Enhancing plant uptake of polychlorinated biphenyls and cadmium using tea saponin

The potential of natural surfactant tea saponin to enhance uptake of polychlorinated biphenyls (PCBs) and cadmium (Cd) by Zea Mays L. and Saccharum officinarum L. was investigated. With addition of tea saponin at 0.01% in solution culture, the concentrations of PCB 14, PCB 18, PCB 77 and PCB 156 in root of corn seedling were 2.72, 2.68, 1.94 and 2.40 times as those of treatments without adding any surfactant, respectively. Application of tea saponin to the soil significantly elevated PCB 5 accumulation in shoots and roots (p < 0.05) by sugarcanes. With addition of 0.3% tea saponin, Cd concentration was increased by 96.9% in roots, 156.8% in stems and 30.1% in leaves compared with the treatment without addition of surfactant in sugarcane grown in soil. Tea saponin had potential of assisting the uptake of PCBs and Cd by plants from water solution and soil.     

蒺藜皂苷对动脉粥样硬化大鼠动脉壁ICAM-1、VCAM-1、PPARα、PPARγ基因表达的影响

观察全草蒺藜皂苷（tribu saponin from Tribulus terrestris,STT）对实验性动脉粥样硬化（atherosclerosis,AS）大鼠动脉壁中ICAM-1、VCAM-1、PPARα和PPARγ基因表达的影响,以探讨STT抗AS的机制。应用高脂饲料饮食配合注射维生素D,建立SD大鼠AS模型,并设立正常组、模型组、辛伐他汀组和蒺藜皂苷低、中、高剂量组。采用半定量RT-PCR的方法检测各组动物动脉壁中ICAM-1、VCAM-1、PPARα和PPARγ基因的表达,分析造模及各给药大鼠ICAM-1、VCAM-1、PPARα和PPARγ基因表达的变化。与正常组相比,模型组ICAM-1和VCAM-1基因的表达量明显增加（P〈0．01）,而PPARα和PPARγ基因的表达量明显降低（P〈0．01）;与模型组相比,辛伐他汀及各STT药均能降低ICAM-1和VCAM-1基因的表达量（P〈0．01～P〈0．05）,并能增加PPARα和PPARγ基因的表达量（P〈0．01）。提示STT能下调实验性AS大鼠动脉壁ICAM-1和VCAM-1基因的表达及上调PPARα和PPARγ基因表达,这可能是STT抗AS的作用机制之一。     

盾叶薯蓣总皂苷超声提取及动力学

考察了乙醇体积分数、溶剂用量、超声时间、超声功率和超声频率对盾叶薯蓣总皂苷提取率的影响,研究了以体积分数70%乙醇溶液或水作溶剂从盾叶薯蓣中超声提取总皂苷的动力学模型。结果表明,在扩散过程中超声提取薯蓣总皂苷的动力学模型满足非定常扩散方程,相关系数为r=0.95,最佳超声时间为40min。     

Identification and differentiation of Panax species using ELISA, RAPD and eastern blotting

Immunochemical and genetic methods have been developed in order to distinguish Panax spp. With the aim of establishing immunochemical methods, two hybridomas (3H4 and 5H8), each secreting a monoclonal antibody (MAb) against proteins of Panax ginseng, were prepared by fusing splenocytes immunized with two kinds of ginseng water-soluble fractions and a hypoxanthine-thymidine-aminopterin-sensitive mouse myeloma cell line, P3-X63-Ag8-U1. MAb 3H4 cross-reacted with four Panax spp., whereas the MAb 5H8 cross-reacted with P. ginseng in the enzyme-linked immunosorbent assay (ELISA). ELISA and western blotting methods using a ginseng water-soluble fraction as the solid-phase antigen were developed for the unambiguous authentication of P. ginseng. A combination of random amplified polymorphic DNA (RAPD) and eastern blotting analyses using anti-ginsenoside Rb1 and Rgl monoclonal antibodies was used for the identification of P. notoginseng, P. quinquefolius and P. japonicus. RAPD can be used to differentiate the species of Panax from each other. An important parameter used for differentiating P. notoginseng is the absence of ginsenoside Rc in the extract of P. notoginseng with eastern blotting. The combination of these methods enabled a reliable identification of Panax spp.     

The influence of lead and arsenite on the inhibition of human breast cancer MCF-7 cell proliferation by American ginseng root (Panax quinquefolius L.)

