蒲公英研究进展和用生物技术培育耐盐蒲公英展望

蒲公英属（Taraxacum）植物种类多,分布广,是常见的农业杂草,还是重要的中药材。目前,蒲公英作为蔬菜食用得到了人们的充分重视,并逐渐成为时尚。近年来,人们深入研究了蒲公英的化学成分和药理作用,关于蒲公英的组织培养、核型与分子水平的研究也已开展,但蒲公英的生物技术培育工作鲜有报道。在对蒲公英的开发利用和研究现状作概述的同时,结合我们的工作提出生物技术培育抗盐、耐海水蒲公英的努力方向,以期为进一步开发利用蒲公英打下基础。     

野生植物蒲公英营养成分的研究

对野生植物蒲公英的营养成分进行了分析,结果表明,蒲公英中含有多种营养成分,丰富的矿质元素和维生素及其β-胡萝卜素。蒲公英中至少含有17种氨基酸。蒲公英营养成分分析旨在为开发利用植物资源提供科学依据。     

蒲公英的食用与载培

本文介绍了蒲公英的营养成分,保健品开发及载培技术要点等方面的情况,供开发利用蒲公英资源参考。     

蒲公英的经济价值及其开发利用

蒲公英 ( Tayaxacum mougo)　又名黄花地丁 ,黄花苗 ,黄花三七等。为菊科多年生草本植物。《唐本草》和《本草纲目》均称为黄花地丁。几千年来 ,蒲公英一直是人们普遍食用的时令野菜 ,现今随着对其开发利用价值的深入研究 ,特别是医疗、保健功能的发现 ,已广泛引起医学专家和营养专家的重视 ,一批医药和保健产品相继投放市场 ,加之传统中药上的应用 ,蒲公英极大的经济价值正得到体现。1　蒲公英的形态特征和生物学特性蒲公英属直根系 ,根垂直生长 ,入土深度达 1～3 m。幼苗期匍匐于地面。叶根生、无柄、簇生、排成莲状平铺 ,绿色或边缘有淡…     

蒲公英黄酮类物质提取条件的优化与含量测定

蒲公英是一种常见的药用植物,内含多种化学物质,研究蒲公英内含的化学成分对其药用价值的开发利用具有重要意义。以蒲公英全草为研究对象,采用超声辅助溶剂提取法提取其黄酮类物质,对提取时间和提取温度进行优化,确定最佳提取条件;采用分光光度法,以芦丁标准溶液为标样,测定蒲公英内黄酮类物质的含量。结果表明,提取温度为70℃、提取时间为30min时,蒲公英黄酮类物质的提取效果最佳;蒲公英中黄酮类物质含量为4.33%。     

野生蒲公英与栽培蒲公英的比较研究

在本实验通过显微鉴别 (切片、粉未 )、理化鉴别及薄层层析等方法对野生蒲公英和载培蒲公英进行比较研究 ,结果野生蒲公英和栽培蒲公英在组织结构上有明显区别 ,但在化学成份上没有区别 ,因此可以用载培蒲公英替代野生蒲公英以扩大药源     

蒲公英小拱棚栽培

蒲公英小拱棚栽培吴会昌,曾宪宏,杨志兴（辽宁铁岭农校园艺科１１２００１）蒲公英为春季主要野菜,全株可食,营养丰富,且有清热解毒、利尿散结之功效,越来越受到人们的欢迎。用小拱棚栽培蒲公英,不仅实现了蒲公英的早熟,丰富了居民的菜篮子,而且产品鲜嫩,经济效...     

药食佳品—蒲公英

随着人们对健康的日益关注 ,越来越重视天然无污染的野生植物资源 ,蒲公英既是常用的中药材 ,又是一种天然营养型保健型绿色食品 ,已逐渐进入餐桌 ,倍受人们的青睐。近年来 ,日本、法国、美国和我国已陆续兴起了“蒲公英”热。蒲公英 (ＴａｒａｘａｃｕｍｍｏｎｇｏｌｉｃｕｍＨａｎｄ .-Ｍａｚｚ .)为菊科蒲公英属多年生草本植物 ,别名黄花地丁、婆婆草 (丁 )、奶汁草、黄花三七、蒲公草等 ,全株含白色乳汁 ,根直生 ,肥厚 ,圆锥形 ;叶莲座状丛生 ,倒披针形 ,大头羽浅或深裂 ,全缘或有数齿 ,基部渐狭成柄 ,不同生长期 ,不同环境中叶形变化较…     

新疆蒲公英属一新种

本文报道了新疆产蒲公英属植物一新种——新源蒲公英Taraxacum xinyuanicum D．T．Zhai et Z. X．An,并对其模式产地种群中其它个体的形态变异做了进一步的说明,同时还指出它与药用蒲公英 T.officinale Wigg．和堆叶蒲公英T．compactum Schischk 的异同;花粉体积变异、败育率和染色体数目的统计表明它是一个二倍体,与后面的两个多倍体种有明显的差别。     

