测定橘核中柠檬苦素类似物的分光光度法

建立了一种以柠檬苦素为标样快速简便地测定柠檬苦素类化合物总量的方法。测定过程包括用石油醚去油 ,然后用丙酮提取柠檬苦素类似物 ,再用二氯甲烷萃取丙酮提取物 ,最后根据柠檬苦素和Ehrlich试剂的反应来测定柠檬苦素类似物的总量。得出的回归方程为 y= -0.0163 0.003676x,检出限为7×10-6 。应用该法测定了4个样品 ,回收率在99.4%～100.1%范围内。实验表明该反应的选择性、重现性和对照性均好 ,操作方便 ,适用于柠檬苦素类似物提取过程中的常规检测。     

高效液相色谱法测定柑橘汁中的柠檬苦素和柚皮苷

柑橘汁的苦味主要是由于柚皮苷和柠檬苦素的存在所致,其含量的测定可用于控制柑橘类果汁的质量。采用高效液相色谱法在KR100-5C18(4.6 mm i.d.×250 mm,5 μm)上,分别以乙腈-四氢呋喃-水(体积比为17.5∶17.5∶65)和甲醇-冰醋酸-水(体积比为40∶1∶59)为流动相（流速均为1 mL/min）,在207 nm和283 nm检测波长下分别测定了柠檬苦素和柚皮苷。实验结果表明,柠檬苦素在1.00～50.00 mg/L时线性关系良好(r=0.9992),检出限为0.07 μg,平均加标回收率为98.69%,相对标准偏差（RSD）为2.5%;柚皮苷在20.00～160.00 mg/L时线性关系良好(r=0.9988),检出限为0.14 μg,平均加标回收率为100.13%,RSD为1.5%。用该法检测柑橘汁样品中的柠檬苦素与柚皮苷,方法简便、快速、准确。     

吸附树脂分离纯化柚核中的柠檬苦素

比较了大孔吸附树脂AB-8、HZ-816、HZ-818、HZ-803、HZ-806、D101对柠檬苦素的吸附性能,筛选出最佳树脂HZ-816进行柠檬苦素的分离纯化实验。实验表明,HZ-816能有效的吸附和解析柚核中的柠檬苦素,并确定了最佳工艺参数。柠檬苦素样品溶液经HZ-816树脂吸附与脱附后回收率为60%,含量由2.1%提高到47.1%,提高了22倍。     

液相色谱/电喷雾质谱测定柑桔中的柠檬苦素类似物配糖体

 利用液相色谱 /电喷雾质谱联用技术对柚皮中的柠檬苦素类似物配糖体进行了定向分析 ,在柚皮的乙醇提取物中检测出奥巴叩酮配糖体和诺米林配糖体。利用制备液相色谱对这两种柠檬苦素类似物配糖体进行纯化 ,并用核磁共振对其结构进行鉴定。测定结果表明 ,液质联用法不需标样即可对柑桔中的柠檬苦素类似物配糖体进行定性分析。方法准确、快速、简便。     

蔬毛吴茱萸果实中新化合物吴茱萸塔宁的分离及结构表征

从传统中药蔬毛吴茱萸的干燥未成熟果实中分离得到一个稀有高氧化状态、新的柠檬苦素类化合物吴茱萸塔宁(evolimorutanin),同时还分离得到了已知结构的化合物柠檬苦素(limonin)。根据IR、MS、1DNMR(1HNMR,13C NMR,DEPT)和2D NMR(1H-1HCOSY,HSQC,HMBC)谱学数据确定了它们的结构,两者均归属为降三萜类化合物,A,A′,B,C,D五个环的取代和立体构型完全相同,只有E环氧化状态不同。此外,还分析了从柠檬苦素转化为吴茱萸塔宁的可能过程。     

高效液相色谱法测定木瓜素含片中木糖醇的含量

用高效液相色谱法测定木瓜素中木糖醇的方法,采用Waters碳水化合物柱(4.6 mm×250 mm),用乙腈∶水(85∶15)作为流动相,示差检测器检测.该方法平均回收率为99.0%,RSD为2.2%,操作简便,结果满意.     

