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Journals / International Journal of Secondary Metabolite / 2026 / Volume: 13 Issue: 3

Phytochemical composition and bioactivities of Turkish walnut (Juglans regia L.) septum extracts

Gamze Kaplan(BALIKESİR ÜNİVERSİTESİ)0000-0002-3968-322X
Serap Doğan(BALIKESİR ÜNİVERSİTESİ, FEN-EDEBİYAT FAKÜLTESİ)0000-0001-5684-3662
Pınar Güner(BALIKESİR ÜNİVERSİTESİ, FEN-EDEBİYAT FAKÜLTESİ)0000-0001-6922-7009
Fatih Satıl(BALIKESİR ÜNİVERSİTESİ, FEN-EDEBİYAT FAKÜLTESİ)0000-0002-4938-1161
Mehmet Emin Diken(BALIKESİR ÜNİVERSİTESİ)0000-0003-3349-939X
Pages
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Publication Date
2026-09-02
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Overall, these findings highlight WS as a valuable natural source of bioactive compounds with significant antioxidant, antimicrobial, and enzyme inhibitory properties, supporting its potential use in functional food and nutraceutical applications.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Walnut (Juglans regia L.) septum (WS) is an underutilised by-product despite its rich phytochemical potential.
📊
Key Findings & Data:The WS extracts contained a diverse phenolic profile, with vanillic acid (17.13-53.62 µg/g) and quercetin (14.96-16.53 µg/g) identified as the predominant compounds.
💡
Conclusion & Impact:Overall, these findings highlight WS as a valuable natural source of bioactive compounds with significant antioxidant, antimicrobial, and enzyme inhibitory properties, supporting its potential use in functional food and nutraceutical applications.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Walnut Septum · Antidiabetic · Antimicrobial

Abstract

Walnut (Juglans regia L.) septum (WS) is an underutilised by-product despite its rich phytochemical potential. In this study, WS extracts obtained by water and CO₂-assisted extraction were phytochemically characterised, and their antioxidant, antimicrobial, and enzyme inhibitory activities were systematically evaluated. The WS extracts contained a diverse phenolic profile, with vanillic acid (17.13-53.62 µg/g) and quercetin (14.96-16.53 µg/g) identified as the predominant compounds. The extracts exhibited high total phenolic (10.56–11.05 mg GAE/g) and flavonoid contents (27.92–32.42 mg QE/g), which were reflected in their strong antioxidant capacities. Notably, WS extracts demonstrated potent radical scavenging activity, with IC₅₀ values ranging from 0.15 to 0.34 mg/mL, along with high ferric reducing power (approximately 38.5 mg TE/mL). In addition to antioxidant activity, the extracts showed marked biological functionality. The CO₂-assisted extract displayed enhanced α-amylase inhibitory activity (IC₅₀: 0.96 mg/mL), indicating notable antidiabetic potential, whereas the aqueous extract exhibited broader antimicrobial efficacy, particularly against Candida albicans and Saccharomyces cerevisiae. Overall, these findings highlight WS as a valuable natural source of bioactive compounds with significant antioxidant, antimicrobial, and enzyme inhibitory properties, supporting its potential use in functional food and nutraceutical applications.

Özet

Walnut (Juglans regia L.) septum (WS) is an underutilised by-product despite its rich phytochemical potential. In this study, WS extracts obtained by water and CO₂-assisted extraction were phytochemically characterised, and their antioxidant, antimicrobial, and enzyme inhibitory activities were systematically evaluated. The WS extracts contained a diverse phenolic profile, with vanillic acid (17.13-53.62 µg/g) and quercetin (14.96-16.53 µg/g) identified as the predominant compounds. The extracts exhibited high total phenolic (10.56–11.05 mg GAE/g) and flavonoid contents (27.92–32.42 mg QE/g), which were reflected in their strong antioxidant capacities. Notably, WS extracts demonstrated potent radical scavenging activity, with IC₅₀ values ranging from 0.15 to 0.34 mg/mL, along with high ferric reducing power (approximately 38.5 mg TE/mL). In addition to antioxidant activity, the extracts showed marked biological functionality. The CO₂-assisted extract displayed enhanced α-amylase inhibitory activity (IC₅₀: 0.96 mg/mL), indicating notable antidiabetic potential, whereas the aqueous extract exhibited broader antimicrobial efficacy, particularly against Candida albicans and Saccharomyces cerevisiae. Overall, these findings highlight WS as a valuable natural source of bioactive compounds with significant antioxidant, antimicrobial, and enzyme inhibitory properties, supporting its potential use in functional food and nutraceutical applications.

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Cite This Article

Kaplan, G., Doğan, S., Güner, P., Satıl, F., Diken, M. E. (2026). Phytochemical composition and bioactivities of Turkish walnut (Juglans regia L.) septum extracts. International Journal of Secondary Metabolite, Volume: 13 Issue: 3. https://doi.org/10.21448/ijsm.1904196

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