Study on Fingerprints of Traditional Chinese Medicine Processing Accessories of Rice Vinegar

OBJECTIVE To provide the basis for the medicinal quality standard of Chinese medicine processing accessories of rice vinegar through analysis with fingerprints of different kinds of origin and brand of rice vinegar. METHODS 33 batches of vinegar were collected. The mobile phase， column， elution， the mobile phase pH were investigated and the analysis method of HPLC fingerprint was optimazated， Among them， 20 batch of rice vinegar fingerprint were chosen to perform the similarity， cluster analysis and principal component analysis. RESULTS The concentration of rice vinegar was diluted at 1∶3 when it was injected. Chromatographic column was Thermo Hypersil GOLD （5 μm，250 mm×4.6 mm）; the mobile phase was composed of methanol and 0.07% phosphoric acid aqueous solution and a gradient elution program at flow rate of 1 mL/min was applied. The column temperature maintained at 30 ℃. The injection volume was 10 μL. Then， the separation of characteristic peaks was optimum. Rice vinegar was divided into black vinegar and white vinegar. Furthermore， there was a big difference between black vinegar and white vinegar. The white vinegar almost showed only one peak of acetic acid， so， it's impossible to distinguish between brewing white vinegar and formulated white vinegar by HPLC. Similarity evaluation showed that 20 batch of white vinegar's fingerprints had palpable difference. Besides， clustering analysis and principal component analysis splited them into several categories. Different types of Hengshun vinegar indicated high similarity. Hence it could be seen that the quality of rice vinegar from the same brand was uniform and stable because of similar brewing processes and similar materials . CONCLUSION There are varieties of rice vinegar on the market with extensive source and uneven quality. 20 batches of black rice vinegar were chosen to compare the differences by HPLC fingerprints analysis， which provides reference for the medicinal quality control standard of traditional Chinese medicine processing accessories of rice vinegar.