Colla corii asini (CCA) is a very famous traditional Chinese medicine (TCM) for nourishing blood, replenishing yin, and moistening dryness [1]. Unfortunately the counterfeit gelatins made from other animal skins rather than donkey have emerged, which could lead to adverse drug or allergic reactions in patients . A specific method, taking one unique peptide for each animal species as the detection marker, was developed by Li, et al [2], which would control the counterfeit phenomenon effectively. However, the identification of authentic CCA [1] by taking one peptide as the marker lack specificity and it is obvious there is a potential risk that this peptide would be added in counterfeits directly . Therefore, it is still imperative to develop more effective and comprehensive identification method. In the study, peptidomic approach was applied by using nanoLC-Orbitrap HRMS to analyze the in-house-made donkey, mule and horse gelatins, which have highly consistent amino acid sequences for their collagen. The peptides identification was carried out by Proteome Discoverer software. As a result, 1 peptide was defined to be common for CCA and mule gelatins and 9 were simultaneously detected in CCA, mule and horse gelatins. Subsequently, a characteristic profile was developed by taking the 10 peptides as the quality markers (Q-marker) using LC-MS/MS with MRM mode. This method was verified to be specific for the 10 markers were not detected in the gelatins made from cattle, sheep, and pig skins. The quantification results suggested that the total content ranged from 1.04%% to 2.11% with little difference for all the samples. Principal component analysis based on the content showed that the three kinds of gelatins could be differentiated apparently . The proposed method, involving both the qualitative and quantitative aspects, should play a significant role in standardizing and providing quality control to CCA market.
Key words: Colla corii asini; peptidomic analysis; Q-marker; nanoLC-Orbitrap HRMS; LC-MS/MS
Rerefence
[1] China Pharmacopoeia Committee. Pharmacopoeia of the People’s Republic of China. China Chemical Industry Press; 2015: 189.
[2] Li X, Shi F. Int J Nanomed 2017; 12: 4443–4454.