Comparative study on morpho-anatomy of leaf, stem and root of Boerhaavia diffusa L. (Nyctaginaceae) and its adulterant plants

ABSTRACT Punarnava (Boerhaavia diffusa L.- Nyctaginaceae) is a promising drug to rejuvenate new cells in the body. It is well known in Ayurvedic medicine and locally called Tambadivasu. Superficially it is similar to other species of Boerhaavia and species of Trianthema and Sesuvium. Due to the minute morphological differences, the above plants are erroneously used in medicine as Punarnava, and at times on purpose as an adulterant. Therefore, it is necessary to highlight the anatomical features of Punarnava for proper identification of the medicinal plant species for local people and for scientific research. Due to the ambiguity in local names and similar apparent appearance, market samples of Punarnava are often adulterated with various species of Trianthema and Sesuvium. These adulterated samples contain neither the Punarnavine alkaloid, nor does it possess anisocytic stomata but possess paracytic stomata. Comparative study of stem anatomy showed two main characteristic differences. First, plenty of starch grains can be seen in both the ground parenchymatous tissues present in between successive cambia and xylem parenchyma of Punarnava which is not observed in species of Trianthema, and second, the phloem around the xylem of Punarnava root has semi-circular or eccentric patches, while that of Trianthema only has narrow strips. This study is focused on comparative SEM study of leaf morphologies and anatomy of leaf, stem, and root of Boerhaavia diffusa L., Trianthema portulacastrum L. and Sesuvium portulacastrum L.

摘要：波叶黄细心（Boerhaavia diffusa L.，紫茉莉科Nyctaginaceae）是一种极具潜力的机体细胞再生药用植物。其在阿育吠陀医学中应用广泛，当地俗称Tambadivasu。从表观形态来看，该植物与黄细心属（Boerhaavia）、三柱草属（Trianthema）及海马齿属（Sesuvium）的其他物种相似度极高。由于形态学差异细微，上述植物常被误当作波叶黄细心入药，部分情况下还会被故意作为掺伪品混入药材。鉴于当地命名存在歧义且表观外观相似，市场流通的波叶黄细心药材常被三柱草属和海马齿属的多个物种掺伪。此类掺伪样品既不含波叶黄细心碱（Punarnavine）生物碱，也不具备异细胞型气孔（anisocytic stomata），反而具有平列型气孔（paracytic stomata）。茎解剖结构的比较研究揭示了两项核心特征差异：其一，波叶黄细心的连续形成层之间的基本薄壁组织与木质部薄壁组织中均含有大量淀粉粒，而三柱草属物种中未观察到此特征；其二，波叶黄细心根部木质部周围的韧皮部呈半圆形或偏心性斑块状，而三柱草属的韧皮部仅为狭窄条带。本研究聚焦于波叶黄细心（Boerhaavia diffusa L.）、马齿苋状三柱草（Trianthema portulacastrum L.）及海马齿（Sesuvium portulacastrum L.）的叶形态、叶片、茎及根的解剖结构的扫描电子显微镜（SEM）比较研究。