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Nicotinamide adenine dinucleotide is a crucial coenzyme in cellular metabolism and is implicated in various diseases. This work introduces an electrochemical bioanalytical method utilizing solution-phase Candida boidinii formate dehydrogenase (CbFDH) for detecting its oxidized form (NAD + ) in human blood plasma samples. The detection mechanism involves the catalytic conversion of NAD + to NADH, facilitated by CbFDH in the presence of formate. This NADH is then quantified by electrochemical measurements at disposable carbon screen-printed electrodes. The reaction is completed within one minute. The assay exhibits a linear response range from 3.74 μM to 2.00 mM, a sensitivity of 8.98 ± 0.18 μA mM -1 , and a limit of detection (3 s b / m ) of 1.12 μM. It demonstrates selectivity against common interferences found in plasma samples, including glucose, urea, creatinine, guanosine 5'-monophosphate, cytidine 5'-monophosphate, flavin adenine dinucleotide, adenosine 5'-triphosphate, and lactate, with interference levels below 5% relative to the unperturbed NAD + signal. Recovery studies showed 98.0-104.4% recoveries, with further validation against a colorimetric alcohol dehydrogenase assay confirming accuracy in plasma samples.

Atherosclerosis, resulting from chronic inflammation of the arterial wall, serves as the underlying cause of multiple major cardiovascular diseases. Current anti-inflammatory therapies often exhibit limited and unsatisfactory efficacy. To address this, we have designed a selenium-doped copper formate (Cuf-Se) nanozyme for the treatment of atherosclerosis, which possesses superoxide dismutase (SOD) and glutathione peroxidase (GPx)-like activities. The Cuf-Se can efficiently scavenge reactive oxygen species (ROS), inhibit cellular senescence, and prevent the formation of foam cells. It acts on macrophages to reduce cellular ROS levels and lipid oxidation, thereby significantly inhibiting inflammation-related processes. Notably, while inhibiting foam cell formation, Cuf-Se also alleviates endothelial cells senescence. After intravenous administration, Cuf-Se effectively inhibits the formation of atherosclerosis in mice through the synergistic effects of antisenescence and antioxidant properties, reducing plaque area by approximately 5-fold. This study provides an effective strategy for the treatment of atherosclerosis.

As an "upstream" process in biorefinery, biomass dismantling can dismantle the natural stable structure of lignocellulosic biomass and separate its three major components. To increase the value of the entire biomass by fully utilizing the three main components (cellulose, lignin, and hemicellulose), this study proposes a two-step decomposition system combining formic acid (FA) pretreatment and ethylene glycol-NaOH (EGA) dismantling, aiming to effectively convert sugarcane bagasse into xylose, fermentable glucose, and high-value lignin. In the first step, FA pretreatment removed 79.85 % of hemicellulose at 140 °C for 90 min with 3 % FA. Based on the first step, further combination of EGA dismantling can achieve a hemicellulose removal rate of 92.05 % and a lignin removal rate of 95.90 %. In addition, the solid residue was hydrolyzed by enzymes, and the glucose conversion rate was close to 83.29 % when the cellulase dosage was 10 FPU/g. In addition, the lignin recovered by this system retained 83.62 % of the natural β-O-4 structure, which has the potential to catalyze the formation of aromatic monomers. In summary, this gentle two-step system simultaneously improves the efficiency of lignocellulose decomposition and produces different value-added products, demonstrating the potential for industrial-scale production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To overcome the climate crisis, various greenhouse gas (GHG) mitigation strategies have been developed, and every effort has been made to achieve carbon neutrality. Given that petroleum-based industries and the transportation sector emit enormous amounts of GHGs, the product spectra of biorefineries should be expanded beyond drop-in biofuels to include more value-added products. This study aimed to construct a CO 2 mitigation system. When CO 2 was used as the sole feedstock, value-added phycocyanin and enantioselective γ-valerolactone (GVL) were produced as follows (i) Galdieria sulphuraria was phototrophically cultured to produce phycocyanin (ii) the residual G. sulphuraria after phycocyanin extraction was used as the feedstock for producing levulinic acid and formic acid and (iii) the engineered hydroxybutyrate dehydrogenase-based chemo-enzymatic reaction converted levulinic acid to (R)-GVL with perfect enantiomeric excess > 99.999 %. The results not only contribute to broadening the product spectrum of CO 2 biorefineries but also provide strategies to achieve carbon neutrality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Under mild conditions, formic acid effectively separates the components of lignocellulose, removing the majority of the hemicellulose and lignin from the cellulose. However, it has not yet been determined if multiple treatments with fresh formic acid may totally remove hemicellulose and lignin. In this study, fresh formic acid was used to repeatedly pretreat the bamboo powder, and the effect of multiple treatments on the physicochemical structure of the bamboo powder was investigated using changes in fractions, enzymatic hydrolysis, hydrophilicity, cellulose crystallinity, and lignin structure. Although the hydrophilicity of the powder rose as the number of treatments increased and the number of β-O-4 links in the lignin decreased, it was found that the bamboo powder still contained 5.4% lignin and 2.5% hemicellulose. The 48 h enzymatic yield increased with the number of treatments, with a 59.3% yield obtained at the fifth cycle. This study can serve as a foundation for further research into the mechanism of the influence of organic solvent pretreatment on lignocellulose structural integrity.

Bone tissue, with its complex structure, often necessitates decalcification of the hard tissue for ex vivo morphological studies. The choice of a suitable decalcification method plays a crucial role in preserving desired features and ensuring compatibility with diverse imaging techniques. The search for a universal decalcification method that is suitable for a range of biophotonic analyses remains an ongoing challenge. In this study, we systematically assessed five standard bone decalcification protocols, encompassing strong mineralic acids (3% and 5% nitric acid), a commercially available formulation of hydrochloric and formic acid), as well as weak organic acids (5% trichloroacetic acid and 8% formic acid), and a chelating agent (25% ethylenediamine-tetraacetic acid) with varying decalcification durations, using mouse long bones as our experimental model. Our imaging analysis panel included classical histological staining (Hematoxylin and Eosin, H&E), immunofluorescence staining, and label-free Raman microspectroscopic imaging. We used cryosections instead of paraffin sections since paraffin interferes with tissue Raman signals. This approach is not as commonly used as it is more prone to handling artifacts, but is the preferred method for subsequent Raman analysis. Decalcification efficacy was evaluated based on various qualitative and some quantitative imaging parameters by 2-3 independent observers. Our systematic approach revealed that the chelating agent, when used for 24 h, optimally preserved bone features and, thus, would be the ideal decalcifying agent for comprehensive subsequent analysis. However, the choice of decalcifier and the ideal decalcification duration may vary depending on the type and thickness of bone, necessitating tailored adjustments to meet specific experimental requirements., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

This study investigates the influence of needleless versus needle-based electrospinning methods on the fiber diameter of polyamide 6 (PA6) nanofibers under comparable conditions, with an emphasis on potential pharmaceutical applications. Additionally, it examines how varying solvent systems impact fiber diameter specifically in needleless electrospinning. In this study, it was found that fibers produced by the needleless method were thicker compared to those produced by the needle-based method, a trend attributable to the specific solution characteristics and parameter settings unique to this study. Notably, a 2 : 1 acetic acid : formic acid solvent mixture yielded the largest fiber diameters among the solvent systems assessed for needleless electrospinning. These results underscore the potential of PA6 nanofibers in pharmaceutical applications, suggesting that further optimization of electrospinning conditions could enhance their suitability. The study also discusses the implications of scale-up production using needleless technology, highlighting its viability for industrial applications over single-needle electrospinning.

