Central-cell-produced attractants control fertilization recovery.

Animal fertilization relies on hundreds of sperm racing toward the egg, whereas, in angiosperms, only two sperm cells are delivered by a pollen tube to the female gametes (egg cell and central cell) for double fertilization. However, unsuccessful fertilization under this one-pollen-tube design can be detrimental to seed production and plant survival. To mitigate this risk, unfertilized-gamete-controlled extra pollen tube entry has been evolved to bring more sperm cells and salvage fertilization. Despite its importance, the underlying molecular mechanism of this phenomenon remains unclear. In this study, we report that, in Arabidopsis, the central cell secretes peptides SALVAGER1 and SALVAGER2 in a directional manner to attract pollen tubes when the synergid-dependent attraction fails or is terminated by pollen tubes carrying infertile sperm cells. Moreover, loss of SALs impairs the fertilization recovery capacity of the ovules. Therefore, this research uncovers a female gamete-attraction system that salvages seed production for reproductive assurance.

Rapid identifying of COX-2 inhibitors from turmeric (Curcuma longa) by bioaffinity ultrafiltration coupled with UPLC-Q Exactive-Orbitrap-MS and zebrafish-based in vivo validation.

Turmeric (Curcuma longa), a typical source with recognized anti-inflammatory activity, is one such medicine-food homology source, yet its anti-inflammatory mechanisms and specific component combinations remain unclear. In this study, a net fishing method combining bio-affinity ultrafiltration and ultra-high performance liquid chromatography-mass spectrometry (AUF-LC/MS) was employed and 13 potential COX-2 inhibitors were screened out from C. longa. 5 of them (C1, 17, 20, 22, 25) were accurately isolated and identified. Initially, their IC50 values were measured (IC50 of C1, 17, 20, 22 and 25 is 55.08, 48.26, 29.13, 111.28 and 150.48 µM, respectively), and their downregulation of COX-2 under safe concentrations (400, 40, 120, 50 and 400 µM for C1, 17, 20, 22 and 25, respectively) was confirmed on RAW 264.7 cells. Further, in transgenic zebrafish (Danio rerio), significant anti-inflammatory activity at safe concentrations (15, 3, 1.5, 1.5 and 3 µg/mL for C1, 17, 20, 22 and 25, respectively) were observed in a dose-dependent manner. More importantly, molecular docking analysis further revealed the mode of interaction between them and the key active site residues of COX-2. This study screened out and verified unreported COX-2 ligands, potentially accelerating the discovery of new bioactive compounds in other functional foods.

Facile synthesis of Ni3Se4/Ni0.6Zn0.4O/ZnO nanoparticle as high-performance electrode materials for electrochemical energy storage device.

To enhance the performance of transition metal chalcogenide composite electrode material, a key point is a composite design and preparation based on the synergistic effect between the oxide and selenide materials. With a facile 'one step template-annealing' step, Ni3Se4, Ni0.6Zn0.4O and ZnO are simultaneously synthesized, by 500 °C annealing. With the increase of annealing temperature from 350 °C to 600 °C, nickel selenides change from NiSe2to Ni3Se4to NiSe. The charge storage capacity increases first and then decreases with the increase of annealing temperature, and the 500 °C annealing obtained three compound composite Ni3Se4/Ni0.6Zn0.4O/ZnO (NNZ-500) nanoparticle material displayed a high specific capacitance of 1089.2 F g-1at 1 A g-1, and excellent cycle stability of 99.8% capacitance retention after 2000 cycles at 5 A g-1. Moreover, an asymmetric supercapacitor was assembled with NNZ-500 as the positive electrode material and activated carbon as the negative electrode material. This kind of asymmetric supercapacitor demonstrated a high energy density of 53.4 Wh kg-1at 819.0 W kg-1, and cycle stability with 98.6% capacitance retention after 2000 cycles. This material preparation approach provides great potential for the future development of high performance transition metal composite electrode materials in energy storage applications.

Dieckmann Condensation of Ugi N-Acylamino Amide Product: Facile Access to Functionalized 2,2-Disubstituted Indolin-3-ones.

Structurally unique 2,2-disubstituted indolin-3-ones with a quaternary carbon center have been constructed through a novel C-C bond formation at the C3 position of Ugi N-acylamino amide adducts employing an organic base-mediated Dieckmann condensation. This facile, flexible protocol can be fine-tuned to construct drug-like pyrazino[1,2-a]indole fragments with the same quaternary carbon center only through the variation of the acid part in Ugi input. This novel and expeditious methodology has a broad scope and can rapidly generate the drug-like indolin-3-one core.

UPLC-Q-Exactive/MS-based metabonomics revealed protective effect of Zingiberis rhizome and its processed product on deficiency-cold and hemorrhagic syndrome rats.

