海藻海龍鬚菜萃取物之生物活性評估

Assessment of bioactivities of algae extracts from Gracilaria sp.

葉紀禎(Chi-Chen Yeh)

指導教授 ： 張學偉

高雄醫學大學/藥學院/毒理學碩士學位學程/博士(2014年)

摘要

現今已有的文獻報導海藻拿來當作保健食品的應用，以及做了很多有關人體健康影響之功能性研究。在近年來研究上，海藻對於細胞代謝的效果已經被發現能調節體內和體外的抗氧化系統、活性氧原的代謝，以及癌症細胞凋亡。
海藻海龍鬚菜Gracilaria tenuistipitata之甲醇萃取物(MEGT)之抑制癌細胞增生作用，對抵抗口腔鱗狀癌細胞Ca9-22 (oral squamous cell cancer; OSCC)，依造細胞生長與細胞週期的改變、細胞凋亡、活性氧原、穀胱甘肽含量，以及粒線體膜電位而言來探討，確定它的潛在作用機制。海藻海龍鬚菜Gracilaria tenuistipitata之乙醇萃取物(EEGT)也能夠藉由細胞內活性氧原的增加、穀胱甘肽減少、細胞凋亡蛋白酶的活化，以及粒線體去極化，來誘導口腔鱗狀癌細胞Ca9-22之生長抑制和細胞凋亡。
在先前的研究上，海藻海龍鬚菜Gracilaria tenuistipitata之水萃取物(AEGT)，已被證實具有潛在抗氧化物以及活性氧原的調節者，然而由於仍處於粗萃取物的本質會限制它後續深入的發展性，因此，進行液相-液相的溶劑分離萃取法變成三種不同溶劑的AEGT分離萃取物質，分別為乙酸乙酯層(AEGT-pEA)、正丁醇層(AEGT-pBuOH)、水層(AEGT-pW)，被分離後續評估它們的總酚含量和總類黃酮含量、以及2,2-二苯基-1-苦味肼基(2,2-diphenyl-1-pi-crylhydrazyl；DPPH)自由基清除能力、2,2'-聯氮雙(3-乙基苯並噻唑??-6-磺酸) (2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid)；ABTS)自由基清除力、鐵離子的還原力、亞鐵離子的螯合能力。我們進行液相-液相的溶劑分離方式，去萃取AEGT變成三種具有潛力之溶劑分離萃取物，與未經過溶劑分離法之AEGT相比，抗氧化能力顯得更強。

關鍵字

海藻 ； 海龍鬚菜 ； 活性氧原 ； 穀胱甘肽抗氧化物 ； 口腔鱗狀癌細胞 ； 細胞凋亡 ； 粒線體

並列摘要

The existing literatures have reported applications of algae for nutraceuticals and several functions for affecting human’s health. In current research, the effects of algal extract on cells metabolism have been found to regulate in vivo and in vitro antioxidant system, reactive oxygen species (ROS) metabolism and cancer cell apoptosis.
The anticancer proliferative effect of methanolic extract of Gracilaria tenuistipitata (MEGT) against the human oral squamous cell cancer (OSCC) Ca9-22 cell line was explored in terms of the cell viability and the alterations of cell cycle, apoptosis, ROS, glutathione (GSH) content, and mitochondrial membrane potential (MMP) to determine its possible mechanism of action. The ethanolic extract of G. tenuistipitata (EEGT) also induced the growth inhibition and apoptosis of OSCC Ca9-22 cell line, which was accompanied by intracellular ROS generation, GSH depletion, caspase activation, and mitochondrial depolarization.
In our previous study, the potential antioxidant and cellular ROS modulator of aqueous extract of G. tenuistipitata (AEGT) have been demonstrated; however, the crude extract limits its further application. Therefore, we processed liquid-liquid solvent partitioned extraction into three different solvents-partitioned extracts of AEGT, namely ethyl acetate (AEGT-pEA), n-butanol (AEGT-pBuOH) and distilled water (AEGT-pW). We separately evaluated its total phenol (TPC), total flavonoid content (TFC), antioxidant activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, ferric ion reducing antioxidant power, and ferrous ion-chelating ability. Finally, we performed the liquid-liquid solvent partition to further separate the AEGT into potential partitions with more abundant antioxidant property than the AEGT without partition.

並列關鍵字

algae ； Gracilaria ； reactive oxygen species ； glutathione ； antioxidant ； oral squamous cell cancer ； apoptosis ； mitochondria

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