密闭式微波降解法促进常见人参皂苷向稀有人参皂苷转化的规律

采用密闭微波技术对7种常见人参皂苷单体(Rb1,Rb2,Rb3,Rc,Rd,Re和Rg1)进行降解,通过高效液相色谱(HPLC)分析并与相同条件下非微波降解物对比,研究了密闭微波降解人参皂苷的产物在化学结构及组成上的变化规律,以期快速、高效地制备生物活性高的稀有人参皂苷.结果表明,密闭式微波降解法能够使常见人参皂苷基本降解完全,而相同条件下非微波降解法则基本不发生降解.原人参二醇型人参皂苷易水解掉C20位糖,并发生C20位构型变化,生成20(R)-Rg3和20(S)-Rg3,其中20-(R)为优势构型,C20位羟基进一步脱水产生稀有人参皂苷Rk1和Rg5.同时,20(S/R)-Rg3失去C3位的1分子葡萄糖转化为20(S/R)-Rh2,C20位羟基再进一步脱水生成了Rk2和Rh3.此外,人参皂苷C20位所连的糖种类与构型影响了降解产物中各稀有皂苷的组成与比例,但7种原人参二醇型人参皂苷密闭式微波降解产物中Rg5含量均为最高.密闭式微波降解对原三醇型人参皂苷的转化作用与原二醇型人参皂苷具有相似的规律,人参皂苷Re和Rg1的密闭式微波降解产物中Rh4含量均为最高.本文结果进一步说明在相同的降解条件下,密闭式微波降解法的降解效率远高于高温高压非微波降解法,密闭式微波降解可明显促进常见人参皂苷向稀有人参皂苷转化,因此采用密闭微波技术对常见人参皂苷进行降解可以大量获得稀有人参皂苷.     

人参中达玛烷型皂苷的化学转化产物结构和转化途径研究

利用高效液相色谱-电喷雾-多级串联质谱(HPLC-ESI-MSn)技术分析人参中3种达玛烷型皂苷(三七皂苷R1,人参皂苷Rd、20(S)-Rg3)在12-磷钨酸环境中转化的产物结构和转化途径。由原人参三醇型皂苷R1转化获得9种产物:20(S)-25-OH-R2、20(R)-25-OH-R2、25-OH-T5、20(S)-R2、20(R)-R2、20(S)-25-epoxy-R2、20(R)-25-epoxy-R2、T5、3β,12β-二羟基-6α-(2-O-β-D-吡喃木糖基-β-D-吡喃葡糖氧基)达玛烷-20(22),24-二烯。由原人参二醇型皂苷Rd和20(S)-Rg3转化得到10种产物:20(S)-25-OH-Rg3、20(R)-25-OH-Rg3、25-OH-Rk1、25-OH-Rg5、20(S)-Rg3、20(R)-Rg3、(20S,25)-epoxy-Rg3、(20R,25)-epoxy-Rg3、Rk1、Rg5。通过分析转化产物结构,并考察主要产物含量随转化时间的变化趋势,总结了人参中达玛烷型皂苷在酸性水溶液环境中的转化途径,即通过C20位去糖基化和差向异构化反应,以及烯烃链的水合、脱水、环合反应转化为稀有皂苷。     

基于HPLC-HRMS/MS~n/QqQ技术的人参皂苷Rb_1化学转化产物的结构与途径分析

利用液相色谱-质谱联用技术分析了Keggin型12-磷钨酸化学转化人参皂苷Rb1产物的结构与转化途径.基于高效液相色谱对转化产物的快速分离,利用Q Exactive高分辨质谱的Full MS-AIF模式快速鉴定了产物结构,并利用多级串联质谱进行结构验证.进一步结合人参皂苷异构体在反向C18色谱柱上的相对保留时间,快速分析鉴定出Rb1的10种转化产物为20(S)-Rg3,20(R)-Rg3,20(S)-25-OH-Rg3,20(R)-25-OH-Rg3,25-OH-Rk1,25-OH-Rg5,Rg5,Rk1,(20S,25)-环氧-Rg3和(20R,25)-环氧-Rg3.根据转化产物的结构初步推断了人参皂苷的转化途径:在12-磷钨酸产生的酸性环境中,Rb1主要通过C20位去糖基化、差向异构化和烯烃链的水合、消除及环合反应转化为稀有皂苷.采用三重四极杆质谱的选择反应监测模式准确定量分析了Rb1的转化效率和稀有皂苷20(S)-Rg3,20(R)-Rg3,Rk1和Rg5的产率.定量分析结果显示,与生物转化相比,12-磷钨酸对Rb1有更高的转化效率,反应40 min后转化率达到100%.本文结果表明,HPLC-HRMS/MSn/Qq Q技术是人参皂苷等天然产物结构解析与定量分析的有效方法.     

