Antioxidant andα-glucosidase inhibitiory activity of Cercis chinensis flowers

Antioxidant andα-glucosidase inhibitiory active compounds of Cercis chinensis flowers were investigated with bio-assay guiding method.Ethyl acetate fraction(CLEa)and n-butanol fraction(CLBu)exhibited antioxidant andα-glucosidase inhibitiory activity in vitro,and the corresponding active fractions,EaFr.3,EaFr.5 and BuFr.1,exhibited higher antioxidant andα-glucosidase inhibitiory activity than those of other fractions.Eight compounds,ethyl gallate(1),stearic acid(2),docosanoic acid(3),5α-stigmast-9(11)-en-3β-ol(4),kaempferol-3-O-α-rhamnopyranoside(5),vanillic acid(6),fisetin(7),andβ-sitosterol(8),were isolated and identified from CLEa and CLBu.Ethyl gallate shown the highest antioxidant activity by scavenging DPPH radical and reducing ferric compared.Docosanoic acid and vanillic acid shown strongerα-glucosidase inhibitory activity than that of acarbose.

Effects of nutrition spatial heterogeneity on root traits and carbon usage by roots of Cercis chinensis seedlings in split root rooms

In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length （SRL） of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nutrition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches.

Carbon unloading in roots in relation to root senescence in Cercis chinensis seedlings under drought stress

When Cercis chinensis seedlings suffered from drought treatment, net photosynthetic rates had been significantly reduced at the end of the drought treatment. Compared with the control, the activities of acid invertases in roots had increased 5 and 11 days after drought treatment. Seventeen days after drought treatment, the activities of acid invertases in roots were significantly decreased, while activities of alkaline invertases in roots had also been significantly reduced. As the moisture in culture media decreased, so the activities of sucrose synthases in leaves decreased slightly. In roots, their activities had significantly increased 5 and 11 days after drought treatment. The contents of fructose in roots reduced as the moisture in culture media decreased and 11 and 17 days after drought treatment the reduction was significant. The content of glucose in roots clearly did not change as drought stress occurred further, but was still less than that in the control seedlings. Similarly, the content of sucrose reduced as the moisture in culture media decreased. At the beginning of the drought stress, the content of sucrose was significantly higher than that in the control and afterwards there were no differences between drought-treated seedlings and the control. The gradient of the sucrose content between leaves and roots was 0.0982 mg.g^-1 FW 17 days after drought treatment, while the gradient of the seedlings under normal condition was 1.3832 mg.g^-1 FW. The sucrose concentration gradient reduced by 92.9%. The reduction in the sucrose content gradient under drought stress decreased the sucrose partitioning in roots. Therefore, our results support the hypothesis of‘shared control＇.

The nearly complete assembly of the Cercis chinensis genome and Fabaceae phylogenomic studies provide insights into new gene evolution

Fabaceae is a large family of angiosperms with high biodiversity that contains a variety of economically important crops and model plants for the study of biological nitrogen fixation.Polyploidization events have been extensively studied in some Fabaceae plants,but the occurrence of new genes is still concealed,owing to a lack of genomic information on certain species of the basal clade of Fabaceae.Cercis chinensis(Cercidoideae)is one such species;it diverged earliest from Fabaceae and is essential for phylogenomic studies and new gene predictions in Fabaceae.To facilitate genomic studies on Fabaceae,we performed genome sequencing of C.chinensis and obtained a 352.84 Mb genome,which was further assembled into seven pseudochromosomes with 30612 predicted protein-coding genes.Compared with other legume genomes,that of C.chinensis exhibits no lineage-specific polyploidization event.Further phylogenomic analyses of 22 legumes and 11 other angiosperms revealed that many gene families are lineage specific before and after the diversification of Fabaceae.Among them,dozens of genes are candidates for new genes that have evolved from intergenic regions and are thus regarded as de novo-originated genes.They differ significantly from established genes in coding sequence length,exon number,guanine–cytosine content,and expression patterns among tissues.Functional analysis revealed that many new genes are related to asparagine metabolism.This study represents an important advance in understanding the evolutionary pattern of new genes in legumes and provides a valuable resource for plant phylogenomic studies.

A New Stilbene from Cercis chinensis Bunge

To study new natural products, we used ODS （YMC, Kyoto, Japan） and silica gel column chromatography to separate compounds in Cercis chinensis Bunge （Leguminosae）. A new stilbene, trans- 3, 5, 3＇, 4＇-tetrahydroxy-4-methylstilbene （1）, along with 10 known compounds, namely piceatannol （2）, dihydromyricetin （3）, catechin （4）, dihydrorobinetin （5）, menisdaurin （6）, lithospermoside （7）, teatannin （8）, dasycarponin （9）, β-sitosterol （10）, and daucosterin （11）, was isolated from C. chinensis. Their structures were elucidated on the basis of spectroscopic evidence. Compounds 2-6 and 9 were isolated from the genus Cercis Linn. for the first time.