影响蓝色花着色的因素

在观赏植物中,花卉的蓝色品系非常罕见,尤其是那些名贵花卉,如月季、百合、郁金香、香石竹。菊花等均缺乏蓝色的品种,因此,培育这些品种的蓝色品系一直是花卉育种学家的主攻目标。通过对蓝色花化学成分、花色素苷生物合成途径以及液泡pH值的广泛研究,人们已经了解到蓝色花的显现与花瓣液泡中的色素成分、助色素(copig-ments)、金属阳离子、液泡的pH值密切相关。本文介绍和讨论这些影响蓝色花显现的因素,以期为培育蓝色花提供参考资料。     

巧用牵牛花观察酸碱度对花青素颜色的影响

花青素存在于植物细胞的液泡中,花瓣、果实和叶片上的颜色．除绿色外,基本上是花青素显示的颜色。花青素的颜色会随液泡内酸碱度的变化而变化,液泡为酸性时呈红色,碱性时呈蓝色。经过实践我们认为,观察这一现象用旋花科的牵牛花(俗名喇叭花)效果很好,材料也容易得到。     

蓝色玫瑰研究进展

蓝色玫瑰是长期困扰各国花卉育种学家的花卉品系之一。对近年来影响蓝色花形成的因素,如细胞中的花素苷成分、助色素、液泡pH值等因素的研究进行综述,提出了通过基因工程培育蓝色玫瑰的可能途径和需要解决的主要问题。     

蓝色花形成分子机理研究进展

花色是观赏植物的重要特征, 在自然界中蓝色花占比很少, 很多观赏植物都缺少蓝色种质。因此, 研究蓝色花形成的分子机理对于蓝色花定向育种具有重要意义。研究表明, 花色的形成主要是通过花青苷积累, 花青素通过糖基化形成花青苷, 再通过酰基、甲基化修饰及金属离子络合反应, 在特定的液泡pH环境中呈现出稳定的蓝色。该文从花青苷合成与代谢途径入手, 对蓝色花形成关键基因功能、花青苷各位点酰化的影响、金属离子的作用、液泡pH值相关基因研究及蓝色花分子育种等方面进行综述。     

基于花青素代谢培育蓝色花卉的研究进展

花色是植物吸引昆虫传播花粉的主要因素,对于植物在自然界的生存必不可少,也是观赏植物最重要的性状之一。在蓬勃发展的花卉产业中,色彩各异花卉的培育,可以弥补自然花色的匮乏,但是令人垂涎的蓝色花比较难培育。花色的多样性主要是由花青素及其衍生物的种类和含量等因素决定的,飞燕草色素的合成是形成蓝色花的关键因素,许多植物体内缺少合成飞燕草色素的结构基因。近年来,利用基因工程技术培育蓝色花的研究也时有报道。文中以常见的观赏植物为例,基于花青素代谢调控,从影响飞燕草色素合成的关键因素和不同分子改良途径培育蓝色花等几个方面对植物花朵呈色的机制进行了综述,并展示不同分子育种策略可能在其他领域的应用,为其他植物或经济作物的色泽改良如彩色棉蓝色纤维的培育等提供参考和技术支持。     

蓝色花形成分子机理研究进展

花色是观赏植物的重要特征,在自然界中蓝色花占比很少,很多观赏植物都缺少蓝色种质。因此,研究蓝色花形成的分子机理对于蓝色花定向育种具有重要意义。研究表明,花色的形成主要是通过花青苷积累,花青素通过糖基化形成花青苷,再通过酰基、甲基化修饰及金属离子络合反应,在特定的液泡pH环境中呈现出稳定的蓝色。该文从花青苷合成与代谢途径入手,对蓝色花形成关键基因功能、花青苷各位点酰化的影响、金属离子的作用、液泡pH值相关基因研究及蓝色花分子育种等方面进行综述。     

蓝色花形成的基因工程进展与育种策略

蓝色花观赏价值高,花色成因复杂。目前,在蓝色花色形成机理和基因工程育种研究方面取得了大量的研究进展。综述了蓝色花形成的化学、生理学和分子生物学机理,利用基因工程技术培育蓝色花的育种实践:包括转入花青素苷合成途径上的关键酶基因,抑制内源竞争酶基因,转入液泡pH值调节基因和金属离子转运蛋白基因等。在此基础上总结出几种蓝色花基因工程育种的基本策略,以期为蓝色花基因工程育种提供参考。     