Zingiberis rhizome carbonisata (ZRC) is the processed product of Zingiberis rhizome (ZR). ZR is mainly used for warming the spleen and stomach to dispel cold, whereas ZRC is commonly applied as a treatment for deficiency-cold and hemorrhagic syndrome (DCHS). Although they have long been used to serve different clinical purposes, the specific action mechanism of the drugs and molecular changes underlying ZR processing are not clear. In this study, metabolomics study was carried out to analyze the alterations in endogenous metabolites in serum and urine samples of DCHS rat models using ultra-high-performance liquid chromatography coupled with quadrupole-Exactive mass spectrometry technique and constructed principal component analysis score plots that showed that the ZRC group was completely separated from the DCHS and ZR groups but demonstrated a highly close plotting to the normal control group. The results revealed that both ZR and ZRC intervened in the metabolic pathways of DCHS models but to varying degrees and with different influencing factors. In addition, ZRC was found to function as a treatment for the metabolic disorders of DCHS through 15 pharmacodynamic biomarkers involving a series of pathways, such as glycine, serine, and threonine metabolic pathway, as well as arachidonic acid metabolic pathways. This study showed that metabolomics method based on ultra-high-performance liquid chromatography coupled with quadrupole-Exactive mass spectrometry could preliminarily illuminate the therapeutic mechanism of ZR and ZRC on DCHS and the changes in ZR processing from the molecular-level perspective. The results also provided new insight into further research on DCHS treatment.

Evolution of volatile profile and aroma potential of 'Gold Finger' table grapes during berry ripening.

BACKGROUND: 'Gold Finger' is a grape cultivar with a finger-like shape and a milk flavor. The process by which its aroma profile evolves during ripening is unclear. Thus, changes in the free and bound volatile compounds present in 'Gold Finger' grapes during ripening were investigated using headspace sampling-solid-phase microextraction-gas chromatography-mass spectroscopy (HS-SPME-GC-MS). RESULTS: A total of 83 volatile aroma components were identified in the grapes, with aldehydes, esters, acids, and alcohols being the main components. The total aroma compound content exhibited significant differences between the bound and free forms. The total content of bound volatile compounds did not change significantly during fruit development, although the free aroma compound content was significantly higher than the bound content. The total content of free aldehydes, free alcohols, bound norisoprenoids, and ketones gradually increased for up to 70 days after flowering (DAF), while the total free ester, terpene, and acid content decreased. The characteristic aroma compounds of 'Gold Finger' grapes were identified as hexanal, (E)-2-hexenal, and ethyl hexanoate. CONCLUSIONS: These results give a foundation for the further development of 'Gold Finger' grapes and provide a theoretical basis for the selection and breeding of novel aromatic grape varieties. © 2021 Society of Chemical Industry.

[Quality markers of Zingiberis Rhizoma Carbonisata before and after processing].

Based on the previous research results of our group and literature research, the chemical components, mechanisms, pharmacodynamics, and pharmacokinetics of Zingiberis Rhizoma Carbonisata were summarized to determine the quality markers(Q-markers) of Zingiberis Rhizoma Carbonisata and Zingiberis Rhizoma. Our research group has clarified the differential components of Zingiberis Rhizoma Carbonisata and Zingiberis Rhizoma, the meridian-warming hemostatic effect of Zingiberis Rhizoma Carbonisata, the related targets and pathways of the effect, the endogenous biomarkers of Zingiberis Rhizoma Carbonisata, and the hemodynamic processes of Zingiberis Rhizoma Carbonisata and Zingiberis Rhizoma. Moreover, based on high-performance liquid chromatography-diode array detector-electrospray ionization mass spectrometry(HPLC-DAD-ESIMS), a method for determining the content of Q-mar-kers was established. In conclusion, the study finally determined that gingerone, 6-shogaol, and diacetyl-6-gingerol were the Q-mar-kers of Zingiberis Rhizoma Carbonisata decoction pieces, and 6-gingerol, 8-gingerol, and 10-gingerol were Q-markers of Zingiberis Rhizoma decoction pieces. The result is expected to provide a reference for the establishment of quality standards for Zingiberis Rhizoma Carbonisata decoction pieces and Zingiberis Rhizoma decoction pieces.

Biochemical characterization and redesign of the coenzyme specificity of a novel monofunctional NAD+-dependent homoserine dehydrogenase from the human pathogen Neisseria gonorrhoeae.

