Department of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland.
Research Group 'Pharmacognosy and Phytotherapy', UCL School of Pharmacy, University of London, London, United Kingdom.
J Pharm Biomed Anal. 2024 Apr 15;241:115990. doi: 10.1016/j.jpba.2024.115990. Epub 2024 Jan 23.
The tuberous roots of Ophiopogon japonicus and Liriope spicata are used for the same therapeutic purpose in traditional Chinese medicine and are collectively referred to as maidong medicine. Interestingly, it was observed that the price of tuberous roots varies depending on their location on the plant, and fibrous roots are usually discarded post-harvest. Mislabeling might be of concern due to similarities in morphological features between the two species. Moreover, paclobutrazol has been observed to be heavily applied during the production, and therefore might be of health concern. Overall, maidong might suffer from quality inconsistencies while its metabolomic complexity is influenced by growing region and cultivation practices, botanical species, and plant parts. To address these challenges, this study employed High-Performance Thin Layer Chromatography (HPTLC) approach, in which sample preparation and derivatization procedure were optimized to enable to capture more detailed and comprehensive metabolomic fingerprints. By integrating with rTLC algorithm and Multivariate Data Analysis (MVDA), an improved quality assessment was achieved. Samples were collected from four production regions and supplemented with commercial products from markets. The optimized HPTLC analysis recognized species- and region-specific metabolomic patterns of maidong, uncovering a 4% of mislabelled cases. Moreover, findings highlight the underexplored therapeutic potential of fibrous roots, and comparable therapeutic efficacy between different root types. Additionally, complemented by Liquid Chromatography-Mass Spectrometry (LC-MS) for paclobutrazol residue evaluation, 24.66% of the commercial maidong samples surpassed maximum residue limits of paclobutrazol, raising safety concerns. This research represents a significant analytical advancement, offering a robust, cost-effective, and comprehensive method for maidong quality control, and paving the way for more strict residue regulation and updates to herbal pharmacopoeias and monographs.
麦冬药材是百合科沿阶草属植物麦冬（Ophiopogon japonicus）和山麦冬（Liriope spicata）的干燥块根，具有相同的药用功效，在中医药中被统称为麦冬。有趣的是，人们观察到麦冬块根的价格会因其在植物上的位置而有所不同，而且通常在收获后会丢弃纤维状的根。由于这两个物种在形态特征上相似，因此可能存在标签混淆的问题。此外，在生产过程中观察到大量使用了多效唑，这可能对健康造成影响。总的来说，麦冬可能存在质量不一致的问题，同时其代谢组学的复杂性受到生长区域和栽培方式、植物种类和植物部位的影响。为了解决这些挑战，本研究采用了高效薄层色谱（HPTLC）方法，对样品制备和衍生化程序进行了优化，以捕捉更详细和全面的代谢组指纹图谱。通过与 rTLC 算法和多变量数据分析（MVDA）相结合，实现了改进的质量评估。从四个生产区域采集了样品，并补充了市场上的商业产品。优化后的 HPTLC 分析识别出了麦冬的物种和区域特异性代谢组学模式，发现了 4%的标签错误案例。此外，研究结果还揭示了纤维状根的未被充分探索的治疗潜力，以及不同类型根之间相当的治疗功效。此外，通过液相色谱-质谱联用（LC-MS）评估多效唑残留量，发现 24.66%的商业麦冬样品超过了多效唑的最大残留限量，引起了安全问题的关注。本研究代表了分析方法的重大进展，为麦冬质量控制提供了一种强大、经济有效的综合方法，并为更严格的残留量监管以及草药药典和专论的更新铺平了道路。
