http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/95 2026-03-09T02:09:41Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/35167 標題: 龍眼花萃取物抗氧化性之探討; Studies on the Antioxidative Activities of Longan (Dimorcarpus longan Lour.) Flower Extracts 作者: Yi-Jane Shen; 沈宜蓁 摘要: 近年來，許多慢性疾病的發生與氧化壓力具有很大的相關性，例如癌症、動脈粥狀硬化、老化等，當體內氧化物與抗氧化物不平衡時即會造成氧化傷害，因此需有足夠的抗氧化物質俾能抵抗氧化壓力的產生。本研究目的主要以抗氧化活性之化學檢測方法及體外生物活性檢測方法評估龍眼花不同溶劑粗萃物之抗氧化活性，期能找出具最佳抗氧化力的龍眼花粗萃物，並進一步分析龍眼花中提供抗氧化力之有效區分層及提供抗氧化力之可能有效成分，以提高龍眼花之利用價值。 本實驗龍眼花之萃取方式為沸點下熱水迴流萃取及室溫下以95%乙醇、甲醇、乙酸乙酯與正己烷四種溶劑之攪拌萃取。再以七種抗氧化活性評估方法檢測此五種龍眼花不同溶劑之粗萃物，包括清除DPPH自由基、TEAC (Trolox equivalent antioxidant capacity)、氧自由基吸收能力 (Oxygen radical absorbance capacity, ORAC)、還原力、抑制微脂粒 (liposome) 過氧化、抑制銅離子誘導低密度脂蛋白 (low density lipoprotein, LDL) 氧化與以TGF-β1 (transforming growth factor-β1) 誘導肝癌細胞Hep 3B產生氧化損傷之保護效果。 實驗結果顯示，龍眼花水粗萃物於各抗氧化實驗中皆展現較高之抗氧化力，其清除DPPH自由基之EC50為3.69±0.16 μg/mL，TEAC值為1.22 mM Trolox equiv.，ORAC值為7.28 mM Trolox equiv.，還原力方面於50 μg/mL時A700 =1.84，抑制微脂粒過氧化之IC50為54.46±1.61 μg/mL，且延緩銅離子誘導LDL氧化之效果最佳，為同濃度下Trolox之0.62倍；以TGF-β1誘導肝癌細胞Hep 3B產生氧化損傷實驗中，其於100 μg/mL濃度時達約64.3±3.4%的回復率。整體而言抗氧化活性以水粗萃物最佳，其次為甲醇、乙醇與乙酸乙酯粗萃物，而正己烷粗萃物則幾乎無抗氧化效果。 進一步分析龍眼花不同溶劑粗萃物之抗氧化成分，結果顯示，水粗萃物中的總酚類化合物 (548.2±12.7 mg gallic acid equivalent / g of dry weight) 與没食子酸 (10.4 ± 0.3 mg gallic acid /g of dry weight) 含量最多，因此推測其抗氧化力可能來自於龍眼花中之酚類物質。再進ㄧ步將龍眼花水萃物經Sephadex LH-20管柱層析分離得到八個區分層，並進行抑制銅離子誘導LDL氧化測定，結果以fraction 7之100%甲醇沖提區分層之效果最佳。本研究結果顯示龍眼花中提供抗氧化性的有效成分可能為一些極性較高的酚類物質。; Recently, many chronic diseases such as cancer, atherosclerosis, and aging were found to be associated with oxidative damage. The imbalance between the concentration of reactive oxygen and nitrogen species and defense mechanisms of the body would cause oxidative damage, and antioxidants enhancement would reduce oxidative damage. Therefore, dietary supplementation of antioxidants was thought to be beneficial to health. The purpose of this study is to locate the most antioxidative solvent extract of Longan (Dimorcarpus longan Lour.) flower by various antioxidative assays, and to further investigate the most efficient antioxidative fraction after chromatographic separation by the assay of Cu2+-induced low density lipoprotein (LDL) oxidation. First, the crude extracts were prepared by extracting Longan flower with boiling water and four solvents (95% ethanol, methanol, ethyl acetate and n-hexane) at room temperature. Then the five different solvent extracts of Longan flower were tested for various antioxidative assays, including DPPH free radical scavenging effect, Trolox equivalent antioxidant capacity (TEAC) assay, oxygen radical absorbance capacity (ORAC) assay, reducing power, inhibition of peroxidation in a liposome model system, Cu2+-induced oxidation of human LDL and recovery effect of TGF-β1 induced oxidative damage in Hep 3B cells. The results of antioxidative assays revealed that the best effect was exhibited by the water extract, followed by methanol, ethanol, ethyl acetate and n-hexane extracts of Longan flower. The EC50 value of water extract in scavenging DPPH radicals was 3.69±0.16 μg/mL. Results of TEAC and ORAC assays revealed that water extract gave the