An effective removal of lignin could reduce the chromogenic groups of lignin in pulp. Herein, corn stover was pulped via the formic acid to investigate the effects of cooking time and temperature on the crude pulp properties. The strong hydrogen ion action of formic acid helped inhibiting both the re-polymerization of degraded lignin molecules and the subsequent adsorption on fiber. The brightness of the crude pulp could reach 51.5 %ISO with the increased lightness and decreased yellowness. The effective lignin removal reduced the residual lignocellulosic bundles in the crude pulp with the increased cooking temperature and time. The lowest lignin content of 3.5 %, α-cellulose content of 94.0 %, and Kappa number of 9.3 were obtained. Meanwhile, the lignin and monosaccharide content in the black liquor could reach 13.3 % and 28.5 %, respectively. The number-average molecular weight of lignin was as low as 818 g/mol. These were helpful to form the hydrogen bonds between fibers, thus enhancing the tensile and burst index of paper sheets. The tensile, burst and tearing indices of the corresponding crude pulp were 47.5 N·m/g, 1.42 kPa·m 2 /g and 6.53 mN·m 2 /g, respectively. This work provided valuable practical significance for studying the performance of straw pulp by high temperature formic acid cooking., Competing Interests: Declaration of competing interest The authors declare that they have no known competing interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The degradation of haloacetic acids (HAAs) in aqueous environments poses a challenge due to their oxidative resistance. Given that HAAs are highly carcinogenic disinfection byproducts, it is imperative to develop effective degradation methods to reduce their potential health risk. In this study, we found that only 27.2% of 200 μM trichloroacetic acid (TCA) was removed in the UV-activated persulfate (PS) system after 2 h, while complete removal was achieved with the addition of 15 mM formic acid (FA). The main products of TCA degradation were dichloroacetic acid and monochloroacetic acid. Results from free radical quenching experiments and electron paramagnetic resonance spectroscopy analyses indicated that reductive carbon dioxide radical (CO 2 •- ) was the main active species responsible for TCA reduction. Oxidative radicals (i.e., SO 4 •- and • OH) generated from PS activation reacted with FA to form CO 2 •- , efficiently degrading TCA. The effects of PS and FA concentrations, solution pH, anions (e.g., Cl - , SO 4 2- , and HCO 3 - ), and small organic molecules (e.g., methanol, ethanol, and acetic acid) on degradation efficiency were examined. Overall, this study proposes a simple and efficient method to improve the degradation efficiency of HAAs in the UV/PS system and provides new insights into the advanced reduction processes used for water treatments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

A simple analytical workflow is described for gas chromatographic-mass spectrometric (GC-MS)-based chiral profiling of secondary amino acids (AAs) in biological matrices. The sample preparation is carried out directly in aqueous biological sample extracts and involves in situ heptafluorobutyl chloroformate (HFBCF) derivatization-liquid-liquid microextraction of nonpolar products into hexane phase followed by subsequent formation of the corresponding methylamides from the HFB esters by direct treatment with methylamine reagent solution. The (O, N) HFB-butoxycarbonyl-methylamide AA products (HFBOC-MA) are separated on a Chirasil-L-Val capillary column and quantitatively measured by GC-MS operated in selected ion monitoring (SIM) mode. The protocol includes 12 simple pipetting steps and covers the quantitative analysis of 8 L, D pairs of secondary amino acids, including proline, isomeric 3-, 4-hydroxyprolines, pipecolic acid, nipecotic acid, azetidine-2-carboxylic acid, and cis- and trans-5-hydroxy-L-pipecolic acid using 13 C 5 -L-proline as an internal standard. The individual analytical steps are commented on and explained, with emphasis on the chiral GC-MS analysis of secondary amino acids in human urine, serum, and peptide hydrolysate samples., (© 2025. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Microbial electrosynthesis (MES) is a rapidly growing technology at the forefront of sustainable chemistry, leveraging the ability of microorganisms to catalyze electrochemical reactions to synthesize valuable compounds from renewable energy sources. The reduction of CO 2 is a major target application for MES, but research in this area has been stifled, especially with the use of direct electron transfer (DET)-based microbial systems. The major fundamental hurdle that needs to be overcome is the low efficiency of CO 2 reduction largely attributed to minimal microbial access to CO 2 owing to its low solubility in the electrolyte. With their tunable physical properties, ionic liquids present a potential solution to this challenge and have previously shown promise in facilitating efficient CO 2 electroreduction by increasing the CO 2 solubility. However, the use of ionic liquids in MES remains unexplored. In this study, we investigated the role of 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) using Shewanella oneidensis MR-1 as a model DET strain. Electrochemical investigations demonstrated the ability of S. oneidensis MR-1 biocathodes to directly convert CO 2 to formate with a faradaic efficiency of 34.5 ± 26.1%. The addition of [EMIM][Ac] to the system significantly increased cathodic current density and enhanced the faradaic efficiency to 94.5 ± 4.3% while concurrently amplifying the product yield from 34 ± 23 μM to 366 ± 34 μM. These findings demonstrate that ionic liquids can serve as efficient, biocompatible cosolvents for microbial electrochemical reduction of CO 2 to value-added products, holding promise for more robust applications of MES.

