Miel des fleurs

上次跟蛙去土城踏青遇到可愛的歐姬桑和歐媽桑
老伯說龍眼花可以清血脂
一時好奇之下就買了一大包回家喝
一茶包可以沖個2000ml...最好是沖到沒有顏色
我發現有清腸胃的功能
大腹婆都變成小腹婆了 呵呵呵

馬上call out回家問
但竹崎沒有農家在量產，好可惜哦～

以下就是龍眼花功能的Reference------------------------------------------------------------

題名: 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: 沈宜蓁
Shen, Yi-Jane
貢獻者: 孫璐西
臺灣大學：食品科技研究所
關鍵詞: 龍眼花
抗氧化
Longan flower
antioxidant
日期: 2005
上傳時間: 2007-11-27T03:23:36Z
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.

題名: 龍眼花抗氧化成分之研究
Studies on the Antioxidative Components of
Longan (Dimocarpus longan Lour.) Flower
作者: 謝孟潔
Hsieh, Meng-Chieh
貢獻者: 孫璐西
臺灣大學：食品科技研究所
關鍵詞: 抗氧化
龍眼花
epicatechin
proanthocyanidin A2
antioxidant
Longan flower
epicatechin
proanthocyanidin A2
日期: 2006
上傳時間: 2007-11-27T03:28:25Z
摘要: 動脈粥狀硬化為造成心血管疾病之主要原因，而低密度脂蛋白（low density lipoprotein, LDL）膽固醇的氧化為啟動動脈粥狀硬化的重要步驟；抗氧化劑可以增加LDL對氧化傷害的抵抗力，因此攝取含有抗氧化成分之食品應有助於預防動脈粥狀硬化之發生。本研究室於前一年度研究顯示，龍眼（Dimocarpus longan Lour.）花具有良好之抗氧化效果，因此本研究以抗氧化活性為導向進行龍眼花活性成分之分離純化，並以「抑制銅離子誘導人類LDL之氧化」為主要抗氧化活性之檢測方法，進而鑑定出有效之抗氧化成分。
龍眼花甲醇萃取物以正己烷、乙酸乙酯、正丁醇及水四種溶劑進行分配萃取，其中以乙酸乙酯區分層之抗氧化效果最佳，其對於清除DPPH自由基之EC50為5.28 ± 1.14 μg/mL。在延緩LDL氧化方面，其效果為同濃度（1 μg/mL）下Trolox之1.14倍，並且具有最高之總酚（701.7 ± 29.3 mg gallic acid /g dry weight of sample）與總類黃酮（213.7 ± 14.8 mg catechin equivalent /g dry weight of sample）含量。
進一步將乙酸乙酯區分層以矽膠管柱層析法予以分離純化，得到20個次區分。由DPPH自由基清除能力試驗可知，中至高極性之次區分（F9~19）具有較好之抗氧化效果。ORAC試驗結果顯示F8~11之抗氧化效果十分優異，其中以F9（以ethyl acetate/n-hexane=60/40, v/v沖提）最佳，ORAC值為25.07 ± 4.08 Trolox equivalent。抑制銅離子誘導人類LDL氧化試驗結果亦顯示，F8~11可有效延緩LDL之氧化，其中以F10（以ethyl acetate/n-hexane=70/30, v/v沖提）之效果特別突出，為同濃度（1 μg/mL）下Trolox之1.72倍。分析各次區分之抗氧化物質含量，發現F9之總酚（970.4 ± 11.2 mg gallic acid /g dry weight of sample）與總類黃酮（732.9 ± 19.0 mg catechin /g dry weight of sample ）含量皆為最高；且F8~11之總類黃酮含量趨勢與抗氧化效果之趨勢相符，並皆顯著高於區分前之乙酸乙酯區分層。因此推測龍眼花之抗氧化性可能與酚類中類黃酮物質含量或組成具有高度相關性。
HPLC分析F9發現其僅含一個成分，該化合物以 IR、MS、UV-Vis與1H-NMR、13C-NMR、2D-NMR等光譜分析，鑑定出F9中主要抗氧化活性成分為(-)-epicatechin。以Sephadex LH-20分離F10中成分後，則鑑定出其中兩個主要抗氧化活性成分為(-)-epicatechin與proanthocyanidin A2，兩者皆具抑制LDL氧化效果，分別為同濃度（0.5 μg/mL）下Trolox之1.95與2.04倍。每克龍眼花中(-)-epicatechin與proanthocyanidin A2之含量經HPLC分析，各約為5.58 mg及1.70 mg。本實驗結果顯示龍眼花中具有優異抗氧化效果之成分，有潛力發展為具有保健功效之食材。
Atherosclerosis is the major cause of cardiovascular disease, and the oxidation of low density lipoprotein (LDL) cholesterol is the important step to initiate atherosclerosis. Antioxidants can increase the resistance against oxidative damage, so the supplementation of food with antioxidants may help prevent the incidence of atherosclerosis. Previous year study in our laboratory has shown that Longan (Dimocarpus longan Lour.) flower had good antioxidative activity. Therefore, the objective of this study is to conduct antioxidant activity-guided separation and purification of Longan flower by the major antioxidative assay, the inhibition of Cu2+-induced human LDL oxidation, and to identify the effective compounds.