高效液相色谱法测定五味子和含五味子的制剂中五味子乙素及多种活性成分时流动相体系的选择

建立了用高效液相色谱法测定五味子和含五味子的制剂中五味子乙素的流动相体系。用Shim-pack VP-ODS (250 mm×4.6 mm,5 μm)色谱柱,在柱温30 ℃、检测波长285 nm、流速1.0 mL/min的条件下,用不同的流动相组成及其不同比例研究了五味子提取液中3种木脂素(五味子乙素、安五脂素和五味子甲素)的保留时间及其分离情况,从中选择测定五味子乙素的最佳流动相体系。结果表明,在甲醇-水、甲醇-冰醋酸-水的流动相体系中,安五脂素和五味子乙素很难完全分离;而在乙腈-甲醇-水和乙腈-冰醋酸-水流动相体系中,3种木脂素可很好地分离。以乙腈-甲醇-水(体积比为17:58:25)为流动相测定五味子和护肝片中3种木脂素的含量,相对标准偏差(n4)为0.95%～5.8%,平均加标回收率为94.50%～105.6%。将该流动相体系用于供试品中3种木脂素含量的测定,分离效果好,结果令人满意。     

反相液相色谱法制备纯化柠檬苦素类似物配糖体

 利用反相制备液相色谱结合吸附树脂柱色谱和离子交换色谱方法 ,从甜橙种子的提取物中纯化制备了一种柠檬苦素类似物配糖体 ,经 NMR测定为奥巴叩酮配糖体。     

分散液液微萃取-气相色谱-质谱法测定水样中4种嗅味物质

以四氯乙烯作萃取剂,以丙酮为分散剂对水样中4种嗅味物质,二甲基异莰醇、土臭素、β-环柠檬醛和β-紫罗兰酮进行分散液液微萃取,提取液供气相色谱-质谱仪分析。在选择离子监测模式下,4种嗅味物质的线性范围均为0.05～20μg.L-1。二甲基异莰醇、土臭素、β-环柠檬醛和β-紫罗兰酮的检出限(3S/N)分别为0.03,0.01,0.02,0.01μg.L-1。方法用于自来水和河水样品分析,4种嗅味物质的回收率在87.7%～102%之间,测定值的相对标准偏差(n=6)在1.8%～7.8%之间。     

Perforanoid A的分离和不对称全合成

正Angew.Chem.Int.Ed.2016,55,7539~7543柠檬苦素具有丰富的骨架类型和多种生物活性,其全合成受到有机化学家的广泛关注.中国科学院昆明植物研究所郝小江课题组从苦木科植物牛筋果[Harrisonia perforata(Blanco)Merr.]中分离得到了一个结构新颖的柠檬苦素perforanoid A.由于NOSEY信号重叠严重,分离得到的样品量少且未能得到单晶,未能确证其C(10)位的立体构型.     

Determination of limonin in dog plasma by liquid chromatography–tandem mass spectrometry and its application to a pharmacokinetic study

A highly sensitive liquid chromatography–tandem mass spectrometry method was developed and validated for the determination of limonin in beagle dog plasma using nimodipine as internal standard. The analyte and internal standard (IS) were extracted with ether followed by a rapid isocratic elution with 10 mm ammonium acetate buffer–methanol (26:74, v/v) on a C₁₈ column (150 × 2.1 mm i.d.) and subsequent analysis by mass spectrometry in the multiple reaction monitoring mode. The precursor to product ion transitions of m/z 469.4 → 229.3 and m/z 417.2 → 122.0 were used to measure the analyte and the IS. The assay was linear over the concentration range of 0.625–100 ng/mL for limonin in dog plasma. The lower limit of quantification was 0.312 ng/mL and the extraction recovery was >90.4% for limonin. The inter‐ and intra‐day precision of the method at three concentrations was less than 9.9%. The method was successfully applied to pharmacokinetic study of limonin in dogs. Copyright © 2012 John Wiley & Sons, Ltd.     

A sensitive liquid chromatographic-mass spectrometric method for simultaneous determination of dehydroevodiamine and limonin from Evodia rutaecarpa in rat plasma

A liquid chromatographic–mass spectrometric (LC–MS) method has been developed and validated for simultaneous determination of dehydroevodiamine and limonin from Evodia rutaecarpa in rat plasma. After addition of the internal standard, domperidone, plasma samples were extracted by liquid–liquid extraction with ethyl acetate and separated on an Apollo C₁₈ column (250 mm × 4.6 mm, 5 μm), with methanol–0.01% formic acid water (60:40, v/v) as mobile phase, within a runtime of 12.0 min. The analytes were detected without interference in the selected ion monitoring (SIM) mode with positive electrospray ionization. The linear range was 1.0–500 ng mL⁻¹ for dehydroevodiamine and 2.0–1,000 ng mL⁻¹ for limonin, with lower limits of quantitation of 1.0 and 2.0 ng mL⁻¹, respectively. Intra-day and inter-day precision were within 6.0% and 10.9%, respectively, for both analytes, and the accuracy (relative error, RE, %) was less than 4.8% and 6.5%, respectively. The validated method was successfully applied to a comparative pharmacokinetic study of dehydroevodiamine and limonin in rat plasma after oral administration of dehydroevodiamine, limonin, and an aqueous extract of Evodiae fructus. The results indicated there were obvious differences between the pharmacokinetic behavior after oral administration of an aqueous extract of Evodiae fructus compared with single substances.     

