Changes in the lipid composition and bioactive compounds of walnut (Juglans regia) under different storage conditions: implications for future research on polycystic ovary syndrome (PCOS)

Dalma Máté; Szende Vancea; Elek Ferencz; Eszter Laczkó-Zöld

doi:10.2478/orvtudert-2026-0009

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Changes in the lipid composition and bioactive compounds of walnut (Juglans regia) under different storage conditions: implications for future research on polycystic ovary syndrome (PCOS)

Bulletin of Medical Sciences

Volume 99 (2026): Issue 2 (December 2026)

By: Dalma Máté, Szende Vancea, Elek Ferencz and Eszter Laczkó-Zöld

Open Access

|Jul 2026

Abstract

Juglans regia L., commonly known as walnut and belonging to the Juglandaceae family, is one of the major plant sources rich in polyunsaturated fatty acids (PUFAs) and may have medicinal potential. To utilise walnuts as a functional food, it is essential to investigate the changes that occur in their chemical composition under different storage conditions. The aim of the present study was to evaluate the lipid profile, total phenolic content (TPC), antioxidant capacity, and phytosterol content of Juglans regia walnut samples obtained from different harvest years and stored under various conditions. Samples were examined in both in-shell whole-walnut (WW) and shelled walnut-kernel (WK) forms. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the fatty acid profile of the walnut samples was characterised by a predominance of linoleic acid. Our results showed that neither storage form nor harvest year caused substantial changes in fatty acid composition. Walnuts harvested in 2024 exhibited a higher total phenolic content than samples collected during the 2025 harvest; in the case of Tree 2, the 2024 WW samples had a significantly higher total phenolic content than the corresponding WK samples. A decrease in total phenolic content was observed in the 2025 samples stored in kernel form. No significant differences were detected in antioxidant activity, although the 2025 samples showed slightly lower values. Although no marked qualitative differences were observed in lipid composition, the thin-layer chromatographic profile suggested the presence of phytosterols. Overall, our findings indicate that the lipid composition of walnuts remained relatively stable under the investigated storage conditions, whereas the effects of storage form and harvest year were evident for certain bioactive constituents. Further studies are required to confirm the clinical relevance of the observed associations.

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Articles in this issue

DOI: https://doi.org/10.2478/orvtudert-2026-0009 | Journal eISSN: 2537-5059 | Journal ISSN: 1453-0953

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Language: English

Page range: 125 - 146

Published on: Jul 11, 2026

Published by: Transylvanian Museum Society

In partnership with: Paradigm Publishing Services

Publication frequency: 2 issues per year

Keywords:

Juglans regia,

polyunsaturated fatty acids (PUFAs),

phenolic compounds,

storage conditions,

polycystic ovary syndrome (PCOS)

Related subjects:

Life sciences,

Life sciences, other,

Medicine,

Clinical medicine,

Clinical medicine, other,

Pharmacy,

Pharmacy, other

© 2026 Dalma Máté, Szende Vancea, Elek Ferencz, Eszter Laczkó-Zöld, published by Transylvanian Museum Society
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Volume 99 (2026): Issue 2 (December 2026)