问题解答

问:花瓣为什么会显出不同的颜色? 答:花瓣所表现出来的五颜六色,实质上是细胞内各种色素存在的反映。这些包括花青素和类胡萝卜素。前者存在于液泡中,由于细胞液pH的变化,花青素会出现红、紫、蓝等不同的颜色。如将红色的牵牛花浸在碱水中,就会变成蓝色;再浸入酸水中又会重新变红;如用清水冲洗多次又会变成紫色。这就证明红、紫和蓝色的花青紊在不同pH条件下的不同反映(它相当于一种pH指示剂)。     

植物花青素苷转运机制的研究进展

花青素苷的合成过程是生物学上研究得较为清楚的代谢通路之一,但其最后阶段的分子机制即花青素苷从细胞质被转运至中央液泡的过程却仍不清晰。最近研究者们刚刚开始对类黄酮化合物的转运过程进行动态的描绘,迄今共提出了4种花青素苷转运模型,发现了4类与花青素苷转运过程相关的转运蛋白:谷胱甘肽转移酶、多药耐药抗性相关蛋白、多药和有毒化合物排出家族和同源于哺乳动物的胆红素易位酶同族体,并对这4种转运体及相关基因的功能进行了初步研究。尽管已经提出了不同的花青素苷转运模型,但仍然缺乏对不同物种不同类型花青素苷向液泡转运及在液泡中沉积的细胞学和亚细胞学研究。根据获得的信息,可以通过开展基因序列分析、基因表达分析、亚细胞定位和互补试验等,探求转运蛋白的功能及其作用位置,更好地解析植物体内花青素苷的转运机制。     

《植物杂志》:研究发现一种蛋白质可增加花青素含量

<正>花朵的缤纷色彩、果实的艳丽颜色,主要是由花青素决定的。日本研究人员日前对牵牛花进行研究后发现,有一种蛋白质能够增加花青素含量。这一发现有望促进开发出更加艳丽的花卉和水果品种。花青素属于水溶性色素,是构成花瓣和果实颜色的主要色素之一,含量越高颜色越鲜艳。牵牛花中的花青素可使其呈现深紫色或者深蓝色。不过,牵牛花非常容易发生突然变异,导致花青素减少,所开花朵的颜色变淡。日本自然科学研究机构基础生物学研究所的研究人员在新一期英国《植物杂志》上报告说,他们将花色很淡的牵牛花基因与花色很深的牵牛     

Anthocyanins from Pomegranate (Punica granatum L.) and Their Role in Antioxidant Capacities in Vitro

As phytochemicals, anthocyanins are not only responsible for the diverse colors in nature, but are associated with broad-spectrum health-promoting effects for human beings. Pomegranate is abundant in anthocyanins which possess high antioxidant capacities. However, the pomegranate anthocyanins profile and their contributions to antioxidant capacities are not fully depicted. The purpose of this article is to review anthocyanins from pomegranate as important antioxidants. Total anthocyanin content (TAC) and six major components vary greatly with intrinsic and extrinsic factors. In pomegranate, anthocyanins mainly acted as primary antioxidants, while their action as secondary antioxidants were not conclusive. The antioxidant potentials of anthocyanins were significantly affected by factors especially chemical structure and detection assays in vitro. The current knowledge may provide insights into potential applications for pomegranate anthocyanins based on their antioxidant activities.     

