Gastric digestion-induced transformation of acorn phenolics from Quercus rubra and Quercus robur: antioxidant activity, multi-target enzyme inhibition, and molecular docking insights
- 1Institute of Food Technology and Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology 2/22 Stefanowskiego Street 90-537 Lodz Poland [email protected].
- 2Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Technická 5 166 28 Prague Czech Republic [email protected].
- 3Institute of Molecular and Industrial Biotechnology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology Lodz 90-537 Poland.
Abstract
Acorns, the fruits of Quercus spp., represent an underutilized source of bioactive phenolic compounds. In this study, phenolic-rich fractions isolated from Quercus rubra and Quercus robur acorns were evaluated to characterize their bioactive phenolic profiles, antioxidant properties, and inhibitory activity against multiple enzyme targets, and to determine how simulated gastric digestion affects these biological activities. UHPLC-DAD-ESI-HRMS/MS analysis revealed that the two Quercus fractions differed markedly in their individual phenolic profiles, especially in ellagitannin composition. Despite compositional changes, both native and gastric-digested fractions retained considerable antioxidant and multi-target enzyme-inhibitory activity. The Q. rubra fraction, rich in oenothein B and rugosin E isomers, showed stronger acetylcholinesterase (AChE) inhibition (IC₅₀: 0.25 mg mL⁻¹), whereas the Q. robur fraction, characterized by castalagin/vescalagin-type compounds and tellimagrandin II isomers, was more active against tyrosinase (TYR), α-amylase (AMY), α-glucosidase (GLU) (IC₅₀: 0.080, 0.22, and 1.8, mg mL⁻¹, respectively). Notably, simulated gastric digestion preserved or even enhanced the inhibitory activity of the Q. rubra fraction against pancreatic lipase (PNLIP), AMY, as well as α-GLU. Molecular docking analysis showed that the predominant ellagitannins identified in both oak fractions exhibited strong predicted affinities toward the multiple enzyme targets. Tellimagrandin II showed particularly high affinity for AChE and TYR (-10.6 and -8.6 kcal mol⁻¹, respectively). Oenothein B showing the highest affinity for GLU (-11.3 kcal mol⁻¹) and vescavaloninic acid for AMY (-10.2 kcal mol⁻¹). Castalagin showed the strongest predicted interaction with PNLIP (-9.3 kcal mol⁻¹). Interestingly, low-molecular-weight phenolics whose levels increased after gastric digestion, particularly ellagic acid, also exhibited strong predicted affinities for AChE (-10.0 kcal mol⁻¹) and PNLIP (-9.2 kcal mol⁻¹). These results suggest that Q. rubra and Q. robur acorns may represent valuable sources of bioactive compounds with antioxidant and enzyme-modulating potential, particularly toward enzymes associated with neurodegenerative processes, melanogenesis, carbohydrate digestion, and lipid metabolism.
Related
- Preparation, Spectroscopic Elucidation, Antioxidant Potential, Enzyme Inhibition, and Molecular Docking Studies of Novel Schiff Base-Derived Thiosemicarbazones.
- Mechanistic Insights into Polyphenol Oxidase Inhibition by Four Bioactive Constituents from Hydrangea macrophylla Serrata: Antioxidant Activity of Single Compounds Compared to the Whole-Leaf Extract
- Green synthesis of ZnO nanoparticles using pomegranate husk extract: comparative evaluation of antioxidant, enzyme inhibition, and cytotoxic properties
- Polyol-Functionalized Manganese-Based Nanoparticles: From Insulin Amyloid Inhibition to Nanozyme-Mediated Antioxidant Activity
- Reactive molecular dynamics insights into oxidation-induced degradation of ofloxacin and toxicity assessment of its transformation products
BibTeX
@article{popowska2026gastric,
title = {{Gastric digestion-induced transformation of acorn phenolics from Quercus rubra and Quercus robur: antioxidant activity, multi-target enzyme inhibition, and molecular docking insights}},
author = {Aleksandra Popowska and Barbora Strasserova and Marcin Szustak and Gabriela Kowalska and Kamila Kulbat-Warycha and Aristeidis S Tsagkaris and Joanna Oracz},
journal = {RSC advances},
year = {2026},
month = nov,
doi = {10.1039/d6ra08016b},
url = {https://europepmc.org/article/PMC/PMC13725865},
note = {CC BY},
}
RIS
TY - JOUR
TI - Gastric digestion-induced transformation of acorn phenolics from Quercus rubra and Quercus robur: antioxidant activity, multi-target enzyme inhibition, and molecular docking insights
AU - Aleksandra Popowska
AU - Barbora Strasserova
AU - Marcin Szustak
AU - Gabriela Kowalska
AU - Kamila Kulbat-Warycha
AU - Aristeidis S Tsagkaris
AU - Joanna Oracz
PY - 2026
DA - 2026/11/02
JO - RSC advances
DO - 10.1039/d6ra08016b
UR - https://europepmc.org/article/PMC/PMC13725865
AB - Acorns, the fruits of Quercus spp., represent an underutilized source of bioactive phenolic compounds. In this study, phenolic-rich fractions isolated from Quercus rubra and Quercus robur acorns were evaluated to characterize their bioactive phenolic profiles, antioxidant properties, and inhibitory activity against multiple enzyme targets, and to determine how simulated gastric digestion affects these biological activities. UHPLC-DAD-ESI-HRMS/MS analysis revealed that the two Quercus fractions differed markedly in their individual phenolic profiles, especially in ellagitannin composition. Despite compositional changes, both native and gastric-digested fractions retained considerable antioxidant and multi-target enzyme-inhibitory activity. The Q. rubra fraction, rich in oenothein B and rugosin E isomers, showed stronger acetylcholinesterase (AChE) inhibition (IC₅₀: 0.25 mg mL⁻¹), whereas the Q. robur fraction, characterized by castalagin/vescalagin-type compounds and tellimagrandin II isomers, was more active against tyrosinase (TYR), α-amylase (AMY), α-glucosidase (GLU) (IC₅₀: 0.080, 0.22, and 1.8, mg mL⁻¹, respectively). Notably, simulated gastric digestion preserved or even enhanced the inhibitory activity of the Q. rubra fraction against pancreatic lipase (PNLIP), AMY, as well as α-GLU. Molecular docking analysis showed that the predominant ellagitannins identified in both oak fractions exhibited strong predicted affinities toward the multiple enzyme targets. Tellimagrandin II showed particularly high affinity for AChE and TYR (-10.6 and -8.6 kcal mol⁻¹, respectively). Oenothein B showing the highest affinity for GLU (-11.3 kcal mol⁻¹) and vescavaloninic acid for AMY (-10.2 kcal mol⁻¹). Castalagin showed the strongest predicted interaction with PNLIP (-9.3 kcal mol⁻¹). Interestingly, low-molecular-weight phenolics whose levels increased after gastric digestion, particularly ellagic acid, also exhibited strong predicted affinities for AChE (-10.0 kcal mol⁻¹) and PNLIP (-9.2 kcal mol⁻¹). These results suggest that Q. rubra and Q. robur acorns may represent valuable sources of bioactive compounds with antioxidant and enzyme-modulating potential, particularly toward enzymes associated with neurodegenerative processes, melanogenesis, carbohydrate digestion, and lipid metabolism.
SN - 2046-2069
ER -