MELK aggravates lung adenocarcinoma by regulating EZH2 ubiquitination and H3K27me3 histone methylation of LATS2.

We tried to elucidate the possible roles of maternal embryonic leucine pull chain kinase (MELK) in lung adenocarcinoma (LUAD) growth and metastasis. Differentially expressed genes in LUAD samples were analysed by the GEPIA database. Clinical tissue samples and cells were collected for MELK, EZH2 and LATS2 expression determination. Co-IP assay was used to verify the interaction between EZH2 and MELK; CHX tracking assay and ubiquitination assay detected the degradation of MELK on EZH2 ubiquitination. ChIP assay detected the enrichment of EZH2 and H3K27me3 on the LATS2 promoter region. LUAD cells were selected for in vitro validation, and the tumorigenic ability of LUAD cells was also observed in a transplantation tumour model of LUAD nude mice. MELK and EZH2 were highly expressed in LUAD samples, while LATS2 was lowly expressed. MELK interacted with EZH2 to inhibit its ubiquitination degradation; EZH2 elevated H3K27me3 modification in the LATS2 promoter to lower LATS2 expression. Silencing MELK or EZH2 or overexpressing LATS2 restrained LUAD cell proliferation and invasion, and facilitated their apoptosis. Silencing MELK or EZH2 or overexpressing LATS2 suppressed tumour formation in nude mice. This study demonstrated that MELK aggravated LUAD by upregulating EZH2 and downregulating LATS2.

Electrochemical reductive removal of trichloroacetic acids by a three-dimensional binderless carbon nanotubes/ CoP/Co foam electrode: Performance and mechanism.

Numerous chlorinated disinfection by-products (DBPs) are produced during the chlorination disinfection of water. Among them, chloroacetic acids (CAAs) are of great concern due to their potential human carcinogenicity. In this study, effective electrocatalytic dechlorination of trichloroacetic acids (TCAA), a typical CAAs, was achieved in the electrochemical system with the three-dimensional (3D) self-supported CoP on cobalt foam modified by carbon nanotubes (CNT/CoP/CF) as the cathode. At a 10 mA cm-2 current density, 74.5% of TCAA (500 µg L-1) was converted into AA within 100 min. In-situ growth of CoP increased the effective electrochemical surface area of the electrode. Electrodeposited CNT promoted electron transfer from the electrode surface to TCAA. Therefore, the production of surface-adsorbed atomic hydrogen (H*) on CNT/CoP/CF was improved, further resulting in excellent electrochemical dechlorination of TCAA. The dechlorination pathway of TCAA proceeded into acetic acids via direct electronic transfer and H*-mediated reduction on CNT/CoP/CF electrode. Additionally, the electroreduction efficiency of CNT/CoP/CF for TCAA exceeded 81.22% even after 20 cycles. The highly efficient TCAA reduction performance (96.57%) in actual water revealed the potential applicability of CNT/CoP/CF in the complex water matrix. This study demonstrated that the CNT/CoP/CF is a promising non-noble metal cathode to remove chlorinated DBPs in practice.

Evaluating the role of salinity in enhanced biogas production from two-stage anaerobic digestion of food waste by zero-valent iron.

Salts including NaCl are the most common food flavoring agents so they are often accumulated in food waste (FW) and have potential impact on anaerobic digestion (AD) of FW. In this study, the enhanced biogas production from two-stage anaerobic digestion (TSAD) of FW by microscale zero-valent iron (ZVI) under different salinity (3, 6, 9, and 15 g NaCl/L) was evaluated. Under salinity stress, ZVI becomes a continue-release electron donor due to the enhanced corrosion and dissolution effect and the slow-down surface passivation, further improving the performance of TSAD. Experimental results revealed that the biogas production including H2 and CH4 from TSAD with 10 g/L ZVI addition was promoted under salinity stress. The maximum H2 and CH4 yield (303.38 mL H2/g-VS and 253.84 mL CH4/g-VS) were observed at the salinity 9 g NaCl/L. Compared with that of zero salinity, they increased by 40.94% and 318.46%, respectively. Additionally, Sedimentibacter, an exoelectrogen that can participate in the direct interspecies electron transfer, also exhibited the highest relative abundance (34.96%) at the salinity 9 g NaCl/L. These findings obtained in this study might be of great importance for understanding the influence of salinity on the enhanced AD by ZVI.

Significance of circulating tumor cells detection in tumor diagnosis and monitoring.