Gonorrhoea, caused by Neisseria gonorrhoeae, is a major global public health concern. Homoserine dehydrogenase (HSD), a key enzyme in the aspartate pathway, is a promising metabolic target against pathogenic infections. In this study, a monofunctional HSD from N. gonorrhoeae (NgHSD) was overexpressed in Escherichia coli and purified to >95% homogeneity for biochemical characterization. Unlike the classic dimeric structure, the purified recombinant NgHSD exists as a tetramer in solution. We determined the enzymatic activity of recombinant NgHSD for l-homoserine oxidation, which revealed that this enzyme was NAD+ dependent, with an approximate 479-fold (kcat/Km) preference for NAD+ over NADP+, and that optimal activity for l-homoserine oxidation occurred at pH 10.5 and 40 °C. At 800 mM, neither NaCl nor KCl increased the activity of NgHSD, in contrast to the behavior of several reported NAD+-independent homologs. Moreover, threonine did not markedly inhibit the oxidation activity of NgHSD. To gain insight into the cofactor specificity, site-directed mutagenesis was used to alter coenzyme specificity. The double mutant L45R/S46R, showing the highest affinity for NADP+, caused a shift in coenzyme preference from NAD+ to NADP+ by a factor of ~974, with a catalytic efficiency comparable with naturally occurring NAD+-independent homologs. Collectively, our results should allow the exploration of drugs targeting NgHSD to treat gonococcal infections and contribute to the prediction of the coenzyme specificity of novel HSDs.

Screening of high-efficiency and low-toxicity antitumor active components in Macleaya cordata seeds based on the competitive effect of drugs on double targets by a new laminar flow chip.

It is urgent to obtain targeted drugs that selectively bind to pathological targets rather than physiological targets in the early stage of drug screening. G-Quadruplex has become one of the important targets in the development of anti-tumor drugs. However, drugs that target quadruplexes may also bind to dsDNA, which may lead to adverse reactions. In this study, a new three-phase laminar flow chip was constructed to enable the multi-components of a traditional Chinese medicine extract to dynamically and competitively bind with G-quadruplex DNA (on target) and double-stranded DNA (off target), so as to select high-efficiency and low-toxicity anti-tumor drugs. The results showed that there were five compounds in the extracts of Macleaya cordata seeds that exhibited obvious differences in binding to the two targets. Furthermore, the binding constants and modes of four identified alkaloids as they bound to two DNA targets were verified by fluorescence spectra and molecular docking methods. The toxicity to HepG2 and LO2 cells from the four alkaloids was also compared. The results showed that sanguinarine and chelerythrine could be used as candidate drugs with stronger binding to HT24 than DNA26. The chip can also be used for other types of double-target screening of other traditional Chinese medicine extracts or compound libraries.

A facile reaction to access novel structural sulfonyl-hybridized imidazolyl ethanols as potential DNA-targeting antibacterial agents.

A novel type of sulfonyl-hybridized imidazolyl ethanols as potential DNA-targeting antibacterial agents was constructed via the unique ring-opened reaction of oxiranes by imidazoles for the first time. Some developed target hybrids showed potential antimicrobial potency against the tested microbes. Especially, imidazole derivative 5f could strongly suppressed the growth of MRSA (MIC = 4 µg/mL), which was 2-fold and 16-fold more potent than the positive control sulfathiazole and norfloxacin. This compound exhibited quite low propensity to induce bacterial resistance. Antibacterial mechanism exploration indicated that compound 5f could embed in MRSA DNA to form steady 5f-DNA complex, which possibly hinder DNA replication to exert antimicrobial behavior. Molecular docking showed that molecule 5f could bind with dihydrofolate synthetase through hydrogen bonds. These results implied that imidazole derivative 5f could be served as a promising molecule for the exploration of novel antibacterial candidates.

LC-MS based plasma metabolomics study of the intervention effect of different polar parts of Hawthorn on hyperlipidemia rats.

Hawthorn, a well-known traditional Chinese medicine is used for the treatment of dyspepsia syndrome, cardiovascular disease, and hyperlipidemia. Hawthorn has complex composition. However, the effective fraction and mechanisms of action in alleviating hyperlipidemia are unknown. Therefore, the aim of this study was to evaluate the effects of four different polar components of hawthorn on hyperlipidemia rats, and to explore underlying mechanisms of action through liquid chromatography-mass spectrometry based plasma metabolomics. Hyperlipidemia rat model was established by feeding rats using a high-fat diet. High-fat model rats were then treated with four polar components of hawthorn for 14 consecutive days. Plasma samples were collected and subjected to biochemical and metabolomics analysis. Biochemical analysis showed that hawthorn n-butanol and ethyl acetate extracts had the highest efficacy on hyperlipidemia rats. Water fraction showed a partial effect, whereas petroleum ether extract was not effective against hyperlipidemia rats. Furthermore, liquid chromatography-mass spectrometry metabolomics analysis showed that the most effective fraction of hawthorn reversed the metabolic disorder in plasma of hyperlipidemia rats. Metabolomics analysis showed that hawthorn exerts its activity by modulating lipid metabolism, energy metabolism, oxidative stress, and amino acid metabolism.