Background: Sub/supercritical fluid chromatography is regarded as a greener separation technique due to the use of carbon dioxide as the main component of the mobile phase compared to conventional liquid chromatography techniques. Organic co-solvents are usually added to carbon dioxide to increase elution strength of the mobile phase. Therefore, it is of great importance to test applicability of green co-solvents in separation methods and to include them among commonly used mobile phase components., Results: A comprehensive study of the suitability of green solvent dimethyl carbonate as a co-solvent for enantioseparation in sub/supercritical fluid chromatography was conducted with a set of novel psychoactive substances from various groups. The experiments were performed on polysaccharide-based columns. For successful enantioseparation of these compounds, the presence of basic or mixed mobile phase additives was essential. The obtained results clearly show that dimethyl carbonate is a suitable co-solvent for enantioseparation on polysaccharide-based columns in sub/supercritical fluid chromatography and in some cases surpasses commonly used co-solvents as methanol and propan-2-ol., Significance: The use of more sustainable co-solvents, such as dimethyl carbonate, instead of conventional ones to carbon dioxide presents a greener approach to analytical applications and reduces the overall environmental impact of analytical processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Formic acid is consistently produced and detected in prebiotic chemistry experiments, constituting a precursor of many carboxylic acids and amino acids. Its behavior with exposure to gamma radiation varies with the pH and solution concentration. This work aimed to model different environmental conditions for formic acid under ionizing radiation using a system of coupled differential equations based on chemical kinetics. An ensemble of radiolysis reaction mechanisms was generated for formic acid at pH 1.5 and formate ion at pH 9, both with radiation doses from 0 to 2 kGy. This was also done for systems with both species in equilibrium, using high molar concentrations, long irradiation times, and large irradiation doses (from 0 to 70 kGy). The results show that these systems can be modeled with a high statistical relationship between the computed solutions and the experimental data; furthermore, the synthesis and degradation of the radiolysis products can be followed. Another dimension of the issue of prebiotic environments was explored using ionizing radiation and analyzing the reactions at various pH values (acidic to basic media). These models allow one to gain insights into the behavior of molecules that are difficult to detect or analyze in the laboratory. Additionally, they offer the possibility of studying potential prebiotic environments., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Paredes-Arriaga et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Studies surrounding deamidation have relied on the chromatographic and mass spectrometric differentiation of Asn containing peptides and their isomeric Asp and isoAsp products. The development of mass spectrometry analytical techniques and characterization of isomer specific fragmentation patterns has permitted the investigation of some deamidation species but has struggled to remain effective when applied and on complex samples or in high throughput scenarios. On the other hand, chromatographic separations can provide additional information to facilitate detection of deamidation. In this work the retention characteristics of deamidation products have been reported in reversed-phase separations using formic acid as an ion-pairing modifier. We found three major elution patterns depending on primary and secondary structure of Asn-Gly containing tryptic peptides. Random coil, helical conformations, and N-terminal positioning of Asn usually result in Asn < isoAsp < Asp, isoAsp < Asn < Asp, and Asn < Asp < isoAsp elution order, respectively. These trends, found from the analyses of proteomic samples, were subsequently confirmed via analytical scale UV-HPLC. Additionally, we determined the retention shifts following deamidation for twenty various separation settings used as a first-dimension fractionation for high-throughput proteomic 2D LC-MS/MS analyses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Utilising renewable energy to drive the conversion of carbon dioxide into more valuable products can effectively alleviate the energy crisis and protect the environment while actively responding to the policy of "carbon peaking and carbon neutrality". Additionally, formic acid/formate is one of the most promising and commercially valuable products of the electrocatalytic CO 2 reduction reaction (ECO 2 RR) as well as a nonhazardous material for hydrogen storage. With the continuous progress in the field of electrocatalytic CO 2 reduction to formic acid/formate (ECO 2 RF), various electrocatalysts with excellent performance have been developed. In this paper, first, the reaction mechanism of ECO 2 RF is briefly summarised, and then the recent research progress for various catalysts for ECO 2 RF, including metal-based catalysts, carbon-based material catalysts, metal-organic framework catalysts, covalent organic framework catalysts, and molecular catalysts, is reviewed. Finally, the current challenges and future perspectives of ECO 2 RF are discussed and presented., Competing Interests: Declarations. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Spent coffee grounds (SCG) are the waste byproducts of coffee brewing. While SCG can be valorized to produce functional biopolymers due to their valuable structural components, the lignocellulosic structure of SCG is resistant to degradation because of the tightly bound lignin. Therefore, a pretreatment step is required before pulping with peracetic acid (PAA), an eco-friendlier alternative to traditional pulping methods, to facilitate the extraction of these desired cellulosic materials. Formic acid:acetic acid:deionized water (FA:AA:W = 30:50:20) or 60% (v/v) ethanol pretreatments were applied to SCG to compare the characteristics of the resulting cellulosic materials after PAA pulping. Lignocellulose analysis showed that the lignin content (7.06%) of ethanol pretreated SCG was significantly lower (p < 0.05), and the cellulose content (29.52%) was significantly higher (p < 0.05) than the untreated SCG (15.50% and 11.50%, respectively), indicating that an adequate amount of lignin was removed to obtain the cellulosic materials after the pretreatment process. Morphological and structural changes in the lignin and hemicellulose were observed in all the pretreated SCG, which further confirmed that these components were degraded with pretreatments and pulping. Ethanol pretreated SCG showed the most optimal results based on the greatest lignin decrease seen from its lignocellulose composition, appearance, and structure. This study exemplified a conversion process to extract cellulosic materials from SCG more efficiently to utilize for cellulose-based products and verify its potential to be valorized as a waste byproduct. PRACTICAL APPLICATION: Coffee companies can provide the spent coffee grounds (SCG) they produce to develop cellulose-based materials to make biodegradable packaging products rather than throwing them out or burning them. Using SCG for producing cellulose-based materials can help promote sustainability and reduce food waste worldwide. SCG can be utilized as an alternative source based on their abundance and desired biopolymeric properties, providing innovative solutions to industries and increasing consumer awareness of this cause., (© 2024 Institute of Food Technologists.)

Chitin is a class of biomass second only to cellulose in abundance, and the preparation of platform compounds from chitin holds great promise. Herein, a pretreatment biphasic solvent system and a catalytic two-stage process are combined for the direct synthesis of 5-hydroxymethylfurfural (HMF) from chitin. The first step of the process, i.e., the pretreatment of chitin with a CH 3 OH/CaCl 2 solution, alters the structure of chitin, allowing it to be depolymerized more easily. In the second step of the process, a green and recyclable biphasic catalytic solvent system comprising a formic acid solution and n-butanol is prepared using pretreated chitin (Ca-PC) as the starting reactant, realizing an HMF yield of 47.65 % in 32 min. This HMF yield surpasses that reported in the literature (19.3 %-30 %). The synergistic interaction of Ca 2+ , introduced via formic acid pretreatment, is the key to the catalytic system of chitin, which disrupts the internal hydrogen bonding of chitin and simultaneously improves HMF selectivity. In summary, we have promoted the depolymerization of chitin using a simple and effective pretreatment process, designed a catalytic system with a green recyclable reaction, and effectively improved the yield of HMF directly prepared from chitin., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