高效液相色谱法测定平胃丸中橙皮苷的含量

提出了高效液相色谱法测定平胃丸中橙皮苷含量的方法。采用Hypersil BDS C18(200mm×4.6mm,5μm)色谱柱;以甲醇-乙酸-水(35+4+61)混合溶液为流动相,流量1mL.min-1,检测波长为283nm,橙皮苷的质量浓度与峰面积在8.08～121.2mg.L-1范围内呈线性关系。方法用于平胃丸中橙皮苷的测定,平均回收率为101.1%,相对标准偏差(n=9)为1.2%。     

Determination of limonin in grapefruit juice and other citrus juices by high-performance liquid chromatography

A method has been developed for the quantitation of the bitter component limonin in grapefruit juice and other citrus juices. The sample clean-up consisted of centrifugation, filtration and a selective, rapid and reproducible purification with a C2 solid-phase extraction column. The limonin concentration was determined by high-performance liquid chromatography on a C18 column with UV detection at 210 nm. A linear response was obtained from 0.0 to 45 ppm limonin. The minimum detectable amount was 2 ng. The minimum concentration which was detected without concentration with good precision was 0.1 ppm. The method was also used for the determination of limonin in different types of oranges, including navel oranges, mandarins, lemons, limes, pomelos and uglis.     

High-performance liquid chromatography quantitation of limonin D-ring lactone hydrolase and limonoate dehydrogenase activities

Ion-pairing reversed-phase HPLC has been used to separate and determine different derivatives of limonin, i.e. disodium limonoate, 17-dehydrolimonoate, limonoate A-ring lactone and 17-dehydrolimonoate A-ring lactone. Consequently, it has been possible to measure, by this chromatographic technique, the activities of the two enzymes that sequentially catalize the first two steps in limonin degradation: limonin D-ring lactone hydrolase and limonoate dehydrogenase. In both cases linear responses were found when using increasing enzyme amounts. The determination of limonoate dehydrogenase by HPLC measurements of limonoid products was compared with that obtained by the spectrophotometric method, based on pyridine nucleotides reduction. A good correlation was detected by using both procedures, which allows the proposition of the chromatographic method as an alternative to pyridine nucleotides determination. Besides, the chromatographic method appears to be a better assay than thin-layer chromatography or radioactive procedures, the methods traditionally used to measure limonin D-ring lactone hydrolase activity.     

高效液相色谱法分析硫双灭多威

研究了用高效液相色谱分析杀虫剂硫双灭多威的方法。在反相ＯＤＳ柱上,用甲醇－水作流动相,紫外检测器检测,以邻苯二甲酸二甲酯作内标定量。方法快速、准确,重现性好,线性范围宽,变异系数为０．１８％,回收率为９９．８９％,色谱分析周期仅为８ｍｉｎ。     

高效液相色谱法测定柑橘皮中新橙皮苷

提出了高效液相色谱法测定柑橘皮中新橙皮苷含量的方法。样品用甲醇超声提取,定容至50mL。以SinoChrom ODS-BP色谱柱(250mm×4.6mm,10μm)为分离柱,以甲醇-水(36+64)溶液作为流动相,用紫外检测器在波长283nm处进行测定。新橙皮苷质量浓度在0.005 3～0.32g.L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为0.6mg.L-1。方法的平均回收率为90.3%,相对标准偏差(n=6)为1.7%。     

超高效液相色谱-串联质谱法测定食用植物油中胆固醇含量

提出了食用植物油中胆固醇的超高效液相色谱-串联质谱测定方法。食用植物油经皂化后用石油醚-乙醚(1+1)溶液提取,以Waters ACQUITY UPLC BEH C18色谱柱(50mm×2.1mm,5μm)为分离柱,以甲酸-甲醇(0.1+99.9)溶液为流动相,以2,2,3,4,4,6-d6胆固醇为内标,采用大气压化学电离源在多反应监测负离子模式下进行测定,胆固醇和内标的定量离子对分别为m/z369.2/146.9,369.2/160.9和375.2/166.5。胆固醇在0.1～5mg·L-1范围内呈线性,测定下限(10S/N)为0.02ng。在3个浓度水平上对方法做回收试验,测得回收率在102%～110%之间。     

HPLC法测定氯霉素氢化可的松滴耳液中两组分的含量

采用反相高效液相色谱法,以醋酸泼尼松为内标,ＵＶ检测波长为２４４ｎｍ,以ＹＷＧ－Ｃ１８为固定相,以甲醇－水（６０∶４０）为流动相,同时测定了氯霉素氢化可的松滴耳液中氯霉素和氢化可的松的含量,并进行了线性范围和回收率测定,平均回收率（ｎ＝６）和相对标准偏差分别为：９９．９１％和０．８６％（氯霉素）,９９．５８％和１．３４％（氢化可的松）。