茄科蔬菜花青素苷分子调控研究进展

花青素苷是一种分布广泛的水溶性色素,不仅赋予了果实多彩的外表,还是天然食用色素的重要来源。近年来有关茄科蔬菜花青素苷的研究逐渐增多,文中从花青素苷结构及其生物合成途径、茄科蔬菜中花青素苷合成代谢的结构基因和调节基因、影响合成的环境因素等方面进行回顾和总结,为进一步阐明茄科蔬菜花青素苷的合成及调控机理、更好利用花青素苷进行果色品质育种的创新提供一些参考。     

The stabilizing effect of the acyl group on the co-pigmentation of acylated anthocyanins with C-glucosylflavones

The stability of the complex formed between acylated anthocyanins and flavocommelin was compared with that between unacylated anthocyanins and the flavone. At low anthocyanin concentrations (5 × 10^?4 M), the complex involving acylated anthocyanins was much stabler than that involving ordinary anthocyanins. This extra stability is due to the acyl moiety in the acylated anthocyanins. The co-pigmentation constant (Kc) is defined as the affinity between an anthocyanin and its co-pigment.     

Urinary excretion of anthocyanins in humans after cranberry juice ingestion

Cranberry, which is rich in polyphenols, including anthocyanins and proanthocyanidins, has been found to have various effects beneficial to human health, including prevention of urinary tract infections. These effects have been associated with polyphenols in the fruit. We investigated the excretion of anthocyanins in human urine after ingestion of cranberry juice. Eleven healthy volunteers consumed 200 ml of cranberry juice containing 650.8 microg total anthocyanins. Urine samples were collected within 24 h before and after consumption. Six of 12 anthocyanins identified in cranberry were quantified in human urine by HPLC coupled with electrospray ionization and tandem mass spectrometry (HPLC-ESI-MS-MS). Among these, peonidin 3-O-galactoside, the second most plentiful anthocyanin in the juice, was found most abundantly in urine within 24 h, corresponding to 41.5 nmol (56.1% of total anthocyanins). The urinary levels of anthocyanins reached a maximum between 3 and 6 h after ingestion, and the recovery of total anthocyanins in the urine over 24 h was estimated to be 5.0% of the amount consumed. This study found high absorption and excretion of cranberry anthocyanins in human urine.     

Diversity in plant red pigments: anthocyanins and betacyanins

Plant pigments are of interest for research into questions of basic biology as well as for purposes of applied biology. Red colors in flowers are mainly produced by two types of pigments: anthocyanins and betacyanins. Though anthocyanins are broadly distributed among plants, betacyanins have replaced anthocyanins in the Caryophyllales. Red plant pigments are good indicator metabolites for evolutionary studies of plant diversity as well as for metabolic studies of plant cell growth and differentiation. In this review, we focus on the biosynthesis of anthocyanins and betacyanins and the possible mechanisms underlying the mutual exclusion of betalains and anthocyanins based on the regulation of the biosynthesis of these red pigments.     

Anthocyanidin synthase in non-anthocyanin-producing Caryophyllales species

Red colors in flowers are mainly produced by two types of pigments: anthocyanins and betacyanins. Although anthocyanins are widely distributed in higher plants, betacyanins have replaced anthocyanins in the Caryophyllales. There has been no report so far to find anthocyanins and betacyanins existing together within the same plant. This curious phenomenon has been examined from genetic and evolutionary perspectives, however nothing is known at the molecular level about the mutual exclusion of anthocyanins and betacyanins in higher plants. Here, we show that spinach (Spinacia oleracea) and pokeweed (Phytolacca americana), which are both members of the Caryophyllales, have functional anthocyanidin synthases (ANSs). The ability of ANSs of the Caryophyllales to oxidize trans-leucocyanidin to cyanidin is comparable to that of ANSs in anthocyanin-producing plants. Expression profiles reveal that, in spinach, dihydroflavonol 4-reductase (DFR) and ANS are not expressed in most tissues and organs, except seeds, in which ANS may contribute to proanthocyanidin synthesis. One possible explanation for the lack of anthocyanins in the Caryophyllales is the suppression or limited expression of the DFR and ANS.     

