eprintid: 27556 rev_number: 6 eprint_status: archive userid: 2 dir: disk0/00/02/75/56 datestamp: 2026-02-25 23:30:15 lastmod: 2026-02-25 23:30:15 status_changed: 2026-02-25 23:30:15 type: article metadata_visibility: show creators_name: Zhao, Yuxuan creators_name: Liang, Jingyimei creators_name: Lu, Rui creators_name: Zou, Zebin creators_name: Wu, Haoming creators_name: Chen, Shengxiong creators_name: Cao, Hui creators_name: Xiao, Jianbo title: Thermal activation in oxidative model drives catechin assembly into theaflavins with enhanced antioxidant capacity ispublished: pub subjects: uneat_sn divisions: uneatlantico_produccion_cientifica full_text_status: none abstract: Theaflavins are important bioactive pigments in tea, but their non-enzymatic formation pathways under heating remain incompletely understood. This study investigated the temperature-dependent formation of four theaflavins using aqueous catechin model systems. Potassium ferricyanide was used as a controlled oxidant to initiate catechin oxidation and subsequent coupling reactions. Liquid chromatography-mass spectrometry (LC-MS), ultraviolet-visible spectroscopy (UV–Vis), DPPH and ABTS assays were applied to track product profiles and antioxidant capacity. Moderate temperatures promoted catechin oxidation to ortho-quinones and favored the accumulation of theaflavins, leading to higher antioxidant activity. Low temperatures limited conversion, whereas high temperatures accelerated precursor consumption and theaflavin degradation. Across all model systems, theaflavin levels peaked at 30 min and then declined with prolonged heating. Among the four products, TF3 showed the strongest thermoresponsive and the highest antioxidant capacity. These findings reveal a thermally activated catechin self-assembly mechanism in an oxidant-assisted model system. date: 2026-02 publication: Food Chemistry volume: 508 pagerange: 148334 id_number: doi:10.1016/j.foodchem.2026.148334 refereed: TRUE issn: 03088146 official_url: http://doi.org/10.1016/j.foodchem.2026.148334 access: close language: en citation: Artículo Materias > Alimentación Universidad Europea del Atlántico > Investigación > Artículos y libros Cerrado Inglés Theaflavins are important bioactive pigments in tea, but their non-enzymatic formation pathways under heating remain incompletely understood. This study investigated the temperature-dependent formation of four theaflavins using aqueous catechin model systems. Potassium ferricyanide was used as a controlled oxidant to initiate catechin oxidation and subsequent coupling reactions. Liquid chromatography-mass spectrometry (LC-MS), ultraviolet-visible spectroscopy (UV–Vis), DPPH and ABTS assays were applied to track product profiles and antioxidant capacity. Moderate temperatures promoted catechin oxidation to ortho-quinones and favored the accumulation of theaflavins, leading to higher antioxidant activity. Low temperatures limited conversion, whereas high temperatures accelerated precursor consumption and theaflavin degradation. Across all model systems, theaflavin levels peaked at 30 min and then declined with prolonged heating. Among the four products, TF3 showed the strongest thermoresponsive and the highest antioxidant capacity. These findings reveal a thermally activated catechin self-assembly mechanism in an oxidant-assisted model system. metadata Zhao, Yuxuan; Liang, Jingyimei; Lu, Rui; Zou, Zebin; Wu, Haoming; Chen, Shengxiong; Cao, Hui y Xiao, Jianbo mail SIN ESPECIFICAR (2026) Thermal activation in oxidative model drives catechin assembly into theaflavins with enhanced antioxidant capacity. Food Chemistry, 508. p. 148334. ISSN 03088146