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[Display omitted] • Establishment of the first whole-genome CRISPRi library in Y. lipolytica. • Discovery of 14 novel gene targets for improving furfural and acetic tolerance. • Tolerance to the highest known acetic acid content (0.35%, v/v) in Y. lipolytica. • Tolerance mechanism entails enhanced cell division and decreased ROS level. • Tolerance to dual inhibitors during co-utilization of glucose and xylose. Abundant renewable resource lignocellulosic biomass possesses tremendous potential for green biomanufacturing, while its efficient utilization by Yarrowia lipolytica , an attractive biochemical production host, is restricted since the presence of inhibitors furfural and acetic acid in lignocellulosic hydrolysate. Given deficient understanding of inherent interactions between inhibitors and cellular metabolism, sufficiently mining relevant genes is necessary. Herein, 14 novel gene targets were discovered using clustered regularly interspaced short palindromic repeats interference library in Y. lipolytica , achieving tolerance to 0.35 % (v/v) acetic acid (the highest concentration reported in Y. lipolytica), 4.8 mM furfural, or a combination of 2.4 mM furfural and 0.15 % (v/v) acetic acid. The tolerance mechanism might involve improvement of cell division and decrease of reactive oxygen species level. Transcriptional repression of effective gene targets still enabled tolerance when xylose was a carbon source. This work forms a robust foundation for improving microbial tolerance to lignocellulose-derived inhibitors and revealing underlying mechanism. [ABSTRACT FROM AUTHOR]

• A kinetic framework was provided for biomass compounds released in subW. • Secondary char was formed by increasing T from sugar soluble degradation products. • Maillard reactions between sugars and amino acids in subW led to faster reaction loss. • Dehydration products formation was retarded in sugar + amino acid systems. • Higher relative reactivity in Maillard reactions was observed for xylose over glucose. A systematic kinetic study was conducted in subcritical water medium in the temperature range from 150 to 200 °C for pure glucose, xylose, proline and aspartic acid as well as binary mixtures of sugars + amino acids to understand the reaction kinetics and interactions among biomass components and to discern the influence of Maillard reaction (MR) on the overall reaction kinetics. The main degradation products identified for glucose and xylose were the respective dehydration products, hydroxymethyl furfural and furfural, yielding an increasing solid residue with temperature (15.9 wt% at 200 °C) with an augmented heating value. The degradation of sugars and amino acids in binary systems was faster compared to pure compounds due to MR and the production of dehydration products was delayed when considering total sugar conversion. Higher relative reactivity in MR was observed for xylose over glucose showing also higher antioxidant activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A core–shell catalyst mZSM-5@SO 4 2-/mSiO 2 composed of mZSM-5 core and SO 4 2-/mSiO 2 shell was prepared by the soft template method. • The proximity and hierarchy of acidic sites within the core–shell catalyst were constructed to regulate the transport of key intermediates. • The acid ratio was adjusted by introducing the Brønsted acid sites directly into the shell while the core active sites remained unchanged. • The reaction path and mechanism of core–shell catalyst in the preparation of furfural from xylose were revealed. A core–shell catalyst mZSM-5@SO 4 2-/mSiO 2 composed of mZSM-5 core and SO 4 2-/mSiO 2 shell was prepared by the soft template method. Core-shell structure could promote the building of Brønsted -Lewis (B-L) acids interface and significantly improve the synergistic effect of B-L. In this paper, the Brønsted/Lewis (B/L) of mZSM-5@SO 4 2-/mSiO 2 was targeted regulating by innovatively introducing Brønsted acid (BA) sites into the shell. The optimal mZSM-5@SO 4 2-/mSiO 2 catalyst (B/L = 0.142) could achieve 72.1 % furfural yield at 140 ℃ for 1 h. In addition, 70.2 % furfural yield could be obtained after the catalyst was recycled and regenerated for 5 times. Combining In-situ IR and 13C NMR, the reaction path was revealed in detail: xylose was first isomerized to xylulose and then dehydrated to furfural. This paper provides a research idea for the directional regulation of dual active sites of cascade reaction catalysts. