{"title":"Molecular Insights into Covalent Binding between Anthocyanin C3G and α-Glucosidase: Interaction of Flavylium with Cysteine Thiol","authors":"Yu Long,Tingxin Yu,Jianxia Sun,Jun Hu,Weibin Bai","doi":"10.1021/acs.jafc.6c07262","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c07262","url":null,"abstract":"Dietary anthocyanins have attracted considerable attention for their ability to modulate postprandial glycemia, yet their molecular mechanisms remain unclear. Here, we show that cyanidin-3-O-glucoside (C3G), a major anthocyanin, inhibits α-glucosidase through a cysteine-directed covalent interaction. C3G inhibited yeast α-glucosidase and a mouse intestinal α-glucosidase preparation with IC50 values of 169.7 and 719.1 μM, while time-dependent kinetic analysis yielded apparent kinact/KI values of 1.46 × 10–5 and 3.02 × 10–6 μM–1 min–1. Activity-based protein profiling (ABPP) and cysteine-blocking experiments supported cysteine-dependent probe engagement, with direct covalent probe labeling and reduced labeling after cysteine blockade. Mechanistically, the intrinsic electrophilic flavylium (FAV) scaffold undergoes nucleophilic addition with free thiols to form stable covalent adducts. Covalent docking suggested Cys9 as a candidate residue in mammalian α-glucosidase. Cysteine-directed reactivity provides a chemical basis for the sustained inhibitory effects of C3G. This mechanism reveals a previously underappreciated covalent component of anthocyanin–α-glucosidase interactions.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"4 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaomiao Xu,Tonghui Ma,Lingwei Zhang,Yue Zhang,Jun Yao,Jinsheng Wang,Li Xu,Shuai Zhan,Yaohui Wang
{"title":"Decoupled Adult and Larval Host Preferences in Tephritid Fruit Flies with a Conserved Oviposition Attractant","authors":"Xiaomiao Xu,Tonghui Ma,Lingwei Zhang,Yue Zhang,Jun Yao,Jinsheng Wang,Li Xu,Shuai Zhan,Yaohui Wang","doi":"10.1021/acs.jafc.6c09170","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c09170","url":null,"abstract":"Tephritid fruit flies exhibit considerable variability in host range, yet the chemosensory mechanisms underlying adult host selection and larval performance across species with contrasting dietary breadths remain unclear. Here, we investigated behavioral responses of adults and larvae of four species─Bactrocera dorsalis, B. correcta, Zeugodacus tau, and Z. cucurbitae─to seven fruit and vegetable cues. Adult preferences varied, with guava eliciting the strongest attraction in all species. Larval preferences were weaker and decoupled from adult choices. Comparative transcriptomics of guava-exposed antennae identified OBP19d as the most highly upregulated odorant-binding protein across species. RNAi knockdown of BdOBP19d in B. dorsalis reduced electrophysiological responses to guava volatiles and specifically abolished oviposition preference for 4-Ethylacetophenone. Molecular docking, electrophysiology, and behavioral assays collectively validated this interaction. These results reveal a conserved olfactory module for shared host attraction and identify 4-Ethylacetophenone as a candidate attractant for B. dorsalis females, with potential implications for pest management.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"497 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Susan Genualdi,Sara Lupton,Elsie Peprah,Sami Popol,Manjula Sunkara,Ivan Lenov,Ryan Matsuda,Kimberly Nguyen,Candice Ulmer Holland,Kassidy Castillo Parkman,Robert D. Hurst,Nic Bice,Melissa Chisholm,Lowri DeJager
{"title":"A Harmonized Method for the Analysis of 32 PFAS in Priority Food Matrices for Interagency Regulatory Analysis","authors":"Susan Genualdi,Sara Lupton,Elsie Peprah,Sami Popol,Manjula Sunkara,Ivan Lenov,Ryan Matsuda,Kimberly Nguyen,Candice Ulmer Holland,Kassidy Castillo Parkman,Robert D. Hurst,Nic Bice,Melissa Chisholm,Lowri DeJager","doi":"10.1021/acs.jafc.6c11908","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c11908","url":null,"abstract":"This study represents a collaboration between state and federal agencies to develop a method for 32 per- and polyfluoroalkyl substances (PFAS) in eggs, meat, seafood, milk, and corn snaplage. The method was single-lab-validated with three spiking levels in each matrix. Recoveries were required to meet validation guidelines set in the Association of Official Analytical Chemistry (AOAC) standard method performance requirements (SMPR 2023.003). This method was also implemented in a state lab, and single-lab validation data and incurred residue samples were compared. Matrix effects and interferences are discussed, along with proficiency testing results. Average method detection limits were <10 ng/kg for all PFAS analytes across meat, eggs, milk, and seafood matrices. For PFOS, PFOA, PFHxS, and PFNA, LOQs calculated as the lowest validated level were able to meet the required LOQs as defined in EU 2022/1428 and AOAC SMPR 2023.003.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"11 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Changyu Cao,Yu Wang,Weifeng Ni,Yihao He,Yang Liu,Nan Li,Xinran Li