One-carbon (C1) feedstocks, such as carbon monoxide (CO), formate (HCO 2 H), methanol (CH 3 OH), and methane (CH 4 ), can be obtained either through stepwise electrochemical reduction of CO 2 with renewable electricity or via processing of organic side streams. These C1 substrates are increasingly investigated in biotechnology as they can contribute to a circular carbon economy. In recent years, noncanonical redox cofactors (NCRCs) emerged as a tool to generate synthetic electron circuits in cell factories to maximize electron transfer within a pathway of interest. Here, we argue that expanding the use of NCRCs in the context of C1-driven bioprocesses will boost product yields and facilitate challenging redox transactions that are typically out of the scope of natural cofactors due to inherent thermodynamic constraints., Competing Interests: Declaration of Competing Interest Nothing declared., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The novel Zn-Cu-Al layered double hydroxide (LDH) encapsulated within a chitosan/glutaraldehyde matrix, designated as LDH@Cs/G@Pd, was synthesized through simplified methodologies for the preparation of aromatic aldehyde derivatives. Formic acid served as the carbon monoxide source and hydrogen donor, while chitosan/glutaraldehyde acted as the linking agent between the substrate and palladium nanoparticles, with Echinophora platyloba extract functioning as the reducing agent for palladium. The characterization of LDH@Cs/G@Pd was conducted using a variety of analytical techniques, including Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, and inductively coupled plasma optical emission spectroscopy (ICP-OES). The results indicate that the catalyst has been successfully synthesized and Showed promising characteristics for its intended application. Afterward, the catalyst was utilized to Synthesize aromatic aldehydes. The catalyst developed in this study demonstrated a synthesis yield of approximately 95 % for aromatic aldehydes, confirming its potential as an effective candidate for industrial applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Derivatives of chitosan-ethyl formate polymers (Chs-EF) show promise as biologically relevant materials. The novelty of this study lies in the innovative use of Chs-EF doped with zinc oxide nanoparticles and beta-cyclodextrin, which significantly enhances the polymers' protective activities against Alternaria early blight disease in Vicia faba by improving both disease resistance and plant health. After doping Chs-EF with zinc oxide nanoparticles (ZnONPs) and inserting it into the beta-cyclodextrin (CD), two products emerged: Chs-EF/ZnONPs and Chs-EF/CD. Using βCD and ZnONPs to modify the Chs-EF polymer improves the optical properties of the generated polymers. Also, the energy gab values of the modified polymers (Chs-EF/ZnONPs and Chs-EF/βCD) were 3.3 and 3.7 eV, respectively, while energy gab value of the Chs-EF polymer was 3.9 eV. In this study, the effects of ZnONPs, chitosan, β-CD, and Chs-EF/ZnONPs on Alternaria solani early blight disease in Vicia faba plants were investigated. The treatments were evaluated based on disease symptoms and a disease index (DI) to assess their ability to protect against Alternaria early blight disease blight. The results show that the modified polymer with ZnONPs and beta-cyclodextrin (β-CD) and the modified polymer with ZnONPs (Chs-EF/ZnO NPs) provided the best protection, with DI values of 25 % and 12.5 %, respectively. Furthermore, it was discovered that the levels of carotenoids, chlorophyll a, and chlorophyll b in the infected plants had dropped by 52.6 %, 69.2 %, and 36.1 %, respectively. Chs-EF/ZnONPs were the most effective treatment, showing significant increases in the contents of chlorophyll a and b in infected plants by 120.8 % and 225.4 %, respectively. The study revealed that Chs-EF/ZnONPs exhibited a 131 % increase in the total phenolic content of plants, peroxidase (POD) activity (110.6 %), and a 347 % increase in polyphenol oxidase (PPO) activity, respectively, compared to healthy plants. Malondialdhyde (MDA) decreased by 50.7 %, 49.7 %, 43.4 %, 36.6 %, 31.7 %, and 7.5 % in response to Chs-EF/ZnONPs, Chs-EF/β-CD, Chs-EF, ZnONPs, Chitosan, and β-CD, respectively. Also, application of Chs-EF/ZnONPs, Chs-EF/β-CD, Chs-EF, ZnONPs, Chitosan, and β-CD reduced the production of H 2 O 2 by 77.5 %, 62.8 %, 62.5 %, 39.6 %, 22 %, and 15.1 %, respectively, compared to infected controls. We recommend considering these substances as promising candidates for agricultural use, as they may effectively serve as control agents against early blight caused by Alternaria solani., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Formic acid (HCOOH) is a promising source of hydrogen energy that can be used to produce hydrogen in a more economical and ecological way. Formic acid is a simple carboxylic acid with a high hydrogen concentration and is generally stable, making it useful as a hydrogen transporter. Catalytic dehydrogenation is usually used to extract hydrogen from formic acid; this process releases hydrogen gas and yields carbon dioxide as a byproduct. Comparing this technology to conventional hydrogen generation methods, there are several benefits, such as the utilization of the formic acid handling infrastructure already in place and the possibility of a simpler integration into different energy systems. Notwithstanding, several obstacles persist, including enhancing the effectiveness of the dehydrogenation procedure and reducing the ecological consequences of the correlated carbon dioxide discharges. Catalysts, reaction conditions, and carbon collection and utilization methodologies are all being researched further. The development of Ru and Cu-based catalysts for the catalytic breakdown of HCOOH into CO 2 and H 2 is the main topic of this account. Herein, the focus is on the kinetic studies of HCOOH dehydrogenation, encompassing mechanistic investigations that consider intermediate studies and DFT calculations., (© 2024 The Chemical Society of Japan and Wiley-VCH GmbH.)

Infections caused by Mycobacterium tuberculosis and nontuberculous mycobacteria represent a significant global threat and medical concern. Therefore, accurate and reliable methods must be employed to identify mycobacteria rapidly. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a technique that compares the cellular protein profiles of unknown isolates with reference mass spectra in a database to identify microorganisms. However, the thick and waxy lipid layer, which is rich in mycolic acids and is present in mycobacterial cells, makes protein extraction challenging. To identify the optimal protocol for correctly identifying bacilli using MALDI-TOF mass spectrometry, this study compared four different cellular protein extraction methods. Four strains of M. bovis BCG were selected as representatives of slow-growing mycobacteria, while three strains of fast-growing mycobacteria were also included: M. peregrinum, M. smegmatis, and M. farcinogenes. The extraction method that proved most effective was the extraction of inactivated cells with chloroform and methanol, which partially delipidates the cells. These cells were then extracted with formic acid, as is standard practice for protein extraction. The advantage of this method is that it allows the parallel analysis of cellular lipids and proteins from a single sample. It is therefore important to optimize mycobacterial protein extraction for MALDI-TOF MS analysis in clinical microbiology laboratories., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

A green protocol to extract chitin from crab shells using water soluble ionic liquids (ILs) is here reported. Compared to conventional multistep acid-base extraction methods, this one-pot procedure achieves pulping of recalcitrant crustacean waste shells by employing ammonium acetate, ammonium formate and hydroxylammonium acetate as water-soluble, low-cost and easy to prepare ILs. An extensive parametric analysis of the pulping process has been carried out with different ILs, different ratios, temperature and time. The optimized protocol provides a high-quality chitin comparable, if not better, to commercial chitin. The best results were obtained at 150 °C with ammonium formate prepared in-situ from aqueous ammonia and formic acid: chitin was isolated in a 17 wt% yield (based on dried crab shells as starting biowaste), a degree of acetylation (DA) > 94 %, a crystallinity index of 39-46 %, a molecular weight up to 6.6 × 10 5  g/mol and a polydispersity of ca 2.0., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Rationale: Stable isotope analysis of growth layer groups (GLGs) in mammal dentin is an increasingly prevalent and noninvasive approach to study animal foraging ecology. However, empirical evidence to support assumed proper methodologies for sampling GLGs is lacking. Here, we examine the effects of intratooth and intertooth variations with respect to targeted GLGs, as well as the effects of common pretreatments (e.g., formic acid and graphite) to enhance GLG visibility, on stable isotope values (δ 13 C and δ 15 N) from dentin., Methods: We measured the δ 13 C and δ 15 N values of killer whale (Orcinus orca) dentin. We used dentin from 37 teeth to compare stable carbon (δ 13 C) and nitrogen (δ 15 N) isotope values from multiple locations within a GLG (intratooth variation), from corresponding GLGs among teeth of an individual (intertooth variation), and from treated and untreated teeth., Results: We observed no significant differences in the δ 13 C or δ 15 N values when sampling a single GLG from multiple locations (intratooth variation) or when comparing the same GLG across duplicate teeth of individuals (intertooth variation). One tooth in a triplicate set showed a significantly different but likely biologically inconsequential δ 13 C value. Lastly, formic acid and graphite highlighting to accentuate GLGs did not significantly influence measured stable isotope values., Conclusions: We validate several previous assumptions in this field of study. First, dentin samples for stable isotope analysis can be sampled from different locations across a GLG. Second, researchers can compare stable isotope values from the same GLGs of different teeth collected from the same individual in most cases, as the δ 13 C and δ 15 N values did not vary with the sampled tooth. Third, a common protocol of formic acid and graphite treatment to enhance GLG visibility does not bias the δ 13 C and δ 15 N values from dentin. We also describe factors to consider and cautions associated with these conclusions., (© 2025 The Author(s). Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd.)