To detect circulating tumor cells (CTCs) in the peripheral blood of patients with tumor, and to analyze the significance of CTC detection in tumor diagnosis and monitoring. In the present study, peripheral blood was collected from 125 patients with tumor, and CTCs were isolated and identified. Differences in CTC number and subtype detection were analyzed for different tumor diseases and stages. CTCs were detected in 122 of the 125 patients with tumor, with a positive rate of 97.6%. The number of CTCs increases in patients with vascular metastasis. The number of mesenchymal CTCs increases in patients with lymph node or vascular metastasis. The average ratio of epithelial CTCs in each positive sample decreases in the later stages of cancer compared with the earlier stages, while the average ratio of mesenchymal CTCs increases in the later stages of cancer compared with the earlier stages. The results showed that CTCs with mesenchymal phenotypes are closely related to lymph node or vascular metastasis. CTC detection can help with early diagnosis of tumor diseases. Continuous monitoring of changes in CTCs number and subtypes can assist clinical judgment of tumor disease development status and prognosis.

Drug resistance related genes in lung adenocarcinoma predict patient prognosis and influence the tumor microenvironment.

Lung adenocarcinoma (LUAD) is the predominant type of non-small lung cancer (NSCLC) with strong invasive ability and poor prognosis. The drug resistance related genes are potentially associated with prognosis of LUAD. Our research aimed to identify the drug resistance related genes and explore their potential prognostic value in LUAD patients. The data used in this study were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Firstly, we screened drug resistance related genes in LUAD by differential gene analysis, univariate Cox regression and drug sensitivity analyses. Subsequently, we constructed a risk score model using LASSO Cox regression analysis, and verified whether the risk score can predict the survival of LUAD patients independent of other factors. Moreover, we explored the immune infiltration of 22 immune cells between high-risk and low-risk patients. Totally 10 drug-resistance positively related genes (PLEK2, TFAP2A, KIF20A, S100P, GDF15, HSPB8, SASH1, WASF3, LAMA3 and TCN1) were identified in LUAD. The risk score model of LUAD constructed with these 10 genes could reliably predict the prognosis of LUAD patients. 18 pathways were significantly activated in high-risk group compared with low-risk group. In addition, the infiltration proportion of multiple immune cells was significantly different between high-risk and low-risk groups, and the proportion of M1 phagocytes was significantly higher in the high-risk group compared with the low-risk group. The drug resistance related genes (PLEK2, TFAP2A, KIF20A, S100P, GDF15, HSPB8, SASH1, WASF3, LAMA3 and TCN1) could predict the prognosis of LUAD patients. Clarifying the roles and mechanisms of these 10 genes in regulating drug resistance in LUAD will help to improve individualized clinical treatment protocols and predict patient sensitivity to treatment.

Efficient removal of organic contaminants in CuS-mediated solid-liquid-interfacial fenton-like system: Role of bimetallic cycle and sulfur species.

The conventional Fenton-like system (Fe(III)/H2O2) is severely limited by the inferior activity of Fe(III) on H2O2 activation to produce highly active species and the sluggish regeneration rate of Fe(II). This work significantly enhanced the oxidative breakdown of the target organic contaminant bisphenol A (BPA) by Fe(III)/H2O2 by introducing cheap CuS at a low dose of 50 mg/L. The BPA removal (20 mg/L) in CuS/Fe(III)/H2O2 system reached 89.5 % within 30 min under the optimal conditions: CuS dosage 50 mg/L, Fe(III) concentration 0.05 mM, H2O2 concentration 0.5 mM and pH 5.6. Compared to CuS/H2O2 and Fe(III)/H2O2 systems, the reaction constants had a 47- and 12.3-fold enhancement, respectively. Even compared with the conventional Fe(II)/H2O2 system, the kinetic constant also increased more than twice, further confirming the distinctive superiority of constructed system. Element species change analyses showed that Fe(III) in solution was adsorbed onto the CuS surface, and then Fe(III) was rapidly reduced by Cu(I) in the CuS lattice. Combining CuS and Fe(III) (in-situ formed CuS-Fe(III) composite) created a robust co-effect on the activation of H2O2. Also, S(-II) and its derivatives, e.g., Sn2- and S0 (as an electron donor), could quickly reduce Cu(II) to Cu(I) and ultimately oxidize to the harmless product SO42-. Notably, a mere 50 µM of Fe(III) was sufficient to maintain enough regenerated Fe(II) to effectively activate H2O2 in CuS/Fe(III)/H2O2 system. In addition, such a system achieved a broad range of pH applications and was more suitable for real wastewater containing anions and natural organic matter. Scavenging tests, electron paramagnetic resonance (EPR), and probes further verified the critical role of •OH. This work provides a new approach to solving the problems of Fenton systems through a solid-liquid-interfacial system design and exhibits considerable application potential in wastewater decontamination.