highest TEAC value (1.22 mM Trolox equivalent) and ORAC value (7.28 mM Trolox equivalent). With regard to reducing power, at sample concentration of 50 μg/mL, water extract gave the best effect. Concerning inhibition of peroxidation in a liposome model system, the IC50 of water extract in inhibiting the peroxidation was 54.46±1.61 μg/mL, which was the lowest among all the extracts. As for the effect of Cu2+-induced oxidation of human LDL, water extract showed the best effect in delaying LDL oxidation. Finally, water extract gave the best recovery effect of TGF-β1 induced oxidative damage in Hep 3B cells at concentration of 100 μg/mL. Water extract of Longan flower contained the most abundant amount of total polyphenol (548.2±12.7 mg gallic acid equivalent / g of dry weight) and gallic acid (10.4 ± 0.3 mg gallic acid /g of dry weight). According to the results of antioxidative assays, water extract showed the highest antioxidant capacity and we presumed that this could probably be related to the phenolic compounds. Then Sephadex LH-20 gel chromatography was employed to fractionate the water extract; eight fractions were obtained and tested for Cu2+-induced oxidation of human LDL. The result of antioxidative experiment revealed that fraction 7 showed the best effect in delaying LDL oxidation. We presumed that antioxidative capacity of Longan flower could probably be related to phenol compounds having higher polarity. 2005-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/28825 標題: 龍眼花水萃物對高果糖誘發代謝症候群大鼠之影響; Effect of Longan (Dimocarpus longan Lour.) Flower Water Extract on Metabolic Syndrome in Fructose-Fed Rats 作者: Hui-Yun Tsai; 蔡蕙芸 摘要: 代謝症候群是近年來受到重視的健康議題，其症狀包括高胰島素血症、胰島素阻抗、高三酸甘油酯血症和高血壓等，此些危險因子的叢聚現象與第二型糖尿病和心血管疾病有密切的相關性。前人研究也證實，於飲食中多攝取抗氧化物質有助於預防代謝症候群因而降低心血管疾病的發生。本研究室於先前的研究發現龍眼 (Dimocarpus longan Lour.) 花在體外具有很好的抗氧化活性，因此本研究目的在探討龍眼花粗萃物的高抗氧化活性是否能改善代謝症候群之諸多症狀。 實驗第一階段為體外抗氧化性試驗，先將龍眼花粉末分別以沸水萃取及室溫下以95%乙醇或甲醇溶劑攪拌萃取。再以兩種抗氧化活性評估方法，包括清除DPPH自由基能力試驗和抑制銅離子誘導人類低密度脂蛋白氧化檢測此三種不同溶劑之龍眼花粗萃物。實驗結果顯示，龍眼花水萃物於此二種抗氧化實驗中皆展現較高之抗氧化力，其清除DPPH自由基之EC50值為3.75±0.61 μg/mL，且延緩銅離子誘導LDL氧化效果為同濃度下正控制組trolox之1.57倍。整體而言抗氧化活性以水萃物最佳，其次為乙醇和甲醇萃取物。 第二階段為對大鼠進行急性灌食試驗，觀察龍眼花粗萃物對其耐糖能力的影響。急性試驗中，以龍眼花粗萃物125或250 mg/kg body weight (BW) 的劑量灌食正常Sprague-Dawley大鼠，同時進行口服葡萄糖耐受性試驗。結果顯示，大鼠灌食龍眼花水萃物250 mg/kg BW，在第30分鐘的血漿葡萄糖值顯著低於對照組，但胰島素濃度在各時間點則無顯著差異。此外，灌食龍眼花乙醇萃物125或250 mg/kg BW的劑量，不論在血漿葡萄糖或胰島素濃度與對照組比較皆無顯著差異。顯示大鼠急性灌食龍眼花水萃物可以減緩血糖上升的速度，其作用不在於改善胰島素敏感性，可能與延緩或干擾腸道對糖分的吸收有關。 第三階段為長效性試驗，以高果糖飼料誘發大鼠產生代謝症候群，觀察龍眼花水萃物是否能改善其症狀。將體重約250克Sprague-Dawley大鼠隨機分為4組：C組給予標準飼料；F組給予高果糖飼料；L組除了高果糖飼料外，每隻每天灌食龍眼花水萃物 125 mg/kg BW，為低劑量組；H組除了高果糖飼料外，每隻每天灌食龍眼花水萃物 250 mg/kg BW，為高劑量組，C組與F組則以灌食去離子水作為對照。實驗期為14週。F組自第2週起，收縮壓、禁食狀態血漿三酸甘油酯和胰島素皆明顯開始上升，但血漿葡萄糖濃度仍維持正常；於第4週進行口服葡萄糖耐受性試驗，已有胰島素阻抗之情況發生，顯示長期餵飼高果糖飼料已明顯誘導大鼠產生代謝症候群之症狀。在體內抗氧化能力試驗中，餵飼高果糖飼料14週後，會造成體內氧化壓力增加，血漿脂質過氧化物TBARS濃度明顯上升且肝臟抗氧化酵素活性下降。 給予低劑量125 mg/kg BW龍眼花水萃物的組別，可降低高血壓，於實驗11和12週血壓已明顯低於F組。在胰島素敏感性方面，於4、8和12週的口服葡萄糖耐受性試驗中，有改善胰島素阻抗的現象，但效果並不明顯。對於禁食血漿三酸甘油酯濃度仍不具有調節作用。在體內抗氧化能力試驗中可提升肝臟抗氧化酵素Glutathione reductase的活性，而在血漿脂質過氧化物TBARS濃度則無差異。 給予高劑量250 mg/kg BW龍眼花水萃物的組別，降血壓效果顯著，於實驗第7週開始已明顯低於F組。在胰島素敏感性方面，於第4週口服葡萄糖耐受性試驗中即開始有改善胰島素阻抗之現象。而給予高劑量的龍眼花水萃物仍無法降低禁食血漿三酸甘油酯濃度。