Weiying Lu

Coffee proteins are key precursors of roasting flavor. However, heat-driven changes in the bean proteome remain underexplored. This work aimed to investigate these changes and study proteomic markers of the coffee bean. The green and roasted coffee beans were quantified for their total soluble protein and compared by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) and liquid chromatography–mass spectrometry (LC–MS) proteomics. The protein profiles identified by LC–MS were processed using principal component analysis (PCA) and partial least-squares discriminant analysis (PLS–DA) modeling to identify possible roast-sensitive protein markers. The alkaline-aided aqueous extract protein concentration was reduced from 14–23 g to 3–10 g/100 g dry weight (DW). SDS–PAGE showed dominant 17–26, 34–43, and 55–72 kDa bands weakened after roasting, while high molecular peaks (>180 kDa) were present only in roasted samples. In-solution tryptic digestion yielded nine protein groups. PCA scores revealed partial separation of green and roasted groups, while PLS-DA delivered unambiguous classification (Q² > 0.90 by cross-validation). The variable importance in projection scores highlighted that structural proteins in common plant beans are markedly down-regulated after roasting, indicating heat-induced structural disruption. The identified protein groups represent candidate markers associated with severe thermal treatment and provide possible molecular targets for investigating flavor precursor development.

Chrysanthemum, a traditional medicinal and edible plant, possesses diverse health-promoting properties attributed to its rich profile of bioactive compounds. However, the intrinsic quality, influenced by the composition of fundamental components like starch and lignin, varies significantly across different cultivars and origins. This study establishes a comprehensive phytochemical profile of 12 representative Chinese chrysanthemum cultivars by systematically quantifying their starch and lignin contents. Furthermore, it develops and validates a novel, low-cost rapid detection method for starch utilizing smartphone-based colorimetry. The starch content, determined by a colorimetric anthrone-sulfuric acid assay, ranged from 2.68 to 18.69 g/100 g, while the lignin content, measured via the acetyl bromide digestion followed by UV spectrophotometry at 280 nm, varied from 4.21 to 13.63 g/100 g, revealing substantial inter-cultivar differences. For starch analysis, a low-cost, immediate, general-purpose, and high-throughput (LIGHt) smartphone-based colorimetry was implemented. Standard curves constructed from both absorbance and the LIGHt assay demonstrated excellent linearity (R² > 0.99). The method’s performance was evaluated under different lighting conditions and across various smartphone models. The UV spectrophotometry condenses lignin quantification to a single 30-min digestion–reading cycle, bypassing the two-day Klason protocol and increases efficiency greatly. The work successfully provides a foundational component analysis and validates a portable, high-throughput framework for on-site quality control of plant-based products, demonstrating the strong potential of smartphone-based colorimetry for rapid starch detection and a complementary laboratory-scale lignin assay.

As a part of a continuous 90 day subchronic toxicology study, integrated metabolomic and transcriptomic approaches were applied to assess the metabolic network changes in the livers of Kunming mice exposed to three typical thermally induced food toxicants, including oxidative derivatives of triacylglycerols (ox-TGs), aldehydes, and 3-monochloropropane-1,2-diol esters (3-MCPDE), as well as their mixtures. Results showed lipid metabolic dysregulation through impaired purine metabolism, PPAR signaling, and bile acid metabolism. Ox-TGs emerged as the most hazardous compound, altering over 10 genes/enzymes. 3-MCPDE exhibited gender-specific effects, significantly upregulating fatty acid metabolism and gluconeogenesis genes in males. Interestingly, toxicant mixtures attenuated the adverse metabolic effects caused by individual compounds, demonstrating complex regulatory mechanisms in fatty acid biosynthesis and oxidation. The metabolomic and transcriptomic analyses conducted in this study revealed that combined exposure to multiple toxicants generated during lipid thermal processing may induce more complex toxicity effects than the simple additive effects of individual toxicants. Certain antagonistic effects were observed when comparing individual toxicants to their mixtures, highlighting the need for further mechanistic verifications in this area.

A rapid and efficient detection method to detect the total starch in tobacco leaves using smartphone-based anthrone-sulfuric acid colorimetry is established under the framework of the low-cost, immediate, general-purpose, and high-throughput (LIGHt) smartphone-based colorimetry. The LIGHt smartphone colorimetry resulted average relative error of 5.74%, with a relative standard deviation (RSD) ranging from 2.58 to 4.31%, a detection limit of 1.53 µg/mL, and an average recovery rate of 95.72%. The results demonstrated that the LIGHt smartphone colorimetry perform comparably to the regular visible spectrophotometry in determining starch concentration, validating the feasibility of this novel colorimetric method, which requires no specific instruments. The LIGHt-based method indicated the feasibility and potential for application in the field of rapid quality detection of plant leaves and other food and medicinal-related quality control practices.

Chlorogenic acids (CGAs) play a key role in defining the quality and functionality of coffee products. CGA fingerprints of black instant coffee (BIC) and coffee bean extract (CBE) were profiled using ultra-performance liquid chromatography–mass spectrometry and analyzed by chemometrics. A total of 25 CGAs were identified. The BICs yielded higher levels of major CGAs than the CBEs. Furthermore, chemometrics methods, including principal component analysis (PCA) and partial least squares–discriminant analysis (PLS–DA), successfully classified the CBEs and the BICs. In vitro cellular antioxidant activity and viability assays between coffee products further confirmed the relationship between phenolic compounds and bioactivities. Compared to the CBEs, the BICs provided higher cellular toxicity and oxidant activity for hepatocellular carcinoma G2 (HepG2) cells. These results demonstrated that CGAs and their derivatives could be markers for studying coffee-related products. This study revealed the unique phenolic profiles of various coffee products, highlighting the differences between whole beans and soluble coffee.