人参中人参皂苷的直接高压微波辅助降解

采用高效液相色谱-电喷雾质谱联用法测定了人参提取液中的人参皂苷. 考察了天然人参皂苷发生降解的条件, 同时研究了单体人参皂苷Rg1, Re, Rb1, Rc, Rb2和Rd的降解, 并对降解产物进行了分析. 结果表明, 随着提取压力的升高, 提取液中天然人参皂苷的含量逐渐减少, 同时产生多种次级人参皂苷. 当微波提取压力达到600 kPa, 提取时间为10 min时, 提取液中的主要天然人参皂苷达到完全降解, 次级人参皂苷Rg3含量达到最高. 在单体人参皂苷Rb1, Rc, Rb2和Rd的降解产物中均得到人参皂苷Rg3.     

泡沫浮选-固相提取分离富集三七提取液中的人参皂苷

采用泡沫浮选-固相提取联用法,分离富集三七中的R1,Rg1,Re,Rc,Rb2,Rb3,Rd和Rb1,并用液相色谱法测定其含量,检测灵敏度和选择性都有所提高.对泡沫浮选过程的载气流量、浮选时间、样品溶液pH值和固相提取柱的洗脱条件进行了优化.原人参二醉型皂苷R1,Rc,Rb2,Rb3,Rd和Rb1的回收率在85.0%9...     

泡沫浮选法分离富集三七中的4种人参皂苷

采用泡沫浮选法对三七提取液中的人参皂苷Rg1、Re、Rb1和Rd进行了分离富集,并用高效液相色谱法分别测定了含量.考察了浮选液浓度、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响.结果表明:泡沫浮选法对4种皂苷均有较好的分离富集效果,尤其是对人参二醇型皂苷(Rb1,Rd)效果更为明显.当浮选液浓度为2.0 mg/mL,pH值为2～3,氮气流速为20 mL/min,浮选时间10 min,电解质氯化钠浓度0.20 mol/L,泡沫浮选效果最佳.     

高效液相色谱法测定竹节参中多种人参皂苷含量

建立了高效液相色谱法(HPLC)测定竹节参中人参皂苷Rg1、Re、Rb1、Rb2、Rg2、Rd含量的方法.运用二极管阵列检测器(DAD)峰纯度和光谱检索功能,结合保留时间定性,外标峰面积法定量.采用C18反相柱,以乙腈-水梯度洗脱测定了同一批竹节参总皂苷中人参皂苷Rg1、Re、Rd的含量分别为0.81%、0.15%、2.99%,回收率为93.46%~94.02%,含量及回收率的RSD均小于5%,该方法简便、灵敏,精密度及准确度在允许范围内,可作为竹节参皂苷提取物中多种人参皂苷的同时测定方法.     

在线二维柱切换高效液相色谱法同时测定牙膏中三七皂苷R1、人参皂苷Rg1、Re和Rb1

使用双梯度液相色谱系统紫外检测器,建立了二维液相色谱法全自动快速同时测定牙膏中三七皂苷R1、人参皂苷Rg1、Re和Rb1的含量。样品经超声提取后,以Syncronis C18为一维分析柱,ODS C18为二维分析柱,利用一维色谱柱完成三七皂苷R1和人参皂苷Rb1分离测定以及人参皂苷Rg1和人参皂苷Re的净化;利用二维色谱柱完成人参皂苷Rg1和人参皂苷Re的分析。一维分析和二维分析均以乙腈-水体系作为流动相,梯度洗脱,检测波长为203 nm,整个分析过程仅需30 min。三七皂苷 R1、人参皂苷 Rg1、Re 和 Rb1在0.5~200 mg/L范围内线性良好,相关系数R2分别为0.9994,0.9996,0.9995和0.9994,平均回收率均在86.4％~95.1％之间。本方法简便快速,测定结果准确可靠,可用于牙膏中三七皂苷R1、人参皂苷Rg1、Re和Rb1含量的测定。     