在體內抗氧化能力試驗中可提升肝臟抗氧化酵素Glutathione reductase的活性，且可降低血漿脂質過氧化物TBARS的濃度。 分析脂肪細胞胰島素訊息傳遞相關蛋白質表現量的結果顯示，給予高果糖飼料會造成insulin receptor substrate (IRS-1)、Akt和glucose transporter 4 (GLUT 4)表現量降低，導致胰島素受體對胰島素之敏感性降低。而給予低劑量龍眼花水萃物14週後有增加IRS-1的表現量，而給予高劑量龍眼花水萃物14週後更提升了IRS-1和GLUT 4的表現量，此結果顯示龍眼花水萃物可藉由增加胰島素訊息傳遞相關蛋白質之表現量，使胰島素敏感性增加。 本研究結果顯示，龍眼花水萃物具有很好的抗氧化活性，且可改善高血壓、高胰島素血症、胰島素阻抗和降低體內氧化壓力。; Metabolic syndrome is a cluster of disorders, including hyperinsulinemia, insulin resistance, hypertriglyceridemia and hypertension that increase one's risk for type 2 diabetes and cardiovascular disease . Natural antioxidants were reported to ameliorate metabolic syndrome. Previous study in our laboratory has shown that Longan (Dimocarpus longan Lour.) flower had strong antioxidant activity in vitro. Therefore, the objective of this study was to evaluate the effect of the supplemention of Longan flower extract on metabolic syndrome. The first stage of this study was to analyze the antioxidative activity of Longan flower in vitro, the crude extracts were prepared by extracting Longan flower with boiling water and two solvents (95% ethanol, methanol) at room temperature. Then, the three different solvent extracts of Longan flower were tested for two different antioxidant assays, including DPPH free radical scavenging effect and the inhibition of Cu2+-induced oxidation of human LDL. The results of antioxidant assays revealed that the best effect was exhibited by the water extract, followed by ethanol and methanol. The EC50 value of water extract in scavenging DPPH radicals was 3.75±0.61 µg/mL, and its effect on delaying LDL oxidation is 1.57 times better than trolox at the same concentration level (1 µg/mL). The second stage of the study was to observe the glucose tolerance of rats after the acute treatment with Longan flower crude extract (125 mg/kg or 250 mg/kg) and glucose. Results of oral glucose tolerance test (OGTT) in rats showed that the plasma glucose levels of the Sprague-Dawley rats administered 250 mg/kg BW of Longan flower water extract (LFWE) were lower than the control group after 30 minutes of ingestion but insulin concentrations showed no difference with the control group at each time intervals . However, both the plasma glucose and insulin levels of the rats ingested Longan flower ethanol extract showed no significant difference with control group. These findings suggest that Longan flower water extract may delay or interference with the sugar absorption in the gastrointestinal tract without changing insulin secretion and its action. The third stage is to investigate the effect of long-term treatment of LFWE on rats with metabolic syndrome induced by high fructose diet. Male Sprague-Dawley rats of body weight around 250 g were randomly divided into four groups: group C, fed with standard Purina chow; group F, fed with high fructose diet alone; group L, fed with high fructose diet plus LFWE 125 mg/kg BW per day by gavage (a low dose group) and group H, fed high fructose diet plus LFWE 250 mg/kg BW per day by gavage (a high dose group). The dietary manipulation lasted for 14 weeks. Results of our study showed that, high fructose