Hydroethanolic extract of Juglans regia L. green husks: A source of bioactive phytochemicals


Juglans regia L. (walnut) green husks are an important fraction of waste resulting from the walnut production, thus representing an interesting natural matrix to explore as a source of bioactive compounds. In this work, the hydroethanolic extract of walnut green husks was studied considering the phytochemical composition and the biological activity using different cell model assays, most of them evaluated for the first time for this matrix. From the HPLC-DAD-ESI/MSn analysis, sixteen compounds were identified, being the extract mostly composed of naphthalene derivatives (including tetralone derivatives) and less abundant in phenolic compounds (hydroxycinnamic acids and flavonols). The cytotoxic potential of the extract was assessed against tumour (MCF-7, NCI-H460, HeLa and HepG2) and non-tumour (PLP2) cell lines. Moreover, the antioxidant activity of the extract was evaluated by inhibition of the oxidative haemolysis (OxHLIA) and the formation of thiobarbituric acid reactive substances (TSARS), and the anti-inflammatory potential by the inhibition of the NO production by the RAW264.7 cell culture. The antibacterial effects of the extract were also evaluated against Gram-negative and Gram-positive bacteria. The results obtained represent a stepping stone for the development of future applications using walnut green husks as a source of added value compounds with bioactive potential.



subject category

Food Science & Technology; Toxicology


Vieira, V; Pereira, C; Abreu, RMV; Calhelha, RC; Alves, MJ; Coutinho, JAP; Ferreira, O; Barros, L; Ferreira, ICFR

our authors


The authors thank the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2019) and V. Vieira grant (SFRH/BD/108487/2015); national funding by FCT, P.I., through the institutional scientific employment program-contract for L. Barros and R. Calhelha contracts, and C. Pereira contract celebrated though the program-contract foreseen in No. 4, 5 and 6 of article 23 of Decree -Law No. 57/2016, of 29th August, amended by Law No. 57/2017, of 19th July. To UID/CTM/50011/2019 (CICECO), financed by national funds through the FCT/MCTES. To POCI-01-0145-FEDER-006984 (LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020 and FCT. To project AllNat - POCI-01-0145-FEDER-030463 (PTDC/EQU-EPQ/30463/2017), funded by FEDER funds through COMPETE2020 Programa Operacional Competitividade e Internacionalizacao (POO), and by national funds through Foundation for Science and Technology (FCT/MCTES), and to FEDER-Interreg Espana-Portugal programme for financial support through the project 0377_Iberphenol_6_E.

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".