Anatomical and Histochemical Variation in Hellenia speciosa Leaves Across Developmental Stages

Pacing (Hellenia speciosa (J. Koenig) S.R. Dutta) is a species of the Costaceae family that grows as an herbaceous plant with simple leaves. Pacing leaves have potency as a medicinal plant. This study aims to characterize the anatomical and histochemical features of pacing leaves at two developmental stages and to analyze their potential as a medicinal plant. The method used is the free hand section method, paradermal method, and histochemical analysis. Anatomical structures were observed in the midrib, intercostal region, leaf margin, and petiole. In the two developmental stages, pacing leaves are differentiated into dermal, ground, and vascular tissues. The ground tissue is differentiated into palisade and spongy mesophyll with a dorsiventral arrangement. Tissue thickness is greater in mature leaves compared to young leaves. Stomatal density is higher on the abaxial surface, with a greater number observed in young leaves. In addition, non-glandular trichomes are present in the epidermal tissue, with higher density in young leaves. Histochemical analysis revealed positive results for alkaloids, flavonoids, phenolics, tannins, terpenoids, and lipids, with varying staining intensities in each tissue. Young leaves showed stronger histochemical staining for several alkaloid and flavonoid reactions, whereas mature leaves showed stronger staining for several phenolic, tannin, terpenoid, and lipid reactions; these qualitative intensities should not be interpreted as quantitative concentrations.