人参生殖器官皂苷含量动态变化

为了明确从现蕾、开花到结实过程中的人参生殖器官中各单体皂苷含量的动态变化,应用HPLC法测定了人工栽培的五年生人参不同时期生殖器官中的人参单体皂苷Rb1、Rb2、Rb3、Rc、Rd、Re、Rg1和Rg3的含量。结果显示:从现蕾到果实成熟的过程中,人参单体皂苷Rb1、Rb2、Rb3、Rc、Rd、Re、Rg1和Rg3的含量的平均值分别为0.643%,0.189%,1.026%,1.014%,1.941%,8.381%,0.724%和0.041mg.g-1。从现蕾到果实成熟的过程中,人参单体皂苷Rb1含量的最高值在7月16日,单体皂苷Rb3、Rc、Rd和Rg1含量的最高值在7月11日,单体皂苷Rb2和Rg2含量的最高值在8月7日。     

西洋参总皂苷酶水解产物成分研究

西洋参总皂苷经β-糖苷酶催化水解,采用HPLC检测分析确定西洋参总皂苷中的主要原人参二醇型皂苷Rb1、Rd、Rc和Rb2已经完全被水解。水解产物通过反复硅胶柱层析和反向硅胶柱层析分离纯化得到7个皂苷,通过NMR谱图分析分别鉴定为人参皂苷compound K(1)、人参皂苷Mc(2)、人参皂苷Rg1(3)、人参皂苷Rg2(4)、人参皂苷Re(5)、人参皂苷F1(6)和拟人参皂苷F11(7)。β-糖苷酶催化西洋参总皂苷水解实验表明,西洋参中原人参二醇型皂苷的水解产物是人参皂苷compound K和人参皂苷Mc。     

小型生物反应器内人参不定根的人参皂苷累积

对小型生物反应器(3~10 L)培养人参不定根的生长和人参皂苷(Rg1、Re、Rb1)的累积规律,以及蔗糖浓度、初始接种量对其生长和人参皂苷累积的影响进行研究。结果表明:小型生物反应器内人参不定根的最佳收获周期为7周。初始接种量和蔗糖浓度影响生物反应器内人参不定根的生长和人参皂苷的累积,20或40 g/L蔗糖对人参不定根的生长和人参皂苷的累积优于60 g/L蔗糖;5和10 L生物反应器内最佳初始接种量分别为15和30g,其不定根的生长量分别为9.29和19.17 g,人参皂苷含量分别为5.16和4.58 mg/g。生物反应器内培养7周的人参与栽培4年的人参相比,人参皂苷Rg1和Re含量相差不大,但栽培人参中Rb1的含量远高于生物反应器中所培养的人参不定根。     

三七叶、人参叶和西洋参叶皂苷类成分的研究(英文)

三七叶、人参叶和西洋参叶其皂苷类成分相近,但专属性成分各异,皂苷类成分的分布比例也各不相同。本文建立了HPLC-UV法测定上述皂苷成分的方法,经过方法学考察,各种皂苷成分精密度好、加样回收率高,方法可靠。11种皂苷成分总含量顺序为:西洋参叶>人参叶>三七叶;二醇组皂苷成分含量:西洋参叶>三七叶>人参叶;三醇组皂苷成分含量:人参叶>西洋参叶>三七叶。西洋参叶中二醇组皂苷和人参叶中三醇组皂苷含量明显高于其他。西洋参叶中人参皂苷Rb3和Rd的含量之和占11种皂苷成分的60%以上。鉴于其中人参皂苷的高含量,三七叶、人参叶和西洋参叶应该作为皂苷来源得到充分利用;不同的皂苷成分有不同的药理活性,应基于它们的皂苷组成和比例选择性进行研究和开发。     

HPLC法同时测定人参皂苷Rb1、Rc、Rd、Rg3、CK和Rh2

目的:建立高效液相色谱法同时测定人参皂苷Rb1、Rc、Rd、Rg3、CK和Rh2的方法.方法:采用ODSC18(4.6 mm×150 mm)色谱柱,流动相乙腈-0.05%磷酸水,梯度洗脱,流速1 Ml/min,检测波长203 nm,柱温35 ℃.结果:人参皂苷Rb1、Rc、Rd、Rg3、CK和Rh2分离效果良好,线性关...     