The electrocatalytic reduction of carbon dioxide (CO 2 ER) into formate presents a compelling solution for mitigating dependence on fossil energy and green utilization of CO 2 . Bismuth (Bi) has been gaining recognition as a promising catalyst material for the CO 2 ER to formate. The performance of Bi catalysts (named as Bi-V) can be significantly improved when they possess single metal atom vacancy. However, creating larger-sized metal atom vacancies within Bi catalysts remains a significant challenge. In this work, Bi nanosheets with dual V Bi 0 vacancy (Bi-DV) were synthesized utilizing in situ electrochemical transformation, using BiOBr nanosheets with triple vacancy associates (V Bi ″' V O ·· V Bi ″' , V Bi ″' and V O ·· denote the Bi 3+ and O 2- vacancy, respectively) as a template. The obtained Bi-DV achieved higher CO 2 ER activity than Bi-V, showing Faradaic efficiency for formate production of >92% from -0.9 to -1.2 V RHE in an H-type cell, and the partial current density of formate reached up to 755 mA/cm 2 in a flow cell. The comprehensive characterizations coupled with density functional theory calculations demonstrate that the dual V Bi 0 vacancy on the surface of Bi-DV expedite the reaction kinetics toward CO 2 ER, by reducing the thermodynamic barrier of *OCHO intermediate formation. This research provides critical insights into the potential of large atom vacancies to enhance electrocatalysis performance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry. In iodine-adduct chemical ionization mass spectrometry (CIMS), the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet (VUV) lamp initiated CIMS for on-line gaseous formic and acetic acids analysis. In this work, we present a new CIMS based on VUV lamp, and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode. Acetone was added to the photoionization zone, and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I - , and the addition of acetone reduced the amount of methyl iodide by 2/3. In the chemical ionization zone, a headspace vial containing ultrapure water was added for humidity calibration, and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation (R 2 > 0.95). With humidity calibration, the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88% RH. In this mode, limits of detection of 10 and 50 pptv are obtained for formic and acetic acids, respectively. And the relative standard deviation (RSD) of quantitation stability for 6 days were less than 10.5%. This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus (Qingdao, China). In addition, we developed a simple model based formic acid concentration to assess vehicular emissions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The increasing levels of carbon dioxide (CO 2 ) in the atmosphere, primarily due to the use of fossil fuels, pose a significant threat to the environment and necessitate urgent action to mitigate climate change. Carbon capture and utilization technologies that can convert CO 2 into economically valuable compounds have gained attention as potential solutions. Among these technologies, biocatalytic CO 2 hydrogenation using bacterial whole cells shows promise for the efficient conversion of CO 2 into formate, a valuable chemical compound. Although it was discovered nearly a century ago, comprehensive reviews focusing on the utilization of whole-cell bacteria as the biocatalyst in this area remain relatively limited. Therefore, this review provides an analysis of the progress, strategies, and key findings in this field. It covers the use of living cells, resting cells, or genetically modified bacteria as biocatalysts to convert CO 2 into formate, either naturally or with the integration of electrochemical and protochemical techniques as sources of protons and electrons. By consolidating the current knowledge in this field, this review article aims to serve as a valuable resource for researchers and practitioners interested in understanding the recent progress, challenges, and potential applications of bacterial whole cell catalyzed CO 2 hydrogenation into formate., (© 2024 Wiley-VCH GmbH.)

Peptide separation selectivity was evaluated for hydrophilic interaction liquid chromatography (HILIC) ZIC-HILIC, ZIC-cHILIC, and XBridge Amide sorbents using formic acid as eluent additive (pH 2.7). Sequence-specific retention prediction algorithms were trained using retention datasets of ∼30,000 peptides for each column. Our retention models were able to attain ∼0.98 R 2 -value and yielded retention coefficients that can be probed to understand peptide-stationary phase interaction. Overall, the hydrophilicity for these columns decreased when the mobile phase changed pH from 4.5 to 2.7, when using 0.1 % formic acid in the mobile phase. The acidic residues became protonated, and the resultant hydrophilic interaction is dampened at the lower pH, leaving only the basic residues as the primary hydrophilic interactors. Hence, peptides of increasing charge have higher retention. In this comparison between the three columns, ZIC-HILIC has the highest chromatographic resolution between groups of peptides of different charge. From the position-dependent retention coefficients for ZIC-HILIC at pH 2.7, we found that the amino acids at the terminal positions of the peptide modulate the basicity of the N-terminal amino group or the C-terminal Arg/Lys for tryptic peptides. With respect to the separation orthogonality between HILIC and acidic pH RPLC for two dimensional separations, the orthogonality values were lower at pH 2.7 than operating HILIC at pH 4.5 for the first dimension. We also demonstrate that ZIC-HILIC was able to distinguish citrullinated and deamidated peptides based on predicted retention values., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biodiesel production from Calophyllum inophyllum oil in Indonesia produces significant biomass waste, including seed shells. This study explores the conversion of the seed shell of Calophyllum inophyllum into nanocrystalline cellulose (NCC) via consecutive alkalization, bleaching and hydrolysis using various organic acids. Scanning electron microscopy (SEM) analysis showed a reduction in the diameter of cellulose fibers from 21.7 μm to 9.6 μm after alkalinization and bleaching. The hydrolysis process using several organic acids was optimized to produce thermally stable nanocellulose while maintaining its crystallinity. The diameter of the resulting nanofibrous cellulose was 20.53 nm for citric acid, 21.69 nm for maleic acid, and 22.06 nm for formic acid hydrolysis. In particular, lactic acid-derived NCC (NCC-LA) showed the highest crystallinity of 64.22 % with an average diameter of ~13.69 nm. Optimization of hydrolysis parameters using Response Surface Methodology (RSM) suggested 74.79 % crystallinity could be achieved with 6.01 M lactic acid following 3.46 h of hydrolysis at 91.12 °C., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The present study aims at investigating the application of ultrasound assisted choline chloride (ChCl) - formic acid (FA) deep eutectic solvent (DES) pretreatment of Barley straw. In addition, the efficiency of a wet grinding followed by high intensity ultrasound (HIUS) treatment for production of cellulose nanofibers (CNF) has been evaluated. The DES (using ChCl: FA at 1:9 M ratio) treatment at 45 kHz ultrasound frequency and 3 h of treatment duration resulted in 84.68 ± 1.02 % and 82.96 ± 0.79 % of lignin and hemicellulose solubilisation, respectively. The purification of DES treated solid residue resulted in cellulose with more than 90 % purity. Further, 10 min of wet grinding followed by 40 min of HIUS treatment resulted in more than 80 % nano-fibrillation efficiency. The produced CNF had diameters less than 100 nm in number size distribution and type I cellulose structure. This study confirmed that the developed process offers a sustainable method for producing nanocellulose from agricultural waste., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

