香菇於化學及細胞平台之抗氧化能力探討

Abstract

近年來有許多的研究致力於尋求具有抗氧化性且安全無毒害之天然物以降低生物體內之氧化性傷害。菇類當中具有許多功能性成分，特別是其中的多醣體已經被廣泛的研究其與保健功能之間的關聯性。目前已有許多的文獻指出菇類當中的多醣體具有降血糖、降膽固醇、抗炎症、抗菌、降低氧化傷害、增加傷口癒合、增加肝功能、抗腫瘤作用和免疫刺激等生物活性。此篇論文的重點在於建立化學性以及生物性的抗氧化實驗平台，並以Lentinula edodes之發酵濾液及多醣體萃取液作為樣品。本實驗利用具有相進同源性的十株香菇（Lentinula edodes）菌株L1 , L4 , L6 , L10 , L11 , L15 , L21 , L23 , L24 和L25做為材料。 體外抗氧化活性測試的方法分別為：抗氧化力-共軛雙烯法、還原力、對DPPH自由基的清除能力、對金屬亞鐵離子的螯合能力。L21在抗氧化能力(81.66%)以及亞鐵離子螯合能力(82.25%)皆有優異的表現。還原力項目中表現最好的是L15(0.88)。L6(75.75%)在DPPH清除能力是最強的。 本論文的突破在於建立一套細胞內的抗氧化實驗平台。嘗試以過氧化氫模擬生物體內的氧化系統，探討修復能力以及防護能力。以鼠肝細胞(Clone-9;CRL-1439)為平台嘗試了解細胞內抗氧化酵素複雜的表現。結果顯示，修復能力：顯示L15和L25多醣萃取液濃度越高效果越好但整體差異性不高，但與維生素C與E相當。保護能力：L25表現優於L15，L25顯著的表現出多醣濃度越高保護能力越好甚至超越維生素C與E，發酵濾液的保護能力也有優越的表現。在細胞抗氧化保護能力大於修復能力。總體而言我們成功的建立了細胞內抗氧化實驗的平台，並且證實發酵濾液以及香菇多醣萃取液在化學系統以及生物系統都確實具有抗氧化能力。

Recently, there is increasing interest in finding natural antioxidants from plants, which protect human body against free radicals insult and ameliorate the progress of many chronic disease. Polysaccharide, in particular , is supposed to be responsible for some healthy properties of mushrooms. In this study, the ultimate goal was to establish a method for analyzing antioxidant activities on chemical and biological system of polysaccharide from Lentinula edodes culture broth filtrate. Ten isolates of Lentinula edodes , including L1 , L4 , L6 , L10 , L11 , L15 , L21 , L23 , L24 and L25 , were investigated .The antioxidant assays include: reducing power, α, α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging effect, Fe2+ chelating power and the antioxidant activity by the conjugated diene method. The Lentinula edodes culture broth filtrate result showed that L21 had the best antioxidant active (81.66%) and chelating effect on ferrous ions (82.25%).The reducing powers were good at L15 (0.88). The DPPH scavenging effect was good at L6 (75.75%). The breakthough of this study was to build up an intracellular biological antioxidant model.This study tryied to use hydroxyl peroxide to animate biological oxidative system and discuss the repair power and the protection power. The Clone-9 CRL-1439 were as used model to understand the complicated expression of the intracellular antioxidant enzyme.The result should that the protection power was more significant the repair power. The study of repair Power Indicates L15 and L25 having better performance in high concentration, about the same with VIt C and Vit E. The study of protection Power showed the expression of L25 was better than L15, In high polysaccharide concentration the L25 was remarkable to have better protection ability , even better than Vit C and VIt E.Culture broth filtrate also has good protect performance. To summarize, this syudy truly built up an intracellular biological antioxidant model and showed that both culture broth filtrate and hot-water extract of polysaccharide were antioxidantive in chemical system and biological system.