Iron and magnesium concentrations of mint accessions (Mentha spp.)

Plant foods can contribute significantly to human nutrition and health, because they contain almost all essential human nutrients. However, nutrient composition varies among different plant foods. Improvement of nutritional quality of our food supply, especially with respect to essential nutrient minerals, such as magnesium, iron and zinc, could be an important goal of vegetable crops. There is little information available on essential mineral concentration of mint (Mentha spp.). This study was conducted to evaluate some micronutrient minerals of twelve Iranian mint accessions, three of which belonging to Mentha longifolia (Mzin5, Mzin6 and Mzin11) and the remaining were Mentha spicata L species (Mzin1, Mzin2, Mzin3, Mzin4, Mzin7, Mzin8, Mzin9, Mzin10, and Mzin12). This report is assigned to two essential human nutrients, iron (Fe) and magnesium (Mg) concentrations of two mint herbage harvests in 12 mint clones within each of two studied years. Results of analysis of variance indicated a significant difference among accessions and a non-significant difference between species for Mg and Fe concentrations. Mean comparisons showed that Mzin2, Mzin12 (both belong to M. spicata) and Mzin6 (belongs to M. longifolia) possess the highest Fe concentration. Furthermore, Mzins 5, 6 and 11 belong to M. longifolia as well as Mzins 2 and 10 belong to M. spicata did not significantly differ and all included the first ranking group for Mg concentration. Fe concentration averaged on the first harvest ranged from 134mg/kg for Mzin4 genotype (belongs to M. spicata) to 210mg/kg to for Mzin5 genotype (belongs to M. longifolia), while Fe concentration at the second harvest varied from 315mg/kg for Mzin1 to 582mg/kg for Mzin12. At the first harvest, Mg concentration ranged from 748mg/kg for Mzin1 to 1174 for Mzin5. At the second harvest, Mg concentration varied from 1171mg/kg for Mzin9 to 1618mg/kg for Mzin11. It is hence concluded that the magnesium and iron concentrations of Mentha species are comparable to those reported for other leafy vegetable crops. Therefore, this is evidence that this herb is rich in some essential nutrient minerals, especially Fe and Mg which are essential for human health.