The "shell biorefinery," which valorizes the shell waste chitin into fine chemicals, has developed rapidly in recent years. Herein, we present a novel base-free heteropolyacid-catalyzed oxidation method for the transformation of chitin biomass into organic acid. After a series of optimization experiments, a 5.93 % yield of formic acid and 25.09 % yield of acetic acid were achieved in the presence of 0.5 equivalent of Mo-V-P heteropolyacids (H 4 PMo 11 VO 40 ·2H 2 O) and air at 180 °C under hydrothermal conditions for 4 h. Meanwhile, we have demonstrated that the Keggin-type heteropolyacid catalysts are capable of efficiently converting microcrystalline chitin into organic acids. The synthesized heteropolyacids are well characterized with FT-IR, XRD, ICP-AES, and TGA. The possible reaction pathway was speculated accordingly. This method offers several advantages, including readily available raw materials, simple operation, and relatively higher yield., Competing Interests: Declaration of competing interest Hongjun Zang reports financial support was provided by Tianjin science and technology commission (No. 18JCYBJC87200). Hongjun Zang reports a relationship with Tianjin science and technology commission that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

ZIF-67 was grown in situ on carbon cloth (CC) using a simple one-step method. The prepared ZIF-67/CC electrodes exhibited excellent CO 2 reduction reaction (CO 2 RR) performance in a dielectric barrier discharge plasma reactor. The highest concentrations of produced formic acid and formaldehyde were 9.16 and 0.068 mmol L -1 at a reaction time of 1 h, respectively. The high performance is related to the unique high aspect ratio structure and pad-like cavity of ZIF-67, which results not only in an increase in the specific surface area for CO 2 adsorption but also in the hydrophobicity of the electrode. Unexpectedly, the superoxide radical (·O 2 - ) greatly affects the reduction performance of the electrode. In addition, the ZIF-67/CC electrode maintained good CO 2 RR performance in the presence of different pollutants, and the production of formic acid and formaldehyde increased to 10.81 and 0.11 mmol L -1 at 1 h with the addition of 10 mg L -1 phenol. This research provides new directions in the field of plasma catalysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

As an intermediate formed by H 2 SO 4 (SA), formic sulfate anhydride (FSA) has been hypothesized to play a role in the nucleation of atmospheric aerosols. It is the first time that the clusters (SA) x (A) y (W) n and (FSA) x (A) y (W) n (x = 1-2; y = 1-2; n = 0-4) were systematically studied in theory on the structures, thermodynamics, intermolecular interactions, humidity dependence, atmospheric dependence and optical properties. FSA is predicted to be more stronger to promote the clustering with ammonia (A) than SA, suggesting that substituent group enhances nucleation capability of FSA. Whereas, the substituent group does not influence the humidity sensitivity of hydrated clusters. The clusters trend to form small hydrated clusters (n water ≦3). The study on atmospheric dependence indicates that the stability of the clusters depends more on temperature other than pressure. Moreover, FSA shows a stronger ability on reducing atmospheric visibility than A, SA and water molecules. This finding aims to draw attention to FSA about atmospheric nucleation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Laccase is an enzyme known for its eco-friendly uses in environmental cleanup and biotechnology. However, it has limitations such as low stability, high cost, and complex recycling. So, there is a need for laccase mimics that can effectively imitate its properties. Herein, we created copper formate-lysine nanoparticles (Cuf-Lys) that mimic laccase's activity. The developed Cuf-Lys demonstrated remarkable polyphenol oxidase-like activity, stability, and recyclability, making them suitable for the fabrication of efficient colorimetric sensors for the detection of epinephrine. These sensors had a specific response and could accurately measure epinephrine concentrations ranging from 2.5 to 50 μM, with a detection limit as low as 1 μM. Furthermore, the biosensor demonstrated high sensitivity and selectivity when applied to the detection of rutin. The limit of detection for rutin was determined to be 0.16 μM while in the linear concentration range of 0.25 to 150.0 μM. We believe that Cuf-Lys provide a new route for the design of laccase mimics, showing potential applications for biomedical diagnosis and environmental monitoring., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Natural product ring distortion strategies have enabled rapid access to unique libraries of stereochemically complex compounds to explore new chemical space and increase our understanding of biological processes related to human disease. Herein is described the development of a ring-cleavage strategy using the indole alkaloids yohimbine, apovincamine, vinburnine, and reserpine that were reacted with a diversity of chloroformates paired with various alcohol/thiol nucleophiles to enable the rapid synthesis of 47 novel small molecules. Ring cleavage reactions of yohimbine and reserpine produced two diastereomeric products in moderate to excellent yields, whereas apovincamine and vinburnine produced a single diastereomeric product in significantly lower yields. Free energy calculations indicated that diastereoselectivity regarding select ring cleavage reactions from yohimbine and apovincamine is dictated by the geometry and three-dimensional structure of reactive cationic intermediates. These compounds were screened for antiplasmodial activity due to the need for novel antimalarial agents. Reserpine derivative 41 was found to exhibit interesting antiplasmodial activities against Plasmodium falciparum parasites (EC 50 = 0.50 μM against Dd2 cultures), while its diastereomer 40 was found to be three-fold less active (EC 50 = 1.78 μM). Overall, these studies demonstrate that the ring distortion of available indole alkaloids can lead to unique compound collections with re-engineered biological activities for exploring and potentially treating human disease.

The molybdenum- and tungsten-containing formate dehydrogenases from a variety of microorganisms catalyze the reversible interconversion of formate and CO 2 ; several, in fact, function as CO 2 reductases in the reverse direction under physiological conditions. CO 2 reduction catalyzed by these enzymes occurs under mild temperature and pressure rather than the elevated conditions required for current industrial processes. Given the contemporary importance of remediation of atmospheric CO 2 to address global warming, there has been considerable interest in the application of these enzymes in bioreactors. Equally important, understanding the detailed means by which these biological catalysts convert CO 2 to formate, a useful and easily transported feedstock chemical, might also inspire the development of a new generation of highly efficient, biomimetic synthetic catalysts. Here we have examined the ability of the FdsDABG formate dehydrogenase from Cupriavidus necator to catalyze the exchange of solvent oxygen into product CO 2 during the course of formate oxidation under single-turnover conditions. Negligible incorporation of 18 O is observed when the experiment is performed in H 2 18 O, indicating that bicarbonate cannot be the immediate product of the enzyme-catalyzed reaction, as previously concluded. These results, in conjunction with the observation that the reductive half-reaction exhibits mildly acid-catalyzed rather than base-catalyzed chemistry, are consistent with a reaction mechanism involving direct hydride transfer from formate to the enzyme's molybdenum center, directly yielding CO 2 . Our results are inconsistent with any mechanism in which the initial product formed on oxidation of formate is bicarbonate.

Formate dehydrogenase can be utilized as a biocatalyst in the bioelectrocatalysis of converting CO 2 into formic acid. However, its industrial application has been hindered by limited thermal stability. This study successfully obtained a mutant (D533S/E684I) with enhanced thermal stability and catalytic activity through the rational design of flexible regions. The mutant exhibited a half-life ( t 1/2 ) 1.5 times longer than the wild type (WT) at 35 °C, along with a specific enzyme activity 7.46 times higher than that of the WT. Additionally, the catalytic efficiency ( k cat / K m value) of the mutant toward the substrate was 2.72 s -1 ·mM -1 , representing a 19.4-fold increase compared to the WT (0.14 s -1 ·mM -1 ). Formic acid production reached 53.4 mM through bioelectrocatalysis after 10 h, utilizing the mutant as the biocatalyst. Molecular dynamics simulations and structural analysis were employed to investigate the molecular mechanisms behind the enhanced thermal stability and activity. The displacement of a highly flexible region in the mutant may counteract the stability-activity trade-off. This study proposed a method for improving both thermal stability and activity in enzyme evolution.

