【作者】 徐辉；

【导师】 张卫明； 张玖；

【作者基本信息】 南京农业大学 ， 食品科学， 2008， 硕士

【摘要】 香水莲花（Nymphaea hybrid）是睡莲科睡莲属热带大型睡莲,其化学成分和生物活性国内外迄今未见研究报道。香水莲花除了含有碳水化合物、脂肪、蛋白质等成分之外,还富含多糖、黄酮、生物碱等活性成分。本文对香水莲花中的水溶性成分和醇溶性成分分别进行了提取分离和初步的化学结构测定,并初步研究了其降血脂和美白的活性。首先,用水提醇沉法从香水莲花中获得粗多糖XLDT,采用十六烷基三甲基溴化铵（CTAB）络合法从XLDT中分离出酸性多糖ADT和中性多糖NDT,其中酸性多糖为XLDT的主要部分,约占89%。利用葡聚糖凝胶Sephadex G-150对酸性多糖ADT进行柱层析分离,得到ADT-Ⅰ和ADT-Ⅱ两个组分,其中以ADT-Ⅱ为主要。采用高效液相法得到ADT-Ⅱ的分子量约为2.758×10⁵道尔顿。完全酸水解后的核磁共振谱和高效液相色谱分析显示,ADT-Ⅱ的单糖组成系以甲酯化了的半乳糖醛酸为主,同时还含有少量的半乳糖和甘露糖。其次,采用80%的乙醇对香水莲花进行回流提取,得到的粗提物以硅胶柱色谱法进行分离纯化,共得到5个化合物。通过核磁共振(包括¹H-NMR,¹³C-NMR)、质谱等手段鉴定出其中两个化合物分别为硬脂酸和β-谷甾醇,其余成分的鉴定工作仍在进行中。第三,本文首次采用水蒸气蒸馏法分别从红色、紫罗兰色两种不同颜色的香水莲花全花中提取挥发油,用气相色谱-质谱对挥发油的化学成分进行了分析。从两个样品挥发油中共鉴定出37种化学成分。研究结果表明,来自两种不同颜色的香水莲花挥发油,其主要成分相同,分别为苄醇、6,9-十七碳二烯、8-十七碳烯、2-十七酮、正十五烷等,但含量有别。其次要组分存在一定差异。最后,本文对香水莲花又分别进行了降血脂和美白活性功能研究。高血脂动物模型试验结果表明,香水莲花具有较强的降血脂功能和良好的抗脂肪肝作用。美白试验以L-酪氨酸为底物,以常用美白剂熊果苷为阳性对照,用马铃薯制备酪氨酸粗酶液,分别以香水莲花雄蕊和花托的乙醇提取物为试验样品。研究结果表明,香水莲花雄蕊和花托的乙醇提取物对酪氨酸酶均具有有良好的抑制作用,且相同浓度的雄蕊乙醇提取物对酪氨酸酶活性的抑制率高于花托乙醇提取物,两者对酪氨酸酶活性的抑制率均不亚于阳性对照。鉴于香水莲花乙醇提取物对酪氨酸酶具有良好的抑制作用,可以考虑将其作为化妆品行业中新的美白剂。更多还原

【Abstract】 Nymphaea hybrid is one of large tropical lotus of Nelumbl Nuciferea Gacrtn.There is no correlative report on it’s chemical composition and biological activity all over the world so far.Besides carbohydrate,fat and protein,Nymphaea hybrid also contains polysaccharide,flavonoid and alkaloid that may have obvious biological activity and physiological functions.In this thesis,the extraction,isolation,purifica- tion as well as structure determination of hydro-soluble and alcoh-soluble constituents from Nymphaea hybrid were studied,and its effects on the lipids level in blood and on the process of melanin production were also researched preliminarily in vivo or in vitro respectively.Firstly,the crude polysaccharide named XLDT was extracted with hot water and precipitated with ethanol,then the acidic polysaccharide（ADT） and neutral polysaccharide （NDT）in XLDT were divided each other by CTAB complexation,and ADT took the percentage of about 89%.After passing through the column of Sephadex G-150 ATD was further separated into ADT-Ⅰand ADT-Ⅱ,and ADT-Ⅱis the main part.The molecular weight of ADT-Ⅱwas determined to be about 2.7^*10⁵ Dalton by high performance liquid chromatography（HPLC） technology.After complete hydrolysis in acid,the hydrolysate of ADT-Ⅱwas analyzed by nuclear magnetic resonance（NMR） spectrum and gas chromatographic（GC）.The result showed that ADT-Ⅱwas mainly made up of galacturonic acid,and with galactose and mannose as the minor parts.Secondly,the raw material of Nymphaea hybrid was extracted by 80%ethanol.Five compounds were isolated from the ethanol extract through the silica gel and Sephadex LH-20 column chromatography.Two compounds were identified as stearic acid andβ-sitosterin by the spectroscopic methods(¹H NMR,¹³C NMR and MS).The identification of other compounds is in progress.Thirdly,two defferent color flowers（red,violet） from Nymphaea hybrid were used as materials,the essential oil was extracted respectively by distillation and its chemical constituents were analyzed by GC-MS.37 compounds were separated and identified.The main constituents of essential oil from the two colour samples were very similar as follows,Benzyl Alcohol,6,9-Heptadecadiene,8-Heptadecene,2-Heptadecanone, pentadcane,etc.At last,the biological activites of the flower of Nymphaea hybrid such as decreasing the level of blood lipids and inhibition the process of melanin production were studied. Quails fed with high lipid food to form hyperlipidemic models were taken as the experiment animals.The result indicated that the flower powder of Nymphaea hybrid could decrease the level of blood lipids and protect the liver against fatty accumulation.In the inhibiting melanin experiment,the tyrosinase inhibition activity of the stamen and receptacle ethanol extracts were tested in vitro comparing with the common used skin whitening agentβ-Arbutin（+CK）,using the crude enzyme liquid of tyrosine（Tyr） which was extracted from potato.The results showed that,both of the ethanol extracts of stamen and receptacle could inhibit the activity of tyrosinase,The extract of stamen showed a higher inhibitory rate followed by the extract of receptacle,and then theβ-Arbutin.In view of the good inhibition activity on tyrosinase,the ethanol extracts of the flower of Nymphaea hybrid could be used in the area of cosmetic industry as a new whitening agent.更多还原