Genetic polymorphisms of 19 X-STRs in populations of Hubei Han and Guangxi Zhuang and their comparisons with 13 other Chinese populations.

BACKGROUND: A prerequisite for applying short tandem repeat (STR) kits is obtaining population allele and/or haplotype frequencies and forensic parameters. AIM: Firstly, we aimed to investigate the population data of 19 X-chromosomal STRs (X-STRs) included in the AGCU X19 STR kit in the Han people residing in Hubei Province, Central China, and the Zhuang people residing in the Guangxi Zhuang Autonomous Region of South China. Furthermore, we compared these population data with those for other Chinese populations. SUBJECTS AND METHODS: In total, 509 unrelated Han males and 266 unrelated Zhuang males were genotyped using the AGCU X19 STR kit. Allele frequencies, haplotype frequencies, and forensic parameters were computed, and genetic differences among 15 Chinese populations were analysed. RESULTS: The 19 X-STRs showed a high power of discrimination and high mean chance of exclusion, whether calculated using allele or haplotype frequencies. Major differences were found between Han and Oroqen, Uyghur, Mongolian, Tibetan, Li, and Yi populations. Aberrant biallelic patterns at DXS10159, DXS10134, and DXS10079 and allelic dropouts at DXS10164 were observed. CONCLUSION: The 19 X-STRs were highly polymorphic in the Hubei Han and Guangxi Zhuang populations, and the AGCU X19 STR kit was shown to be suitable for forensic casework.

Reducing Threshold of Ferroelectric Domain Switching in Ultrathin Two-Dimensional CuInP2S6 Ferroelectrics via Electrical-Mechanical Coupling.

Room-temperature out-of-plane two-dimensional ferroelectrics have promising applications in miniaturized non-volatile memory appliances. The feasible manipulation of polarization switching significantly influences the memory performance of ferroelectrics. However, conventional high-voltage-induced polarization switching inevitably generates charge injection or electric breakdown, and large-mechanical-loading-induced polarization switching may damage the structure of ferroelectrics. Hence, decreasing critical voltage/loading for ferroelectric polarization reversal is highly required. Herein, using atomic force microscopy experiments, the ferroelectric domain switching via both electric field and mechanical loading was demonstrated for an ultrathin (∼4.1 nm) CuInP2S6 nanoflake. The relevant threshold voltage/loading for polarization switching was ∼ -5 V/1095 nN, resulting from the electric field and flexoelectric effect, respectively. Finally, the electrical-mechanical coupling was adopted to reduce the threshold voltage/loading of CuInP2S6 significantly. It can be explained by the Landau-Ginzburg-Devonshire double-well model. This effective way for easily tuning the polarization states of CuInP2S6 opens up new prospects for mechanically written and electrically erased memory devices.

3D Co-Doping α-Ni(OH)2 Nanosheets for Ultrastable, High-Rate Ni-Zn Battery.

The α-Ni(OH)2 is regarded as one promising cathode for aqueous nickel-zinc batteries due to its high theoretical capacity of ≈480 mAh g-1 , its practical deployment however suffers from the poor stability in strong alkaline solution, intrinsic low electrical conductivity as well as the retarded ionic diffusion. Herein, a 3D (three dimensional) macroporous α-Ni(OH)2 nanosheets with Co doping is designed through a facile and easily scalable electroless plating combined with electrodeposition strategy. The unique micrometer-sized 3D pores come from Ni substrate and rich voids between Co-doping α-Ni(OH)2 nanosheets can synergistically afford facile, interconnected ionic diffusion channels, sufficient free space for accommodating its volume changes during cycling; meanwhile, the Co-doping can stabilize the structural robustness of the α-Ni(OH)2 in the alkaline electrolyte during cycling. Thus, the 3D α-Ni(OH)2 shows a high capacity of 284 mAh g-1 at 0.5 mA cm-2 with an excellent retention of 78% even at 15 mA cm-2 , and more than 2000 stable cycles at 6 mA cm-2 , as well as the robust cycling upon various flexible batteries. This work provides a simple and efficient pathway to enhance the electrochemical performance of Ni-Zn batteries through improving ionic transport kinetics and stabilizing crystal structure of cathodes.

