草莓果实成熟期花青苷、酚类物质和类黄酮含量的变化

以春星和全明星为试材,研究了不同成熟度草莓果实酚类物质、类黄酮及花青苷的动态变化。结果表明,随着果实的成熟,酚类物质和类黄酮在绿熟期有较高的含量,之后随着果实的成熟先下降,至紫红期又开始大量积累;花青苷含量随着果实的成熟逐渐增加,紫红期达最大值;低温贮藏的草莓果实酚类物质、类黄酮含量首先下降,之后随着贮藏天数的增加而不断上升;花青苷含量逐渐增加,但增加的趋势比较缓慢。     

高温条件下芥蓝菜薹色泽的形成

通过对高温条件下3个芥蓝品种菜薹色素及其相关因素研究,结果表明:芥蓝菜薹的叶绿素、花青苷和类黄酮含量尖叶夏芥蓝均为最高,荷塘芥蓝次之,中花芥蓝最低。尖叶夏的有机酸含量最高,中花次之,荷塘最低。花青苷含量较高的品种,其苯丙氨酸解氨酶(PAL)活性也比较高。芥蓝菜薹表皮色泽是叶绿素、类黄酮和花青苷等色素的综合表现,并受表皮酸碱性的影响。     

拟南芥种皮色素形成机制的研究进展

类黄酮为拟南芥种皮的主要成色物质,其生物合成过程受到一系列基因的影响.这些基因中,一部分为结构基因(TT4、TT5、TT6、TT7、FLS1TT3,LDOX和BAN)编码一些酶类参与到类黄酮的生物合成;一部分作为调控基因(TT1,TT2,TT8,TTG1,TTG2和TT16)编码一些酶对生物合成途径起调控作用;另外一些基因(TT12,TT19)编码与色素转运、积累相关的蛋白质。这些基因中的一种或几种发生变异就能影响到类黄酮的生物合成,从而引起拟南芥种皮色泽的变异。在此,就拟南芥种皮的色泽变异及类黄酮生物合成机理作一介绍。     

Effects of fruit bagging on coloring and related physiology,and qualities of red Chinese sand pears during fruit maturation

Red Chinese sand pears (Pyrus pyrifolia Nakai) are particular to China. In order to determine the effects of fruit bagging treatments (including bag types, bag removal patterns and dates) on fruit qualities and to understand the mechanism of coloring of red Chinese sand pears, two experiments were carried out. In the first experiment, fruit of ‘Meirensu’ were firstly covered by light-impermeable paper bags with different levels of light permeable liners during their early development stage, then, the whole bag were/not removed or only the outer layer of bags were removed 3, 2 or 1 weeks before harvest. Thus, the fruit were/not totally re-exposed or were under different levels of sunlight transmission (80.31% or 34.71%). Non-bagged fruit were used as the control. Bagging treatments significantly affected the concentration of anthocyanin and the visual qualities of pear fruit. Compared to control, fruit re-exposed totally for 2 or 3 weeks accumulated the largest amount of anthocyanin and fruit receiving 80.31% and 34.71% of sunlight for 1–3 weeks could synthesize a little anthocyanin, indicating that high light intensity is imperative for coloring in red Chinese sand pears. Bagging treatments did not affect contents of total soluble sugars, but decreased organic acids contents in fruit. In the second experiment, fruit of ‘Meirensu’ and ‘Yunhongli No. 1’ were covered with only one type of light-impermeable bag during the early development stage and totally re-exposed after the bag removal 15 days before harvest. Fruit were then collected at different intervals to trace the time-course of coloring, and related physiology and inner qualities. With increasing time after the bag removal, the concentration of chlorophyll, carotenoid, flavonoid and total phenols changed little, but the concentration of anthocyanin accumulated extremely fast within 10 days after the bag removal in both cultivars and thereafter kept constant. ‘Yunhongli No. 1’ had higher anthocyanin contents and lower hue angle than ‘Meirensu’, indicating a higher potential of anthocyanin synthesis. After the bag removal, the sucrose contents and PAL activities increased gradually and correlation analysis revealed that they were highly correlated with anthocyanin accumulation in two cultivars. This study suggests that anthocyanin biosynthesis in red Chinese sand pears is a highly light dependent process and modified by genotypes. Based on the current results, in order to obtain red Chinese sand pear fruit with attractive appearance and good inner qualities, fruit must be covered with light-impermeable bags at the early stage of fruit development and the bag should be removed totally at least 10 days before harvest.     