{"title":"Mitochondrial Dysfunction Triggered by T-2 Toxin-Induced Thioredoxin Reductase 2 (TXNRD2) Depletion and Its Molecular Mechanism","authors":"Changyu Cao,Yu Wang,Weifeng Ni,Yihao He,Yang Liu,Nan Li,Xinran Li","doi":"10.1021/acs.jafc.5c17572","DOIUrl":"https://doi.org/10.1021/acs.jafc.5c17572","url":null,"abstract":"The T-2 toxin is a prevalent trichothecene mycotoxin that threatens food safety and animal health, yet its direct mitochondrial targets remain poorly defined. Using network toxicology and in vitro validation in porcine renal PK15 cells, thioredoxin reductase 2 (TXNRD2) was identified as the most significantly downregulated mitochondrial selenoprotein upon T-2 toxin exposure. Molecular docking and enzymatic assays demonstrated that T-2 binds to and inhibits TXNRD2 by occupying its FAD/NADPH-binding pocket. Notably, SeMet restored TXNRD2 expression and partially rescued mitochondrial injury, whereas direct TXNRD2 overexpression independently conferred comparable protection, confirming TXNRD2 as the key downstream effector. These interventions attenuated the abnormal elevation of intracellular ATP content and reduced ROS overproduction by approximately 39%. Conversely, TXNRD2 knockdown attenuated SeMet’s efficacy to establish TXNRD2 as a direct mitochondrial target of the T-2 toxin. Supplementation with SeMet protected cells by restoring both the expression and enzymatic activity of TXNRD2 and preventing T-2 toxin-induced cytotoxicity.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"45 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spatially Partitioned Engineering of an Alginate Lyase Overcomes the Stability–Activity Trade-Off via Distal Cap Loop Rigidification and Network Remodeling","authors":"Mengxuan Zhao,Mengqi Zhao,Peiyi Zhang,Liqiang Fan,Xu Li,Chen Deng,Liming Zhao","doi":"10.1021/acs.jafc.6c09998","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c09998","url":null,"abstract":"The stability–activity trade-off limits engineering of alginate lyases for alginate oligosaccharide production. Here, a spatially partitioned semirational strategy coupled with the greedy accumulated strategy for protein engineering (GRAPE) was applied to an alginate lyase from Vibrio sp. The optimized variant M13 achieved a 4.6-fold increase in catalytic efficiency (kcat/Km) and an 11.4-fold extension of half-life at 50 °C. Molecular dynamics simulations indicated that distal Cap Loop rigidification suppresses thermal unfolding while Gate Loop flexibility is retained for catalysis. A67K reversion increased Cap Loop flexibility and shifted the optimal temperature from 40 to 30 °C, supporting its thermostability contribution. Residue interaction network analysis identified a Val272–Tyr260–Arg73 communication pathway associated with active site preorganization into a near-attack conformation. V272A reversion reduced kcat/Km by 45.7%, supporting its catalytic contribution. These findings show that spatial partitioning can concurrently improve thermostability and catalytic efficiency, providing a design principle for polysaccharide lyase engineering.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"42 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiaming Liu,Linqing Li,Xintong Cao,Linxuan Bian,Zhen Hao,Yinhang Cai,Peng Xiong,Xiutao Liu
{"title":"Multidimensional Engineering of β-Glucosidase Cel1A for Enhanced Sophorose Synthesis","authors":"Jiaming Liu,Linqing Li,Xintong Cao,Linxuan Bian,Zhen Hao,Yinhang Cai,Peng Xiong,Xiutao Liu","doi":"10.1021/acs.jafc.6c10094","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c10094","url":null,"abstract":"Sophorose is a potent cellulase inducer, but its enzymatic synthesis from glucose is limited by native β-glucosidases. Cel1A, a GH1 β-glucosidase from Trichoderma reesei, was engineered using a structure-, energy-, and sequence-guided semirational strategy combining alanine scanning, MM/PBSA analysis, UniKP prediction, saturation mutagenesis, and combinatorial screening, yielding T299G/K240H. This variant exhibited a 10.29-fold apparent higher catalytic efficiency (kcat/Km) relative to wild-type Cel1A, resulting in 12.24 ± 0.67 g L–1 sophorose in 12 h at 37 °C, corresponding to 1.02 ± 0.06 g L–1 h–1. Channel analysis, CaverDock calculations, and molecular dynamics simulations suggested that the mutations favored glucose entry and binding, weakened sophorose binding, and reduced conformational fluctuations. K240 substitutions modulated hydrolysis, transglycosylation, isomerization, and synthesis. These findings identify an improved Cel1A variant and provide a computational interpretation of its enhanced sophorose-synthesizing activity.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"73 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tianmiao Li,Hongyao Zhu,Yihong Xu,Depeng Yuan,Woo-Jong Hong,Xu Jiang,Ki-hong Jung,Yuan Hu Xuan