Electrocatalytic reduction of nitrate by carbon encapsulated Cu-Fe electroactive nanocatalysts on Ni foam.

Electrocatalytic denitrification is an attractive and effective method for complete elimination of nitrate (NO3-). However, its application is limited by the activity and stability of the electrocatalyst. In this work, a novel bimetallic electrode was synthesized, in which N-doped graphitized carbon sealed with Cu and Fe nanoparticles and immobilized them on nickel foam (CuFe NPs@NC/NF) without any chemical binder. The immobilized Cu-Fe nanoparticles not only facilitated the adsorption of the reactant but also enhanced the electron transfer between the cathode and NO3-, thus promoting the electrochemical reduction of NO3-. Therefore, the as-prepared electrode exhibited enhanced electrocatalytic activity for NO3- reduction. The composite electrode with the Cu/Fe molar ratio of 1:2 achieved the highest NO3- removal (79.4 %) and the lowest energy consumption (0.0023 kW h mg-1). Furthermore, the composite electrode had a robust NO3- removal capacity under various conditions. Benefitting from the electrochlorination on the anode, this electrochemical system achieved nitrogen (N2) selectivity of 94.0 %. Moreover, CuFe NPs@NC/NF exhibited good stability after 15 cycles, which should be attributed to the graphitized carbon layer. This study confirmed that CuFe NPs@NC/NF electrode is a promising and inexpensive electrode with long-term stability for electrocatalytic denitrification.

Electroporation-Assisted Surface-Enhanced Raman Detection for Long-Term, Label-Free, and Noninvasive Molecular Profiling of Live Single Cells.

Molecule characterization of live single cells is greatly important in disease diagnoses and personalized treatments. Conventional molecule detection methods, such as mass spectrography, gene sequencing, or immunofluorescence, are usually destructive or labeled and unable to monitor the dynamic change of live cellular molecules. Herein, we propose an electroporation-assisted surface-enhanced Raman scattering (EP-SERS) method using a microchip to implement label-free, noninvasive, and continuous detections of the molecules of live single cells. The microchip containing microelectrodes with nanostructured EP-SERS probes has a multifunction of cell positioning, electroporation, and SERS detection. The EP-SERS method capably detects both the intracellular and extracellular molecules of live single cells without losing cell viability so as to enable long-term monitoring of the molecular pathological process in situ. We detect the molecules of single cells for two breast cancer cell lines with different malignancies (MCF-7 and MDA-MB-231), one liver cancer cell line (Huh-7), and one normal cell line (293T) using the EP-SERS method and classify these cell types to achieve high accuracies of 91.4-98.3% using their SERS spectra. Furthermore, 24 h continuous monitoring of the heterogeneous molecular responses of different cancer cell lines under doxorubicin treatment is successfully implemented using the EP-SERS method. This work provides a long-term, label-free, and biocompatible approach to simultaneously detect intracellular and extracellular molecules of live single cells on a chip, which would facilitate research and applications of cancer diagnoses and personalized treatments.

CircDDX17 enhances coxsackievirus B3 replication through regulating miR-1248/NOTCH receptor 2 axis.

Coxsackievirus B3 (CVB3) was one of the most common pathogens to cause viral myocarditis. Circular RNAs as novel non-coding RNAs with a closed loop molecular structure have been confirmed to be involved in virus infectious diseases, but the function in CVB3 infection was not systematically studied. In this study, we identified that hsa_circ_0063331 (circDDX17) was drastically decreased after CVB3 infection by circRNA microarray. In vivo and in vitro, when cells or mice were infected with CVB3, the expression of circDDX17 was significantly reduced, as demonstrated by quantitative real-time PCR assays. Additionally, circDDX17 enhanced CVB3 replication by downregulating the expression of miR-1248 in HeLa and HL-1 cells, and miR-1248 regulated CVB3 replication through interacting with the gene coding for NOTCH Receptor 2 (NOTCH2), and NOTCH2 could upregulate methyltransferase-like protein 3 (METTL3). Taken together, this study suggested that circDDX17 promoted CVB3 replication and regulated NOTCH2 by targeting miR-1248 as a miRNAs sponge.

Membrane Proteomic Profiling of Soybean Leaf and Root Tissues Uncovers Salt-Stress-Responsive Membrane Proteins.

