# _Applied sciences_
## 3 Results and Discussion
### Elemental Composition  
Common elements found in these plants include sodium (Na), calcium (Ca), magnesium (Mg), copper (Cu), manganese (Mn), selenium (Se), zinc (Zn), and iron (Fe) [53]. Studies in different regions have identified specific plants used for mental health treatments, such as _Tilia platyphyllos_ and _Valeriana officinalis_, in the Catalan linguistic area [54]. Although plants accumulate beneficial major elements, some may contain trace heavy metals at levels exceeding international safety standards [55]. The elemental analysis of _G. fruticosus_ leaves and _L. leourus_ leaves using SEM coupled with an energy-dispersive X-ray spectrometer revealed the presence of carbon (C), oxygen (O), magnesium (Mg), silicon (Si), phosphorus (P), chlorine (Cl), potassium (K), and calcium (Ca) (Table 1). The presence of the elements was found to be in decreasing order of C \(>\) O \(>\) K \(>\) Ca \(>\) Si \(>\) Cl \(>\) Mg \(>\) P in the leaves of _G. fruticosus_ and C \(>\) O \(>\) K \(>\) Ca \(>\) Mg \(=\) Cl \(>\) Si \(>\) P in the leaves of _L. Leourus_. The results indicated an abundance of C, O, K, and Ca in the two studied plants. These elements are crucial for photosynthesis (C and O), for breaking down sugars to obtain energy (C), for cellular respiration (O), for producing grains rich in starch and maintaining turgor (K), and for balancing organic acids within the plant, improving root growth conditions (Ca) [53]. A variety of factors, including climate and soil conditions influence the mineral composition of plants in different regions [56]. The nutritional value of plants is determined by these mineral elements, which are transported from soil to plant and eventually to humans [57]. The presence of specific elements such as calcium, magnesium, and potassium, can directly influence the synthesis and stability of bioactive compounds within the plant [58; 59]. These minerals often play a role as cofactors in enzymatic processes essential for metabolite synthesis, such as the production of flavonoids, alkaloids, and terpenes [58]. Figure 4: Scanning electron micrographs of _Leontis leourus_ leaves. (**A**) Abundant non-glandular trichomes were found in the leaves of the plant. (**B**) Stoma/stomata were found with glandular trichomes and non-glandular trichomes. Post-secretory glandular trichomes were also present. (**C–E**) Developing and developed glandular trichomes; non-glandular trichomes with cuticular wart. GT = glandular trichome, NGT = non-glandular trichomes, St = stoma/stomata, PS = post-secretory trichome, DGT = developing trichomes, and W = cuticular wart. Micronutrients such as copper (Cu), selenium (Se), Mg, K, and Ca assist in maintaining a stable mental state, and an imbalance of these minerals is associated with mental disorders [60]. As indicated in the current results, Mg, K, and Ca are present in all the plants selected for the study, and a deficiency in these mineral elements in humans increases the risk of depression via different pathways [60; 61]. Mg plays a vital role in maintaining the stability and functioning of the brain and central nervous system [62; 63]. The multiple possible mechanisms of magnesium involvement in depression and anxiety involve the blockage of the glutamatergic N-methyl-D-aspartate (NMDA) [64] and its receptors (NMDAR) [65], which modulates the serotoninergic system [66], and alterations in the gut microbiota, leading to a negative impact on the gut-brain axis [67]. For all the present minerals, there was no significant difference. P and Ca are two essential minerals that play a crucial role in maintaining overall physical and mental well-being. Phosphorus governs the proper functioning of the nervous system, muscle contractions, and other vital physiological processes, whereas Ca is paramount for the transmission of nerve impulses, muscle function, and the release of neurotransmitters [68; 69].