【作者】 李君珂；

【导师】 姜子涛；

【作者基本信息】 天津商业大学 ， 食品科学， 2012， 硕士

【摘要】 蓼科植物何首乌（Polygonum multiflorum Thunb.）为多年生缠绕性草本，通常根据何首乌的部位不同，块根称为“何首乌”，藤茎称为“夜交藤”，叶称为“首乌叶”。已从何首乌、夜交藤中得到多种黄酮类化合物[1-4]，而首乌叶的研究应用相对较少[5,6]。黄酮类化合物作为优良的自由基清除剂和抗氧化剂，已广泛应用于食品和营养保健品中[7]。本课题的研究包括四个部分：（1）利用微波辅助提取法提取了首乌叶黄酮，对影响首乌叶总黄酮提取的因素进行探讨。实验结果表明，最佳条件是：乙醇浓度70%，功率400W，时间5min，温度70℃，料液比（w/v）为1:20，在此条件下得到首乌叶总黄酮的提取率为3.86%。（2）以吸附量和解析率为参考指标，比较了AB-8、D4006、S-8、D101、NKA-Ⅱ、NKA-9六种大孔树脂对首乌叶总黄酮的吸附和解析效果，并通过HPLC分析证明大孔树脂对首乌叶黄酮起到分离纯化的效果。结果表明：D101大孔树脂对首乌叶总黄酮具有较好的吸附和解析性能，吸附容量为29.0mg·g⁽-10，解析率达到98.8%，选择浓度为1.0mg·g-1的样液上样，用pH值为6.0、浓度为70%的乙醇溶液洗脱。该方法简单易行，分离效果好，适于首乌叶总黄酮的分离纯化。（3）建立高效液相色谱—质谱法（HPLC-LC/MS）分析首乌叶中活性成分,其中有七种黄酮类成分：木樨草苷、牡荆素、芹菜素-7-葡萄糖苷、金丝桃苷、芦丁、紫云英苷和槲皮苷。所建立的高效液相色谱—质谱法高效有效，可以用于快速鉴定首乌叶中黄酮类成分，并首次在该植物中鉴定出芹菜素-7-葡萄糖苷和紫云英苷。（4）测定首乌叶黄酮溶液的总体抗氧化能力、清除超氧阴离子自由基能力、清除羟基自由基能力、清除DPPH自由基能力和对卵黄脂蛋白脂质抗氧化能力，并与合成抗氧化剂Vc、PG比较，对首乌叶黄酮溶液抗氧化和清除游离基活性进行评价。结果表明：首乌叶黄酮溶液具有良好的抗氧化效果，在一定浓度范围内，首乌叶黄酮溶液对卵黄脂蛋白脂质抗氧化能力优于Vc和PG，其总体抗氧化能力、清除超氧阴离子自由基能力优于PG略低于Vc，清除羟自由基能力优于Vc低于PG，但清除DPPH自由基能力比Vc和PG略弱。更多还原

【Abstract】 Polygonum multiflorum Thunb., which is a traditional Chinese medicinal plant wasofficially listed in the Chinese Pharmacopoeia（China Pharmacopoeia Committee,2010）, is one ofthe most important and commonly used traditional Chinese medicine （TCM）. It’s dried roots andstems are well known as “He shou wu” and “Shou wu teng” and it’s leaves are called “Shou wuye” respectively. P. multiflorum has been used in many remedies of traditional medicine inChina such as “Shouwu Yanshou Pian” and other countries for its possessing many activitiessuch as antioxidation, anti-aging, reducing blood lipid and improve memory.The leaves of Polygonum multiflorum Thunb flavonoids were extracted bymicrowave-assisted extraction technique. The effects of ethanol concentration, microwave power,microwave treatment time, microwave treatment temperature and ratio of material to solvent onthe extraction yields were investigated. The experimental results showed that the optimumconditions of microwave extraction were as follows: ethanol concentration70%, microwavepower400W, microwave treatment time5min, microwave treatment temperature70oC and theratio of material to solvent1:20（w/v）. Under the above–mentioned conditions, the extract rate oftotal flavonoids was3.86%.Adsorption and desorption properties of six kinds of resins, including AB-8, D4006, S-8,D101, NKA-II and NKA-9, for the leaves of P. multiflorum flavonoids were studied in this paperusing total flavonoids content. Furthermore, with the method of HPLC, we proved that themacroporous resins had a separation and purification effect on flavonoids from the leaves of P.multiflorum. It was showed that the macroporous resins D101was selected with high desorptioncapacity (28.99mg·g^-1) and desorption rate （98.84%）. The concentration of the sample solutionwas1.0mg·mL-1, and pH6.0,70%of ethanol could accomplish desorption completely. Thismethod is simple and feasible and fit for separation and purification of flavonoids from theleaves of P. multiflorum.Leaves of P. multiflorum were analysed with a high performance liquidchromatography-liquid chromatography/mass spectrometry （HPLC-LC/MS） system equipped inpositive mode. In this study, an HPLC-LC/MS was successfully developed to identify andcharacterize seven flavonoids （Luteoloside, Vitexin, Apigenin-7-glucoside, Hyperoside, Rutin, Astragalin, Quercitrin）, one stilbene glycoside（2,3,5,4’-tetrahydroxystilbane-2-O-β-D-glucoside）and one sterol （Stigmasterol） of the leavesof P. multiflorum. Among these compounds, Apigenin-7-glucoside and Astragalin are isolatedfrom leaves of P. multiflorum for the first time. The proposed method is rapid and reproducibleand is useful for characterization and evaluation of leaves of P. multiflorum flavonoids andstilbene glycoside.In the present research, the total antioxidant activities,superoxide anion,hydroxyl radicalscavenging activities, scavenging DPPH radical of nutmeg and antioxidant activities onlipoprotein and lipid of yolk （Myristica fragrans Houtt）flavonoids from leaves of P. multiflorumwere determined and the results were compared with those of synthetic antioxidants such asascorbic acid（Vc）and propyl gallate（PG）.The results revealed clearly demonstrated thatflavonoids from leaves of P. multiflorum possesses marked antioxidant activities on on lipoproteinand lipid of yolk was concentration dependent and was higher than those of Vc and PG.Totalantioxidant activities and superoxide anion, hydroxyl radical scavenging activities of flavonoidsfrom leaves of P. multiflorum were higher than PG and weaker than Vc. Hydroxyl radicalscavenging was higher than Vc and weaker than PG. DPPH radical scavenging activities was alittle weaker than those of two synthetic antioxidants.更多还原