Oxidative derivatives of triacylglycerols (ox-TGs), aldehydes, and 3-monochloropropane-1,2-diol esters (3-MCPDE) were simultaneously evaluated in a 90-day subchronic study, focusing on biological indicators, biochemical indicators, and serum metabolomics as the first part of integrated toxicity and interactions. After 90 days of feeding Kunming mice, coexposure to combined toxicants significantly inhibited the trend of liver weight gain, reduced the levels of total bilirubin (TBIL) and direct bilirubin (DBIL), and decreased uric acid (UA) compared to individual toxicant exposure. A total of 21 and 31 biomarkers in female and male mice were identified, respectively. Co-exposure to combined toxicants might mitigate the changes in cytidine, CDP, dUMP, and dUDP involved in purine and pyrimidine metabolism caused by a single exposure, but exacerbate the changes in l-tryptophan, 5-hydroxy-l-tryptophan, and 5-hydroxyindoleacetic acid, which are involved in tryptophan metabolism. These results provided new insights into a comprehensive toxicity and interaction evaluation model of multiple combined toxicants in food.

In this study, the influence of total sn-2 palmitic triacylglycerols (TAGs) and ratio of 1-oleoyl-2-palmitoyl-3-linoleoylglycerol (OPL) to 1,3-dioleoyl-2-palmitoylglycerol (OPO) in human milk fat substitute (HMFS) on the metabolic changes were investigated in Sprague–Dawley rats. Metabolomics and lipidomics profiling analysis indicated that increasing the total sn-2 palmitic TAGs and OPL to OPO ratio in HMFS could significantly influence glycine, serine and threonine metabolism, glycerophospholipid metabolism, glycerolipid metabolism, sphingolipid metabolism, bile acid biosynthesis, and taurine and hypotaurine metabolism pathways in rats after 4 weeks of feeding, which were mainly related to lipid, bile acid and energy metabolism. Meanwhile, the up-regulation of taurine, L-tryptophan, and L-cysteine, and down-regulations of lysoPC (18:0) and hypoxanthine would contribute to the reduction in inflammatory response and oxidative stress, and improvement of immunity function in rats. In addition, analysis of targeted biochemical factors also revealed that HMFS-fed rats had significantly increased levels of anti-inflammatory factor (IL-4), immunoglobulin A (IgA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px), and decreased levels of pro-inflammatory factors (IL-6 and TNF-α) and malondialdehyde (MDA), compared with those of the control fat-fed rats. Collectively, these observations present new in vivo nutritional evidence for the metabolic regulatory effects of the TAG structure and composition of human milk fat substitutes on the host.

In this study, the impact of sn-2 palmitic triacyclglycerols (TAGs) in combination with their ratio of two major TAGs (1-oleoyl-2-palmitoyl-3-linoleoylglycerol (OPL) to 1,3-dioleoyl-2-palmitoylglycerol (OPO)) in human milk fat substitute (HMFS) on bile acid (BA) metabolism and intestinal microbiota composition was investigated in newly-weaned Sprague–Dawley rats after four weeks of high-fat feeding. Compared to those of control group rats, HMFS-fed rats had significantly increased contents of six hepatic primary BAs (CDCA, αMCA, βMCA, TCDCA, TαMCA and TβMCA), four ileal primary BAs (UDCA, TCA, TCDCA and TUDCA) and three secondary BAs (DCA, LCA and ωMCA), especially for the HMFS with the highest sn-2 palmitic acid TAGs of 57.9% and OPL to OPO ratio of 1.4. Meanwhile, the inhibition of ileal FXR-FGF15 and activation of TGR5-GLP-1 signaling pathways in HMFS-fed rats were accompanied by the increased levels of enzymes involved in BA synthesis (CYP7A1, CYP27A1 and CYP7B1) in the liver and two key thermogenic proteins (PGC1α and UCP1) in perirenal adipose tissue, respectively. Moreover, increasing sn-2 palmitic TAGs and OPL to OPO ratio in HMFS also altered the microbiota composition both on the phylum and genus level in rats, predominantly microbes associated with bile-salt hydrolase activity, short-chain fatty acid production and reduced obesity risk, which suggested a beneficial effect on host microbial ecosystem. These observations provided important nutritional evidence for developing new HMFS products for infants.

Introduction: As one of the staple foods for the world’s major populations, the safety of wheat is critical in ensuring people’s wellbeing. However, mildew is one of the prevalent safety issues that threatens the quality of wheat during growth, production, and storage. Due to the complex nature of the microbial metabolites, the rapid identification of moldy wheat is challenging.Methods: In this research, identification of moldy wheat samples was studied using ultra-performance liquid chromatography - quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) coupled with chemometrics. The non-targeted PCA model for identifying moldy wheat from normal wheat was established by using previously established compounds database of authentic wheat samples. The partial least squares-discriminant analysis (PLS-DA) was performed.Results and discussion: By optimizing the model parameters, correct discrimination of the moldy wheat as low as 5% (w/w) adulteration level could be achieved. Differential biomarkers unique to moldy wheat were also extracted to identify between the moldy and authentic wheat samples. The results demonstrated that the chemical information of wheat combined with the existing PCA model could efficiently discriminate between the constructed moldy wheat samples. The study offered an effective method toward screening wheat safety.