American ginseng root (Panax quinquefolius) has a number of purported therapeutic effects, including inhibition of cancer cell proliferation. The ability of environmentally relevant heavy metals to alter ginseng effects on cancer cell growth was the subject of this study. A water extract of American ginseng root was applied alone or in combination with physiologically relevant doses of either lead (Pb) or arsenite to MCF-7 breast cancer cells in vitro and effects on cell proliferation were determined. Ginseng alone produced a significant dose-dependent inhibition of MCF-7 cell proliferation starting at 0.5 mg ml(-1). Treatment of MCF-7 cells with 2.5 microM arsenite significantly decreased MCF-7 cell proliferation (p < 0.01). When cells were treated with arsenite (1.25 or 2.5 microM) in combination with ginseng extract (0.5 mg ml(-1)), there was an apparent synergistic inhibition of cell proliferation. Treatment of MCF-7 breast cancer cells with 50 microM Pb significantly decreased cell proliferation relative to control (p < 0.01), and concomitant ginseng and Pb treatment did not lead to a further decrease. These results suggest that contaminant heavy metals, some of which have been detected in ginseng root extracts or commercial ginseng preparations, may alter the biological activity of ginseng.     

Characterization of UDP-glucose dehydrogenase isoforms in the medicinal legume Glycyrrhiza uralensis

Uridine 5′-diphosphate (UDP)-glucose dehydrogenase (UGD) produces UDP-glucuronic acid from UDP-glucose as a precursor of plant cell wall polysaccharides. UDP-glucuronic acid is also a sugar donor for the glycosylation of various plant specialized metabolites. Nevertheless, the roles of UGDs in plant specialized metabolism remain poorly understood. Glycyrrhiza species (licorice), which are medicinal legumes, biosynthesize triterpenoid saponins, soyasaponins and glycyrrhizin, commonly glucuronosylated at the C-3 position of the triterpenoid scaffold. Often, several different UGD isoforms are present in plants. To gain insight into potential functional differences among UGD isoforms in triterpenoid saponin biosynthesis in relation to cell wall component biosynthesis, we identified and characterized Glycyrrhiza uralensis UGDs (GuUGDs), which were discovered to comprise five isoforms, four of which (GuUGD1–4) showed UGD activity in vitro. GuUGD1–4 had different biochemical properties, including their affinity for UDP-glucose, catalytic constant, and sensitivity to feedback inhibitors. GuUGD2 had the highest catalytic constant and highest gene expression level among the GuUGDs, suggesting that it is the major isoform contributing to the transition from UDP-glucose to UDP-glucuronic acid in planta. To evaluate the contribution of GuUGD isoforms to saponin biosynthesis, we compared the expression patterns of GuUGDs with those of saponin biosynthetic genes in methyl jasmonate (MeJA)-treated cultured stolons. GuUGD1–4 showed delayed responses to MeJA compared to those of saponin biosynthetic genes, suggesting that MeJA-responsive expression of GuUGDs compensates for the decreased UDP-glucuronic acid pool due to consumption during saponin biosynthesis.     

4种人参属植物基因组大小的测定

人参属（Panax）植物是重要的药用植物资源。以水稻（Oryzasativa）为内标,利用流式细胞术测定了三七（Panaxnotoginseng）、屏边三七（Panaxstipuleanatus）、越南三七（Panaxvietnamensis）及假人参（几n似pse“doginseng）4种人参属植物的基因组大小。结果表明,4种植物的基因组大小各不相同,其中。三七的最大,而屏边三七的最小。本组数据将为该属植物的基因组学研究以及种群进化研究提供基础数据参考。     

三七自毒与化感作用初步研究

采用生物测定方法,对三七的自毒与化感作用进行初步研究。结果表明:(1)三七种子萌发过程中的自毒作用随其播种密度不同而有一定差异,但无明显规律性。三七种子萌发过程中的分泌物对油菜生长具有化感作用,主要表现为对油菜种子发芽率、发芽指数及苗高的抑制效应;(2)三七水浸液对不同受体植物的化感作用不尽相同,对小麦主要表现为对苗鲜重、苗干重、根鲜重、苗高及须根数有不同程度的促进或抑制作用;对油菜则表现为对其种子发芽率具有抑制作用,而对苗鲜重、苗干重、根鲜重、最长根长具有促进作用;(3)三七存在明显的化感自毒作用,其自毒物质可能为影响其连作的一个重要因素。     

无患子水提皂素液发酵精制联产生物表面活性剂槐糖脂

无患子水提皂素液,经纤维二糖酶水解,以无患子水提水解液为底物,接种丘陵假丝酵母,将水提液中糖组分发酵转化为槐糖脂,得到天然皂素及生物表面活性剂复合产物。在发酵过程中,2%的丘陵假丝酵母菌种接种量,溶液中葡萄糖消耗速率最快;在水提水解液中额外添加大豆油作为补充碳源能较大幅度降低溶液表面张力。经过发酵转化,溶液中表面活性物质浓度达到52.48 g/L,比发酵前提高了23.4%,溶液表面张力值明显降低。无患子精制发酵液中不含糖类成分,是理想的液体洗涤剂生产原料。     

超声波法提取剑花总皂苷工艺研究

利用超声波法,采用正交实验对剑花总皂苷提取工艺进行研究。结果表明,提取剑花总皂苷的最优条件为:粒度80目,最佳溶剂水,超声时间40 min,溶剂挥干温度80℃,料液比1:20。