In a study published in analytical science journal Analytica Chimica Acta, Hong Kong Polytechnic University (PolyU) detailed a new and improved method for the identification and authentication of Chinese herbal medicines.
Developed by the Food Safety and Technology Research Centre — under PolyU's Department of Applied Biology and Chemical Technology — the new method is said to be able to analyse a single raw sample in 10 minutes, thereby identifying genuine and counterfeit species of herbs.
This makes for a far less laborious and time-consuming process than the conventional method of fingerprint chromatography, which requires a single sample to go through a few hours of preparation and separation.
Countering counterfeiting
This is especially important for the mushroom species Ganoderma or lingzhi, and Gastrodiae Rhizoma or tianma, two of the most popular and rare Chinese herbal medicines, making their counterfeiting and adulteration fairly common.
Moreover, there are more than 80 species of lingzhi, but only two — chizhi and zizhi — are used in the medicine. Due to the sheer number of species and the close resemblance among some of them, confusion with the two officially used species is commonplace.
Tianma faces a similar issue, with two counterfeit species, Canna edulis Ker and Cacalia davidii (Franch.) Hand-Mazz, often mistaken for tianma.
The PolyU team revealed that the new method uses direct ionisation mass spectrometry (DI-MS) to identify the major active components of both medicines (ganoderic acids in lingzhi, and gastrodin and parishins in tianma).
This involves subjecting a raw sample to a direct high voltage after covering it in solvents, therefore inducing spray ionisation to produce mass spectra in a matter of minutes, and aiding in identification.
The medicines' major active components then allow for the differentiation of genuine samples from counterfeit samples.
Other outcomes of the new method include being able to categorise wild and cultivated herb species, and to determine their geographical origins, both via the dataset analytic tool PCA (Principal Component Analysis).
According to PolyU, its new method can easily be reproduced by other researchers in the area of herbal medicines, since they would not need any new or specialised devices to do so.
Clamouring for credibility
The TCM industry has been employing methods rooted in modern science to improve testing, so as to prove the efficacy of its products via scientific evidence.
Researchers have called for 'Q-markers' to affirm the safety and efficacy of TCM using "a more scientific quality-control approach" as more consumers express an interest in TCM.
The industry's credibility took a hit last year, when it was revealed that many TCM products were rife with adulteration. Analysts had discovered over 1,200 adulterants in proprietary Chinese medicines, many of which could trigger adverse effects such as psychosis and hypoglycaemia.
Certifying the safety and efficacy of TCM is especially crucial in a time when an increasing number of supplement firms are looking to incorporate its elements into their products.
Before leaving the Australian supplement giant, former Blackmores CEO Christine Holgate had praised TCM, saying the company had "a lot to learn from the Chinese about the use of herbs in medicine".
Furthermore, the rising interest in TCM was reflected in its 20% growth in China last year, bringing it past the $130bn mark amid stricter regulations being introduced for aspiring TCM practitioners in the country.
Source: Analytica Chimica Acta
http://dx.doi.org/10.1016/j.aca.2016.07.028
"Rapid authentication of Gastrodiae rhizoma by direct ionization mass spectrometry"
https://doi.org/10.1016/j.aca.2017.11.006
"Rapid differentiation of Ganoderma species by direct ionization mass spectrometry"
Authors: Ho-Yi Wong, et al.