西洋参冠瘿组织培养及其人参皂苷Re和人参皂苷Rg1的产生

考察了培养基组成、培养时间、接种量、pH值、肌醇浓度等对冠瘿组织生长及其人参皂苷含量的影响 ;用HPLC检测了冠瘿组织中人参皂苷Re和人参皂苷Rg1 的含量。高压纸层析电泳证实 ,根癌农杆菌Ti质粒上的T DNA片段已整合进入植物细胞核基因组中。在考察的 6种培养基中 ,White培养基最适合人参皂苷Rg1 的累积(0 0 95 % ) ,MS培养基最适合人参皂苷Re的累积 (0 194 % )。以MS为基本培养基培养 36d、32d时人参皂苷Re和人参皂苷Rg1 累积含量最高 (分别为 0 14 7%和 0 0 6 1% ) ;接种量为 4g、2g (FW flask) ,有利于人参皂苷Re和人参皂苷Rg1的累积 ;培养基pH 5 8时人参皂苷Re含量最高 (0 184 % ) ,培养基pH 5 6时人参皂苷Rg1 累积量最高 (0 0 5 4 % ) ;肌醇浓度为 0 0 5g L时 ,能促进人参皂苷Re合成 (0 182 % ) ,浓度为 0 30g L时 ,有利于人参皂苷Rg1 累积 (0 0 5 5 % )。     

土生曲霉转化三七中药材的研究

从土壤真菌中筛选出直接转化中药材三七化学成分的菌株YM31966,经鉴定该菌株为土生曲霉(Aspergillus terreus).以固态转化方式,结合化学提取分离方法,通过高效液相色谱、核磁共振及质谱等波谱检测,该菌株转化三七产物由三七皂苷nR2 、RX1和人参皂苷Rg1、Rd、Rh1、Rh4构成主体成分,而原三七成分Rb1、Rc、Re和R1、R3,R6等物质被分解.结果表明,土生曲霉是一株能转化中药材三七的微生物,它具有改变原三七化学成分,形成新化合物,以及提高某些原化合物成分含量的作用.     

黑根霉对人参皂苷Re的生物转化

利用菌种黑根霉Rhizopus sp.对人参皂苷Re进行生物转化,并对人参皂苷Re及其发酵产物进行HPLC系统分析比较,经液相色谱-质谱分析得出人参皂苷Re转化率为92.16%,并制备出人参皂苷Re发酵产物中峰值升高的成分,转化后的人参皂苷发酵产物中化合物1确定为人参皂苷Rg2,化合物2为Rg2的同分异构体,得率为10.13%;化合物3和化合物4确定为人参皂苷Rg5/Rk1,得率为29.23%。从结果初步推测得出人参皂苷Re被黑根霉转化为人参皂苷Rg2的机理,人参皂苷Re转化成人参皂苷Rg5/Rk1的机理还有待于进一步研究。     

外源人参皂苷对人参种子萌发和幼根抗氧化酶活性的影响

研究不同浓度外源人参皂苷(人参总皂苷,人参二醇组皂苷,人参三醇组皂苷, Rb族,Rb3,Re共4种皂苷混合物和两种单体皂苷)对人参种子萌发,幼苗根长、鲜重,幼根中抗氧化酶活性和MDA含量的影响.结果表明:所测试人参皂苷对人参种子萌发、人参幼苗根长生长和幼根鲜重增加均具有抑制化感效应,且抑制程度均随处理浓度的升高而增强;对人参幼根中抗氧化酶活性方面,不同浓度人参总皂苷,人参二醇组皂苷,人参三醇组皂苷处理后,人参根系中SOD,POD和CAT活性均有明显提高,呈现出各酶活性随浓度升高而逐渐增强的效应;人参皂苷Rb族处理后,SOD活性在低中浓度处理时,与对照差别不大,中高浓度处理后低于对照,POD活性在中高浓度处理后显著提高,高浓度处理后活性降幅较大难以恢复到对照水平,CAT活性均低于对照;人参皂苷Rb3处理后,SOD活性均低于对照水平,POD活性在低浓度处理时与对照相当,中高浓度处理后显著低于对照水平,CAT活性逐渐降低,在低中浓度处理时略高于对照,高浓度处理后低于对照水平;人参皂苷Re处理后,SOD和POD活性均显著低于对照.人参幼根中MDA含量均随着处理浓度的增加而升高.     

响应面法优化微波提取绞股蓝愈伤组织中人参皂苷Rb1的工艺研究

以绞股蓝愈伤组织为原料,优化绞股蓝人参皂苷Rb1的微波提取工艺,在单因素试验的基础上,选择液料比、微波功率和微波处理时间为自变量,人参皂苷Rb1为响应值,采用响应曲面法设计、分析研究各自变量及其交互作用对人参皂苷Rb1提取率的影响.利用响应面分析方法,模拟得到二次多项式回归方程的预测模型,并确定人参皂苷Rb1微波辅助提取工艺的最佳条件为：料液比1：20（g/mL）,处理时间6 min,微波功率200 W.在此最佳工艺条件下,人参皂苷Rb1得率为3.95 mg/g.     