微生物酶催化制备人参皂苷20(S)-Rg2,20(S)-Rh1和20(S)-PPT

摘要 人参次级皂苷具有较强的抗癌、抗癌转移等药理活性,但由于在人参中含量少或不存在,因此以人参中含量较高的主要人参皂苷制备药效更高的人参次级皂苷不仅有必要,而且很有意义．本文以微生物Microbacterium esteraromaticum GS514的培养液中分离的粗酶为催化剂水解人参皂苷Re和Rg1,并通过1H NMR和13C NMR谱进行了水解产物的结构表征．实验结果表明,反应体系中无机盐NaCl的存在与否直接影响人参皂苷Re,Rg1与粗酶液的反应结果.人参皂苷与粗酶液直接反应,人参皂苷Re不发生反应,人参皂苷Rg1通过C6所连β-D-吡喃葡萄糖的选择性水解转化成人参皂苷F1.如果该反应是在无机盐NaCl存在下进行,人参皂苷Re通过对C20 所连β-D-吡喃葡萄糖的选择性水解定向转化为20(S)-人参皂苷Rg2;人参皂苷Rg1定向转化成20(S)-人参皂苷Rh1以及20(S)-原人参三醇（PPT）.这说明NaCl的加入激活了C20β-D-吡喃葡萄糖苷酶的活性,这对定向合成不同次级人参皂苷具有重要意义.     

改性松香键合二氧化硅高效液相色谱固定相的制备及其对三七总皂苷的分离

三七中发挥药效的主要成分为三七皂苷R1、人参皂苷Rg1、人参皂苷Re、人参皂苷Rb1和人参皂苷Rd,用于贫血、冠心病、高血压、脑卒中后遗症等疾病的治疗,但其化学成分多且难分离.将氢化松香丙烯酸羟乙酯(HRHA)通过巯基-烯点击化学反应键合到烷基化硅胶表面,制备出一种新型的改性松香键合二氧化硅高效液相色谱固定相(SiO2...     

The in vitro structure-related anti-cancer activity of ginsenosides and their derivatives

Panax ginseng has long been used in Asia as a herbal medicine for the prevention and treatment of various diseases, including cancer. The current study evaluated the cytotoxic potency against a variety of cancer cells by using ginseng ethanol extracts (RSE), protopanaxadiol (PPD)-type, protopanaxatriol (PPT)-type ginsenosides fractions, and their hydrolysates, which were prepared by stepwise hydrolysis of the sugar moieties of the ginsenosides. The results showed that the cytotoxic potency of the hydrolysates of RSE and total PPD-type or PPT-type ginsenoside fractions was much stronger than the original RSE and ginsenosides; especially the hydrolysate of PPD-type ginsenoside fractions. Subsequently, two derivatives of protopanaxadiol (1), compounds 2 and 3, were synthesized via hydrogenation and dehydration reactions of compound 1. Using those two derivatives and the original ginsenosides, a comparative study on various cancer cell lines was conducted; the results demonstrated that the cytotoxic potency was generally in the descending order of compound 3 > 20(S)-dihydroprotopanaxadiol (2) > PPD (1) > 20(S)-Rh2 > 20(R)-Rh2 ≈ 20(R)-Rg3 ≈ 20(S)-Rg3. The results clearly indicate the structure-related activities in which the compound with less polar chemical structures possesses higher cytotoxic activity towards cancer cells.     

高效液相色谱-二极管阵列检测/质谱法分析生脉饮煎剂中的人参皂甙类成分

采用高效液相色谱-二极管阵列检测/质谱（HPLC-DAD/MS）联用技术,以10 mmol/L醋酸铵和乙腈混合溶液梯度洗脱 系统为流动相,应用C18色谱柱对生脉饮煎剂中人参皂甙类成分进行分离鉴定。分析结果表明:生脉饮煎剂中主要含有17个 人参皂甙类成分,即20(R)-人参皂甙Rh1、Rh2、Rg3、Rg2,20(S)-人参皂甙Rh1、Rh2、Rg3、Rg2,人参皂甙Rf、Rg6、Rg5 、F4、Rk1、Rk3、Rh4,20(S)-和20(R)-原人参三醇。人参皂甙成分在煎煮过程中发生了很大变化,主要变成了一些中低 极性产物,这是因为煎煮过程中发生了水解、差向异构、脱水等反应。该方法简便、精确、灵敏度高,可以用来分析生脉 饮煎剂中人参皂甙的变化。     

