Identification of “Huoshan shihu” Fengdou: Comparative authentication of the Daodi herb Dendrobium huoshanense and its related species by macroscopic and microscopic features

Abstract

"Huoshan shihu," derived from Dendrobium huoshanense, is a well-known, valuable, and rare Daodi herb. Because of its higher price and scarce resources, its related species D. officinale and D. moniliforme are usually presented as "Huoshan shihu" for sale. Fengdou, the processed form of D. huoshanense, its identification is particularly important. To effectively identify Fengdou of D. huoshanense and protect the Daodi herb, the morphological and microscopic characteristics of the stems of three Dendrobium species were examined. The results showed that macroscopic and microscopic features helpful for identification of the three species were the total lengths and internode numbers of stems, diameter and length of each internode, number of vascular bundles, and presence or absence of silica masses. The key features useful for distinguishing between D. huoshanense and its related species, and also between their Fengdou, were the stem lengths and the trends of change in diameter in different internodes. The results of the study indicated that a combination of macroscopic and microscopic identification techniques might conveniently and effectively be applied for identification of Dendrobium species. "Longtou Fengwei" is the main feature of the Daodi herb "Huoshan shihu," (D. huoshanense Fengdou) and reflects the wisdom behind the protection of Daodi herbs in ancient times.

Developmental anatomy of anomalous structure and classification of commercial specifications and grades of the Astragalus membranaceus var. mongholicus

“…Modern microscopic authentication is a fast, simple, effective, low cost, and less toxic method for distinguishing Chinese Materia Medica (Qin et al, ). And this method of combining macroscopic with microscopic characteristics is widely used in the identification of Chinese Materia Medica (Zhao et al, ; Wang, Yang, Peng, & Qian, ). In the market, the Special Class is considered to be of good quality, and the Huangqi with hollow is of bad quality; however, the hollow also existed in the Special Class.…”

Compare the microscopic characteristics of stems of the 24 Dendrobium species utilized in the traditional Chinese medicine “Shihu”

“…The researchers of these previous studies, however, only investigated the middle part of stem. In particular, the experiment with D. huoshanense , D. officinale , and D. moniliforme conducted by Zhao et al () found that the vascular bundle numbers in their stems varied not only in species but also in the same stem. In keeping with our previous work, we found that the number of vascular bundles in stems of 24 Dendrobium species also have changed at different internodes, and showed a trend of first increasing and then decreasing.…”

“…Yu et al () had a microscopic study on D. officinale and its similar species, and found that there were differences in epidermal cells, subcutaneous cells, vascular bundles, and so on. The previous study, however, showed that, besides the above points, there were differences in the changes of vascular bundle numbers in the different internodes for D. huoshanense , D. officinale, and D. moniliforme , and the structure of the vascular bundle in the middle internode was more stable (Zhao et al, ). This is similar to the vascular characteristics of monocotyledonous plant, bamboos (Yao, Yi, Ma, Wang, & Li, ).…”

“…Previous studies found that the number of vascular bundles of the Dendrobium plant stems presented certain trends in changes of node positions (Zhao et al, 2017). Therefore, in order to facilitate statistics and description, internodes of 24 Dendrobium species were numbered.…”

“…Raphides occurred in mucilage cells near the epidermis (Figure 8a2), such as D. loddigesii Their study had demonstrated that the key feature useful for distinguishing D. officinale was "two hat-shaped" vascular bundle sheath. Zhao et al (2017) found that the vascular bundle numbers in their stems varied not only in species but also in the same stem. In keeping with our previous work, we found that the number of vascular bundles in stems of 24 Dendrobium species also have changed at different internodes, and showed a trend of first increasing and then decreasing.…”