Effects of Pigment Indicators on the Color Expression of Leaves of the Colored-leaf Garden Plants

[Objective] In this study, the relationship between the pigments and the color expression of leaves of colored-leaf plants was discussed. [Method] The colors of leaf blades of 6 kinds of plants were analyzed with the Royal Horticultural Soci-ety Colour Chart. The chlorophyl content, carotenoids content and anthocyanin con-tent in leaf blades were determined. In addition, the color types of leaf blades, kinds of pigments, pigment contents and pigment distributions of 6 kinds of plants were compared. [Result] The chlorophyl contents ranked as Populus canadensis Moench （green leaves） 〉 Populus deltoids cv. Zhonghuahongye （purple green leaves） 〉 Populus euramericana cv. Quanhong （red leaves）; Acer palmatum Thunb. （green leaves） 〉 Acer palmatum cv. Atropurpureum （purple red leaves） 〉 Acer pal-matum Thunb. cv. Atropurpureum （red leaves）. The ranking of anthocyanin contents was just opposite. The chlorophyl content was negatively related to the anthocyanin content. The leaf color of plants is determined by various pigments. The more the chlorophyl is, the greener the leaf is. The more the anthocyanin is, the redder the leaf is. In the colored-leaf plants, the chlorophyl content represents about 80% of the content of pigments, the carotenoids content represents about 17%, and the an-thocyanin represents about 3%. There is a difference in the chlorophyl content be-tween colored-leaf plants and green plants. However, the relatively low chlorophyl content wil not hamper the normal life activities of colored-leaf plants. [Conclusion] We hoped to provide reference and basis for the production and landscaping of col-ored-leaf plants.

Phytotoxicity in seven higher plant species exposed to di-n-butyl phthalate or bis （2-ethylhexyl） phthalate

We investigated phytotoxicity in seven plant species exposed to a range of concentrations （0- 500 mg· kg^-1 soil） of di-n-butyl phthalate （DnBP） or his （2- ethylhexyl） phthalate （DEHP）, two representative phthalate esters （PAEs） nominated by USEPA as priority pollutants and known environmental estrogens. We studied seed germination, root elongation, seedling growth, biomass （fresh weight, FW） and malondialdehyde （MDA） content of shoots and roots of wheat （Triticum aestivum L.）, alfalfa （Medicago sativa L.）, perennial ryegrass （Lolium perenne）, radish （Raphanus sativus L.）, cucumber （Cucumis sativus L.）, oat （Avena sativa） and onion （Allium cepa L.）, together with monitoring of plant pigment content （chlorophyll a, b and earotinoids） in alfalfa, radish and onion shoots. Root elongation, seedling growth and biomass of the test species were generally inhibited by DnBP but not by DEHP, indicating a lower level of phytotoxicity of DEHP than of DnBP. MDA contents of four species were promoted by PAE exposure, but not in alfalfa, ryegrass or onion shoots, indicating lower sensitivity of these three species to PAE pollutants. Plant pigment contents were clearly affected under the stress of both pollutants, implying the potential damage to the photosynthetic system of test plants, mainly by decreasing the content of chlorophyll a and b. Results of DnBP and DEHP phytotoxicity to the primary growth of test plants has provided information for the assessment of their environmental risk in the soil and also forms a basis for the further analysis of their toxic effects over the whole growth period of different plant species.

＂La Vie en Rose＂： Biosynthesis, Sources, and Applications of Betalain Pigments

Betalains are tyrosine-derived red-violet and yellow pigments found exclusively in plants of the Caryophyllales order, which have drawn both scientific and economic interest. Nevertheless, research into betalain chemistry, biochemistry, and function has been limited as comparison with other major classes of plant pigments such as anthocyanins and carotenoids. The core biosynthetic pathway of this pigment class has only been fully elucidated in the past few years, opening up the possibility for betalain pigment engineering in plants and microbes. In this review, we discuss betalain metabolism in light of recent advances in the field, with a current survey of characterized genes and enzymes that take part in be- talain biosynthesis, catabolism, and transcriptional regulation, and an outlook of what is yet to be discovered. A broad view of currently used and potential new sources for betalains, including utilization of natural sources or metabolic engineering, is provided together with a summary of potential applications of beta- lains in research and commercial use.

Exploring the influence of crystal packing on the optical-physical property of quercetin-based binary and ternary solid forms

The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis.Although the crystal system of Qur-DPDSMe OH and Qur-DPDS-Dioxane is the same,the desolvation results revealed that Qur-DPDS-Me OH transformed to Qur-DPDS when Me OH solvent molecules escape from the lattice,while Qur-DPDS-Dioxane transformed to Qur-DPDS-II through a similar process,which is same with Qur-DPDS-THF.These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-II obey an enantiotropic relationship.Moreover,the formation of cocrystal solvates improves the packing efficiency of crystals.Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns,thus bring different physicochemical properties.Finally,the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.

Transcriptome and Metabolic Profiling Provides Insigh into Betalain Biosynthesis and Evolution in Mirabilis jalapa

Betalains are tyrosine-derived pigments that occur solely in one plant order, the Caryophyllales, where they largely replace the anthocyanins in a mutually exclusive manner. In this study, we conducted multi-species transcriptome and metabolic profiling in Mirabilisjalapa and additional betalain-producing species to identify candidate genes possibly involved in betalain biosynthesis. Among the candidates identified, betalainrelated ytochrome P450 and glucosyltransferase-type genes, which catalyze tyrosine hydroxylation or （hydroxy）cinnamoyl-glucose formation, respectively, were further functionally characterized. We detected the expression of genes in the flavonoid/anthocyanin biosynthetic pathways as well as their metabolite intermediates in betalain-accumulating M. jalapa flowers, and found that the anthocyanin-related gene ANTHOCYANIDIN SYNTHASE （MjANS） is highly expressed in the betalain-accumulating petals. However, it appears that MjANS contains a significant deletion in a region spanning the corresponding enzyme active site. These findings provide novel insights into betalain biosynthesis and a possible explanation for how anthocyanins have been lost in this plant species. Our study also implies a complex, non-uniform history for the loss of anthocyanin production across betalain producers, previously assumed to be strictly due to diminished expression of anthocyanin-related genes.