Nitrous acid (HONO) is crucial in atmospheric chemistry as a precursor to morning peak hydroxyl radicals and significantly affects urban air quality by forming secondary pollutants, yet the mechanisms of its daytime formation is not fully understood. This study investigates the role of formic acid (HCOOH), a prevalent electron and proton donor, in the transformation of nitrogen oxides (NOx) and the formation of HONO on photoactive mineral dust. Exploiting hematite (Fe 2 O 3 ) as an environmental indicator, we demonstrate that HCOOH significantly promotes the photoreduction of NO 2 to HONO, while suppressing nitrate accumulation. This occurs through the formation of a surface ≡Fe-OOCH complex, where sunlight activates the C-H bond to generate and transfer active hydrogen, directly converting NO 2 to HONO. Additionally, HCOOH can trigger the photolysis of nitrates as predeposited on Fe 2 O 3 , further increasing HONO production. These findings show that HCOOH-mediated photochemical reactions on iron minerals may contribute to elevated atmospheric HONO levels, highlighting a crucial pathway with broad effects on atmospheric chemistry and public health.

Formate is an important environmental pollutant, and meanwhile its concentration change is associated with a variety of diseases. Thus, rapid and sensitive detection of formate is critical for the biochemical analysis of complex samples and clinical diagnosis of multiple diseases. Herein, a colorimetric biosensor was constructed based on the cascade catalysis of formate oxidase (FOx) and horseradish peroxidase (HRP). These two enzymes were co-immobilized in Cu 3 (PO 4 ) 2 -based hybrid nanoflower with spatial localization, in which FOx and HRP were located in the shell and core of nanoflower, respectively (FOx@HRP). In this system, FOx could catalyze the oxidation of formate to generate H 2 O 2 , which was then utilized by HRP to oxidize 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid to yield blue product. Ideal linear correlation could be obtained between the absorbance at 420 nm and formate concentration. Meanwhile, FOx@HRP exhibited excellent detection performance with low limit of detection (6 μM), wide linear detection range (10-900 μM), and favorable specificity, stability and reusability. Moreover, it could be applied in the detection of formate in environmental, food and biological samples with high accuracy. Collectively, FOx@HRP provides a useful strategy for the simple and sensitive detection of formate and is potentially to be used in biochemical analysis and clinical diagnosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Synthetic biohybrid systems by coupling artificial system with nature's machinery may offer a disruptive solution to address the global energy crisis. We developed a versatile electroenzymatic pathway for the continuous synthesis of valuable chemicals, facilitated by formate-driven NADH regeneration. Utilizing a bismuth electrocatalyst, we achieved stable CO 2 reduction to formate with approximately 90 % Faraday efficiency at a current density of 150 mA cm -2 . The generated formate acts as a mediator to regenerate NADH, which is then coupled with immobilized redox enzymes-alcohol dehydrogenase (ADH), L-lactate dehydrogenase (LDH), and L-glutamate dehydrogenase (GDH)-to produce targeted chemicals at significant rates and exceptionally high turnover numbers (1.8×10 6 to 3.1×10 6 ). These achievements not only underscore the efficiency of the system but also its practical applicability in industrial settings. By leveraging in situ generated formate, this innovative approach demonstrates the potential of integrating electrocatalysis with enzymatic reactions for sustainable and efficient chemical production on a practical scale., (© 2024 Wiley-VCH GmbH.)

This article employs six organic acids to selectively dissolve Mo, Ni and V from spent catalysts, and the most effective acid is identified. Then, the effects of key leaching parameters, including acid concentration, temperature, and S/L ratio, on metal leaching are systematically explored to determine the leaching mechanism. The results demonstrate that the leaching ability of organic acids followed the order: oxalic acid > citric acid > tartaric acid > malonic acid > acetic acid > formic acid. The leaching process of metals was jointly influenced by acidolysis and complexolysis. Among them, more than 93.07 % of Mo, 86.64 % of V, and 74.21 % of Ni were selectively leached with oxalic acid at the optimum condition: S/l: 1/20, oxalic acid: 1.0 mol/L, temp: 60 °C. From the correlation coefficients, the resulting activation energies, and n values, it was demonstrated that Mo and V followed the Avrami dissolution reaction model, V leaching was controlled by the diffusion mode, and Mo leaching was controlled by a mixed mode of chemical reaction and diffusion. The dissolution behavior of both metals consistently adhered to the linear trend of the Avrami kinetic model under varying S/L ratios and oxalic acid concentrations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The oxidation mechanism of methylglyoxal (CH 3 COCHO) in the aqueous phase plays a crucial role in the formation of secondary organic aerosols (SOA). To date, the investigations of reaction mechanisms of MG in the aqueous phase still needs to be refined, and the oxidation mechanisms of MG in the existence of various oxidants (e.g., H 2 O 2 , O 3, ∙NO 3 , etc.) are in controversy. In this paper, we investigated the hypothesis that small-molecule organic acids are the primary products in cloud water and fog droplets, while large-molecule organic acids and oligomers play crucial roles in wet aerosols. Specifically, the hydration reaction, oxidation mechanism and oligomerization reaction of MG in aqueous phase were investigated on a theoretical basis. It has been indicated that the hydration reaction is a significant initiating reaction of MG in the atmospheric aqueous phase, whose generated hydrated compounds played a critical part in the process of forming oligomers. The aqueous oxidation reaction of MG could form a variety of organic acids, including pyruvic acid, formic acid, acetic acid, and oxalic acid. In the presence of OH radicals, pyruvic acid was the main first-generation production, which undergoes further reactions to form acetic acid, oxalic acid, and mesoxalic acid. Acetic acid was mainly derived from the reaction of OH radicals with pyruvic acid, whereas oxalic and mesoxalic acids were mainly generated by the OH radical reaction for MG and pyruvic acid. Of these, the formation of acetic acid was thermodynamically most favorable. Additionally, the reactions of MG with other oxidants also provided the possible pathways for pyruvic acid production. At 298 K, we calculated the rate constants for the reaction of MGHY with NO 3 , OH, HO 2 radicals, and O 3 to be 4.48 × 10 8 , 2.54 × 10 7 , 1.26 × 10 -2 , and 4.38 × 10 -4  M -1  s -1 , with atmospheric aqueous phase lifetimes (τ) of 4.43, 3.12 × 10 3 , 2.21 × 10 11 , and 3.17 × 10 8  h, respectively. The theoretical results from this work will facilitate the explanation for the MG reaction process in the aqueous phase so as to further correctly estimate the relationship between the aqueous phase chemistry of MG and the formation of SOA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. RIFM staff are employees of the Research Institute for Fragrance Materials, Inc. (RIFM). The Expert Panel receives a small honorarium for time spent reviewing the subject work.

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. RIFM staff are employees of the Research Institute for Fragrance Materials, Inc. (RIFM). The Expert Panel receives a small honorarium for time spent reviewing the subject work.

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. RIFM staff are employees of the Research Institute for Fragrance Materials, Inc. (RIFM). The Expert Panel receives a small honorarium for time spent reviewing the subject work.

