Antioxidant and anti proliferative activities of the four Hydrocotyle species from Taiwan

作者：Huang Shyh Shyun; Huang Guan Jhong; Ho Yu Ling; Lin Yaw Huei; Hung Hsin Jung; Chang Tien Ning; Chang Man Jau; Chen Jial Jhen; Chang Yuan Shiun^*

来源：Botanical Studies, 2008, 49(4): 311-322.

• Antioxidant
• Antiproliferative
• Free radical
• Flavonoid
• Hep3B
• Hydrocotyle
• Polyphenol

The aim of this study was to examine the possible antioxidant and antiproliferative activities of the ethanol and water extracts of four Hydrocotyle species from Taiwan. ABTS radical monocation scavenging, FRAP method, DPPH radical scavenging, reducing power method, total polyphenol content, total flavonoid content, total flavonol content, and inhibition of cancer cell proliferation methods were employed. The results showed that the water extracts of all the samples had higher antioxidant and antiproliferative activities than the ethanol extracts. All tested extracts were weaker than the positive controls (BHT and GSH) in the antioxidant activity. We also found that the water extracts of all the samples had higher content of polyphenol compounds, but lower content of flavonoid compounds than the ethanol extracts. In ABTS radical scavenging assay, the TEAC (trolox equivalent antioxidant capacity) values of the water extracts samples were in descending order: H. nepalensis (HN) > H. setidosa (HSe) > H. batrachium (HB) > H. sibithorpioides (HSi). The correlation coefficient (R(2)) values of TEAC and total polyphenol content showed a higher correlation (water extracts, R(2)=0.934; ethanol extracts, R(2)=0.904). The R(2) values of TEAC and total flavonoid content for the water and ethanol extracts were 0.995 and 0.785 respectively. The R 2 values of TEAC and FRAP also showed a higher correlation (water extracts, R(2)=0.984; ethanol extracts, R(2)=0.971). In HPLC analysis, the chromatograms of the water and ethanol extracts of HN with the highest antioxidant activity were established. Rutin might be an important bioactive compound in HN extracts. The antiproliferative activities of the four Hydrocotyle species were Studied in vitro using human hepatoma Hep3B cells, and the results were consistent with their antioxidant capacities. The water extract of HN had the highest antiproliferative activity with an IC(50) of 435.88 +/- 8.64 mu g/mL. The ethanol extracts of HB and HSi had the lowest antiproliferative activities (IC(50) > 2000 mu g/mL) under the experimental conditions. We suggested that HN might be served as a good source of natural antioxidant among the Hydrocotyle genus.

• 出版日期2008-10
• 单位中国医科大学