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To understand the role of microorganisms in nitrogen (N)‐containing compound changes during the processing of Yujiangsuan by autochthonous starter cultures, the GC‐TOF‐MS‐based metabolomics method was adopted to investigate the effects of Weissella cibaria and Lactobacillus plantarum. The results demonstrated that inoculation of autochthonous strains led to differential metabolites, such as fatty acids, organic oxygen compounds, and carboxylic acids on day 4 to day 12 of fermentation. The N‐containing compounds under the inoculated fermentation group showed a faster relative concentration change. Nucleotide metabolism and arginine and proline metabolism exerted an influence on the formation of N‐containing compounds. Apart from that, the effect of W. cibaria and L. plantarum on the hydrolysis of macromolecules was the main factor causing differences in major N‐containing compounds. [ABSTRACT FROM AUTHOR]

Highly active catalysts play an important role in modern catalysis. A novel and efficient ligand benzotriazole‐pyrimidine (BTP) and the corresponding rhodium composite on C3N4 were successfully synthesized. The resulting rhodium composite was fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x‐ray diffraction (XRD), thermogravimetric analysis (TGA), and x‐ray photoelectron spectroscopy (XPS). The obtained composite exhibited good catalytic activity and good recovery performance in the synthesis of quinoxaline from 2‐aminobenzyl alcohol and benzonitrile, and more than 20 quinoxalines were obtained in good yields. Additionally, it also showed that rhodium composite could achieved good catalytic performance in the synthesis of functionalized ketone through borrowing hydrogen strategy. [ABSTRACT FROM AUTHOR]

Koji making comprises multi‐microbial interactions and is an important part of soy sauce production. The aim of this study was to determine interactions and investigate metabolites in koji by ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC‐Q/TOF‐MS). Differential metabolites between groups of single strain (Aspergillus oryzae) and mixed strains (Aspergillus niger and A. oryzae) koji making were screened and identified using an untargeted metabolomics approach to evaluate microbial interaction. A. oryzae was the dominant strain in koji mixed fermentation. Growth of both fungal species occurred rapidly during the initial 24 h of fermentation and then stabilised. Inoculation of A. niger led to changes in the contents of dipeptides, flavonoids, unsaturated fatty acids, carotenoids, phenols and indoles in koji. These differences could be attributed to glycerophospholipid and glycerolipid m4etabolism, as well as to pantothenate and CoA biosynthesis of A. niger. [ABSTRACT FROM AUTHOR]

BACKGROUND Aromatic thioether derivatives exist widely in natural products and have significant applications in modern synthesis and the pharmaceutical industry; for example, 2‐sulfanylphenols and arylthioquinones are important intermediates in the processing of anticancer, antibiotic, antivirus and antimalarial drugs. Direct C─H hydroxylation was considered as one of the efficient methods for the synthesis of these compounds. Homogeneous transition metal catalysts usually were used through a cross‐coupling of halogen‐substituted phenols with thiophenols. However, from the perspectives of sustainable development and easy recovery, it is necessary to develop an efficient and recoverable catalytic system to realize the synthesis of aromatic thioether derivatives with good efficiency and recyclability. RESULTS: The heterogeneous catalyst [Cu(binap)I]2@HT in the present work showed good catalytic activity for the C─H hydroxylation of benzenethiol and phenylboronic acid. The catalytic system was tolerant to various substituents including alkyl, alkoxy, ester, halogen or trifluoromethyl on the phenyl ring of the thiophenols or arylboric acids. In addition to electron‐donating groups, the products with strong electron‐withdrawing groups, such as methyl formylate and trifluoromethyl also were achieved with good yields at 90 °C for 12 h (68% and 66%, respectively). Repeated experiment results showed that the catalyst could be reused at least five times without obvious decrease in catalytic activity. CONCLUSION: A BINAP‐Cu complex supported on hydrotalcite was prepared and used as a heterogeneous catalyst for the C─H activation of thiophenol under mild reaction conditions. Through a cascade C─H hydroxylation and further oxidation process, 2‐Sulfanylphenols and arylthioquinones could be obtained with moderate‐to‐good yields for a series of 2‐(phenylthio)phenol derivatives using the heterogeneous catalyst [Cu(binap)I]2@HT. In addition, this heterogeneous catalyst showed good recylbility. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Escherichia coli ( E. coli ) has become a particular concern due to the increasing incidence of antimicrobial resistance (AMR) observed worldwide. Using machine learning (ML) to predict E. coli AMR is a more efficient method than traditional laboratory testing. However, further improvement in the predictive performance of existing models remains challenging. In this study, we collected 1937 high-quality whole genome sequencing (WGS) data from public databases with an antimicrobial resistance phenotype and modified the existing workflow by adding an attention mechanism to enable the modified workflow to focus more on core single nucleotide polymorphisms (SNPs) that may significantly lead to the development of AMR in E. coli. While comparing the model performance before and after adding the attention mechanism, we also performed a cross-comparison among the published models using random forest (RF), support vector machine (SVM), logistic regression (LR), and convolutional neural network (CNN). Our study demonstrates that the discriminative positional colors of Chaos Game Representation (CGR) images can selectively influence and highlight genome regions without prior knowledge, enhancing prediction accuracy. Furthermore, we developed an online tool (https://github.com/tjiaa/E.coli-ML/tree/main) for assisting clinicians in the rapid prediction of the AMR phenotype of E. coli and accelerating clinical decision-making., Competing Interests: 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., (© 2024 The Authors.)

Copper-catalyzed thiophenol C-H activation is described. Through an initial attempt to conduct C-arylation with arylboronic acid, a rather surprising sequential C-H activation and S-arylation was discovered. Mechanistic investigation revealed the disulfide intermediate as the key component in directing C-H oxidation. The overall reaction proceeded under mild conditions with molecular oxygen as the oxidant. Discovery of disulfide as the directing group provides a potential new direction for catalytic C-H functionalization under mild conditions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)