Cultivated soybean (Glycine max (L.)), the world's most important legume crop, has high-to-moderate salt sensitivity. Being the frontier for sensing and controlling solute transport, membrane proteins could be involved in cell signaling, osmoregulation, and stress-sensing mechanisms, but their roles in abiotic stresses are still largely unknown. By analyzing salt-induced membrane proteomic changes in the roots and leaves of salt-sensitive soybean cultivar (C08) seedlings germinated under NaCl, we detected 972 membrane proteins, with those present in both leaves and roots annotated as receptor kinases, calcium-sensing proteins, abscisic acid receptors, cation and anion channel proteins, proton pumps, amide and peptide transporters, and vesicle transport-related proteins etc. Endocytosis, linoleic acid metabolism, and fatty acid biosynthesis pathway-related proteins were enriched in roots whereas phagosome, spliceosome and soluble NSF attachment protein receptor (SNARE) interaction-related proteins were enriched in leaves. Using label-free quantitation, 129 differentially expressed membrane proteins were found in both tissues upon NaCl treatment. Additionally, the 140 NaCl-induced proteins identified in roots and 57 in leaves are vesicle-, mitochondrial-, and chloroplast-associated membrane proteins and those with functions related to ion transport, protein transport, ATP hydrolysis, protein folding, and receptor kinases, etc. Our proteomic results were verified against corresponding gene expression patterns from published C08 RNA-seq data, demonstrating the importance of solute transport and sensing in salt stress responses.

Computer-Vision-Based Dielectrophoresis Mobility Tracking for Characterization of Single-Cell Biophysical Properties.

Fast and precise measurements of live single-cell biophysical properties is significant in disease diagnosis, cytopathologic analysis, etc. Existing methods still suffer from unsatisfied measurement accuracy and low efficiency. We propose a computer vision method to track cell dielectrophoretic movements on a microchip, enabling efficient and accurate measurement of biophysical parameters of live single cells, including cell radius, cytoplasm conductivity, and cell-specific membrane capacitance, and in situ extraction of cell texture features. We propose a prediction-iteration method to optimize the cell parameter measurement, achieving high accuracy (less than 0.79% error) and high efficiency (less than 30 s). We further propose a hierarchical classifier based on a support vector machine and implement cell classification using acquired cell physical parameters and texture features, achieving high classification accuracies for identifying cell lines from different tissues, tumor and normal cells, different tumor cells, different leukemia cells, and tumor cells with different malignancies. The method is label-free and biocompatible, allowing further live cell studies on a chip, e.g., cell therapy, cell differentiation, etc.

Electrooxidative tricyclic 6-7-6 fused-system domino assembly to allocolchicines by a removable radical strategy.

Natural allocolchicine and analogues derived thereof a tricyclic 6-7-6-system have been found as key scaffold of various biologically relevant molecules. However, the direct preparation of the allocolchicine motif remains difficult to date. Herein, we report on an electrooxidative radical cyclization of biarylynones with various carbon- and heteroatom-centered radical precursors via a sequential radical addition/7-endo-trig/radical cyclization domino reaction. This approach provides a step-economical and strategically novel disconnection for the facile assembly of a wide range of carbocyclic 6-7-6 fused ring systems. Remarkably, the sulfonyl group on the products could be easily removed by photocatalysis at room temperature with high yields.

Achieving high-performance electrocatalytic reduction of nitrate by N-rich carbon-encapsulated Ni-Cu bimetallic nanoparticles supported nickel foam electrode.

The cathode with low-energy consumption and long-term stability is pivotal to achieve the conversion of nitrate (NO3-) to nitrogen (N2) by electrocatalytic denitrification. Herein, a binder-free electrode was synthesized by directly immobilizing N-doped graphitized carbon layer-encapsulated NiCu bimetallic nanoparticles on nickel foam (NF) (NiCu@N-C/NF) and served as the cathode for electrocatalytic NO3- reduction. Morphological characterization indicated that Ni and Cu nanoparticles were encapsulated by the N-doped graphitized carbon layer and well-dispersed on the surface of NF. Compared with monometallic composite cathode (Cu@N-C/NF and Ni@N-C/NF), NiCu@N-C/NF exhibited better NO3- removal performance (98.63 %) and lower energy consumption (0.007 kW·h mmol-1), which should be attributed to its strong adsorption ability to NO3- and excellent electron transfer property. Meanwhile, its electrocatalytic performance could be maintained in wide initial NO3- concentration (1.79-7.14 mM) and solution pH (3-11). With the assistance of electrochlorination, the N2 selectivity of electrochemical system was up to 99.89 % in the presence of 0.028 M Cl-. More importantly, NiCu@N-C/NF electrode displayed an ultra-high stability during ten recycling experiments. This study indicated that the binderless composite cathode NiCu@N-C/NF had great potential in electrocatalytic NO3- removal from wastewater.

