银杏达莫注射液的制备及含量测定

目的:探讨银杏达莫注射液的制备方法及用高效液相色谱法(HPLC法)测定其主要成分的含量.方法:测定双嘧达莫的含量采用shimack-VPODS色谱柱,以磷酸溶液(1→3)调节pH值至4.6的0.1%磷酸二氢钠-甲醇(20:75)为流动相,检测波长为290 nm;测定银杏总黄酮的含量采用KromasiL-C18色谱柱,以磷酸溶液-甲醇(50:50)为流动相,检测波长为360 nm.结果:线性范围双嘧达莫为6.12～24.48μg/mL,银杏总黄酮为0.047 6～0.190 4μg/mL.双嘧达莫的平均回收率为99.82%,RSD为0.85%;银杏总黄酮的平均回收率为99.53%,RSD为0.69%.结论:HPLC法灵敏、准确、重现性好,可用于测定复方银杏达莫注射液.     

复方红花滴丸的质量标准初步研究

目的:建立实验室制备的复方红花滴丸中银杏总黄酮的测定方法。方法:单波长扫描在最大吸收波长入max=370nm处,以芦丁对照品为对照,对实验室制备的复方红花滴丸中银杏总黄酮的含量进行测定。结果:实验室制备的复方红花滴丸中的银杏总黄酮在4～10μg线性关系良好,r=0.9998,平均回收率99.8%,RSD=0.288%(n=5),五批实验室制备的复方红花滴丸中银杏总黄酮的含量分别为23.953%、22.063%、25.322%、26.086%、42.000%。结论:薄层扫描法测定实验室制备的复方红花滴丸中银杏总黄酮的含量方法简便、快捷可作为该制剂的银杏总黄酮的测定方法。     

分光光度法测定复方银杏口服液中总黄酮的含量

目的研究复方银杏口服液中总黄酮的含量测定方法。方法将复方银杏口服液样品用亚硝酸钠与硝酸铝显色后，采用分光光度法测定，测定波长为500 nm，对照品为芦丁。结果测得3批复方银杏口服液中总黄酮的平均含量为0.598 4 mg·mL^-1，加样回收率为101.6%，RSD＝0.91%。结论该方法简便、准确、灵敏度高，可作为复方银杏口服液中总黄酮的含量测定方法。     

大孔吸附树脂纯化银杏活性化合物的工艺研究

目的优选大孔吸附树脂分离纯化银杏总黄酮工艺,并讨论其对银杏内酯的影响,探索一条适合工业化生产的工艺.方法以总黄酮和内酯的吸附率和解吸率为指标,采用静态吸附和动态吸附对银杏总黄酮和内酯分离纯化工艺进行优化.结果 pH=5、流速为1.0 mL·min-1,树脂用量与吸附液之比为1:10,70%乙醇作为洗脱剂为理想条件.结论工艺合理,能有效分离纯化银杏总黄酮,黄酮含量达26%,内酯含量达6%.     

HPLC测定银杏总黄酮自乳化微乳中银杏总黄酮的含量

目的:建立高效液相色谱法测定银杏总黄酮自乳化微乳中银杏总黄酮的含量。方法:采用菲罗门-C₁₈（250 mm×4.6 mm,5μm）色谱柱,以甲醇-0.4%磷酸溶液（50∶50,v/v）为流动相,流速为1.0 ml·min^-1,检测波长为360 nm,柱温为30℃。结果:银杏总黄酮中槲皮素、山柰素和异鼠李素三种成分分离度较好,槲皮素在2.0⁴0.0μg·ml^-1质量浓度范围内,山柰素在3.0⁶0.0μg·ml^-1质量浓度范围内,异鼠李素在2.0⁴0.0μg·ml^-1质量浓度范围与峰面积呈良好的线性关系。槲皮素、山柰素和异鼠李素的平均回收率分别为98.4%,99.7%和100.5%,RSD分别为0.92%,0.62%和1.24%（n=9）。结论:该方法对银杏总黄酮自乳化微乳中三种成分分离效果较好,辅料无干扰,专属性强、稳定可靠,适用于银杏总黄酮自乳化微乳中银杏总黄酮的含量测定。     

银杏酸凝胶剂的研制

目的:研制银杏酸凝胶剂,并建立制剂的质量控制方法.方法:以银杏酸为主药、卡波普940为基质制备凝胶剂,采用高效液相色谱法测定制剂中银杏酸含量. 结果:所得制剂性质稳定,含量测定平均加样回收率为96.87%,RSD值为2.2%. 结论:该凝胶剂制备工艺简单、可行,质量控制方法准确可靠.     

