Investigation of formation of well-known AGEs precursors in cookies using an in vitro simulated gastrointestinal digestive system

Glyoxal and methylglyoxal formation in chocolate and their bioaccessibility

The objective of this study was to assess the effects of simulated digestion on the formation of α-dicarbonyl compounds (α-DCs) in chocolates. For that purpose, the concentrations of glyoxal and methylglyoxal in chocolates were determined through High-Performance Liquid Chromatography (HPLC) analysis before and after in vitro digestion. The initial concentrations ranged from 0.0 and 228.2 µg/100 g, and 0.0 and 555.1 for glyoxal and methylglyoxal, respectively. Following digestion, there was a significant increase in both glyoxal and methylglyoxal levels, reaching up to 1804 % and 859 %, respectively. The findings indicate that digestive system conditions facilitate the formation of advanced glycation end product (AGE) precursors. Also, glyoxal and methylglyoxal levels were found to be low in chocolate samples containing dark chocolate. In contrast, they were found to be high in samples containing hazelnuts, almonds, pistache, and milk. Further studies should focus on α-DCs formation under digestive system conditions, including the colon, to determine the effects of gut microbiota.

Methylglyoxal scavenging capacity of fiber-bound polyphenols from highland barley during colonic fermentation and its modulation on methylglyoxal-interfered gut microbiota

Methylglyoxal (MGO) scavenging capacity of fiber-bound polyphenols from highland barley during colonic fermentation and its potential role in modulating MGO-induced detrimental effects on gut microbiota were studied. Results showed that only 25.3 % of polyphenols were released after 24 h of colonic fermentation. More than 45.5 % of MGO was scavenged by the residual fiber-bound polyphenols in the model system, showing a vital role in scavenging MGO in the colonic lumen compared to the released polyphenols. Moreover, MGO promoted the increase of gut pathogens (Escherichia-Shigella and Klebsiella) and inhibited the proliferation of Megasphaera, Bifidobacterium and Megamonas, as well as reduced short-chain fatty acids (SCFAs) concentration. The addition of fiber-bound polyphenols of highland barley could effectively counteract MGO-induced detrimental consequences on gut microbiota and SCFAs production. These results demonstrate that fiber-bound polyphenols from highland barley can exert beneficial role through scavenging MGO and promises to be a functional ingredient to maintain colon heath.

Glyoxal in Foods: Formation, Metabolism, Health Hazards, and Its Control Strategies

Glyoxal is a highly reactive aldehyde widely present in common diet and environment and inevitably generated through various metabolic pathways in vivo. Glyoxal is easily produced in diets high in carbohydrates and fats via the Maillard reaction, carbohydrate autoxidation, and lipid peroxidation, etc. This leads to dietary intake being a major source of exogenous exposure. Exposure to glyoxal has been positively associated with a number of metabolic diseases, such as diabetes mellitus, atherosclerosis, and Alzheimer's disease. It has been demonstrated that polyphenols, probiotics, hydrocolloids, and amino acids can reduce the content of glyoxal in foods via different mechanisms, thus reducing the risk of exogenous exposure to glyoxal and alleviating carbonyl stresses in the human body. This review discussed the formation and metabolism of glyoxal, its health hazards, and the strategies to reduce such health hazards. Future investigation of glyoxal from different perspectives is also discussed.

Investigating Bioaccessibility of Advanced Glycation Product Precursors in Gluten-Free Foods Using In Vitro Gastrointestinal System

Background and Objectives: Gluten-free products have been produced as part of medical therapy and have gained popularity among individuals seeking weight loss or healthier dietary options. Assessing the potential risks associated with these products is essential in optimizing their compositions and developing new dietetic approaches. This study aimed to determine the glyoxal (GO) and methylglyoxal (MGO) contents in gluten-free bread, biscuits, and cookies and to examine their bioaccessibility using an in vitro gastrointestinal model. Materials and Methods: A total of 26 gluten-free and 19 gluten-containing (control) products were analyzed for their GO and MGO levels utilizing a high-performance liquid chromatography (HPLC) device. Results: Post-digestion, the GO and MGO values increased significantly across all food groups compared with pre-digestion values (p < 0.05), and the bioaccessibility exceeded 100%. Specifically, gluten-free bread exhibited higher post-digestion GO and MGO values than the control group (p < 0.05). Conversely, gluten-containing biscuits and cookies had higher post-digestion GO and MGO values compared to gluten-free products (p < 0.05). Conclusions: The detection of precursors to advanced glycation end products (AGEs) in gluten-free products has drawn attention to the potential health risks associated with their consumption. Therefore, reevaluation of the formulations and technologies used in these products and the introduction of new strategies are crucial in mitigating AGE content.