feeding for 2 weeks cause significant increase in sytosolic blood pressure, fasting plasma triglyceride and insulin levels without elevating fasting plasma glucose. And insulin resistance was demonstrated after the 4th week by OGTT. These results indicated that fructose-rich diet could cause a cluster of disorders in metabolic syndrome. In antioxidative capacity analyses, at the end of the 12-week experiment high fructose diet increased plasma TBARS and significantly decreased liver antioxidant enzyme activity . The supplementation of LFWE ameliorated insulin resistance by enhancing the expression of insulin signaling pathway related proteins, including GLUT 4 and insulin receptor substrate-1. LFWE supplementation was also found to decrease SBP and ameliorated oxidative stress. These findings indicate that Longan flower water extract may improve the symptoms of the metabolic syndrome in fructose-fed rats. 2007-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/99516 標題: 龍眼花水萃物對於腦部與腸道菌相抗憂鬱作用機轉之探討; Investigation of the anti-depression mechanisms of Longan flower water extract in the brain and gut microbiota 作者: 彭晉璋; Chin-Chang Peng 摘要: 憂鬱症是目前全球最常見的精神疾病，也是導致失能的主要原因。根據世界衛生組織 (WHO) 統計，目前約有2.8億人患有憂鬱症，其中，臺灣憂鬱症盛行率甚至為全球2倍之多，對於憂鬱症的預防更是當務之急。憂鬱症有多種可能病理機制，如：單胺理論、下視丘-腦下垂體-腎上腺軸 (HPA axis) 以及腸腦軸線 (gut-brain axis)，並且會導致多種症狀，包括：情緒低落、失去對事物的興趣、負面想法等。目前，憂鬱症主要治療方法是使用抗憂鬱藥物，但這些藥物伴隨不少副作用，因此，近年來具有抗憂鬱作用的天然產物成為新興輔助治療方式。龍眼是臺灣種植面積第五大的經濟作物，是重要的農作物之一，而農業試驗所在2019年時發現龍眼的花朵中含有具抗憂鬱潛力的天然分子。先前研究表明，龍眼花水萃物不僅可以提高類帕金森氏症疾病大鼠大腦紋狀體中的多巴胺含量，還有神經保護和抗氧化作用；另一研究表明，龍眼花水萃物可以顯著提高血清素和褪黑激素濃度及相關基因表現，從而緩解失眠症狀。然而，目前尚無已發表的文獻探討龍眼花水萃取物與憂鬱症之間的關係。因此，本研究旨在探討龍眼花萃取物在不可預期慢性溫和壓力 (unpredictable chronic mild stress, UCMS) 誘導大鼠產生憂鬱症狀的動物模型中的抗憂鬱作用及其機制。實驗結果發現，龍眼花水萃物可以降低血清中壓力因子皮質酮、前額葉皮質促發炎細胞因子濃度和單胺類神經傳導物質之轉換率來改善大鼠的憂鬱行為。此外，龍眼花水萃物也能影響大鼠的腸道菌相的組成，並形成特定優勢菌種如鼠乳酸桿菌 (Ligilactobacillus murinus)，這些菌種可能發揮抗憂鬱的輔助作用。總結來說，龍眼花水萃物可改善UCMS大鼠的憂鬱症狀，並可能是透過多種機制達到抗憂鬱效果。本研究成果為利用天然物治療及預防憂鬱症提供另一想法，並期待不同作用機制或臨床應用之探討，作為保健產品開發之科學參考依據。; Depression is currently the most prevalent mental illness and a major cause of disability worldwide. According to the World Health Organization (WHO), it is estimated that 280 million people suffered from depression in 2023. In Taiwan, the prevalence rate is 8.9%, which is nearly twice the global average. These figures highlight the critical importance of strategies for preventing depression. Various factors contribute to the progression and pathology of depression, such as the monoamine theory, the hypothalamic-pituitary-adrenal axis, and the gut-brain axis, leading to several symptoms, including depressed mood, diminished interest, and negative thinking, and so on. The primary treatment for depression is antidepressants; however, the medications may have side effects. Therefore, alternative approaches, especially natural products with anti-depression effects, are crucial in alleviating depression. Longan is one of the important economic crops in Taiwan. Its flower was recently observed to contain natural molecules with antidepressant potential by the Taiwan Agricultural Research Institute. A previous study demonstrated that Longan flower water extract (LFWE) could