The morphological and microscopy were combined with DNA-barcoding, together with rapid TLC for the characterization of Piper betle (PB), P. nigrum (PN), P. retrofractum (PR), P. sarmentosum (PS), and P. wallichii (PW), five medicinal Piper plants announced in the Thai Herbal Pharmacopoeia (THP). The authentic plants collected from various locations and voucher Piper products bought from commercial sites in Thailand were studied. The reproductive parts of authentic plants were subjected to ensure their morphological characters. Using sequencing analysis and genetic divergence for analyzing discriminatory performance, ITS2 was selected from eight candidate DNA markers to authenticate the origin of Piper crude drugs together with microscopic and TLC profiles for examining their characters, admixtures, adulterants, and substituents. PB and PR exhibited unique characters of the species, with no admixture, adulteration, and substitution. PN showed no variable characters of morphology and genetics. However, the microscopy could illustrate some commercial products of PN sold in Thailand have been adulterated with rice starch and roasted rice. In the herbal trade, PS has been sold in the form of mixed leaf, root, and stem more than the isolated part, but there is no variable character of the species. PW has shown more than one character of species explained by microscopic, chemical components, and genetic data. In conclusion, the conventional and molecular pharmacognostic data combined with chemical profile of authentic five Piper plants could be applied to indicate the plant origin and clarify the situations of admixture, adulteration, and substitution of the commercial Piper products launched in Thailand.

Graphical abstract

中文翻译：

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传统和分子生药学特征与泰国草药药典中五种胡椒植物的化学特征相结合，以及它们在泰国的混合/掺假/替代情况

形态学和显微术与 DNA 条形码以及快速薄层色谱法相结合，用于表征蜉蝣(PB)、龙葵(PN)、裂叶蜣螂(PR)、垂叶蜣螂(PS) 和瓦氏蠊 (P. wallichii ) (PW)，泰国草药药典 (THP) 中公布了五种药用胡椒植物。从各地收集的正宗植物和凭证Piper对从泰国商业网站购买的产品进行了研究。对真实植物的生殖部分进行了检查，以确保其形态特征。使用测序分析和遗传差异分析鉴别性能，从八个候选 DNA 标记中选出 ITS2 来验证Piper的起源生药连同显微镜和 TLC 图谱，用于检查它们的特性、混合物、掺杂物和替代物。PB和PR表现出该物种的独特性，没有掺加、掺假和替代。PN 没有表现出形态学和遗传学的可变特征。然而，显微镜可以说明在泰国销售的一些 PN 商业产品已掺入大米淀粉和炒米。在草药贸易中，PS以叶、根、茎的混合形式销售多于孤立部分，但没有品种性状变化。PW 已经展示了不止一种物种特征，这些特征可以通过微观、化学成分和遗传数据来解释。总之，常规和分子生药学数据结合正宗五种药物的化学特征胡椒植物可用于标示植物原产地，并阐明在泰国上市的商业胡椒产品的混合、掺假和替代情况。

图形概要