天山雪莲二倍体与四倍体总黄酮含量的测定与比较

目的:测定与比较天山雪莲二倍体与四倍体组培苗总黄酮含量.为四倍体天山雪莲进一步开发利用奠定基础.方法:用紫外分光光度法测定天山雪莲二倍体与四倍体总黄酮的含量.结果:天山雪莲组培苗中,四倍体总黄酮含量大于二倍体总黄酮含量,且相对于二倍体总黄酮含量增加23%.结论:四倍体天山雪莲在总黄酮含量上增高,具有开发利用价值.     

HPLC测定银杏叶片中总黄酮醇苷和萜类内酯的含量

目的 测定银杏叶片中总黄酮醇苷和银杏萜类内酯的含量.方法 采用HPLC法,色谱柱为YMC-Pack ODS-A(150mm×6.0 mm含量,5 μm);流动相分别为甲醇-0.4%磷酸溶液(55:45)、水-甲醇-四氢呋喃(75:25:12);流速1.0 ml·min-1;检测波长360 nm;进样量10 μl.结果 槲皮素、山柰素和异鼠李素等3种黄酮苷元、白果内酯及银杏内酯A、B、C等4种银杏萜类内酯均能得到良好分离,标准曲线线性关系良好.结论 所建方法准确、灵敏、稳定、可靠,可满足定量分析的需要.     

枸杞子不同提取物中总黄酮含量的比较

目的:通过不同的测定方法比较枸杞子不同提取物总黄酮含量,以确定更科学的测定方法和为探索最佳的黄酮提取方法提供科学依据.方法:以枸杞总黄酮含量为指标,用水和乙醇为提取溶剂,回流提取和超声波提取法提取总黄酮,以铝盐比色法测定总黄酮的含量.结果:铝盐比色法测定总黄酮简便、灵敏和稳定.超声波提取法较回流提取法好,具有提取时间短、提取效率高、所需温度低等优点.结论:所有提取物中75%乙醇超声提取物中总黄酮的含量最高.     

银杏黄酮纯化工艺研究

目的:考查非水体系中ZX-4型配位吸附树脂对银杏总黄酮类成分的分离纯化方法.方法:根据银杏黄酮的结构特征,考查ZX-4型配位吸附树脂的吸附性能,并采用HPLC法对银杏总黄酮进行定量分析.结果:ZX-4型配位吸附树脂对银杏总黄酮类成分吸附选择性高.以5%HAc乙醇溶液作为洗脱剂,银杏黄酮纯度提高至53.2%,起到了纯化精制的目的.结论:以配位吸附树脂ZX-4作为纯化银杏黄酮的吸附剂;吸附容量大,解吸容易,分离纯化方法简便有效.     

银杏黄酮类物质抗肿瘤作用初探

目的探测银杏黄酮类物质的抗肿瘤作用。方法微核检测法测定银杏黄酮对致畸作用的防护;H3标记法检测银杏黄酮对体外培养的YAC-I细胞增殖的影响;原位注射法检测银杏黄酮对小鼠体内S-180实体瘤生长的影响。结果银杏黄酮处理组小鼠的微核率明显低于对照组,抑核率为48.23%;YAC-I细胞在银杏黄酮作用24h和48h后,增殖受到明显抑制,浓度为2500μg/ml时,增殖基本停滞;荷瘤小鼠在接受原位注射银杏黄酮后,肿瘤生长受到明显抑制,抑瘤率为56.99%。结论银杏黄酮可防护环磷酰胺的致畸作用;对体内体外肿瘤细胞的增殖均具抑制作用。     

银杏提取物活性成分的新剂型研究概述

银杏提取物的主要活性成分为银杏黄酮类化合物和银杏内酯类化合物,本文综述银杏提取物活性成分的种类和药理功效,并重点从缓控释制剂、增溶型固体制剂、纳米微粒制剂、定时定位给药制剂四个方面,对银杏提取物中银杏黄酮类和内酯类化合物的新剂型研究进展进行综述。     

