hydroformylation reaction practised is the Rh-catalysed hydroformylation of propene. Whilst linear selective reactions produce n -butanal, needed on a large scale, the formation of iso -butanal is of more recent interest, both as a conceptual challenge to reverse the innate preference of these reactions and since iso -butanal now has a very significant and increasing market [ 33 , 34 , 35 ]. This reaction has been the focus of a long-standing project in our laboratories, and branched selective hydroformylations (and hydroformylation with unusually low n/iso ratios) have been studied quite widely [ 36 ].…”

“…Hydroformylation catalysis continues to attract academic research interest and promote new discoveries in the industry [31][32][33][34]. Whilst the reaction is of interest across several sectors, the largest scale hydroformylation reaction practised is the Rh-catalysed hydroformylation of propene.…”

Strategies for improving the production of bio-based vanillin

“…Knocking out ADH6 successfully decreased the conversion rate of vanillin to vanillyl alcohol by 50% [ 28 ]. It seems to be difficult to completely prevent the product degradation due to the presence and catalytic promiscuity of multiple endogenous alcohol dehydrogenases or aldehyde reductases in model hosts [ 33 ]. In this regard, multiple alcohol dehydrogenase genes including dkgA, dkgB, yeae, yahk, yjgB , and yqhD were simultaneously deleted in E. coli K-12 MG1655 strain, resulting in significantly reduced vanillyl alcohol and a 55-fold increase in vanillin yield [ 34 ].…”

Integrating Carbohydrate and C1 Utilization for Chemicals Production

“…Guo et al proposed a pathway from CO 2 to isobutyraldehyde by combining the carbon-carbon bond forming modules from Cai et al with a glycolysis module to form pyruvate and from pyruvate a third module to isobutyraldehyde, but lacked experimental proof. [34] In this way, isobutanol could be produced exclusively from C1-chemicals, but the key enzyme formolase, which produces dihydroxyacetone from formaldehyde, lacks high activity and specificity for formaldehyde. Large amounts of expensive protein would be required to produce isobutyraldehyde or isobutanol.…”