叶片花色素苷对植物光合作用影响的研究进展

近年来,花色素苷在彩叶植物呈色机制的研究中备受关注,但目前有关其对彩叶植物光合特性影响的机制仍缺乏系统的评述。本文简单介绍了花色素苷的基本特性,并基于国内外相关研究进展,综述了叶片花色素苷对植物光合特性的影响机制及其对叶片光合机构的保护意义,对彩叶植物光合作用的研究方向提出了建磷。     

Anthocyanin Profiles in Grape Berry Skins of Different Species of Wine Grapes in Shanxi,China

To understand the anthocyanin characteristics of wine grape varieties, the anthocyanin composition and content of 31 wine grape varieties were analyzed to explore the use of anthocyanins as chemical fingerprints to distinguish varieties. Results showed that a total of 21 anthocyanins were detected in the skins, including cyanidin, delphinidin, petunidin, peonidin and malvidin 3-monoglucosides (or 3,5-diglucosides) along with the corresponding acetyl and p-coumaroyl derivatives. The highest and lowest total amount of anthocyanins were detected in ‘Ruby Cabernet’ and ‘Muscat Rouge’, respectively. In the 21 Vitis vinifera grapes, there were 3~11 monoglucoside anthocyanins detected, however, there were 4 to 9 monoglucoside anthocyanins and 1~7 diglucoside anthocyanins detected in the 10 other species of grapes. Except for ‘Zhesexiang’ ‘Seibel Noir’, ‘44-6-7-1’ and ‘Beibinghong’, the contents of diglucoside anthocyanins in the other six varieties accounted for more than 52% of the total anthocyanins. Except for ‘Zhesexiang’, ‘Muscat Rouge’ and ‘Beibinghong’, the content of methylated anthocyanins accounted for more than 75% of total anthocyanins. There were significant differences in the anthocyanin types and contents in the skins among V. vinifera and other grapes. The results of the principal component analysis and the cluster classification of 31 grape varieties (lines) were nearly consistent, which suggested that anthocyanins can be used as chemical fingerprints to distinguish wine grape varieties.     

高等植物花色苷在液泡中的存在状态及其着色效应

综述了花色苷被摄入液泡的原因、花色苷在液泡中的存在状态及其对植物细胞的着色效应。花色苷在植物细胞质中合成后转运到液泡里是为了解除其对蛋白质和DNA等细胞功能分子的毒性。花色苷的液泡区隔化是花色苷在植物细胞中发挥正常功能的前提。在大多数植物中,花色苷在绝大多数情况下完全溶解在液泡里。但是,花色苷也能在液泡里形成颗粒,这些颗粒可以划分为花色苷体和花色苷液泡包涵体两类。花色苷体由膜包裹,其形成是液泡中小的有色囊泡逐渐合并的结果,发育完全的花色苷体为典型的球状、具比液泡更深的红色;液泡里的花色苷体具高密度,呈现为含高浓度花色苷的不溶性小球;花色苷体的存在可导致液泡的强烈色彩。花色苷液泡包涵体可能具备蛋白质基质,既无膜包裹又无内部结构,其形成是转运进液泡的花色苷与蛋白质基质结合的结果;液泡里的花色苷液泡包涵体形状不规则,象果冻;在花色苷液泡包涵体中,花色苷可能通过氢键连接于蛋白质基质的一个有限空间位点;花色苷液泡包涵体被认为是液泡中花色苷的"陷阱",优先摄取花色素3,5-二糖苷或酰化的花色苷;花色苷液泡包涵体的存在可增加液泡色彩的强度并导致"蓝化"。     

Effects of anthocyanins and anthocyanin-rich extracts on the risk for cancers of the gastrointestinal tract

Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. Anthocyanins are responsible for most of the red, blue, and purple colors of fruits, vegetables, flowers, and other plant tissues or products. In recent years, numerous studies have shown that anthocyanins display a wide range of biological activities. This review summarises recent literature evidence on the association of anthocyanins and anthocyanin-rich extracts consumption with the risk for gastrointestinal tract cancer, concentrating on the results from in vivo animal model tumor systems, as well as data from human epidemiological studies. Potential cancer chemopreventive activities of anthocyanins were revealed from in vitro studies. In vivo animal model tumor systems showed that dietary anthocyanins inhibit cancers of the gastrointestinal tract. Some epidemiological studies have revealed protective effects of anthocyanins consumption on gastrointestinal cancer risk in humans. Pharmacokinetic data indicate that absorption of anthocyanins into the bloodstream of rodents and humans is minimal, suggesting that they may have little efficacy in tissues other than the gastrointestinal tract and skin. Future studies should be undertaken to determine if the anticancer effects of anthocyanins are due to the parent compounds and/or to their metabolites.