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In this study, the dissipation and transformation of acetamiprid were investigated during the cowpea pickling process and the toxicity assessment software Ecological Structure Activity Relationship (ECOSAR) and the Toxicity Estimation Software Tool (T.E.S.T.) were used to predict the toxicity of acetamiprid and its transformation products (TPs). The results showed that acetamiprid was rapidly degraded during the pickling process with a degradation rate constant of 0.967 61 and a half-life of (34.95 ± 0.78) d. Four TPs from acetamiprid were found during cowpea pickling process. Among them, the oral lethal doses of TP1 and TP2 in rats were 358.17 and 385.7 mg/kg, respectively, which belonged to the “hazardous” category, and the developmental toxicity of TP1 and TP2 was significantly increased compared with that of acetamiprid. In addition, acetamiprid, TP1, TP2, and TP3 were detected in all real samples. The highest mass concentration of acetamiprid was 473.8 μg/L and the median concentration was 41.1 μg/L. These results reveal the degradation and biotransformation of acetamidine during pickling of cowpea and contribute to a better understanding of the possible health risks of pickling foods.

Simple Summary: Chinese cordyceps is a traditional medicinal fungus, Ophiocordyceps sinensis, and Paecilomyces hepiali are fungi isolated from wild Chinese cordyceps. These three species share similar chemical composition and pharmacological effects. This study utilized untargeted metabolomic technology (LC-MS/MS) to analyze metabolites in three samples. The antioxidant activity of the three species was evaluated using 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability (DPPH•), ferric ion-reducing antioxidant power (FRAP), hydroxyl free radical scavenging capacity (•OH), and superoxide anion radical scavenging capacity (O2•−) to understand the differences in antioxidant activities among them. This study aimed to understand the metabolite differences and antioxidant differences of Chinese cordyceps, P. hepiali, and O. sinensis, and to reveal the roles of the differential metabolites in the antioxidant protection mechanism. Chinese cordyceps (GL) is a traditional medicinal fungus, with Ophiocordyceps sinensis (O. sinensis, BL) and Paecilomyces hepiali (P. hepiali, JSB) being fungi isolated from wild Chinese cordyceps. These three species share similar chemical composition and pharmacological effects. Existing studies have primarily compared the metabolites of Chinese cordyceps and O. sinensis, overlooking the assessment of antioxidant capacity in Chinese cordyceps, P. hepiali, and O. sinensis. In this study, LC-MS/MS was employed to analyze metabolites in GL, JSB, and BL. Utilizing principal component analysis (PCA), supervised orthogonal partial least squares discriminant analysis (OPLS-DA), and hierarchical cluster analysis (HCA), it was observed that the majority of differential metabolites (DMs) primarily accumulated in organic acids and derivatives, lipids and lipid-like molecules, and organoheterocyclic compounds. Antioxidant activity analysis indicated that GL exhibited the higher 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability (DPPH•, scavenging rate is 81.87 ± 0.97%), hydroxyl free radical scavenging capacity (•OH, scavenging rate is 98.10 ± 0.60%), and superoxide anion radical scavenging capacity (O2•−, scavenging rate is 69.74 ± 4.36%), while JSB demonstrated the higher FRAP total antioxidant capacity of 8.26 μmol Trolox/g (p < 0.05). Correlation analysis revealed a positive correlation between DMs (fatty acyls and amino acids) and DPPH•, FRAP, •OH, and O2•− (p < 0.05). Additionally, glycerophospholipid DMs were found to be positively correlated with FRAP (p < 0.05). Through KEGG pathway analysis, it was determined that the accumulation of DMs in pathways such as cutin, suberine and wax biosynthesis has a higher impact on influencing the antioxidant activity of the samples. These results shed light on the antioxidant capacity and metabolic characteristics of Chinese cordyceps and its substitutes and offer valuable insights into how different DMs impact the strength of antioxidant activity, aiding in the advancement and application of Chinese cordyceps and its substitutes. [ABSTRACT FROM AUTHOR]

Uracil-DNA glycosylase (UDG) is a base excision repair (BER) enzyme, which catalyzes the hydrolysis of uracil bases in DNA chains that contain uracil and N-glycosidic bonds of the sugar phosphate backbone. The expression of UDG enzyme is associated with a variety of genetic diseases including cancers. Hence, the identification of UDG activity in cellular processes holds immense importance for clinical investigation and diagnosis. In this study, we employed Cas12a protein and enzyme-assisted cycle amplification technology with a test strip to establish a precise platform for the detection of UDG enzyme. The designed platform enabled amplifying and releasing the target probe by reacting with the UDG enzyme. The amplified target probe can subsequently fuse with crRNA and Cas12a protein, stimulating the activation of the Cas12a protein to cleave the signal probe, ultimately generating a fluorescent signal. This technique showed the ability for evaluating UDG enzyme activity in different cell lysates. In addition, we have designed a detection probe to convert the fluorescence signal into test strip bands that can then be observed with the naked eye. Hence, our tool presented potential in both biomedical research and clinical diagnosis related to DNA repair enzymes. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) are a class of non‐coding, small RNAs that play an important role in diverse biological processes and diseases. By regulating the expression of eukaryotic genes post‐transcriptionally in a sequence‐specific manner, miRNAs are widely used to design synthetic RNA switches. However, most of the RNA switches are often dependent on the corresponding ligand molecules, whose specificity and concentration would affect the efficiency of synthetic RNA circuits. Here, a fused transcriptional repressor Gal4BD‐Rluc based gene‐switch system Gal‐miR for miRNA visualization and gene regulation is described. By placing a luciferase downstream gene under the control of endogenous miRNA machinery, the Gal‐miR system makes the conversion of miRNA‐mediated gene silencing into a ratiometric bioluminescent signal, which quantitatively reflected miRNA‐206 activity during myogenic differentiation. Moreover, it demonstrates that this gene‐switch system can effectively inhibit breast cancer cell viability, migration and invasion under the control of specific miRNAs by replacing the downstream gene with melittin functional gene. The study proposes a powerful modular genetic design for achieving precise control of transgene expression in a miRNA responsive way, as well as visualizing the dynamics of miRNA activity. [ABSTRACT FROM AUTHOR]