The Fractionation of Corn Stalk Components by Hydrothermal Treatment Followed by Ultrasonic Ethanol Extraction

Synthetic biology approaches to improve tolerance of inhibitors in lignocellulosic hydrolysates

Increasing attention is being focused on using lignocellulose for valuable products. Microbial decomposition can convert lignocellulose into renewable biofuels and other high-value bioproducts, contributing to sustainable development. However, the presence of inhibitors in lignocellulosic hydrolysates can negatively affect microorganisms during fermentation. Improving microbial tolerance to these hydrolysates is a major focus in metabolic engineering. Traditional detoxification methods increase costs, so there is a need for cheap and efficient cell-based detoxification strategies. Synthetic biology approaches offer several strategies for improving microbial tolerance, including redox balancing, membrane engineering, omics-guided technologies, expression of protectants and transcription factors, irrational engineering, cell flocculation, and other novel technologies. Advances in molecular biology, high-throughput sequencing, and artificial intelligence (AI) allow for precise strain modification and efficient industrial production. Developing AI-based computational models to guide synthetic biology efforts and creating large-scale heterologous libraries with automation and high-throughput technologies will be important for future research.

Ultrasound-Assisted Preparation and Performance Regulation of Electrocatalytic Materials

With the advancement of scientific research, the introduction of external physical methods not only adds extra freedom to the design of electro-catalytical processes for green technologies but also effectively improves the reactivity of materials. Physical methods can adjust the intrinsic activity of materials and modulate the local environment at the solid-liquid interface. In particular, this approach holds great promise in the field of electrocatalysis. Among them, the ultrasonic waves have shown reasonable control over the preparation of materials and the electrocatalytic process. However, the research on coupling ultrasonic waves and electrocatalysis is still early. The understanding of their mechanisms needs to be more comprehensive and deep enough. Firstly, this article extensively discusses the adhibition of the ultrasonic-assisted preparation of metal-based catalysts and their catalytic performance as electrocatalysts. The obtained metal-based catalysts exhibit improved electrocatalytic performances due to their high surface area and more exposed active sites. Additionally, this article also points out some urgent unresolved issues in the synthesis of materials using ultrasonic waves and the regulation of electrocatalytic performance. Lastly, the challenges and opportunities in this field are discussed, providing new insights for improving the catalytic performance of transition metal-based electrocatalysts.

Advances in physicochemical pretreatment strategies for lignocellulose biomass and their effectiveness in bioconversion for biofuel production

The inherent recalcitrance of lignocellulosic biomass is a significant barrier to efficient lignocellulosic biorefinery owing to its complex structure and the presence of inhibitory components, primarily lignin. Efficient biomass pretreatment strategies are crucial for fragmentation of lignocellulosic biocomponents, increasing the surface area and solubility of cellulose fibers, and removing or extracting lignin. Conventional pretreatment methods have several disadvantages, such as high operational costs, equipment corrosion, and the generation of toxic byproducts and effluents. In recent years, many emerging single-step, multi-step, and/or combined physicochemical pretreatment regimes have been developed, which are simpler in operation, more economical, and environmentally friendly. Furthermore, many of these combined physicochemical methods improve biomass bioaccessibility and effectively fractionate ∼96 % of lignocellulosic biocomponents into cellulose, hemicellulose, and lignin, thereby allowing for highly efficient lignocellulose bioconversion. This review critically discusses the emerging physicochemical pretreatment methods for efficient lignocellulose bioconversion for biofuel production to address the global energy crisis.

Inhibitor formation and detoxification during lignocellulose biorefinery: A review

For lignocellulose biorefinery, pretreatment is needed to maximize the cellulose accessibility, frequently generating excess inhibitory substances to decline the efficiency of the subsequent fermentation processes. This mini-review updates the current research efforts to detoxify the adverse impacts of generated inhibitors on the performance of biomass biorefinery. The lignocellulose pretreatment processes are first reviewed. The generation of inhibitors, furans, furfural, phenols, formic acid, and acetic acid, from the lignocellulose, with their action mechanisms, are listed. Then the detoxification processes are reviewed, from which the biological detoxification processes are noted as promising and worth further study. The challenges and prospects for applying biological detoxification in lignocellulose biorefinery are outlined. Integrated studies considering the entire biorefinery should be performed on a case-by-case basis.

Multivariable Analysis Reveals the Key Variables Related to Lignocellulosic Biomass Type and Pretreatment before Enzymolysis

In this study, partial least square (PLS), a multivariable analysis, was used to simultaneously quantitatively evaluate the effects of variables related to three pretreatments (alkaline, hot water and acid) and the biomass properties of poplar, salix and corncob. The results showed that biomass type was the most important variable influencing enzymolysis reducing sugar yield (ERSY). The biomass compositions affected the ERSY more than the pretreatment conditions, among which hemicellulose and lignin played vital roles. The alkaline pretreatment had a more positive effect on the ERSY than the acid and hot water pretreatments, in which alkaline content had more influence than temperature. This work provides a deeper understanding of the material properties and the pretreatment conditions in different complex systems before enzymolysis, which might be a guidance to future study.