Metabolism of quercetin and kaempferol by rat hepatocytes and the identification of flavonoid glycosides in human plasma

1. The metabolism of the flavonoids quercetin and kaempferol by rat hepatocytes was investigated using liquid chromatography coupled with electrospray mass spectrometry (LC-ESI MS). Quercetin and kaempferol were extensively metabolized (98.8 +/- 0.1% and 81.0 +/- 5.1% respectively, n = 4), with four glucuronides of quercetin and two of kaempferol being detected after incubation. 2. The glucuronides of quercetin and kaempferol formed upon incubation with rat hepatocytes were identified as the same ones formed after incubation with the UDP-glucuronosyltransferase isoform UGT1A9. 3. In addition, plasma samples from human volunteers taken after consumption of capsules of Ginkgo biloba, a plant rich in flavonoid glycosides, were analysed by LC-MS for the presence of flavonoid glucuronides and flavonoid glycosides. Reported is evidence for the presence of flavonoid glycosides in samples of plasma. 4. The results suggest that UGT1A9 is a key UDP-glucuronosyltransferase isoform for the metabolism of flavonoids, and that absorption of intact flavonoid glycosides is possible.     

银杏叶黄酮类化合物的分离纯化

目的研究银杏叶总黄酮的提取工艺。方法用正交实验确定银杏叶总黄酮的最佳浸提工艺;采用新型大孔吸附树脂对银杏叶总黄酮进行吸附及洗脱性能实验;同时采用高效液相色谱法进行分析检测。结果最佳浸提条件为温度90℃、溶剂比20∶1、提取4次、每次1 h;筛选出效果较好的D201型树脂,确定了最佳的工艺参数,高效液相色谱法检测显示总黄酮含量达71%以上。结论该法成本低,操作简单,树脂可重复利用,有较好的工业化前景。     

银杏叶胶囊联合认知训练治疗稳定期慢性阻塞性肺病患者认知功能障碍临床观察

目的：观察银杏叶胶囊联合认知训练对稳定期慢性阻塞性肺疾病（ chronic obstructive pulmonary disease,COPD）患者认知功能障碍的影响,并初步探讨其作用机制。方法60例稳定期COPD患者随机分为常规治疗组（ A组）,银杏叶胶囊治疗组（B组）,认知训练组（C组）和银杏叶胶囊联合认知训练组（D组）,各15例,观察3个月,各组患者治疗前后简易智能精神状态检查量表（ Mini?Mental State Exam,MMSE）和蒙特利尔认知评估量表（ Montreal cognitive assessment,MoCA）评分进行比较分析,并采用酶联免疫吸附实验（ ELISA）检测治疗前后患者外周静脉血清S100B水平。结果与各组治疗前相比,B组、C组及D组治疗后的MMSE和MoCA评分有提高,外周静脉血清S100B水平降低,但以D组各指标差异有统计学意义（均P＜0．05）。结论银杏叶联合认知治疗能够有效改善COPD患者的认知功能,可能与降低患者血清中S100B水平有关。     

Cognitive effects of a Ginkgo biloba/vinpocetine compound in normal adults: systematic assessment of perception,attention and memory

A computerized test battery was used in a double-blind design to assess the cognitive effects of a nutrient compound containing Ginkgo biloba in 24 normal adults. Ten tasks (perceptual, attention and short-term memory) were presented in a standardized manner designed to maximize performance, with substantial pre-test practice employed to minimize response variability. Subjects were given either placebo or Ginkgo biloba extract capsules to consume for 14 days, after which they performed all tasks twice. They then received the other condition, and after 14 days completed the final test session. Response time and error rate stabilized after pre-test practice. A 'working memory capacity' paradigm demonstrated a reliable 50 ms response time decrease between the placebo and Ginkgo biloba testing, suggesting that Ginkgo biloba speeds short-term working memory processing in normal adults. Copyright 2001 John Wiley & Sons, Ltd.     

