Monosaccharide compositions of Codonopsis pilosula polysaccharides and their correlation analysis on cytotoxic activities against HepG2 cells / 中草药

ABSTRACT

Objective: To study the correlation between monosaccharide compositions and their in vitro cytotoxic activities. Methods: Twenty-six Codonopsis pilosula polysaccharides (CPPs) were extracted by water extraction and alcohol precipitation method from C. pilosula collected from 26 different habitats. Total carbohydrate contents of the polysaccharides were determined by the phenol-sulfuric acid colorimetric method. The methods of m-hydroxydiphenyl and GC were all applied to the determination of the galacturonic acid contents in polysaccharides, and the compositional analysis was performed using the aldononitrile acetate method while the fructose contents was analyzed by the trimethylsilyl ether method. In vitro cytotoxic activities against human hepatocellular carcinoma HepG2 cells of the 26 batches of CPPs were evaluated by MTT. Then, hierarchical clustering analysis (HCA) was used to study the classification of 26 batches of C. pilosula and partial least squares (PLS) was used to investigate the correlation between the monosaccharide compositions and in vitro cytotoxic activities of the polysaccharides. Results: The results showed that all the 26 batches of CPPs possessed the cytotoxic activities against HepG2 cells. The 8th CPPs sample, which was extracted from the C. pilosula collected in Wen county (Gansu province, China), had the highest growth inhibitory rate on HepG2 cells and the inhibitory rate was 36.36%. In addition, the monosaccharide contents of the 26 batches of CPPs were different from each other. The results of HCA showed that the C. pilosula could not be classified according to the monosaccharide compositions. The PLS results indicated that galacturonic acid, arabinose, rhamnose, galactose, and fructose were correlated positively with the cytotoxic activities, while mannose, xylose, and glucose were correlated negatively with the cytotoxic activities. Conclusion: The in vitro cytotoxic activities of CPPs are highly correlative to their monosaccharide compositions, and the CPPs containing much galacturonic acid have the obviously cytotoxic activities.