In the context of Advanced Glycation End-products (AGEs), the term “advanced” refers to the irreversible and structurally stable adducts formed during the final stages of the glycation reaction. These compounds are closely linked to the onset and progression of various chronic diseases influenced by dietary patterns, including diabetes, cardiovascular conditions, and neurodegenerative disorders. Elucidating the pathways and dynamics of AGE formation is critical not only in clinical chemistry but also in collaboration with food chemistry. Methylglyoxal (MGO), a major precursor of AGEs, is an intermediate metabolite of glycolysis that reacts rapidly and specifically with the guanidino group of arginine residues to form MG-H1 (Methylglyoxal Hydroimidazolone 1). Due to the rapidity and specificity of this reaction, MGO and/or MG-H1 (hereafter referred to as MGO/MG-H1) are attracting attention as early markers of glycation stress. Moreover, MGO serves as a modulator of oxidative stress by acting as a source of radicals through its interactions with transition metals and impairing mitochondrial function. Additionally, it can promote the generation of reactive oxygen (ROS) via the activation of NADPH oxidase (NOX) through receptor for AGEs (RAGE) signaling. This review highlights the contributions of three internationally recognized research groups that have significantly advanced the field of MGO/MG-H1 research, with a focus on their impact in both clinical and food chemistry contexts. Thornalley et al. (UK) laid the groundwork for MGO/MG-H1 research by elucidating non-enzymatic MGO formation pathways, glyoxalase system-mediated detoxification, and the site-specific (hotspot) modifications of MG-H1. Beisswenger et al. (USA) demonstrated correlations between MG-H1 levels in human blood and urine and decreased glomerular filtration rate (eGFR) and albuminuria, suggesting MG-H1 as an early biomarker of diabetic nephropathy. Schalkwijk et al. (Netherlands) investigated the role of MGO/MG-H1 in the progression of chronic kidney disease, endothelial dysfunction, and inflammation. Notably, they compiled a comprehensive database of carboxymethyl lysine (CML), carboxyethyl lysine (CEL), and MG-H1 contents in 141 food items and have pioneered dietary intervention studies focused on food-derived AGEs, particularly MG-H1. This article discusses analytical methods based on the chemical characteristics of MGO/MG-H1, with particular attention to sample preparation in LC-MS/MS analysis and enzyme-linked immunosorbent assay (ELISA) measurements. Based on these technical backgrounds and human-derived data, we emphasize that MGO/MG-H1 should not merely be regarded as precursors to AGEs, but as early markers of glycation and oxidative stress, and more importantly, as “key molecules” linking endogenous metabolism, diet, and disease.

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Aspartame is a widely used artificial sweetener. For quality control purposes, it is necessary to quantify the impurities l-aspartyl- d-phenylalanine methyl ester (l, d-APM) and 5-benzyl-3,6-dioxo-2-piperazine acetic acid (DKP). However, the sale of l, d-APM standards has been temporarily suspended in Japan, leading to significant analytical challenges for the conventional HPLC method. Additionally, a method that can simultaneously quantify aspartame, l, d-APM, and DKP to improve analytical efficiency is required. In this study, we developed a method for the simultaneous analysis of aspartame, l, d-APM, and DKP using the relative molar sensitivity (RMS) based on ¹H-quantitative nuclear magnetic resonance (¹H-qNMR) spectroscopy. Standard solutions prepared based on the accurate purity of each compound determined by ¹H-qNMR were analyzed by HPLC, and the RMS values for aspartame were calculated from the slope ratio of the calibration curve. In method validation using samples spiked with aspartame, no statistically significant differences were observed between the RMS method and the conventional absolute calibration method, demonstrating excellent precision. The proposed method enables reliable simultaneous quantification without the use of challenging to obtain quantitative standards while maintaining compatibility with existing regulatory HPLC conditions and improving analytical efficiency. Furthermore, it could significantly improve the quality control of aspartame.

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Rare sugar syrup (RSS), developed through alkaline isomerization of high-fructose corn syrup (HFCS), contains rare sugars such as D-allulose, which are associated with anti-obesity and anti-diabetic effects. This study investigated the effects of RSS on the physicochemical properties, fermentation behavior, staling rate, and volatile compound profile of sour bread, in comparison with breads made using sucrose (Suc) and without added sugar (Blk). The addition of 5°Bx RSS resulted in a greater loaf volume compared with the 5°Bx Suc and Blk samples, likely due to improved gas retention capacity. Volatile compound analysis showed moderate concentrations of alcohols and higher levels of esters, furans, and alkadienes, reflecting the distinct flavor and aroma of RSS-bread compared to the others. RSS-bread exhibited a significantly lower staling rate and retained a softer texture during storage at 25 °C. Furthermore, RSS-bread demonstrated the most effective mold growth suppression, extending storage period to 17 ± 5 days, compared with 6 ± 0 days for Blk-bread and 7 ± 1 days for Suc-bread. These results suggest that RSS can serve as a functional sugar alternative in sour bread, enhancing shelf life and texture without compromising fermentation performance.