无梗五加果黄酮的测定及提取方法的研究

以无梗五加的果实为原料,采用乙醇回流法提取黄酮,用分光光度法测定提取液中黄酮含量,以确定提取的最佳工艺。结果表明:硝酸铝显色法适于无梗五加果黄酮含量的测定,回收率为98.35%。乙醇回流提取无梗五加果黄酮的最佳工艺为:浓度50%乙醇,液固比为1∶80、提取时间4h,提取1次。     

瑞香狼毒化学成分抑制PC-12细胞神经突起生长活性研究

对瑞香狼毒(Stellera chamaejasme L.)的化学成分进行研究,采用硅胶色谱、凝胶色谱、高效液相色谱等多种色谱手段对瑞香狼毒的乙酸乙酯提取物进行分离纯化,利用NMR、MS波谱分析鉴定3个木质素、1个二萜原酸酯、3个双黄酮、2个黄酮。枇杷素(5)、异落叶松树脂醇(7)和(-)-落叶松树脂醇(8)为首次从该植物中分离得到。PC-12细胞活性试验表明,双黄酮类化合物(狼毒色原酮(2),新狼毒素B(3),异新狼毒素A(4))对NGF依赖的PC-12细胞突起生长有较强的抑制活性(P0.05)。     

丛生竹黄酮类化合物的分析研究及其在分类上的应用

本文分析了9属30种国产丛生竹中的黄酮类化合物,表明丛生竹中含有较丰富的黄酮成分,对丛生竹的分类有一定的应用价值;同时也表明丛生竹在黄酮成分上与散生竹及其它禾本科种类的区别与某些一致性。     

蓝光连续光照对大豆芽苗菜类黄酮合成的影响

以黑暗培养(D)为对照,阐明了蓝光(B)连续光照对大豆(Glycine max L.Merr.)芽苗菜品种东农690生长和类黄酮合成的影响。结果表明:与对照组相比,蓝光连续光照36 h显著提高了大豆芽苗菜子叶中山奈酚(kaempferol)和黄豆苷元(daidzein)的含量,同时子叶中蓝光光受体基因CRY1、CRY2,类黄酮合成相关基因IFS的表达量也显著提高。处理组中,大豆芽苗菜下胚轴中黄豆苷(daidzin)含量逐渐增加,黄豆苷元(daidzein)、染料木素(genistein)、染料木苷(genistin)和山奈酚(kaempferol)的含量先升高后下降,但在36 h时均显著高于黑暗处理。在蓝光光照6和24 h时,大豆芽苗菜下胚轴中苯丙氨酸解氨酶(PAL)与查尔酮异构酶(CHI)活性与对照组相比均显著提高。类黄酮合成途径相关基因PAL、CHS、ANS、IFS的表达量在蓝光处理下均是先升高后下降,而蓝光光受体基因CRY1与CRY2的表达量随着光照时间延长逐渐升高。     

不同采收季节对叶用芥菜类黄酮物质含量和抗氧化活性的影响

 以10个不同基因型叶用芥菜为试材, 研究了不同采收季节对其总酚含量、类黄酮含量和抗氧化活性的影响。结果表明春季采收的总酚含量、抗氧化活性显著高于冬季采收的。叶用芥菜含有槲皮素和山奈素两种类黄酮化合物, 春季采收的槲皮素和山奈素含量高于冬季采收的。基因型间总酚、槲皮素和山奈素的含量及抗氧化活性均存在较大的差异, 并与生长季节有极显著的互作关系, 表明生长季节对不同基因型叶用芥菜酚类物质积累和抗氧化活性有较大的影响。总酚、槲皮素和山奈素的含量分别与抗氧化活性呈极显著和显著正相关。     

Metabolie Engineering of Flower Color in Ornamental Plants

Abstract

Advances in the knowledge of plant pigment pathways at genetic, biochemical and molecular levels, and the establishment of genetic transformation methods for an increasing number of plant species have paved the way to genetic engineering of flower and plant color for ornamental purposes. From trial-and-error approaches based on the available few genes, the trend is now to comprehensively study the target species, genotypes and pigment pathways to precisely address specific breeding goals. This review examines the state of the art in this field, from the pioneering stages to fundamental and applied research on flavonoids, which is being extended to carotenoids and is also likely to involve other pigments in the near future.