School of Life Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa.
Plant Production Department, P.O. Box 2460, College of Food and Agriculture Sciences, King Saud University, Riyadh, 11451, Saudi Arabia.
Micron. 2022 Feb;153:103184. doi: 10.1016/j.micron.2021.103184. Epub 2021 Nov 18.
Heteropyxis natalensis Harv. is a native South African tree used in traditional medicine among Venda and Zulu communities. In this study, micromorphological investigations using light and scanning electron microscopy identified long, tapered non-glandular trichomes on the abaxial and adaxial surfaces of the leaves. The total number of trichomes appeared to be greater on emergent leaves and decreased as leaves matured. In addition, schizolysigenous secretory cavities and druse crystals were found within the leaves. Swollen subdermal secretory cavities were also distributed in the midrib of the leaves. Transmission electron microscopy confirmed the presence of nuclei, plastids, mitochondria, vesicles, rough endoplasmic reticulum cisternae and Golgi bodies in the secretory epithelia of these cavities. Various histochemical tests revealed the presence of alkaloids, phenolics, lipids, proteins, essential oils, resin acids and trace amounts of unesterified pectins and polysaccharides in the leaves. This study provides new findings and contributes to the existing research regarding H. natalensis with respect to the micromorphology, ultrastructure and histochemical composition of this species.
南非原生树种异叶南洋杉被文达族和祖鲁族用于传统医学。本研究采用光学显微镜和扫描电子显微镜进行微观形态学研究，结果表明其叶片的下表面和上表面均有长而渐细的非腺毛。叶出时非腺毛数量最多，随叶片成熟而逐渐减少。此外，叶片中还存在离生型分泌腔和砂晶。叶片的叶脉中也分布有膨胀的皮下分泌腔。透射电子显微镜证实了这些分泌腔的分泌上皮中存在细胞核、质体、线粒体、小泡、粗糙内质网池和高尔基体。各种组织化学测试表明，叶片中存在生物碱、酚类、脂类、蛋白质、精油、树脂酸和痕量未酯化的果胶和多糖。本研究为异叶南洋杉的微观形态、超微结构和组织化学组成提供了新的发现，并为该物种的现有研究做出了贡献。