Here we report an enzymatic approach to synthesize N -formylneuraminic acid (Neu5Fo) containing sialosides, through a five-enzyme cascade. This method stands as an alternative to traditional chemical syntheses, aiming for precision and efficiency in generating sialosides with a tailored N -formyl group generated directly from formic acid. The newly synthesized Neu5Fo was characterized using various NMR techniques revealing a conformational equilibrium at the amide bond of the formyl group in slow exchange on the NMR time scale with a trans  :  cis ratio of ∼2 : 1. This work not only suggests potential for exploring the biological roles of sialosides but also points to the possibility of developing novel therapeutic agents.

We have recently demonstrated the ability of a C 18 stationary phase with a positively charged surface (PCS-C 18 ) to provide superior chromatographic separation of peptides using mobile phase acidified with a mere 0.01 % formic acid, significantly improving MS sensitivity. Here, we examined three columns packed with different PCS-C 18 phases using the MS-favorable mobile phase acidified with low formic acid concentrations to establish the impact of separation performance and better MS sensitivity on peptide identifications. The surface charge interaction was evaluated using the retention of nitrate. The highest interaction was observed for the AdvanceBio Peptide Plus column. A surface charge-dependent shift in the retention time of peptides was confirmed with a change in formic acid concentration in the mobile phase. The separation performance of the columns with MS-favorable mobile phase acidified with low concentrations of formic acid was evaluated using well-characterized peptides. The loading capacity was assessed using a basic peptide with three lysine residues. Good chromatographic peak shapes and high loading capacity were observed for the Acquity Premier CSH C 18 column, even when using a mobile phase acidified with 0.01 % formic acid. The extent of improvement in peptide identification when using reduced formic acid concentration was evaluated by analyzing the tryptic digest of trastuzumab and tryptic digest of whole bacteria cell lysate. Each column provided improved MS signal intensity and peptide identification when using the mobile phase with 0.01 % formic acid. The ability of the Acquity Premier CSH C 18 column to provide better separation of peptides, even with a reduced formic acid concentration in the mobile phase, boosted MS signal intensity by 65 % and increased the number of identified peptides from the bacterial sample by 19 %. Our study confirms that significant improvement in the proteomic outputs can be achieved without additional costs only by tailoring the chemistry of the stationary phase to the composition of the mobile phase. Our results can help researchers understand the retention mechanism of peptides on the PCS-C 18 stationary phases using low-ionic strength mobile phases and, more importantly, select the best-suited stationary phases for their LC-MS proteomic applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

We have characterized the catalytic cycle of the Helicobacter pylori KatA catalase (HPC). H. pylori is a human and animal pathogen responsible for gastrointestinal infections. Multifrequency (9-285 GHz) EPR spectroscopy was applied to identify the high-valent intermediates (5 ≤ pH ≤ 8.5). The broad (2000 G) 9-GHz EPR spectrum consistent with the [Fe(IV) = O Por •+ ] intermediate was detected, and showed a clear pH dependence on the exchange-coupling of the radical (delocalized over the porphyrin moiety) due to the magnetic interaction with the ferryl iron. In addition, Trp • (for pH ≤ 6) and Tyr • (for 5 ≤ pH ≤ 8.5) species were distinguished by the advantageous resolution of their g-values in the 285-GHz EPR spectrum. The unequivocal identification of the high-valent intermediates in HPC by their distinct EPR spectra allowed us to address their reactivity towards substrates. The stabilization of an [Fe(IV) = O Trp • ] species in HPC, unprecedented in monofunctional catalases and possibly involved in the oxidation of formate to the formyloxyl radical at pH ≤ 6, is reminiscent of intermediates previously identified in the catalytic cycle of bifunctional catalase-peroxidases. The 2e - oxidation of formate by the [Fe(IV) = O Por •+ ] species, both at basic and acidic pH conditions, involving a 1H + /2e - oxidation in a cytochrome P450 peroxygenase-like reaction is proposed. Our findings demonstrate that moonlighting by the H. pylori catalase includes formate oxidation, an enzymatic reaction possibly related to the unique strategy of the neutrophile bacterium for gastric colonization, that is the release of CO 2 to regulate the pH in the acidic environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is extensively employed for the identification of filamentous fungi on MALDI Biotyper (Bruker Daltonics) and Vitek MS (biomerieux), but the performance of fungi identification on new EXS2600 (Zybio) is still unknow. Our study aims to evaluate the new EXS2600 system's (Zybio) ability to rapidly identify filamentous fungi and determine its effect on turnaround time (TAT) in our laboratory., Methods: We tested 117 filamentous fungi using two pretreatment methods: the formic acid sandwich (FA-sandwich) and a commercial mold extraction kit (MEK, Zybio). All isolates were confirmed via sequence analysis. Laboratory data were extracted from our laboratory information system over two 9-month periods: pre-EXS (April to December 2022) and post-EXS (April to December 2023), respectively., Results: The total correct identification (at the species, genus, or complex/group level) rate of fungi was high, FA-sandwich (95.73%, 112/117), followed by MEK (94.02%, 110/117). Excluding 6 isolates not in the database, species-level identification accuracy was 92.79% (103/111) for FA-sandwich and 91.89% (102/111) for MEK; genus-level accuracy was 97.29% (108/111) and 96.39% (107/111), respectively. Both methods attained a 100% correct identification rate for Aspergillus, Lichtheimia, Rhizopus Mucor and Talaromyces species, and were able to differentiate between Fusarium verticillioides and Fusarium proliferatum within the Fusarium fujikuroi species complex. Notably, high confidence was observed in the species-level identification of uncommon fungi such as Trichothecium roseum and Geotrichum candidum. The TAT for all positive cultures decreased from pre EXS2600 to post (108.379 VS 102.438, P < 0.05), and the TAT for tissue decreased most (451.538 VS 222.304, P < 0.001)., Conclusions: The FA-sandwich method is more efficient and accurate for identifying filamentous fungi with EXS2600 than the MEK. Our study firstly evaluated the performance of fungi identification on EXS2600 and showed it is suitable for clinical microbiology laboratories use., (© 2024. The Author(s).)

The mesoporous metal oxide semiconductors exhibit unique chemical and physical characteristics, making them highly desirable for catalysis, electrochemistry, energy conversion, and energy storage applications. Here, we report the facial fabrication of mesoporous gray SnO 2 (MGS) electrocatalysts employing an evaporation-induced co-assembly (EICA) approach, utilizing poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers Pluronic P123 (PEO-PPO-PEO) triblock copolymer as a template for electrochemical CO 2 reduction reaction (eCO 2 RR). By sustaining the co-assembly conditions and utilizing a thermal treatment technique based on carbon, gray mesoporous SnO 2 materials with a high density of active sites and oxygen vacancies can be constructed. The MGS materials were employed in eCO 2 RR in a flow cell type, which exhibits excellent catalytic activity and selectivity toward formate with a high partial current density of -234 mA cm -2 and Faradaic efficiency (FE) of 93.60 % at -1.3 V vs. reversible hydrogen electrode (RHE). Interestingly, the mesoporous SnO 2 with a 1.5 wt% ratio of Sn precursor to P123 surfactant (MS-1.5@350N-400A) electrode exhibits a high level of Faradaic efficiency (FE) of (98%) at a low overpotential of -0.6 V RHE , which is a seldom recorded performance for similar systems. A stable FE of 96 ± 1% was observed in the range of -0.6 to -1.2 V RHE , which is the result of a large surface area (184 m 2 /g) and a high number of active sites and oxygen vacancies within the mesostructured framework., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)