Agronomic biofortification of sand soil with iron, zinc, and selenium enhances morphological and physiological characteristics of peppermint (Mentha piperita L)

A micronutrient shortage affects nearly half of people worldwide. These include iron (Fe), zinc (Zn), and selenium (Se), which are primarily associated with poorer dietary intake of micronutrients in diets. Peppermint growth and production are negatively impacted by low nutritional levels and poor climatic circumstances in Egypt’s desert regions. Agronomic biofortification (AGB) is the quickest and least expensive way to address Fe, Zn, and Se micronutrient shortages; additionally, it enhances the quality of meals. The main target of this study was to enhance the nutritional quality, active substances and biochemical constituents of peppermint through agronomic biofortification, with a focus on increasing the levels of key micronutrients such as Fe, Zn, and Se. Peppermint plants exposed to different doses of Fe (0, 0.2, 0.4, 0.6, and 0.8 g L−1), Zn (0, 0.1, 0.2, 0.3, and 0.4 g L−1) and Se (0, 0.02, 0.04, 0.06, and 0.08 g L−1). Mass production, photosynthetic pigments, essential oil (EO), soluble sugars (SOLS), Fe, Zn, Se and antioxidant enzymes (GPX, GR, POX, SOD, CAT) were measured. Additionally, the fortified plants were blended in proportions designed to provide a rat’s recommended daily intake of Fe, Zn, and Se; food intake, body weight, Zn, triglycerides, glucose, LDL-cholesterol, cholesterol, HDL cholesterol, malondialdehyde and glutathione were evaluated. One-way analysis of variance (ANOVA) was applied to assess the averaged data statistically. Application of Fe, Zn, and Se especially higher doses enhanced peppermint yield, various chemical constituents and different biological properties. Spraying plants with Fe resulted in a 79.9% increase in carvone (major component of essential oil) and 181.9% SOD. Plants subjected to Zn gave the maximum values of dry mass (345.6%), dry root (298.8%), Ch b (140%), TCAR, (307.1%), EO yield (133.3%), SOLS (437.5%), GPX (216.7%) and GR (138.5%). While, plant treated with Se produced the highest increases in fresh mass (188.5%), fresh roots (407.7%), Ch a (113.7%), utilized element (466.7%), POX, (111.1%) and CAT (280%). Animal experiments have shown that plants biofortified with the daily dose of Fe (1.5 mg/150 g), Zn (4.5 mg/150 g) and Se (0.03 mg/150 g) were the best in terms of physiological properties. It can be recommended to spray the peppermint with Fe, Zn and Se in amounts of 0.8, 0.4 and 0.08 g L−1, respectively. It would be possible to increase the concentrations of Fe, Zn, and Se in peppermint herbs by implementing a nutrition program that applies these elements to Egypt’s sand soil. Micronutrients are minerals that the body needs in small amounts and are crucial for maintaining overall health. Agronomic biofortification in herbs primarily aims to boost the concentration of compounds that promote health. The levels of Fe, Zn, and Se in herbs can be increased through a program that applies these specific elements.