Simultaneous Determination and Analysis of Major Ginsenosides in Wild American Ginseng Grown in Tennessee

Ginsenosides are the major constituent that is responsible for the health effects of American ginseng. The ginsenoside profile of wild American ginseng is ultimately the result of germplasm, climate, geography, vegetation species, water, and soil conditions. This is the first report to address the ginsenoside profile of wild American ginseng grown in Tennessee (TN), the third leading state for production of wild American ginseng. In the present study, ten major ginsenosides in wild American ginseng roots grown in TN, including Rb1, Rb2, Rb3, Rc, Rd, Re, Rf, Rg1, Rg2, and Rg3, were determined simultaneously. The chemotypic differences among TN wild ginseng, cultivated American ginseng, and Asian ginseng were assessed based on the widely used markers of ginsenoside profiling, including the top three ginsenosides, ratios of PPD/PPT, Rg1/Rb1, Rg1/Re, and Rb2/Rc. Our findings showed marked variation in ginsenoside profile for TN wild ginseng populations. Nevertheless, TN wild ginseng has significant higher ginsenoside content and more ginsenoside diversity than the cultivated ginseng. The total ginsenoside content in TN wild ginseng, as well as ginsenosides Rg1 and Re, increases with the age of the roots. Marked chemotypic differences between TN wild ginseng and cultivated American ginseng were observed based on the chemotypic markers. Surprisingly, we found that TN wild ginseng is close to Asian ginseng with regard to these characteristics in chemical composition. This study verified an accessible method to scientifically elucidate the difference in chemical constituents to distinguish wild from the cultivated American ginseng. This work is critical for the ecological and biological assessments of wild American ginseng so as to facilitate long‐term sustainability of the wild population.     

Effects of ginsenosides on glycine receptor alpha1 channels expressed in Xenopus oocytes

Ginsenosides, major active ingredients of Panax ginseng, are known to regulate the excitatory ligand-gated ion channel activity. Recent reports showed that ginsenosides attenuate nicotinic acetylcholine and NMDA receptor channel activity. However, it is not known whether ginsenosides also affect the inhibitory ligand-gated ion channel activity. We investigated the effect of ginsenosides on human glycine alpha1 receptor channel activity expressed in Xenopus oocytes using a two-electrode voltage clamp technique. Treatment of ginsenoside Rf enhances glycine-induced inward peak current (IGly) with dose dependent and reversible manner but ginsenoside Rf itself did not elicit membrane currents. The half-stimulatory concentrations (EC50) of ginsenoside Rf was 49.8 +/- 8.9 microM. Glycine receptor antagonist strychnine completely blocked the inward current elicited by glycine plus ginsenoside Rf. Cl- channel blocker 4,4'-disothiocyanostilbene-2,2'-disulfonic acid (DIDS) also blocked the inward current elicited by glycine plus ginsenoside Rf. We also tested the effect of eight individual ginsenosides (i.e., Rb1, Rb2, Rc, Rd, Re, Rg1, Rg2, and Ro) in addition to ginsenoside Rf. We found that five of them significantly enhanced the inward current induced by glycine with the following order of potency: Rb1 > Rb2 > Rg2 > or = Rc > Rf > Rg1 > Re. These results indicate that ginsenosides might regulate gylcine receptor expressed in Xenopus oocytes and this regulation might be one of the pharmacological actions of Panax ginseng.     

Protopanaxadiol 6-hydroxylase and its role in regulating the ginsenoside heterogeneity in Panax notoginseng cells

Various structure-similar plant secondary metabolites like ginseng saponins (ginsenosides) possess different or even totally opposite biological activities. Intentional manipulation of the ginsenoside heterogeneity in cellular biosynthesis is of great interest and significance [Zhong and Yue (2005); Adv Biochem Eng Biotechnol 100:53-88]. In this work, CO-binding spectra of microsomes prepared from the suspended cells of Panax notoginseng showed increases in absorption at 450 nm compared with the control without CO sparging, and protopanaxadiol 6-hydroxylase (P6H), a new enzyme catalyzing the conversion of ginsenoside aglycone protopanaxadiol into protopanaxatriol, was found. P6H was dependent on NADPH and molecular oxygen. The enzymatic reaction was inhibited by carbon monoxide and partially reversible upon illumination with blue light, and sensitive to cytochrome P450 inhibitors. The results supported the contention that P6H was a cytochrome P450-dependent hydroxylase, whose catalytic product was confirmed to be protopanaxatriol by HPLC-MS. Induction of P6H activity by phenobarbital, a cytochrome P450 inducer, was observed. A maximal activity of P6H was obtained with addition of 0.5 mM phenobarbital on day 4 of shake-flask cultivation. The maximum content of protopanaxatriol-type ginsenosides (Rg(1) and Re, Rg group) and the maximum ratio of the content of protopanaxatriol: protopanaxadiol reached 6.88 +/- 0.21 mg g(-1) dry weight and 7.0, respectively, which was about 1.4 and 2.0-fold that of respective controls (without addition of phenobarbital). Oxidative burst was also observed in the cell cultures with addition of phenobarbital. P6H was concluded as a key enzyme in regulating Rg-group ginsenoside biosynthesis in P. notoginseng cells.     

