ABSTRACT
OBJECTIVE To establish the fingerprints of dried Houttuynia cordata and its decoction pieces ,conduct chemometrics analysis and determine the contents of 5 flavonoids such as neochlorogenic acid. METHODS High performance liquid chromatography (HPLC)method was adopted. Using quercitrin as reference ,HPLC fingerprints of 10 batches of dried H. cordata and its decoction pieces were drawn. The similarity evaluation was conducted by Similarity Evaluation System of TCM Chromatographic Fingerprint (2012 edition),the common peaks were also confirmed. SIMCA-P 14.1 software was applied for principal component analysis (PCA)and partial least square-discriminant analysis (PLS-DA),and the variable importance in projection(VIP)value more than 1 was considered as a standard to screen the differential components affecting the quality of these two products ;meanwhile,the contents of 5 components such as neochlorogenic acid in both products were determined by the same HPLC method. RESULTS There were 20 common peaks in 10 batches of dried H. cordata and 10 batches of its decoction pieces with the similarity values more than 0.960. A total of 5 common peaks were identified ,which were neochlorogenic acid (peak 1), chlorogenic acid (peak 3),cryptochlorogenic acid (peak 4),rutin(peak 7)and quercitrin (peak 11). The results of PCA and PLS-DA showed that dried H. cordata could be distinguished from its decoction pieces obviously ;the common peaks with VIP value greater than 1 were as follows :peak 7(rutin),peak 20,peak 5,peak 13,peak 2,peak 18,peak 3(chlorogenic acid ), peak 14,peak 17 and peak 19. The linear range of neochlorogenic acid ,chlorogenic acid ,cryptochlorogenic acid ,rutin and quercitrin were 3.77-60.29 μg/mL(r=0.999 7),1.40-22.42 μg/mL(r=0.999 5),3.76-60.22 μg/mL(r=0.999 9),2.19-35.06 μg/mL (r=0.999 9)and 25.49-407.88 μg/mL(r=0.999 7),respectively. RSDs of precision ,stability(24 h)and reproducibility E-mail:20190394@njucm.edu.cn tests were all lower than 3%. The average recoveries of the above components in these two products were 98.72%-101.12% and 98.86% -100.63% with RSDs less than 3%(n=9). In dried H. cordata ,the average contents of 5 components were 0.87,0.33,0.59,0.61 and 6.17 mg/g,while the average contents were 0.42,0.11,0.26,0.23 and 3.16 mg/g in its decoction pieces ,respectively. CONCLUSIONS HPLC fingerprint and the method of content determination are stable and feasible ,which could be used for the quality control of dried H. cordata and its decoction pieces. Besides ,rutin and other components may be the differential components which could affect the quality of these two products ;the average contents of the 5 flavonoids such as neochlorogenic acid in dried H. cordata all decrease after processing.
ABSTRACT
OBJECTIVE To establish the method for monitoring the dynamic changes of odor components in Cornus officinalis during processing . METHODS The decoction pieces of C. officinalis with different processing time were prepared by the wine steaming method . The dynamic changes of odor components were obtained by using ultra -fast gas electronic nose ;odor components were identified by comparing with AroChemBase database ;the dynamic changes of odor compounds were analyzed in combination with peak area ,and the chemical pattern recognition analysis were carried out . RESULTS A total of 12 common peaks of odor components were identified in the fingerprints of raw C. officinalis,and 21 in the fingerprints of decoction pieces of C. officinalis. Eight odor components with the high proportion of peak area during processing were ethanol , isopropyl alcohol , 2- methylpropylaldehyde,ethyl acetate ,2-methylbutanal,isoamyl alcohol ,2-hexanol and furfural ,among which ,the peak areas of ethanol,isoamyl alcohol and 2-hexanol showed a trend of first increasing and then decreasing ;at 24 h of processing ,their peak areas were still higher than those of raw products . The peak areas of ethyl acetate ,2-methylbutanal and furfural nearly increased with the increase of processing time . Variable importance in projection of above eight odor components were all greater than 1. CONCLUSIONS The method is established for monitoring the dynamic changes of odor components of C. officinalis during processing. Eight odor components such as ethanol can be used as monitoring indicators of C. officinalis dring processing .