生鮮何首烏抗氧化成分及特性探討   全文下載

Potential Antioxidant Components and Characteristics of Fresh Polygonum multiflorum

本研究分析何首烏之葉、莖與根所含具生物活性化合物之含量，並藉由自由基清除試驗及抗氧化物質之偵測探討其抗氧化活性。三個不同部位，包括根、莖與葉水萃物具抗氧化能力之總酚含量依序為179.0、70.3及118.0 mg/g，而類黃酮為7.3、8.0及37.5 mg/g。進一步以HPLC分析此功能性植物葉與莖quercetin含量，分別為13469及1095 mg/kg。此外，根與莖含多量之emodin，其分別為6620及1245 mg/kg。顯示根、莖與葉因含不同量之emodin及quercetin而有不同程度之抗氧化能力。本研究發現DPPH自由基清除能力、總抗氧化活性（TEAC）、還原力及NO清除活性為根 > 葉 > 莖，而超氧陰離子之清除效應為莖 > 葉 > 根。此外，上述結果顯示此何首烏三部位萃取物清除自由基之活性優於emodin及quercetin標準品。然而，何首烏富含之emodin 相關化合物及quercetin，顯示這些化合物在抗氧化效應扮演關鍵性的角色。綜合以上結果，何首烏之抗氧化效應主要與emodin相關化合物及quercetin有關。

The leaf, stem and root of fresh Polygonum multiflorum plant were investigated. The contents of bioactive compounds and their antioxidant potential were studied by several radicals scavenging assay, and the antioxidative substances measured. The total phenolic contents were 179.0, 70.3 and 118.0 mg/g, whereas flavonoids contents were 7.3, 8.0 and 37.5 mg/g for water extracts from root (R), stem (S) and leaf (L), respectively. Further HPLC analysis revealed that the leaf and stem of this functional plant contained quercetin at 13,469 and 1,095 mg/kg, respectively. Furthermore, the root and stem contained rich emodin-related compounds that were 6,620 and 1,245 mg/kg, respectively. And different concentrations of emodin-related compounds and quercetin in root, stem and leaf showed different antioxidative ability. We observed that the DPPH scavenging activity, total antioxidant activity (TEAC), reducing power and NO scavenging ability of the three parts of the plant samples and found that the activities were R > L > S except that was S > L > R on superoxide anion scavenging effect. Our results indicated that the radical scavenging abilities of the three sample parts were more potent than that of emodin and quercetin. P. multiflorum contains rich emodin-related compounds and quer-cetin, indicating that these compounds played important roles in antioxidative effect. We suggested that the antioxidative effect of the fresh P. multiflorum plant correlate-well with emodin-related compounds and quercetin.