| 摘要: | 本研究的主要目的為利用抗氧化活性篩選目標分離方法，進行南嶺前胡花蕾抗氧化成分之分離。
南嶺前胡（Peucedanum longshengense, PL）為1986年發現之繖形科（Apiaceae）新品種，其植物組織顯微鑑定及其花蕾部位之藥理活性目前尚未曾有文獻報告，故本研究針對南嶺前胡之根、莖、枝、葉等各部位，利用組織切片，建立其顯微組織鑑定圖譜。並於開花期取其新鮮花蕾（2.43 kg），切碎後以乙醇在室溫下浸泡萃取，過濾濃縮乾燥後，可得乙醇萃取物（PLE）。再分別利用CH2Cl2、n-BuOH及H2O等溶媒進行分配萃取，濃縮乾燥後分別可得PLEC、PLEB及PLEW等萃取層，並將各萃取層及乙醇萃取物以DPPH自由基清除能力及Trolox當量抗氧化能力試驗平台進行抗氧化能力試驗。結果顯示PLEB具有最佳的DPPH（2,2-diphenyl-1-picrylhydrazyl）自由基清除能力及Trolox當量抗氧化能力。
將最具抗氧化活性之PLEB，進行逆相管柱層析分離，可得到PLEB1～7共七個分層，再利用抗氧化篩選平台進行篩選較具抗氧化能力之分層，所得實驗結果顯示PLEB3具有最佳的抗氧化活性。將PLEB3進行逆相管柱層析分離，共得到PLEB3-1～3-8共八個分層及一結晶物質PLEB3-5C，再將各分層進行抗氧化能力試驗分析，結果顯示PLEB3-7為具有最佳之抗氧化活性，其抗氧化活性成分需再進一步分析。
另外結晶物PLEB3-5C 經各種光譜分析後，並與標準品比對構造，鑑定為p-Hydroxycinnamic acid。
The purpose of this study is to isolate the antioxidant constituents from the buds of Peucedanum longshengense according to the antioxidative activity – guided isolation process.
Peucedanum longshengense (PL) is a new species of Apiaceae that was found in 1986. Because there is no report about the microscopic tissues identification and pharmacological activities of the buds of PL, this study focused on the roots, stems and leaves to establish the microscopic tissues identification spectrum. The fresh buds (2.43 Kg) were collected and powdered, and were extracted with 95% EtOH at room temperature. After three months, 95% EtOH extracted solution was filtrated, the EtOH solution was removed by a rotary evaporator, and crude extract (PLE) was obtained. PLE was partitioned with CH2Cl2, n-BuOH and H2O solvents, respectively. Three layer extracts, namely, PLEC, PLEB and PLEW extracts were obtained, and PLE, PLEC, PLEB and PLEW were determined by the antioxidant activity assays of DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals scavenging activity and Trolox equivalent antioxidant capacity (TEAC) analyses. The results showed that the most potent antioxidant layer was PLEB.
PLEB was subjected to a reverse phase column chromatography, and seven fractions, including PLEB1～7, were obtained. They were also evaluated by the antioxidant activity assays. All results showed that the PLEB3 had the most effective antioxidant activity.
PLEB3 was subjected to a reverse phase column chromatography. Eight fractions, PLEB3-1～3-8, and a crystal, PLEB3-5C, were collected, and they were also evaluated by antioxidant activity analyses. The antioxidant constituents of PLEB3-7 will need to be isolated and identified.
PLEB3-5C was elucidated to be p-hydroxycinnamic acid using spectrometry analysis and comparing with authentic sample of p-hydroxycinnamic acid. |
