[Herbal textural research, morphologic characteristics and DNA barcoding of botanical origins of Alismatis Rhizoma]

Alismatis Rhizoma(Zexie) is a commonly used traditional Chinese medicine, and it is separated into "Chuan Zexie"(Sichuan and Hubei provinces), "Jian Zexie"(Fujian and Jiangxi provinces) and "Guang Zexie"(Guangxi province) according to different producing areas. Alisma plantago-aquatica and A. orientale were listed as the original plants of Alismatis Rhizoma in different editions of Chinese Pharmacopoeia(Ch.P), respectively. The botanical origins of Alismatis Rhizoma caused much controversy during a period of time. This study aimed to define the botanical origins of Alismatis Rhizoma from different producing areas, and supply scientific evidence for Ch. P 2020 edition. In this paper, we summarized the descriptions of original plants and producing areas of Alismatis Rhizoma in ancient literatures. Flowers and fruits of original plants of Alismatis Rhizoma were collected from different typical areas, and compared with the morphological description of two species from Alisma genus in the Flora of China. Thirty-nine batches of leaves from 8 different areas were identified using DNA barcoding technology. The results showed that original plants of Alismatis Rhizoma from different areas could be distinguished from each other based on morphological characteristics and molecular characteristics. Then, "Jian Zexie" was identified as A. orientale, while "Chuan Zexie" and "Guang Zexie" were identified as A. plantago-aquatica. In conclusion, combining with herbal textural research, morphologic characteristics, DNA barcoding technology and market situation, this paper recommended that the botanical sources of Alismatis Rhizoma could be revised as Alisma orientale(Sam.) Juzep. and Alisma plantago-aquatica Linn. in the Ch. P 2020 edition.