Methyl jasmonate elicitation enhanced synthesis of ginsenoside by cell suspension cultures of Panax ginseng in 5-l balloon type bubble bioreactors

The effects of methyl jasmonate (MJ) elicitation on the cell growth and accumulation of ginsenoside in 5-l bioreactor suspension cultures of Panax ginseng were investigated. Ginsenoside accumulation was enhanced by elicitation by MJ (in the range 50–400 M); however, fresh weight, dry weight and growth ratio of the cells was strongly inhibited by increasing MJ concentration. The highest ginsenoside yield was obtained at 200 M MJ. In the second experiment, 200 M MJ was added on day 15 during the cultivation. The ginsenoside, Rb group, and Rg group ginsenoside content increased 2.9, 3.7, and 1.6 times, respectively, after 8 days of MJ treatment. Rb group gisnsenosides accumulated more than Rg group ginsenosides. Among Rb group ginsenosides, Rb1 content increased significantly by four times but the contents of Rb2, Rc and Rd increased only slightly. Among Rg group ginsenosides, Rg1 and Re showed 2.3-fold and 3.0-fold increments, respectively, whereas there was only a slight increment in Rf group ginsenosides. These results suggest that MJ elicitation is beneficial for ginsenoside production using 5-l bioreactor cell suspension cultures.     

Understory light and root ginsenosides in forest-grown Panax quinquefolius

The objective of this study was to determine the relationship between light levels in the understory of a broadleaf forest and the content of six ginsenosides (Rg(1), Re, Rb(1), Rc, Rb(2,) and Rd) in 1- and 2-year-old American ginseng (Panax quinquefolius L.) roots. Our results revealed that ginsenoside contents in 1- and 2 year-old roots collected in September were significantly related to direct and total light levels, and duration of sunflecks. At this time, the effect of light levels accounted for up to 48 and 62% of the variation in ginsenoside contents of 1- and 2-year-old American ginseng roots. Also, red (R) and far red (FR) light, and the R:FR ratio significantly affected Rd, Rc, and Rg(1) contents in 2-year-old roots, accounting for up to 40% of the variation in ginsenoside contents.     

Transformation of Ginsenosides Rb1 and Re from <Emphasis Type="Italic">Panax ginseng</Emphasis> by Food Microorganisms

Ginsenosides Rb1 and Re, respectively belonging to the major protopanaxadiol and protopanaxatriol ginsenosides, were transformed using cell-free extracts from food microorganisms. Rb1 was transformed into compound K via Rd and F2 by Bifidobacterium sp. Int57, Bif. sp. SJ32, Aspergillus niger and A.␣usamii. Lactobacillus delbrueckii, and Leuconostoc paramesenteroides transformed Rb1 into Rh2 via Rd and F2. Bifidobacterium sp. SH5 transformed Rb1 into F2 via Rd. Re was transformed into Rh1 via Rg2 by Bif. sp. Int57 and Bif. sp. SJ32. A. niger transformed Re into Rh1 via Rg1. A. usamii transformed Re into Rg2. Transformation of Rb1 proceeded at a higher rate and needed less amount of enzymes than that of Re. Taken together, these processes would allow a specific bioconversion process possible to obtain specific ginsenosides using an appropriate combination of ginsenoside substrates and specific microbial enzymes.     

Neuroprotective effect of individual ginsenosides on astrocytes primary culture

Most of the known pharmacological effects of Panax ginseng on the central nervous system are due to its major components - ginsenosides. Although the antioxidant ability of ginseng root has already been established, this activity has never been evaluated for isolated ginsenosides on astrocytes. The activity of protopanaxadiols Rb(1), Rb(2), Rc and Rd, and protopanaxatriols Re and Rg(1) was evaluated in vitro on astrocytes primary culture by means of an oxidative stress model with H(2)O(2). The viability of astrocytes was determined by the MTT reduction assay and by the LDH release into the incubation medium. The effects on the antioxidant enzymes catalase, superoxide dismutase (SOD), glutathione peroxidases (GPx) and glutathione reductase (GR) and on the intracellular reactive oxygen species (ROS) formation were also investigated. Exposure of astrocytes to H(2)O(2) decreased cell viability as well as the antioxidant enzymes activity and increased ROS formation. Oxidative stress produced significant cell death that was reduced by previous treatment with the tested ginsenosides. Ginsenosides Rb(1), Rb(2), Re and Rg(1) were effective in reducing astrocytic death, while Rb(1), Rb(2), Rd, Re and Rg(1) decreased ROS formation, ginsenoside Re being the most active. Ginsenosides from P. ginseng induce neuroprotection mainly through activation of antioxidant enzymes.