Ghaf microgreen: A novel functional food with enhanced nutritional content via nanoparticle-seed priming

Introducing novel microgreens from the UAE-native ghaf plant into culinary traditions enriches dishes with nutrients and addresses sustainability challenges related to nutritional security. Microgreens are renowned for their dense nutrient profile compared with mature plants. This study investigated the potential of leveraging nanotechnology to enhance the resilience and productivity of ghaf microgreens and enhance their economic and nutritional values. Using ZnO-NPs at a concentration of 500 ng/mL significantly stimulated the germination of ghaf seed, which peaked after 5 days (93%) compared with the control (22%). Analysis of mineral content revealed a considerable increase in the majority of the essential nutrients, particularly Zn, which increased by 9–10-fold in treated seeds and microgreens compared with the control. The treatment of ZnO-NPs enhanced phytochemical concentration; the phenolic content increased from 379.70 to 415.22 mgGAE/100 gDW in the treated seed and from 501.43 to 774.81 mgGAE/100 gDW in the produced microgreens, thereby enhancing antioxidant activity. Variations in individual phenolic compounds, such as sinapic, gallic, and benzoic acids as well as rutin hydrate, were observed, with sinapic acid demonstrating the highest content in ghaf seed and microgreen leaves (34% more than that of the control). Furthermore, ZnO-NPs enhanced protein synthesis from 2.21 to 2.83 mg/mL in the ghaf microgreens, rendering it a high-value functional food. This study provides valuable insights into the physiological and nutritional responses of ghaf seed to ZnO-NPs treatment, laying the groundwork for NP-based strategies to enhance ghaf crop resilience and nutritional value in arid environments.