相思樹材部酚類化合物與抗氧化活性之縱向及徑向變異

LONGITUDINAL AND RADIAL VARIATIONS OF PHENOLIC CONTENTS AND ANTIOXIDANT ACTIVITIES IN ACACIA CONFUSA

黃于庭(Yu-Ting Huang) ； 陳育涵(Yu-Han Chen) ； 葉汀峰(Ting-Feng Yeh) ； 顏佩翎(Pei-Ling Yen) ； 張上鎮(Shang-Tzen Chang)

《中華林學季刊》 48卷3期 (2015/09) Pp. 251-262

摘要

相思樹(Acacia confusa Merr.)為臺灣本土樹種，為了解相思樹縱向及徑向之生物活性差異，本研究將單株相思樹由基部至樹頂依高度分為4區段，而各區段再由髓心往邊材以每7個年輪數分為5個區塊，以乙醇萃取其抽出物，並分別測定總酚類化合物含量和總黃酮類化合物含量，再以清除DPPH自由基、清除超氧自由基及抑制黃嘌呤氧化酶試驗評估其生物活性。試驗結果顯示，靠近木材基部之總酚類化合物與總黃酮類化合物含量最高，縱向之含量分布則隨高度增加而遞減；至於徑向變化，總酚類化合物於移行材之含量最高，而總黃酮類化合物含量則由邊材向髓心遞增。心材各區塊抽出物清除DPPH及超氧自由基之結果，不論縱向或徑向皆無顯著差異；基部之內層心材抽出物抑制黃嘌呤氧化酶之活性最佳。上述3種活性皆與總酚類化合物及總黃酮類化合物含量成正相關，其中又以抑制黃嘌呤氧化酶之活性與總黃酮類化合物含量具有高度相關性。

關鍵字

相思樹 ； 抗氧化活性 ； 縱向分布 ； 徑向分布 ； 移行材 ； 黃嘌呤氧化酶

並列摘要

Acacia confusa Merr. is an indigenous tree species in Taiwan. The objective of this study was to investigate the variations of bioactivities between longitudinal and radial wood in A. confusa. Four sections were taken from the base to the top of the tree. Each section was divided into five blocks by every seven tree rings from pith to sapwood. All specimens were extracted with ethanol, and their bioactivities were evaluated by DPPH radical, superoxide radical scavenging assays and xanthine oxidase (XOD) inhibitory activity. In addition, total phenolic contents (TPC) and total flavonoid contents (TFC) were also examined. Results showed that the TPC and TFC of wood extracts were the highest at the tree base, and these contents decreased from the base toward the top at longitudinal distribution. The highest amount of TPC was at transition zone, and TFC gradually increased from sapwood toward pith at radial distribution. No significantly statistical difference on DPPH radical and superoxide radical scavenging activities of all heartwood extracts was observed regardless of longitudinal or radial direction. However, the best XOD inhibitory activity was in inner heartwood extracts. These three activities mentioned above were positive correlated with TPC and TFC. Among them, the XOD inhibitory activity was highly positive correlated with TFC.

並列關鍵字

Acacia confusa ； antioxidant activity ； longitudinal distribution ； radial distribution ； transition zone ； xanthine oxidase