# _Applied sciences_
## 3 Results and Discussion
### Micromorphology of Plant Parts  
Micromorphological studies of medicinal plants focus on examining the microscopic structure and characteristics of plant tissues. Analysing these specific plants will help ensure the quality and consistency of their medicinal preparations. Psychoactive compounds, such as salvinorin A, are found in the subcuticular space of peltate glandular trichomes (GTs) in _Salvia divinorum_[37]. The variety and distribution of trichome types--pellate, capitate, and non-glandular--differ among plant species and organs, which aids in the identification of medicinal plants [38; 39]. The leaves were distinguished by the presence of both glandular and non-glandular trichomes that are present on the leaves of _G. fruticosus_ (Figure 3A,B). The non-glandular trichomes exhibited varying lengths (Figure 3A). A similar type of glandular trichomes has been reported in _Asclepius curassavica_, which also possesses antidepressant effect [40]. Figure 3: Scanning electron micrographs of _Gomphacarpus fruticosus_ leaves. (**A**) Leaf with trichomes, (**B,C**) cross section of leaves, and (**D**) multiple stoma/stomata. GT = glandular trichome, NGT = non-glandular trichomes, SM = secretory material, DC = druse crystal, Sh = sheath cell, and St = stoma/stomata. Flattened and elongated secretory cells were identified by outlining the periphery of the cavity (Figure 3B). These cells, known as sheath cells, serve as a protective layer that encases the secretory cavity [41]. The secretory material within typically contains a variety of compounds, including terpenes, phenolics, and polysaccharides [39]. These phytochemicals likely contribute to the management of depressive disorders by modulating various mechanisms [10]. The milky white latex produced by _G. fruticosus_ is secreted by this secretory material and is considered a synapomorphy of the Apocynaceae [42]. Due to the composite nature of latex secretion, often comprising a variety of specialised metabolites, several latex-bearing plants are renowned for their specific substances [43]. Stomatal occurrences were also observed (Figure 3D). Stomata primarily serve two functions: facilitating the uptake of carbon dioxide and restricting water loss through evaporation [44]. Additionally, druse crystals were distributed throughout the mesophyll and phloem of the leaves (Figure 3C). Plants utilise druse crystals to store surplus calcium in the form of calcium oxalate, and this reservoir can be mobilised as necessary during the calcium control process [45]. Microscopy examination of _L. leonurus_ leaf surfaces revealed two distinct types of trichomes, namely glandular and non-glandular trichomes (Figure 4A-E). This highlights the presence of dense non-glandular trichomes, suggesting enhanced protection for the plant. These structures act as mechanical barriers, offering defence against excessive water loss and various external factors [46]. Glandular trichomes, evenly distributed across the entire leaf surface, are identified as pellate trichomes, characterised by a large disc-like head and a short stalk (Figure 4D). Each glandular trichome exhibits morphological divisions in three regions: the multicellular head, stalk, and basal cavities [47]. These trichomes are recognised for storing and secreting waves and phytochemicals, including phenolics, terpenes, flavonoids, and alkaloids. This chemical arsenal provides both chemical and physiological protection against herbivores and pathogens [39]. [PERSON] et al. [48] reported similar findings with _L. leonurus_ and comparable trichome morphology has been established in other plants within the Lamiaceae family [49] and also in _Cannubis sativa_, which is sometimes used to alleviate psychiatric symptoms, such as anxiety, depression, and mania [50]. The micromorphology of plant, particularly features such as glandular and non-glandular trichomes, affects the production and storage of bioactive compounds [51].