银杏叶提取工艺的研究

对银杏叶提取物的提取和精制工艺进行了研究，确定了提取溶剂、时间、次数及浓缩、干燥温度等提取工艺参数。比较了树脂吸附一次洗脱和二次洗脱以及超滤与树脂吸附相结合的精制工艺对产品质量及总黄酮收率的影响。结果表明，超滤与树脂吸附工艺所得产品的质量和收率最佳。     

Identification of kaempferol as a monoamine oxidase inhibitor and potential Neuroprotectant in extracts of Ginkgo biloba leaves

The effects of Ginkgo biloba leaf extract on rat brain or livermonoamine oxidase (MAO)-A and -B activity, biogenic amine concentration in nervous tissue, N-methyl-D-aspartate (NMDA)- and N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4)-induced neurotoxicity and antioxidant activity was investigated to determine the effects of the extract on monoamine catabolism and neuroprotection. Ginkgo biloba leaf extract was shown to produce in-vitro inhibition of rat brain MAO-A and -B. The Ginkgo biloba extract was chromatographed on a reverse-phase HPLC system and two of the components isolated were shown to be MAO inhibitors (MAOIs). These MAOIs were identified by high-resolution mass spectrometry as kaempferol and isorhamnetin. Pure kaempferol and a number of related flavonoids were examined as MAOIs in-vitro. Kaempferol, apigenin and chrysin proved to be potent MAOIs, but produced more pronounced inhibition of MAO-A than MAO-B. IC50 (50% inhibition concentration) values for the ability of these three flavones to inhibit MAO-A were 7 x 10(-7), 1 x 10(-6) and 2 x 10(-6) M, respectively. Ginkgo biloba leaf extract and kaempferol were found to have no effect ex-vivo on rat or mouse brain MAO or on concentrations of dopamine, noradrenaline, 5-hydroxytryptamine and 5-hydroxyindoleacetic acid. Kaempferol was shown to protect against NMDA-induced neuronal toxicity in-vitro in rat cortical cultures, but did not prevent DSP-4-induced noradrenergic neurotoxicity in an in-vivo model. Both Ginkgo biloba extract and kaempferol were demonstrated to be antioxidants in a lipid-peroxidation assay. This data indicates that the MAO-inhibiting activity of Ginkgo biloba extract is primarily due to the presence of kaempferol. Ginkgo biloba extract has properties indicative of potential neuroprotective ability.     

Ginkgo biloba leaf extract reverses amyloid beta-peptide-induced isoprostane production in rat brain in vitro

Isoprostanes are prostaglandin (PG) isomers generated from oxygen radical peroxidation of arachidonic acid, which are reliable markers of membrane oxidative damage. Aging is characterized by an imbalance between the generation of reactive oxygen species and antioxidant detoxification pathways. Ginkgo biloba leaf extract is reputed as a neuroprotective antioxidant agent. We have tested the effects of a Ginkgo biloba extract {containing 24.1 % flavonoids and 181 % terpene lactones [bilobalide (0.542 %), ginkgolide A (0.570 %), ginkgolide B (0.293 %), ginkgolide C (0.263 %), and ginkgolide J (0.138 %)]} on the production of 8-iso-PGF2alpha from rat brain synaptosomes obtained from young (3 months old) or aged (12 and 24 months old) rats, both in the basal state and after oxidative stress induced by either hydrogen peroxide or amyloid beta-peptide. Our findings show that Ginkgo biloba extract pretreatment is able to completely reverse both basal and hydrogen peroxide-stimulated isoprostane production (IC50 of 81.92 microM and 31.89 microM, respectively). Amyloid beta-peptide-induced isoprostane production was also inhibited, both in young and aged rats, to a level even lower than that in unstimulated synaptosomes. This suggests that the oxygen radical scavenging properties of the Ginkgo biloba extract are fully effective in young, as well as in old rats, showing a greater inhibition of isoprostane production in the latter.     

复方心安软胶囊质量标准研究

目的:建立复方心安软胶囊的质量标准。方法:采用薄层色谱法对丹参、三七和银杏叶进行定性鉴别;采用高效液相色谱法对制剂中的丹参素钠进行含量测定。结果:定性鉴别阴性无干扰,分离度高。丹参素钠检测浓度在10.0～100.0μg·mL-1范围内与峰面积积分值呈良好线性关系;平均回收率为98.45%,RSD=0.44%(n=6)。结论:所建标准可用于复方心安软胶囊的质量控制。