The glycation of amino acids with carbonyl groups of reducing sugars produces advanced glycation end-products (AGEs). These AGEs can be harmful to health over time. The research objective was to compare the effects of 0-1.00 mM chlorogenic acid (CGA) and caffeic acid (CA) on AGEs formed in glucose-lysine solutions at 25 °C, 63 °C and 100 °C for 30 and 60 minutes by measuring fluorescent AGEs: vesperlysine A and B, vesperlysine C, and total AGEs, and non- fluorescent carboxymethyl-lysine (CML) and carboxyethyl-lysine (CEL) with LC-MS. Chlorogenic acid inhibited the formation of AGEs to a greater extent compared to CA at 25 °C due to CGA’s lower pKa causing it to oxidize faster, thus forming highly reactive quinones that successfully competed with dicarbonyl intermediates and formed quinone-protein adducts, as well as CGA’s higher antioxidant capacity due to having more hydroxyl groups. In contrast both CGA and CA enhanced AGE formation the most at 63 °C, compared to 25 °C and 100 °C likely due to the formation of pro-oxidants from the thermal degradation of the HCAs. With further heating, a balance of antioxidants and pro-oxidants were present, causing no significant inhibition or enhancement of fluorescent AGEs at 100 °C. LC-MS analysis revealed that carboxyethyl-lysine (CEL) was formed in higher quantities than carboxymethyl-lysine (CML); however, there was no inhibition or enhancement of CEL or CML at 63 °C or 100 °C. Overall, temperature had the greatest impact on the formation of AGEs. The significance of the study was to determine which HCA exhibited higher AGE inhibition so that it can later be further investigated and used as an ingredient in beverages to lower exogenous AGE formation.
","abstract_html":"<p>The glycation of amino acids with carbonyl groups of reducing sugars produces advanced glycation end-products (AGEs). These AGEs can be harmful to health over time. The research objective was to compare the effects of 0-1.00 mM chlorogenic acid (CGA) and caffeic acid (CA) on AGEs formed in glucose-lysine solutions at 25 °C, 63 °C and 100 °C for 30 and 60 minutes by measuring fluorescent AGEs: vesperlysine A and B, vesperlysine C, and total AGEs, and non- fluorescent carboxymethyl-lysine (CML) and carboxyethyl-lysine (CEL) with LC-MS. Chlorogenic acid inhibited the formation of AGEs to a greater extent compared to CA at 25 °C due to CGA’s lower pKa causing it to oxidize faster, thus forming highly reactive quinones that successfully competed with dicarbonyl intermediates and formed quinone-protein adducts, as well as CGA’s higher antioxidant capacity due to having more hydroxyl groups. In contrast both CGA and CA enhanced AGE formation the most at 63 °C, compared to 25 °C and 100 °C likely due to the formation of pro-oxidants from the thermal degradation of the HCAs. With further heating, a balance of antioxidants and pro-oxidants were present, causing no significant inhibition or enhancement of fluorescent AGEs at 100 °C. LC-MS analysis revealed that carboxyethyl-lysine (CEL) was formed in higher quantities than carboxymethyl-lysine (CML); however, there was no inhibition or enhancement of CEL or CML at 63 °C or 100 °C. Overall, temperature had the greatest impact on the formation of AGEs. The significance of the study was to determine which HCA exhibited higher AGE inhibition so that it can later be further investigated and used as an ingredient in beverages to lower exogenous AGE formation.</p>","abstract_has_math":false,"creators":["Yapor, Christianne"],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Thesis","degree_discipline":"Food Science","degree_department":null,"school":null,"contributors":["Lilian Senger","Aftab Ahmed","Gabriel Davidov-Pardo","John Miklavcic"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-05-01T07:00:00Z","date_published":"2024-05-01T07:00:00Z","updated_at":"2026-07-24T01:38:43Z","subjects":["Advanced glycation end-products","caffeic acid","chlorogenic acid","carboxymethyl- lysine","fluorescence","LC-MS","Food Chemistry"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://digitalcommons.chapman.edu/food_science_theses/36","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Lilian Senger","Aftab Ahmed","Gabriel Davidov-Pardo","John Miklavcic"]},{"key":"dc:creator","label":"Author","values":["Yapor, Christianne"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2026-05-10T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Food Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Advanced glycation end-products","caffeic acid","chlorogenic acid","carboxymethyl- lysine","fluorescence","LC-MS","Food Chemistry"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.chapman.edu/food_science_theses/36"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The glycation of amino acids with carbonyl groups of reducing