not only raise dopamine content in the striatum but also had neuroprotection and antioxidation effects in rats with Parkinson's-like disease, which shares some common pathological mechanisms with depression. Another study showed that LFWE could significantly raise serotonin and melatonin levels to relieve insomnia. Nevertheless, no published papers have examined the relationship between LFWE and depression. Consequently, our study aims to investigate the anti-depression effects and mechanisms of Longan flower water extract in the unpredictable chronic mild stress (UCMS)-induced rat depression model. In the experimental results, we found that LFWE could improve depression-like behaviors through lowering corticosterone, pro-inflammatory cytokines, and the turnover rate of monoamines. Furthermore, LFWE could affect the composition of gut microbiota and lead to specific dominant species, such as Ligilactobacillus murinus, considered to play a role in anti-depression. In conclusion, LFWE might have an anti-depression effect via multiple mechanisms. The outcome of the research could pave the way for using natural products in treating and preventing depression. Further investigations into the underlying mechanisms and clinical trials are warranted to support the development of functional foods. 2025-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/43453 標題: 龍眼花水萃物之乙酸乙酯區分層對高果糖誘發大鼠代謝症候群之改善功效; Ethyl Acetate Fraction of Longan (Dimocarpus longan Lour.) Flower Water Extract Attenuates Metabolic Syndrome in Fructose-Fed Rats 作者: Chieh-Yu Huang; 黃潔妤 摘要: 代謝症候群因與許多重大之慢性疾病(如:糖尿病及心血管疾病等) 間有密切相關性，為近年來日益受到重視之健康議題，其危險因子包含腹部肥胖、高血糖、血脂異常及高血壓等。本研究室於先前之研究已發現龍眼 (Dimocarpus longan Lour.) 花在體外試驗中具有很好的抗氧化活性，且在高果糖動物模式中證實龍眼花水萃物具有改善代謝症候群諸多症狀之功效。因此本研究之目的為評估龍眼花不同極性區分層對高果糖誘發代謝症候群之改善功效，以便日後尋找龍眼花中之有效成分。 本研究分為兩階段進行，第一階段為急性灌食試驗，用以觀察龍眼花水萃物及其區分層對大鼠葡萄糖耐受能力之影響。在此部分之試驗中，使用正常之Sprague-Dawley雄性大鼠，隨機分成五組，分別灌食龍眼花水萃物、乙酸乙酯區分層、正丁醇區分層、水區分層及去離子水後，進行口服葡萄糖耐受性試驗，觀察各組血糖變化情形。其結果顯示，乙酸乙酯區分層及水區分層皆具改善葡萄糖耐受能力的作用，因此同時選擇此二樣品進入第二階段之試驗。 第二階段則為長效期試驗，採高果糖飲食誘發大鼠代謝症候群之動物模式進行，用以觀察龍眼花水萃物及其區分層改善代謝症候群之功效。此部分試驗同樣選用Sprague-Dawley大鼠，並隨機分為五組：基礎值組 (B) 每日灌食去離子水並給予標準飼料；控制組 (C) 每日灌食去離子水並給予高果糖飼料；龍眼花水萃物組 (LFWE) 每日灌食龍眼花水萃物250 mg/ml/kgBW並給予高果糖飼料；龍眼花水萃物之乙酸乙酯區分層組 (EA) 每日灌食乙酸乙酯區分層36.3 mg/ml/kg BW並給予高果糖飼料；以及龍眼花水萃物之水區分層組 (W) 每日灌食水區分層147.5 mg/ml/kg BW並給予高果糖飼料。實驗期共16週。結果顯示，C組大鼠之禁食血漿葡萄糖、胰島素、三酸甘油酯、膽固醇濃度與血壓皆顯著上升，顯示長期餵飼高果糖飼料已顯著誘發出代謝症候群之症狀。 龍眼花水萃物於本實驗中，具有顯著改善腹部脂肪堆積、禁食血漿葡萄糖、胰島素、三酸甘油酯、總膽固醇濃度上升及高血壓等功效，有顯著改善胰島素阻抗之現象。而其效果可能來自於減少大鼠體內氧化壓力及提高IR、IRS-1、Akt、GLUT4等蛋白質之表現量。 在龍眼花水萃物之乙酸乙酯區分層部分，發現其與龍眼花水萃物具有許多相似之功效：顯著改善腹部脂肪堆積、禁食血漿葡萄糖、胰島素、三酸甘油酯濃度、高血壓及胰島素阻抗之現象。而在體內抗氧化壓力方面，也同樣具有改善血漿TBARS濃度，及增加肝臟抗氧化酵素Glutathione reductase之活性等功效，並且在胰島素訊息傳遞相關蛋白之表現量亦有上升的情形。 在龍眼花水萃物之水區分層部分，則具有顯著降低禁食血漿葡萄糖、總膽固醇濃度的作用，並同樣具有減少腹部脂肪堆積、降低肝中三酸甘油酯濃度等功效；但對胰島素阻抗與高三酸甘油酯血症並無顯著改善的功效。 綜合以上結果，乙酸乙酯區分層在改善代謝症候群之諸多症狀上皆類似於龍眼花水萃物，因此推測龍眼花水萃物中改善代謝症候群之有效成分應存在於乙酸乙酯區分層當中。