Main Components of Polyphenols of Trillium tschonoskii Maxim. and Changes under Different Se Concentrations

[Objectives] To analyze main components of polyphenols of Trillium tschonoskii Maxim. and study changes under different Se concentrations. [Methods] In this experiment,the Trillium tschonoskii Maxim. was used and spectrophotometry was applied to measure the total phenols in stems,leaves and rhizomes of Trillium tschonoskii Maxim. [Results]Total phenols in stems and leaves and rhizomes of Trillium tschonoskii Maxim. were 3. 026% and 0. 513% respectively,the content of total phenols in stems and leaves was 5. 9 times of that in rhizomes; total phenol extracting solution was analyzed through UV-Vis scanning,HPLC detection,and LC-MS; 3 main polyphenol compounds were obtained: chlorogenic acid,caffeic acid and rutin,in which chlorogenic acid and caffeic acid were firstly discovered in Trillium tschonoskii Maxim. and rutin was firstly discovered in stems and leaves of Trillium tschonoskii Maxim. HPLC method was used to measure the content of chlorogenic acid,caffeic acid,and rutin in stems and leaves of Trillium tschonoskii Maxim. under different Se concentrations. [Conclusions]The content of chlorogenic acid in stems and leaves of Trillium tschonoskii Maxim. increases with the increase of Se concentration,showing Se promotes Se accumulation and the maximum content of chlorogenic acid is 2. 58%; the content of caffeic acid in stems and leaves of Trillium tschonoskii Maxim. increases slightly with the Se concentration,showing the promotion of Se to accumulation of caffeic acid is not significant;the content of rutin in stems and leaves of Trillium tschonoskii Maxim. firstly increases then declines with the increase in Se concentration,at25 mg/kg Se concentration,rutin reached the maximum value,showing the promotion of Se to rutin accumulation is not significant.

Control Design and Implementation of a Spiral Spring Energy Storage System Connected to a Grid via PMSG

For an innovative spiral spring energy storage system,the permanent magnet synchronous generator(PMSG)is utilized as the energy conversion device due to its simple structure,low weight and high torque.During power generation,the output torque and moment of inertia of the spiral spring are changing continuously and simultaneously and the parameters of the PMSG show uncertainties.Furthermore,the DC link voltage of the converter should be stable and the power injected into the grid needs to be controlled.First,the change features of the external power source and the uncertainties of the generator’s internal parameters are expressed as the comprehensive disturbances,which are introduced into the dynamic model of the PMSG and also modify the dynamic model.Then,the high gain observers are utilized to estimate the comprehensive disturbances,and an improved robust backstepping control scheme integrating L2 gain and high gain observers is proposed.Secondly,the gridside inverter controller for the DC voltage loop and reactive power loop is designed based on the backstepping theory.Finally,hardware implementation is fulfilled to verify the presented algorithm.The results show that high gain observers are able to accurately estimate the external and internal interferences;the proposed control scheme can effectively suppress the external and internal interferences and guarantees output current,operating speed of the PMSG and output reactive power to correctly track respective references,and effectively stabilize the DC link voltage.

A Thylakoid Membrane Protein Functions Synergistically with GUN5 in Chlorophyll Biosynthesis

Chlorophyll(Chl)is essential for photosynthetic reactions and chloroplast development.While the enzymatic pathway for Chl biosynthesis is well established,the regulatory mechanism underlying the homeostasis of Chl levels remains largely unknown.In this study,we identified CBD1(Chlorophyll Biosynthetic Defect1),which functions in the regulation of chlorophyll biosynthesis.The CBD1 gene was expressed specifically in green tissues and its protein product was embedded in the thylakoid membrane.Furthermore,CBD1 was precisely co-expressed and functionally correlated with GUN5(Genome Uncoupled 5).Analysis of chlorophyll metabolic intermediates indicated that cbd1 and cbd1gun5 mutants over-accumulatedmagnesium protoporphyrin Ⅸ(Mg-Proto Ⅸ).In addition,the cbd1 mutant thylakoid contained less Mg than the wild type not only as a result of lower Chl content,but also implicating CBD1 in Mg transport.This was supported by the finding that CBD1 complemented a Mg^(2+)uptake-deficient Salmonella strain under low Mg conditions.Taken together,these results indicate that CBD1 functions synergistically with CHLH/GUN5 in Mg-Proto IX processing,and may serve as a Mg-transport protein to maintain Mg homeostasis in the chloroplast.