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Utilization of one-carbon chemicals such as CO 2 , formate, and methanol by microorganisms can enable the sustainable production of fuels and chemicals. However, the low conversion efficiency of these chemicals by microorganisms is a major challenge. To address this, we designed a one-carbon strategy that can utilize CO 2 and its derivative formate. Here, a platform yeast strain with improved formate utilization and NAD(P)H production was constructed and evaluated for its ability to produce free fatty acids (FFAs). Based on 13C-marked analysis, the one-carbon assimilation efficiency of the platform strain reached 11.24%. Through continuous optimization, under conditions of glucose feeding the formate utilization rate of the final strain reached 0.48 g/L/h, with the final titer of FFAs reached 10.1 g/L, which represented improvements of 21.8 times and 33.7 times, respectively. As such, the produced FFAs can be easily transformed into biodiesel by combining them with downstream technologies in future research. [Display omitted] [ABSTRACT FROM AUTHOR]

CO 2 is one of the main gases leading to the greenhouse effect. The use of a multi-enzyme biological carbon capture and utilization method can reduce the concentration of CO 2. However, most oxidoreductases require NADH as a coenzyme, which is too expensive to afford for most situation. In this research, NADH was regenerated using photocatalysis and CO 2 was converted to formaldehyde by FateDH and FaldDH gradually. TCPP and ZIF-8 were successfully combined to construct a photocatalytic multi-enzyme cascade biomimetic carbon sequestration system for the first time. TCPP was used as the photocatalyst and ZIF-8 was used as the multi-enzyme immobilized carrier for FateDH and FaldDH. The TCPP content, material dosage, pH of reaction solution and the ratio of the two enzymes were optimized in this study. The results indicated that when reacting under visible light for 3 h, using 1 mg/mL 3% TCPP @ZIF-8 at pH 8.0 PBS condition, it has the highest NADH reduction rate, reaching 75.04%. It was also found that when FateDH: FaldDH = 2:1, the formaldehyde yield can reach up to 7.74 μM. And the formaldehyde conversion rate reached 77.37%. In addition, this composite system retained 52.93% of residual activity after 10 batches of re-use. • A photocatalytic multi-enzyme cascade carbon sequestration system was constructed. • Coupled TCPP and ZIF-8 were used for regeneration of NADH with a yeild of 75.04%. • FateDH and FaldDH were immobilized to produce HCHO from CO 2 with a yeild of 77.37%. • The carbon sequestration system can be reused for 10 times. [ABSTRACT FROM AUTHOR]

Due to the poor biodegradability and toxicity of mineral-based lubricants, the development and application of plant-based biolubricants are increasing. However, low stability and poor low temperature performance restrict plant oils to use as lubricants directly. Hence, the paper tried to find an efficient and green way to modify the plant oil derivate oleic acid and obtained high-performance biolubricants. This study demonstrated that modification of oleic acid through epoxidation combined with ring opening reaction, and further esterification, was an efficient strategy for modifying unsaturated fatty acids for the biolubricant production. Meanwhile, catalytic effects of ionic liquids were compared with other catalysts. The results indicated that ionic liquid [HMIm][PF6] is an efficient catalyst for the ring opening and esterification for the synthesis of biolubricants with different kinds of fatty acids. Modified biolubricants from this research exhibited excellent viscosity index (>116) and low temperature performance (pour point < −48 °C). The results of high frequency reciprocating friction experiments exhibited superior lubrication performance of the lubricant. These findings provide a new green and efficient method for improving plant oils as biolubricants. Image 1 • Green way to produce high-performance biolubricant from oleic acid was developed. • Esterification after epoxide ring-opening is efficient for lubricant production. • Catalytic effects of ionic liquids were compared with other reported catalysts. • Biolubricant from this research exhibited excellent low temperature performance. [ABSTRACT FROM AUTHOR]

Due to the poor biodegradability and toxicity of mineral-based lubricants, the development and application of plant-based biolubricants are increasing. However, low stability and poor low temperature performance restrict plant oils to use as lubricants directly. Hence, the paper tried to find an efficient and green way to modify the plant oil derivate oleic acid and obtained high-performance biolubricants. This study demonstrated that modification of oleic acid through epoxidation combined with ring opening reaction, and further esterification, was an efficient strategy for modifying unsaturated fatty acids for the biolubricant production. Meanwhile, catalytic effects of ionic liquids were compared with other catalysts. The results indicated that ionic liquid [HMIm][PF6] is an efficient catalyst for the ring opening and esterification for the synthesis of biolubricants with different kinds of fatty acids. Modified biolubricants from this research exhibited excellent viscosity index (>116) and low temperature performance (pour point < −48 °C). The results of high frequency reciprocating friction experiments exhibited superior lubrication performance of the lubricant. These findings provide a new green and efficient method for improving plant oils as biolubricants. Image 1 • Green way to produce high-performance biolubricant from oleic acid was developed. • Esterification after epoxide ring-opening is efficient for lubricant production. • Catalytic effects of ionic liquids were compared with other reported catalysts. • Biolubricant from this research exhibited excellent low temperature performance. [ABSTRACT FROM AUTHOR]