苦口良药—蒲公英

蒲公英为菊科植物蒲公英Ｔａｒａｘａｃｕｍｍｏｎ ｇｏｌｉｃｕｍＨａｎｄ .-Ｍａｚｚ、碱地蒲公英ＴａｒａｘａｃｕｍｓｉｎｉｃｕｍＫｉｔａｇ ,或同属植物异胞蒲公英、热河蒲公英、西藏蒲公英的带根全草。又名婆婆丁、黄花地丁草等。多生长于山坡草地、路旁及田野间。全国大部分地区均有分布。药材特征 :本品呈皱缩卷曲的团块。根呈圆锥状 ,多弯曲 ,长 3～ 7ｃｍ ;表面棕褐色 ,抽皱 ;根头部有棕褐色或黄白色的茸毛 ,有的已脱落。叶基生 ,多皱缩破碎 ,完整叶片呈倒披针形 ,绿褐色或暗灰色 ,先端尖或钝 ,边缘浅裂或羽状分裂 ,基部渐狭 ,下…     

<Emphasis Type="Italic">Agrobacterium tumefaciens</Emphasis>-mediated transformation of a medicinal plant <Emphasis Type="Italic">Taraxacum platycarpum</Emphasis>

Dandelion plants, the genus Taraxacum, are used in herbal medicine owing to their choleretic, diuretic and anti-carcinogenic activities and several medicinal compounds have been isolated from the roots of these plants. Metabolic manipulation of secondary metabolite biosynthesis is a potential strategy to improve the production of high-value secondary metabolites. The enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) is known to control a key regulatory step in the isoprenoid pathway. We report an efficient transformation protocol for stable introduction of HMGR into dandelion plants (Taraxacum platycarpum H. Dablstaed), which is essential for the biotechnological approach. The Agrobacterium tumefaciens strain EHA105 containing the binary vector, pCAMBIA1301, with GUS and HMGR genes, showed high transformation efficiency after 3–5 week hygromycin selection. Southern blotting, GUS staining and RT-PCR analyses demonstrated stable integration of one copy of the HMGR gene into the dandelion genome. Expression of the integrated genes was particularly eminent in root tissues of primary transformant plants. The establishment of an efficient transformation method may facilitate the improvement of medicinal plant in terms of the accumulation levels of secondary metabolites.     

Current biotechnological applications of the genus Amycolatopsis

Recently there has been increasing interest in possible biotechnological applications of the bacterial genus Amycolatopsis. This genus originally attracted attention for its antibiotic producing capabilities; although it is actually a multifaceted genus and a more diverse range of studies involving biotechnological processes have now been undertaken. Several works have demonstrated that the versatility shown by these bacteria is valuable in industrial applications. Here, we provide a condensed overview of the most important biotechnological applications such as bioremediation, biodegradation and bioconversion, as well as aspects that need to be explored further in order to gain a fuller insight into this genus, including its possible potential in the production of biofuel. Antibiotic production is not discussed since this is well covered by the latest edition of Bergey’s Manual of Systematic Bacteriology. To our knowledge this is the first report highlighting the versatility and biotechnological potential of the genus Amycolatopsis.     

Der Laborkleinfermentor LF2 – Physikalische Kenndaten,Beurteilung der Originalkonfiguration und Charakterisierung spezieller Ausrüstungsvarianten

The stirred laboratory scale fermenter LF2 is a powerful device for fermentations with up to 3 liters culture broth [1]. It was designed in the Academy of Sciences of the C.S.S.R. and has found a rather wide application in a great number of organizations working in the fields of biotechnological education, research and industry in the G.D.R. and the C.S.S.R. The LF2-fermenter is well suitable for carrying out a broad manifold of aerated biotechnological works without contaminations in basic research and process development. The mechanic and electronic design gives a lot of room for the realization of special equipment variants like special-shaped reactor vessels or special electronic moduls for automatic control.     

香蕉生物技术研究进展

近50年来香蕉的生产得到了稳步的发展,同时正遭受越来越严重的病虫、霜冻和台风的侵害。鲜食蕉雌雄性高度不育的特性,使得传统的育种方法难以进行香蕉的遗传改良。这些现状迫切要求香蕉生物技术的不断发展和深入。近10年来,在香蕉体细胞胚胎发生、原生质体培养、基因克隆和序列分析以及基因转化等方面都取得了可喜的成果,并预计于2006年完成香蕉基因组的测序 。     

Metabolic reconstruction and flux analysis of industrial Pichia yeasts

Pichia yeasts have been recognized as important microbial cell factories in the biotechnological industry. Notably, the Pichia pastoris and Pichia stipitis species have attracted much research interest due to their unique cellular physiology and metabolic capability: P. pastoris has the ability to utilize methanol for cell growth and recombinant protein production, while P. stipitis is capable of assimilating xylose to produce ethanol under oxygen-limited conditions. To harness these characteristics for biotechnological applications, it is highly required to characterize their metabolic behavior. Recently, following the genome sequencing of these two Pichia species, genome-scale metabolic networks have been reconstructed to model the yeasts’ metabolism from a systems perspective. To date, there are three genome-scale models available for each of P. pastoris and P. stipitis. In this mini-review, we provide an overview of the models, discuss certain limitations of previous studies, and propose potential future works that can be conducted to better understand and engineer Pichia yeasts for industrial applications.     

