Beyond the Nut: Leaves as Natural Food Preservatives.

The pistachio tree () is globally renowned for its nutritious nuts, while its leaves remain an underutilized source of chemicals with significant potential value as food preservatives. Similar value may be found in the leaves of other wild species common in Central Asia, the Levant, and around the Mediterranean. Some species' leaves have been used as natural preservatives, demonstrating their effectiveness and highlighting their rich bioactive components. This review investigates the antioxidant and antimicrobial properties of leaves, comparing both cultivated and wild species. A comprehensive search was performed across several scientific databases, including PubMed, Scopus, Web of Science, and Google Scholar, utilizing a combination of keywords related to species and their bioactive compounds. The inclusion criteria focused on articles published in English from 2017 till the end of June 2024, analyzing the antioxidant and antimicrobial activities of leaves and employing relevant extraction methods. A total of 71 literature sources were included, covering species such as , , , and others sourced from countries such as Iran, Turkey, and Italy. This review found that leaves are rich in polyphenolic compounds and exhibit robust antioxidant and antimicrobial properties, with certain wild species outperforming , suggesting species-specific traits that enhance their preservative potential. The major findings indicate that extracts from wild species exhibit superior bioactivity, which could be harnessed for food preservation. These insights underscore the promising role of leaves as natural food preservatives, with further research needed to address challenges in extraction and application. Exploring their synergistic effects with other preservatives could lead to innovative solutions in food preservation while fostering local economic growth.