A Comprehensive Review on the Chemical Constituents and Functional Uses of Walnut (<i>Juglans</i> spp.) Husk

• Main Authors: Ali Jahanban-Esfahlan, Alireza Ostadrahimi, Mahnaz Tabibiazar, Ryszard Amarowicz
• Format: Article
• Language: English
• Published: MDPI AG 2019-08-01
• Series: International Journal of Molecular Sciences
• Subjects: by-products; functional applications; fruit; husk; walnut
• Online Access: https://www.mdpi.com/1422-0067/20/16/3920

The walnut (<i>Juglans</i> spp.) is an appreciated nut that belongs to the Juglandaceae family. The fruit includes four main parts: the kernel, the skin, the shell, and the green husk. It is widely cultivated due to its edible kernel. In walnut production centers, high amounts of the husk as an agro-forest waste product are produced and discarded away. Recently, it has been demonstrated that the walnut green husk could be valued as a source of different natural bioactive compounds with excellent antioxidant and antimicrobial properties. Regarding this respect, in this contribution, the current scientific knowledge on the antioxidant and antiradical activities, various identified and isolated individual chemical constituents, as well as the functional applications of the walnut husk with more emphasis on the Persian walnut (<i>Juglans regia</i> L.) are reviewed.