; Metabolic syndrome becomes an important issue recently. It has strong correlation with several chronic disease, for instance, diabetes and cardiovascular disease. The risk factors of metabolic syndrome contain abdominal obesity, hyperglycemia, dyslipidemia and hypertension. Previous study in our laboratory has shown that Longan (Dimocarpus Longan Lour.) flower had strong antioxidant activity in vitro. Furthermore, we also have demonstrated that Longan flower water extract (LFWE) can improve the symptoms of the metabolic syndrome in animal model. Therefore, the purpose of this study was to investigate the effect of each fraction of Longan flower water extract on metabolic syndrome. We expect to find effective compound in Longan flower in the future. The study was carried out into two parts. The first part was an acute study to examine the effects of LFWE and its fractions on glucose tolerance in rats. Male Sprague-Dawley rats were randomly divided into five groups, administered LFWE, ethyl acetate fraction, n-butanol fraction, water fraction and ddH2O by gavage respectly. Results of oral glucose tolerance test (OGTT) in rats showed that both EA and W fraction can improve glucose tolerance. Therefore, we choose these two fractions to do the following study. The following study was to investigate the effect of long-term treatment of EA and W fraction on rats with metabolic syndrome induced by high fructose diet. Male Sprague-Dawley rats were randomly divided into five groups: group B, fed with standard Purina chow; group C, fed with high fructose diet ; group LFWE, fed with high fructose diet plus LFWE 250 mg/ml/kg BW per day by gavage ; group EA, fed with high fructose diet plus EA 36.3 mg/ml/kg BW per day by gavage ; group W, fed with high fructose diet plus W 147.5 mg/ml/kg BW per day by gavage. The dietary manipulation lasted for 16 weeks. Results of this study showed that, high fructose feeding cause significant increase in abdominal fat mass, fasting plasma glucose, insulin, triglyceride, cholesterol levels and systolic blood pressure. These results indicated that fructose-rich diet could cause a cluster of disorders in metabolic syndrome. Treatment with LFWE significantly improved abdominal fat accumulation, hypertriglyceridemia, hyperinsulinemia, hyperglycemia, hypercholesterolemia, hypertension and insulin resistance. To further evaluated the possible mechanism of LFWE, we found that the rats showed decreased oxidative stress and increased expression of insulin signaling pathway related protein, including insulin receptor (IR), insulin receptor substrate-1 (IRS-1), Akt and glucose transporter Ⅳ(GLUT4). The supplement of EA fraction showed many similar efficacies as LFWE on abdominal fat, fasting glucose, insulin, triacylglyceride, hypertension and insulin resistance. EA fraction also showed the ability to decrease plasma TBARS and enhance glutathione reductase activity in fructose-fed rats. And the expressions of insulin signaling pathway related protein were also enhanced. W fraction significantly decreased fasting glucose, total cholesterol, abdominal fat and liver triacylglycerol accumulation. But it shown no effects on insulin resistance and hypertriglyceridemia induced by high fructose diet instead. According to these finding, we suggested the effective components for ameliorating metabolic syndrome should be in the ethyl acetate fraction. 2009-01-01T00:00:00Z