Sulfide enhances the Fe(II)/Fe(III) cycle in Fe(III)-peroxymonosulfate system for rapid removal of organic contaminants: Treatment efficiency, kinetics and mechanism.

The activation of peroxymonosulfate (PMS) by Fe(II) or Fe(III) for environmental decontamination is severely limited by the low conversion rate from Fe(III) to Fe(II). Here, we found that this puzzling problem could virtually be solved by introducing trace amounts of S2-. With the addition of 0.2 mM S2-, the bisphenol A (BPA) degradation efficiency and total organic carbon (TOC) removal in PMS/Fe(III) system were improved by 3.8 and 6.0 times, respectively. Meanwhile, the kobs and PMS utilization efficiency also markedly increased by 650% and 160%, respectively. The constructed PMS/Fe(III)/S2- system exhibited a good applicability to a wide pH range (3.2 ~ 9.5) and high resistance to humic acid, Cl- and NO3-. The main reactive oxidant species in PMS/Fe(III)/S2- system were identified by scavenging experiments, electron paramagnetic resonance measurement, chemical probe approach, and 18O isotope-labeling technique. The identification results revealed that FeIVO2+ was the primary reactive oxidant species, while •OH, SO4•-, O2•- and 1O2 were also involved in the degradation of BPA. Finally, the generalizability of PMS/Fe(III)/S2- system was evaluated by varying the target pollutants, oxidants, and reducing S species. The construction of PMS/Fe(III)/S2- system provides some insights into the treatment of organic wastewaters containing S2-, e.g., from refineries and tanneries.

Zirconium-modified biochar as the efficient adsorbent for low-concentration phosphate: performance and mechanism.

Achieving advanced treatment of phosphorus (P) to prevent water eutrophication and meet increasingly stringent wastewater discharge standard is an important goal of water management. In this study, a low-cost, high-efficiency phosphate adsorbent zirconium-modified biochar (ZrBC) was successfully synthesized through co-precipitation method, in which the biochar was prepared from the pyrolysis of peanut shell powder. ZrBC exhibited strong adsorption ability to low-concentration phosphate (< 1 mg·L-1) in water, and the phosphate removal reached 100% at the investigated dosage range (0.1-1.0 mg·L-1). The adsorption process could be described well by pseudo-second-order model and Langmuir isotherm model, indicating that the phosphate adsorption by ZrBC was mainly a chemical adsorption and single-layer adsorption process. The calculated static maximum phosphate adsorption capacity was 58.93 mg·g-1 at 25 °C. The ligand exchange between surface hydroxyl groups and phosphate was the main mechanism for the phosphate adsorption on ZrBC. The presence of coexisting anions except for SO42- had little effect on the phosphate removal. At the column experiment, ZrBC showed superior treatment capacities for simulated secondary effluents and the breakthrough time for 0.5 mg·L-1 effluent phosphate concentration reached 190 h. ZrBC highlights the potential as an effective and environment-friendly adsorbent for the removal of low-concentration phosphate from secondary effluents of municipal wastewater treatment plants (WWTPs).

Xylose recovery and bioethanol production from sugarcane bagasse pretreated by mild two-stage ultrasonic assisted dilute acid.

Pretreatment can improve biomass biodegradability. Here, a novel sugarcane bagasse (SCB) pretreatment process based on two-stage ultrasonic assisted dilute H2SO4 (TUDA) under mild conditions was reported. After optimization, the pretreatment was shown to significantly degrade hemicellulose (92.40%) and remove lignin (57.41%) of SCB, leading to reduction of inhibitors and an ethanol fermentation efficiency of 93.37% by SSCF under cellulase 10 FPU/g SCB and 30% pretreated SCB loading. Physical characterization revealed that two-stage ultrasonic could better disrupt SCB than traditional ultrasonic by amplifying the collapse effect and synergistically promoting lignin removal through dilute H2SO4. Furthermore, xylose was also effectively recovered from pretreatment supernatant by biochar derived from bagasse. This study established a simple and efficient pretreatment process for high value-added recycling of SCB from solid residue to pretreatment liquid.