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This study aimed to evaluate the anti-inflammatory effects of various strains of Saccharomyces cerevisiae on HaCaT cells. Two yeast samples, S. cerevisiae CK34, CK78, and two commercial powders (Yeast powder HA, Yeast powder HG), were tested for their ability to suppress inflammation. No anti-inflammatory activity was observed in Yeast powder HA and HG, while S. cerevisiae CK34 and CK78 exhibited significant effects. All four samples were subsequently subjected to fractionation using a cation-exchange resin, and the anti-inflammatory properties of each resulting fraction were assessed. Among these, Fraction 5 (Fr.5) from S. cerevisiae CK78, Yeast powder HA, and Yeast powder HG demonstrated notable anti-inflammatory activity. LC/MS, LC/MS/MS, and heat map analysis of each yeast’s Fr.5, combined with cell-based assays, identified inosine as one of the bioactive components responsible for the observed effect in S. cerevisiae CK78.

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Soybean lecithin is known as a naturally derived emulsifier and has been widely utilized in various fields such as food, pharmaceuticals, and cosmetics. In this study, we investigated the physicochemical stability and intestinal delivery of corn ceramide emulsions prepared with enzyme-hydrolyzed soybean lecithin (SLP-lyso), compared to those prepared using non-hydrolyzed soybean lecithin (SLP). The SLP-lyso emulsions exhibited smaller and more uniform particle sizes and maintained excellent stability even under strongly acidic conditions (pH 1.2). This stability is likely due to the enhanced hydrophilicity and interfacial activity of lysolecithin. Furthermore, in an artificial intestinal membrane model, SLP-lyso emulsions suggested greater membrane adsorption than SLP emulsions. These findings suggest that lysolecithin-based ceramide emulsions could improve oral delivery through enhanced stability and intestinal adsorption upon oral administration.

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This study validates an analytical method for quantifying canthaxanthin and β-apo-8'-carotenal, two carotenoid food additives that were recently approved in Japan; however, an official method for quantifying the contents of these compounds in foods is lacking. These compounds, which serve as food coloring agents with established Acceptable Daily Intakes (ADIs) of 0.025 and 0.05 mg/kg body weight/day, respectively, require reliable analytical methods for regulatory compliance and safety monitoring. We modified a method from the literature and evaluated its performance according to the Guidelines for Validation of Analytical Methods for Food Additives in Foods. The proposed method demonstrated good sensitivity with a lower quantification limit of 0.1 μg/mL (0.001 g/kg food content) and good linearity within the tested concentration range. Recovery tests on four food products yielded satisfactory recovery rates, repeatability, and intra-laboratory precision, meeting all guideline criteria. The proposed technique provides a reliable analytical method for determining canthaxanthin and β-apo-8'-carotenal content in tested food products. These results support the potential applicability of this technique as an official quantification method for regulatory monitoring and food safety assurance.

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A regulatory limit has been established in Japan for the total concentration of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) and Δ⁹- tetrahydrocannabinolic acid (Δ⁹-THCA), in cannabidiol (CBD) products. For CBD isolate powder, a raw material, a strict limit of 10 ppm is set for total Δ⁹-THC levels. However, due to the reported monitoring ions shared by CBD and Δ⁹-THC on LC-MS/MS analysis, conventional dilution-based methods suffer from significant signal interference, which makes accurate quantification of Δ⁹- THC in high-CBD-content matrices. In this study, we developed the normal-phase liquid chromatographic (DCpak^® P4VP column) preparation for an LC-MS/MS method to accurately quantify trace levels of Δ⁹-THC in CBD isolate powder. This sample preparation was validated based on spike-and-recovery tests (repeatability and intermediate precision) at three concentration levels (1, 5, and 10 μg/g in sample) which demonstrated excellent accuracy (94.3%–108.9%) and RSD (≤3.6%) using internal standard curves with Δ⁹- THC-d₃, respectively. This improved method enables reliable quantification of at regulatory levels in high-CBD products such as isolates and others in compliance with the Japanese guidelines for analytical method validation of food additives.

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