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefication of biomass to produce high-quality chemicals and liquid fuels is considered as a renewable and sustainable technology. Herein, a one-step hydrothermal method was used to prepare microcrystalline cellulose supported carbon-based catalyst PTA-BC with the activation factor of phosphotungstic acid. It was demonstrated by Py-FTIR, NH 3 -TPD and XPS that PTA-BC is not only rich in functional groups but also contains Brønsted acid sites (hydroxyl groups) and Lewis acid sites (C C, carboxyl groups). After experimental optimization, the optimum yield of furfural obtained from xylose catalyzed by PTA-BC was 81.02% at the reaction temperature of 180 °C and the reaction time of 20 min. The results show that PTA-BC contains –COOH, –OH and C C as catalytic sites and that the synergistic effect of these functional groups. The nature of the reaction solvent, appropriate reaction temperature and residence time are the main reasons for the good catalytic performance. This work provides a promising way for the synthesis of solid acid catalyst, which has a wide application prospect for the production of furfural. [Display omitted] • Solid acid catalyst was prepared by one step hydrothermal method. • GVL/water solvent green system had an excellent yield of furfural. • The optimum reaction condition of xylose conversion to furfural was obtained. • The reaction mechanism of xylose to furfural was revealed. [ABSTRACT FROM AUTHOR]

• Semi-continuous subcritical hydrolysis of orange wastes to obtaining fermentable sugars. • Yields for platform chemicals (organic acids, furfural, and HMF) are also addressed. • Effects of biomass pretreatment (extraction by soxhlet e supercritical CO 2) were discussed. • 5.3 g/100 g orange peel of hydrolyzed solution was obtained at 180 °C and 15 MPa. • Also, 4.3 g/100 g orange bagasse of hydrolyzed solution was obtained at 200 °C and 20 MPa. Results for the obtaining of fermentable sugars (FSs) and platform chemicals (PCs) from the subcritical hydrolysis of orange wastes (peel and bagasse) are presented. Unlike what is typically reported in similar studies involving lignocellulosic biomasses, the hydrolysis process was performed in a semi-continuous configuration, which allowed the examination of how temperature (180 to 220 °C) and pressure (15 to 25 MPa) influenced the compounds' kinetic profile. Furthermore, studies have been found that evaluated these points for such biomasses. The best yields of hydrolyzed solution were obtained for biomasses pretreated by soxhlet with hydrolysis conducted at 180 °C and 15 MPa (orange peel, OP) and 200 °C and 20 MPa (orange bagasse, OB), yielding 5.31 and 4.26 g (100 g biomass)−1, respectively. Among the FSs, xylose was the monosaccharide predominantly obtained for both biomasses: 21.12 g L −1 for OP pretreated with SCO 2 (hydrolysis at 180 °C and 15 MPa); and 24.45 g L −1 for untreated OB (hydrolysis at 220 °C and 25 MPa). Regarding the PCs, furfural was the main compound obtained for both biomasses: 10.86 g L −1 for untreated OP and 7.33 g L −1 for OB pretreated with SCO 2 , with both hydrolysis conducted at 220 °C and 25 MPa. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • 1,4-Dioxane works as an ingenious and practical solvent in converting C5 and C6 sugars to furfural. • The synergistic action of Hβ zeolite and 1,4-dioxane/H 2 O system promotes furfural production. • Glucose-to-furfural through 3-deoxyglucose should be more favorable than that via fructose. • One-pot catalytic conversion of glucose and xylose mixtures gains a furfural yield as high as 63%. • The activation energy barrier for furfural production is higher from glucose compared to xylose. The simultaneous valorization of biomass-based C5 and C6 sugars to furfural, a versatile intermediate, is of great significance to fully utilize biomass components. Inability to effectively transform C6 sugars remains a major barrier toward this challenging goal. We herein report the 1,4-dioxane-mediated solvent system with Hβ zeolite catalyst for the transformation of glucose giving high yield to furfural (57%). The maintenance of intrinsic balanced Lewis and Brønsted acid sites from Hβ zeolite that is credited to the positive solvent effect of 1,4-dioxane is highly conductive to the selective C-C bond cleavage of glucose. Also importantly, the introduction of proper amount of H 2 O into the reaction system results in a high formation rate and an improved selectivity toward furfural due to the induction of highly reactive acyclic glucose. Glucose-to-furfural through 3-deoxyglucose should be more favorable than that via fructose. Impressively, the developed protocol can also be adapted to C5 sugars dehydration, and the one-pot conversion of glucose and xylose mixtures gains a furfural yield as high as 63%. The activation energy barrier for furfural production is higher from glucose compared to xylose. This work not only develops a promising protocol for furfural production simultaneously from C5 and C6 sugars but also provides insights into the mechanistic role of the solvent 1,4-dioxane to availably manipulate the acid-catalyzed conversion of C6 sugars. [ABSTRACT FROM AUTHOR]