Foam fractionation applications

Biotechnological downstream processing faces several challenges, such as dilute product streams and contained target products which are sensitive to heat, oxidation, other chemicals, etc. State-of-the-art separation methods, e.g. chromatography, are not always the best option due to variable yield losses and high costs. Foam fractionation appears as a promising alternative unit operation in biotechnological downstream processing. From its applications in metal industry and on fish farms, it was developed further towards the recovery of phytonutrients, metabolites and proteins. However, no large scale applications of foam fractionation in biotechnological downstream processing exist yet. This is due to the complexity of various biotechnological media, which makes a universalized approach for systematic process design of protein separations difficult. Ongoing research in the fields of process engineering, surface chemistry and protein chemistry can help to close this gap. Although many different substances, such as detergents, have been separated or recovered using foam fractionation, this review focuses mainly on biotechnological applications, more specifically on protein separation.     

Altered levels of the Taraxacum kok-saghyz (Russian dandelion) small rubber particle protein,TkSRPP3, result in qualitative and quantitative changes in rubber metabolism

Several proteins have been identified and implicated in natural rubber biosynthesis, one of which, the small rubber particle protein (SRPP), was originally identified in Hevea brasiliensis as an abundant protein associated with cytosolic vesicles known as rubber particles. While previous in vitro studies suggest that SRPP plays a role in rubber biosynthesis, in vivo evidence is lacking to support this hypothesis. To address this issue, a transgene approach was taken in Taraxacum kok-saghyz (Russian dandelion or Tk) to determine if altered SRPP levels would influence rubber biosynthesis. Three dandelion SRPPs were found to be highly abundant on dandelion rubber particles. The most abundant particle associated SRPP, TkSRPP3, showed temporal and spatial patterns of expression consistent with patterns of natural rubber accumulation in dandelion. To confirm its role in rubber biosynthesis, TkSRPP3 expression was altered in Russian dandelion using over-expression and RNAi methods. While TkSRPP3 over-expressing lines had slightly higher levels of rubber in their roots, relative to the control, TkSRPP3 RNAi lines showed significant decreases in root rubber content and produced dramatically lower molecular weight rubber than the control line. Not only do results here provide in vivo evidence of TkSRPP proteins affecting the amount of rubber in dandelion root, but they also suggest a function in regulating the molecular weight of the cis-1, 4-polyisoprene polymer.     

蒲公英抗肿瘤活性部位的GC-MS分析研究

目的：考察蒲公英提取物对MCF-7增殖作用的影响,研究蒲公英抗肿瘤活性部位的化学成分。方法：采用MTT法比较蒲公英水提物、醇提物和不同极性提取物对MCF-7增殖的影响;以气相色谱．质谱（GC-MS）联用技术对具有抑制MCF-7人乳腺癌细胞增殖的部位进行分离和鉴定。结果：蒲公英水提物和醇提物对MCF-7细胞均有抑制作用,体外最大抑制率分别达到92．95％、93．59％,蒲公英不同极性溶剂提取物中,氯仿部位抑制MCF-7的增殖,且抑制作用高于醇提和水提物,乙酸乙酯和石油醚部位促进MCF-7的增殖。从蒲公英氯仿提取物中鉴定出80种化合物,占其总量的98．07％。结论：蒲公英氯仿部位具有抗肿瘤活性,为蒲公英抗肿瘤活性成分的研究提供了依据,拓展了筛选中药活性成分的方法。     

Dandelion Seed Dispersal: The Horizontal Wind Speed Does Not Matter for Long-Distance Dispersal - it is Updraft!

Abstract: Long-distance dispersal of seeds (LDD) surely affects most ecological and evolutionary processes related to plant species. Hence, numerous attempts to quantify LDD have been made and, especially for wind dispersal, several simulation models have been developed. However, the mechanisms promoting LDD by wind still remain ambiguous and the effects of different weather conditions on LDD, although recognized as important, have only rarely been investigated. Here we examine the influence of wind speed and updrafts on dispersal of dandelion ( Taraxacum officinale agg.), a typical wind-dispersed herb of open habitats. We used PAPPUS, a weather-sensitive mechanistic simulation model of wind dispersal, which considers frequency distribution of weather conditions during the period the simulation refers to. A simulation for the 4-month shedding period of dandelion shows that high wind speed does not promote LDD. In contrast, vertical turbulence, especially convective updrafts, are of overwhelming importance. Mainly caused by updrafts, in the simulations more than 0.05 % of dandelion seeds were dispersed beyond 100 m, a distance commonly used to define LDD. We conclude that long-distance dispersal of seeds of herbaceous species with falling velocities < 0.5 - 1.0 ms^-1 is mainly caused by convective updrafts.