sugars produces advanced glycation end-products (AGEs). These AGEs can be harmful to health over time. The research objective was to compare the effects of 0-1.00 mM chlorogenic acid (CGA) and caffeic acid (CA) on AGEs formed in glucose-lysine solutions at 25 °C, 63 °C and 100 °C for 30 and 60 minutes by measuring fluorescent AGEs: vesperlysine A and B, vesperlysine C, and total AGEs, and non- fluorescent carboxymethyl-lysine (CML) and carboxyethyl-lysine (CEL) with LC-MS. Chlorogenic acid inhibited the formation of AGEs to a greater extent compared to CA at 25 °C due to CGA’s lower pKa causing it to oxidize faster, thus forming highly reactive quinones that successfully competed with dicarbonyl intermediates and formed quinone-protein adducts, as well as CGA’s higher antioxidant capacity due to having more hydroxyl groups. In contrast both CGA and CA enhanced AGE formation the most at 63 °C, compared to 25 °C and 100 °C likely due to the formation of pro-oxidants from the thermal degradation of the HCAs. With further heating, a balance of antioxidants and pro-oxidants were present, causing no significant inhibition or enhancement of fluorescent AGEs at 100 °C. LC-MS analysis revealed that carboxyethyl-lysine (CEL) was formed in higher quantities than carboxymethyl-lysine (CML); however, there was no inhibition or enhancement of CEL or CML at 63 °C or 100 °C. Overall, temperature had the greatest impact on the formation of AGEs. The significance of the study was to determine which HCA exhibited higher AGE inhibition so that it can later be further investigated and used as an ingredient in beverages to lower exogenous AGE formation.
"]},{"key":"dc:source","label":"Dc Source","values":["Yapor, C. (2024). Chlorogenic and caffeic acids’ impact on formation of fluorescent and non-fluorescent advanced glycation end-products as a function of temperature. Master's thesis, Chapman University. https://doi.org/10.36837/chapman.000588"]},{"key":"dc:title","label":"Title","values":["Chlorogenic and Caffeic Acids’ Impact on Formation of Fluorescent and Non-Fluorescent Advanced Glycation End-Products as a Function of Temperature"]}]}],"canonical_facts":{"dc:contributor":["Lilian Senger","Aftab Ahmed","Gabriel Davidov-Pardo","John Miklavcic"],"dc:creator":["Yapor, Christianne"],"dc:date.available":["2026-05-10T07:00:00Z"],"dc:description.abstract":["The glycation of amino acids with carbonyl groups of reducing sugars produces advanced glycation end-products (AGEs). These AGEs can be harmful to health over time. The research objective was to compare the effects of 0-1.00 mM chlorogenic acid (CGA) and caffeic acid (CA) on AGEs formed in glucose-lysine solutions at 25 °C, 63 °C and 100 °C for 30 and 60 minutes by measuring fluorescent AGEs: vesperlysine A and B, vesperlysine C, and total AGEs, and non- fluorescent carboxymethyl-lysine (CML) and carboxyethyl-lysine (CEL) with LC-MS. Chlorogenic acid inhibited the formation of AGEs to a greater extent compared to CA at 25 °C due to CGA’s lower pKa causing it to oxidize faster, thus forming highly reactive quinones that successfully competed with dicarbonyl intermediates and formed quinone-protein adducts, as well as CGA’s higher antioxidant capacity due to having more hydroxyl groups. In contrast both CGA and CA enhanced AGE formation the most at 63 °C, compared to 25 °C and 100 °C likely due to the formation of pro-oxidants from the thermal degradation of the HCAs. With further heating, a balance of antioxidants and pro-oxidants were present, causing no significant inhibition or enhancement of fluorescent AGEs at 100 °C. LC-MS analysis revealed that carboxyethyl-lysine (CEL) was formed in higher quantities than carboxymethyl-lysine (CML); however, there was no inhibition or enhancement of CEL or CML at 63 °C or 100 °C. Overall, temperature had the greatest impact on the formation of AGEs. The significance of the study was to determine which HCA exhibited higher AGE inhibition so that it can later be further investigated and used as an ingredient in beverages to lower exogenous AGE formation.
"],"dc:identifier":["https://digitalcommons.chapman.edu/food_science_theses/36"],"dc:source":["Yapor, C. (2024). Chlorogenic and caffeic acids’ impact on formation of fluorescent and non-fluorescent advanced glycation end-products as a function of temperature. Master's thesis, Chapman University. https://doi.org/10.36837/chapman.000588"],"dc:subject":["Advanced glycation end-products","caffeic acid","chlorogenic acid","carboxymethyl- lysine","fluorescence","LC-MS","Food Chemistry"],"dc:title":["Chlorogenic and Caffeic Acids’ Impact on Formation of Fluorescent and Non-Fluorescent Advanced Glycation End-Products as a Function of Temperature"],"thesis:degree_discipline":["Food Science"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T01:38:43Z"}