Samples of Banlangen and Daqingye.

Background Isatidis Folium (Daqingye, DQY) and Isatidis Radix (Banlangen, BLG) are the leaf and root of the plant Isatis tinctoria Fort. (syn. Isatis indigotica Fort.), commonly prescribed for detoxification, and the inhibition of viral and oxidative activities. Given their widespread use, we set forth to investigate the authenticity and chemical composition of DQY and BLG samples obtained from eighteen administrative districts in the Hong Kong market. Methods The present study screened the identities and chemical composition of DQY and BLG through molecular authentication and HPLC methods, respectively. Molecular authentication utilized DNA barcoding, focusing on nuclear ribosomal and chloroplast regions. The HPLC methods were conducted in accordance with the Hong Kong Chinese Materia Medica Standards (HKCMMS). Results We found that only one sample was genuine according to the species definition in the Chinese Pharmacopoeia and HKCMMS for both herbs. The chemical composition of the adulterated and the genuine samples were completely different, that the adulterant samples did not have the standard chemical markers epigoitrin and indirubin of Banlangen and Daqingye as listed in the Chinese Pharmacopoeia. Conclusion Our investigation underscores the widespread substitution by Strobilanthes (Nanbanlangen and Nandaqingye) species, mainly due to the preference of use of this herb in southern China. The adulteration of Daqingye by Blumea balsamifera (Ainaxiang) was probably due to mislabeling in the herb shop, though the error might have originated from the supplying sources. We recommend providing education on the necessity of using authentic Daqingye and Banlangen, especially in combined regimens, to standardize treatment effects. More education is also needed on the morphological differentiation of Banlangen from Nanbanlangen and Daqingye from Nandaqingye. The implementation of a track-and-trace system is strongly recommended to prevent and deter incorrect supply chain practices that lead to substitution or adulteration.背景 菘蓝叶（Isatidis Folium，别名大青叶，DQY）与菘蓝根（Isatidis Radix，别名板蓝根，BLG）为植物菘蓝（Isatis tinctoria Fort.，异名Isatis indigotica Fort.）的干燥叶片与根部，二者临床常用于清热解毒、抑制病毒活性与抗氧化应激。鉴于二者临床应用广泛，本研究针对香港市场18个行政区采集的大青叶与板蓝根样本，开展真伪鉴别及化学成分分析。 方法 本研究分别采用分子鉴定法与高效液相色谱法（High Performance Liquid Chromatography, HPLC）对大青叶与板蓝根的物种真实性及化学成分进行筛查。分子鉴定采用DNA条形码技术，靶向核糖体核区域与叶绿体区域。高效液相色谱检测严格遵循《香港中药材标准》（Hong Kong Chinese Materia Medica Standards, HKCMMS）执行。 结果 研究结果显示，按照《中华人民共和国药典》及《香港中药材标准》中两种药材的物种定义，仅1份样本符合正品标准。掺伪样本与正品样本的化学成分存在显著差异：掺伪样本未检出《中华人民共和国药典》中规定的板蓝根与大青叶标准化学标志物表告依春（epigoitrin）和靛玉红（indirubin）。 结论 本研究证实，市场中广泛存在以马蓝属（Strobilanthes）物种（俗称南板蓝根、南大青叶）掺伪的现象，该现象主要源于中国南方地区的用药偏好。此外，还存在以艾纳香（Blumea balsamifera，别名Ainaxiang）掺伪大青叶的情况，该问题可能源于药材店的标签失误，亦可能源自上游供货环节。本研究建议开展科普宣教，阐明使用正品大青叶与板蓝根的必要性，尤其在复方配伍用药中，以保障临床疗效的一致性。同时，需加强公众对板蓝根与南板蓝根、大青叶与南大青叶形态鉴别知识的普及。此外，强烈建议建立溯源追踪系统，以防范和遏制供应链中存在的替代或掺伪等不规范操作。