Determination of Seven Major Ginsenosides in Different Parts of Panax quinquefolius L.(American Ginseng) with Different Ages

Ginsenosides Rg1,Re,Rb1,Rc,Rb2,Rb3,and Rd in different parts of the American ginseng plant were investigated.The extraction process was a pressurized microwave-assisted extraction(PMAE).The seven ginsenosides were separated and determined by high-performance liquid chromatography(HPLC) with a ultraviolet(UV) detector,at 203 nm.The experiment results showed significant variations in the individual ginsenoside contents of the American ginseng in different parts and ages of the plant.The results demonstrated that the leaves,root hairs,and rhizomes of Panax quinquefolius L.contained higher ginsenoside contents,followed by the main roots and stems.The leaves contained dramatically higher levels of ginsenoside Rg1,Rb3,and Rd than the other four parts.Higher contents of Rb1 and Re were present in the main roots,root hairs,and rhizomes.The amount of ginsenoside content in the stems was the lowest.The total content of the seven ginsenosides in main roots,root hairs and rhizomes increased with the age of the plant.In contrast,the ginsenoside contents in the leaves and stems decreased with a year of growth.     

动态泡沫浮选法分离富集人参提取液中的二醇型人参皂苷

采用动态泡沫浮选法分离富集人参提取液中的二醇型人参皂苷, 用高效液相色谱法测定6种人参皂苷Rg₁, Re, Rb₁, Rc, Rb₂和Rd的含量. 考察了浮选液pH值、电解质NaCl浓度、载气流量、料液浓度及料液流速对人参皂苷浮选率的影响, 确定了动态泡沫浮选的最佳条件, 并与溶剂提取法、溶剂浮选法以及静态泡沫浮选法进行了比较. 结果表明, 动态泡沫浮选法对二醇型人参皂苷Rb₁, Rc, Rb₂和Rd具有高富集效率, 回收率分别为93.3%, 98.6%, 96.9%和98.3%, 而对三醇型人参皂苷Rg1和Re的富集效率却很低, 回收率分别为4.8%和4.2%. 该法是分离纯化二醇型人参皂苷的一种简便有效的方法.     

Analysis of Low-polar Ginsenosides in Steamed Panax Ginseng at High-temperature by HPLC-ESI-MS/MS

A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrometry( HPLC-ESI-MS/MS) method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng(RPG) and steamed Panax ginseng at high temperatures(SPGHT). A total of 25 ginsenosides were extracted include of which 10 low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 20S-Rg3, 20R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1, Rb1, Rc, Rb2, Rb3 and Rd were selected and hydrolyzed at a temperature of 120 ℃. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2, Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains.     

Six new dammarane-type triterpene saponins from the leaves of Panax ginseng

Six new minor saponins, together with known ginsenosides, were isolated from the leaves of Panax ginseng. The new saponins were named as ginsenoside-Rh5, -Rh6, -Rh7 -Rh8, -Rh9 and -Rg7, and their structures were elucidated on the basis of chemical and physicochemical evidence to be as follows: ginsenoside-Rh5: 3beta,6alpha,12beta,24zeta-tetrahydroxy-dammar-20(22),25-diene 6-O-beta-D-glucopyranoside (1), -Rh6: 3beta,6alpha12beta,20(S)-tetrahydroxy-25-hydroperoxy-dammar-23-ene 20-O-beta-D-glucopyranoside (2), -Rh7: 3beta,7beta,12beta,20(S)-tetrahydroxy-dammar-5,24-diene 20-O-beta-D-glucopyranoside (3), -Rh8: 3beta,6alpha,20(S)-trihydroxy-dammar-24-ene-12-one 20-O-beta-D-glucopyranoside (4), -Rh9: 3beta,6alpha,20(S)-trihydroxy-12beta,23-epoxy-dammar-24-ene 20-O-beta-D-glucopyranoside (5) and -Rg7: 3-O-beta-D-glucopyranosyl 3beta,12beta,20(S),24(R)-tetrahydroxy-dammar-25-ene 20-O-beta-D-glucopyranoside (6).     