{"title":"DUFB Promotes Broad-Spectrum Disease Resistance by Stabilizing GS1;1 in Rice","authors":"Tianmiao Li,Hongyao Zhu,Yihong Xu,Depeng Yuan,Woo-Jong Hong,Xu Jiang,Ki-hong Jung,Yuan Hu Xuan","doi":"10.1021/acs.jafc.6c09661","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c09661","url":null,"abstract":"Excessive nitrogen (N) fertilization increases rice susceptibility to pathogens, yet the molecular links between N signaling and immunity remain largely unresolved. In this study, we identified three genes encoding DUF-domain-containing proteins, DUFA, DUFB, and DUFC, which were induced by Rhizoctonia solani (R. solani) infection and N treatment. Analyses of dufa/b/c mutant and overexpression lines showed that DUFA/B/C genes have functional redundancy and confer broad-spectrum resistance to sheath blight (ShB), blast, and bacterial blight. DUFA/B/C interacted with glutamine synthetase 1;1 (GS1;1), suggesting that distinct DUF proteins may converge on a shared GS1;1-associated defense pathway. Subsequent analyses demonstrated that DUFs enhance rice ShB resistance by inhibiting ubiquitin-mediated GS1;1 degradation. The GS1;1 protein level was reduced in high-nitrogen (HN) compared to in low-nitrogen (LN) conditions, implying that DUFB-GS1;1 signaling might be involved in N-dependent rice disease resistance. Overall, these findings reveal a mechanism linking the N status to rice immunity through DUFB-mediated stabilization of GS1;1.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"28 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yebao Chen,Jingwen Rao,Wenli Liang,Liu Yang,Xiaoyan Hu,Xiaoyu Dong,Yonghua Wang,Rongkang Hu
{"title":"Structural Rigidity and Nucleophilic Proximity Synergistically Enable Efficient High-Temperature Hydrolysis of Phthalate Esters by PestE","authors":"Yebao Chen,Jingwen Rao,Wenli Liang,Liu Yang,Xiaoyan Hu,Xiaoyu Dong,Yonghua Wang,Rongkang Hu","doi":"10.1021/acs.jafc.6c08537","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c08537","url":null,"abstract":"Phthalic acid esters (PAEs) are persistent environmental pollutants. Their industrial biodegradation demands thermostable, efficient hydrolases. We characterized PestE, a thermostable esterase hydrolyzing both dialkyl and monoalkyl PAEs. PestE retained >98% of its maximal activity in short-term assays at 80–100 °C, with minimal loss after 12 h, and retained ∼50% activity after 48 h at 80 °C, with 99.4% dibutyl phthalate degradation in 2 min. Molecular dynamics simulations indicated that hydrophobic core reorganization and increased surface hydrophilicity synergistically enhance thermostability by balancing global rigidity and local flexibility. Co-crystallization with monobutyl phthalate revealed a substrate-guiding tunnel and catalytic machinery (Ser157-His284-Asp254 triad and oxyanion hole Gly85/Gly86/Ala158) for two-step dealkylation. A key feature is the close proximity of the nucleophilic Ser157 to the substrate carbonyl carbon (2.8–3.1 Å), enabling efficient catalysis. Mutagenesis confirmed key hydrophobic residues for substrate binding and active-site stability. These findings establish PestE as a promising biocatalyst for industrial PAE degradation.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"45 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149218883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dual-Phosphorylated Pumpkin Seed Protein Pickering\u0000Emulsions: Structural Evolution, Interfacial Regulation, and Coffee\u0000Creamer Application Quality","authors":"Jianyu Huang,Dengmi Wang,Ziying Ruan,Hui Xu,Zhizhi Yang,Jicheng Chen","doi":"10.1021/acs.jafc.6c12935","DOIUrl":"https://doi.org/10.1021/acs.jafc.6c12935","url":null,"abstract":"Abstract Pumpkin seed protein (PSP) was modified with sodium tripolyphosphate (STP) and sodium trimetaphosphate (STMP) to improve Pickering emulsions. Phosphorylation increased with STMP content but plateaued at high ratios. Mass spectrometry identified phosphorylated Ser and Thr residues, while 31P NMR indicated multiple phosphorus environments. Modification altered protein conformation and surface charge, reduced particle size, and improved dispersion without major subunit degradation. Although emulsifying activity decreased, emulsion stability increased; mixed-phosphate treatments generally produced finer droplets and better resistance to centrifugal destabilization than single-phosphate treatments. A 4:1 STP/STMP ratio combined small droplet size with favorable wettability and interfacial adsorption, whereas higher STMP content did not consistently improve overall performance. In coffee beverages, increasing emulsion incorporation intensified phase separation and altered color and flavor. At a 1:9 emulsion-to-coffee ratio, phosphorylated PSP emulsion improved perceived body and smoothness while retaining coffee aroma, outperforming commercial creamer in balance and supporting its potential use as a plant-based food.","PeriodicalId":41,"journal":{"name":"Journal of Agricultural and Food Chemistry","volume":"11 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2026-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149210231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}