After liquid-liquid partition of Longan flower methanol extract with n-hexane, ethyl acetate, n-butanol and water, the ethyl acetate fraction showed the best antioxidant activity. The EC50 value of the ethyl acetate fraction in scavenging DPPH radicals was 5.28 ± 1.14 μg/mL, and its effect of delaying LDL oxidation is 1.14 times better than Trolox at the same concentration level (1μg/mL). Besides, the ethyl acetate fraction had the highest contents of total polyphenol (701.7 ± 29.3 mg gallic acid /g dry weight of sample) and flavonoid (213.7 ± 14.8 mg catechin equivalent /g dry weight of sample).
Silica gel chromatography was employed to fractionate the ethyl acetate fraction of Longan flower methanol extract, and twenty sub-fractions were obtained. DPPH assay showed that the sub-fractions with medium to high polarity had better antioxidative activities. Result of ORAC assay revealed that F8~11 were the more effective sub-fractions and F9 (eluted by ethyl acetate/n-hexane=60/40, v/v) gave the highest ORAC value (25.07 ± 4.08 Trolox equivalent). As for the effect of Cu2+-induced oxidation of human LDL, F8~11 also showed better effect in delaying LDL oxidation. Among them, F10 (eluted by ethyl acetate/n-hexane=70/30, v/v), which had superior effect, was 1.72 times better than Trolox at the same concentration level (1μg/mL). Further analysis of these sub-fractions showed that F9 contained the hightest amounts of total polyphenol (970.4 ± 11.2 mg gallic acid /g dry weight of sample) and total flavonoid (732.9 ± 19.0 mg catechin /g dry weight of sample). The trends of total flavonoid contents and the antioxidative activities of the four sub-fractions (F8~11) were similar, we therefore supposed that the antioxidative activity of Longan flower was highly related to its total flavonoid content or composition.
There was only one major compound present in F9 by HPLC analysis and it was identified as (-)-epicatechin by spectrometric analysis of IR, MS, UV-Vis, 1H-NMR, 13C-NMR and 2D-NMR. After separating F10 by Sephadex LH-20, two major components were identified as (-)-epicatechin and proanthocyanidin A2. Both of them had superior effect in delaying LDL oxidation, and the lag time of each compound was 1.95 ( (-)-epicatechin ) and 2.04 ( proanthocyanidin A2 ) times better than Trolox at the same concentration level (0.5μg/mL). The contents of (-)-epicatechin and proanthocyanidin A2 in Longan flower were quantified by HPLC to be 5.58 and 1.70 mg/g dry weight, respectively. This study showed that Longan flower contained components with excellent activity, it thus has good potential to be developed as a functional food.