Determination of ginsenoside content in Asian and North American ginseng raw materials and finished products by high-performance liquid chromatography: single-laboratory validation

A single-laboratory validation study was conducted for the quantification of Rg1, Re, Rb1, Rc, Rb2, and Rd in Asian ginseng (Panax ginseng C.A. Meyer) and North American ginseng (Panax quinquefolius L.) raw materials and finished products by RP-HPLC. The extraction with aqueous methanol was optimized for whole root, powdered extract, and finished product (raw, tablet, and capsule matrixes) test articles. Root materials were treated with base to hydrolyze acidic malonyl ginsenosides to their neutral counterparts. Calibration curves for each ginsenoside were linear over the following ranges (microg/g): 5-394 for Rg1, 15-1188 for Re, 39-2981 for Rb1, 6-499 for Rc, 5-406 for Rb2, and 7-600 for Rd, all having a coefficient of determination (r2) of > or = 99.5%. The LOD for Rg1, Re, Rb1, Rc, Rb2, and Rd was determined to be 1.06, 1.25, 2.19, 1.24, 1.27, and 1.70 microg/mL, respectively. Quantitative determinations performed with eight test materials by two analysts over 3 days (n = 12) resulted in RSDr values that ranged from 1.11 to 7.61%.     

Chemical characteristics of three medicinal plants of the Panax genus determined by HPLC-ELSD

The morphological appearance and main ingredients of three Chinese medicines (CMs), P. ginseng, P. quinquefolius, and P. notoginseng of the Panax genus, are similar. However, their pharmacological activities are obviously different. To ensure their safety and efficacy, chemical characteristics of the three CMs were determined using pressurized liquid extraction and HPLC-evaporative light scattering detection. Twelve major saponins, namely notoginsenoside R1, pseudo-ginsenoside F11, ginsenosides Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, Rb3, Rd, and Rg3 were also quantitatively compared among the three CMs. The contents of total investigated saponins varied considerably, by up to 4-14-fold, between the highest (P. notoginseng, 82.8-136.5 mg/g) and the lowest values (P. ginseng, 10.0-21.1 mg/g). Hierarchical clustering analysis based on the characteristics of 11 investigated saponins (except ginsenoside Rb3) and notoginsenoside R1, pseudo-ginsenoside F11, and the ratio of ginsenoside Rg1/Rb1 and Rg1/Re showed that 56 tested samples were divided into three main clusters in accordance with the three Panax species. Similarity evaluation of chromatograms was also performed using "Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine (Version 2004A)". The results showed that a high degree of similarity existed within individual clusters, but a low degree between the clusters, which could be used for quality control of the three CMs.     

Major ginsenoside contents in rhizomes of Panax sokpayensis and Panax bipinnatifidus

This study compared eight major ginsenosides (Rg1, Rg2, Rf, Re, Rd, Rc, Rb1 and Rb2) between Panax sokpayensis and Panax bipinnatifidus collected from Sikkim Himalaya, India. High-performance liquid chromatographic analysis revealed that all major ginsenosides were present in the rhizomes of P. sokpayensis except ginsenoside Rc, whereas ginsenoside Rf, Rc and Rb2 were not detected in P. bipinnatifidus.     

Determination of Seven Major Ginsenosides in Different Parts of Panax quinquefolius L.（American Ginseng） with Different Ages

Ginsenosides Rgl, Re, Rb1, Rc, Rb2, Rb3, and Rd in different parts of the American ginseng plant were investigated. The extraction process was a pressurized microwave-assisted extraction（PMAE）. The seven ginsenosides were separated and determined by high-performance liquid chromatography（HPLC） with a ultraviolet（UV） detector, at 203 nm. The experiment results showed significant variations in the individual ginsenoside contents of the American ginseng in different parts and ages of the plant. The results demonstrated that the leaves, root hairs, and rhizomes of Panax quinquefolius L. contained higher ginsenoside contents, followed by the main roots and stems. The leaves contained dramatically higher levels of ginsenoside Rg1 Rb3, and Rd than the other four parts. Higher contents of Rb1 and Re were present in the main roots, root hairs, and rhizomes. The amount of ginsenoside content in the stems was the lowest. The total content of the seven ginsenosides in main roots, root hairs and rhizomes increased with the age of the plant. In contrast, the ginsenoside contents in the leaves and stems decreased with a year of growth.