[Analysis of volatile oil components of different species of Curcumae Rhizoma based on GC-MS and chemometrics].

The volatile oil of Curcumae Rhizoma has many active components,which are the key to the quality of Curcumae Rhizoma. Exploring the difference between volatile oil of different kinds of Curcumae Rhizoma facilitates the quality control and rational application of resources. In this study,GC-MS was applied to realize online qualitative and semi-quantitative analysis of the chemical composition spectrum of volatile oil from Curcuma wenyujin( CW),C. phaeocaulis( CP),and C. kwangsiensis( CK). Forty components were identified and their fingerprints were compared and evaluated. Hierarchical cluster analysis( HCA),principal component analysis( PCA),and orthogonal partial least squares discrimination analysis( OPLS-DA) were adopted to analyze the overall and outlier data. The results showed that the whole data could be divided into three kinds according to each analysis mode,and the volatile components of Curcumae Rhizoma vary greatly among species. PCA explored the difference between outliers and the mean value of the group and found that some volatile oils from CW may be greatly affected by the origin. By OPLS-DA,the samples from Zhejiang were able to gather,but those from Guizhou remained isolated,indicating the influence of growing environment on Curcumae Rhizoma metabolites. Based on VIP results combined with the heat map,characteristic volatile oil components of Curcumae Rhizoma from different varieties were screened out: curdione and linalool for CW; 2-undecanone for CP; humulene,γ-selinene,and zederone for CK. The GCMS method established in this study describes Curcumae Rhizoma samples comprehensively and accurately,and the characteristic components screened based on chemometrics can be used to distinguish Curcumae Rhizoma from different varieties and give them unique pharmacodynamic significance,which is fast,convenient,stable,and reliable and supports the rational application of Curcu-mae Rhizoma resources. It is found that the region of origin has great influence on CW,which is worthy of further study.

Nine absorbed components pharmacokinetic of raw and processed Moutan Cortex in normal and blood-heat and hemorrhage syndrome model rats.

Raw Moutan Cortex (RMC) and Processed Moutan Cortex (PMC) have a long history of use in China and other Asian countries. In this study, a rapid and accurate ultra-high-pressure liquid chromatography coupled with diode array detector (UHPLC-DAD) method was developed and validated for the simultaneous determination of nine absorbed compounds of RMC/PMC. After extraction by protein precipitation with methanol from plasma, the analytes were separated on an Acquity UPLC® BEH Shield RP18 column (2.1 × 100 mm, 1.7 µm, Waters, USA). Acetonitrile (A) and 0.1% (v/v) formic acid in water (B) were selected as the mobile phase to perform gradient elution. The linearity of nine analytes was >0.9915. The intra- and inter-assay precision (RSD) values were within 11.18%, and accuracy ranged from 91.32 to 101.29%. Suitable stability, matrix effect and extraction recoveries were also obtained. The validated method was applied to compare the pharmacokinetics of RMC and PMC in Blood-Heat and Hemorrhage Syndrome Model and normal rats. The results revealed that processing and the pathological state could influence the pharmacokinetic characteristics of compounds in RMC/PMC. The study willbe useful for further studies on pharmacokinetics and clinical application of raw and processed Moutan Cortex.

[Identification of curcumin content in raw and vinegar-processed rhizomes of Curcuma kwangsiensis based on electronic nose combined with back propagation neural network].

This study aimed to establish a rapid and accurate method for identification of raw and vinegar-processed rhizomes of Curcuma kwangsiensis, in order to predict the content of curcumin compounds for scientific evaluation. A complete set of bionics recognition mode was adopted. The digital odor signal of raw and vinegar-processed rhizomes of Curcuma kwangsiensis were obtained by e-nose, and analyzed by back propagation(BP) neural network algorithm, with the accuracy, the sensitivity and specificity in discriminant model, correlation coefficient as well as the mean square error in regression model as the evaluation indexes. The experimental results showed that the three indexes of the e-nose signal discrimination model established by the neural network algorithm were 100% in training set, correction set and prediction set, which were obviously better than the traditional decision tree, naive bayes, support vector machine, K nearest neighbor and boost classification, and could accurately differentiate the raw and vinegar products. Correlation coefficient and mean square error of the regression model in prediction set were 0.974 8 and 0.117 5 respectively, and could well predict curcumin compounds content in Curcuma kwangsiensis, and demonstrate the superiority of the simulation biometrics model in the analysis of traditional Chinese medicine. By BP neural network algorithm, e-nose odor fingerprint could quickly, conveniently and accurately realize the discrimination and regression, which suggested that more bionics information acquisition and identification patterns could be combined in the field of traditional Chinese medicine, so as to provide ideas and methods for the rapid evaluation and stan-dardization of the quality of traditional Chinese medicine.

[Herbalogical study of Colla Corii Asini(Ejiao)].

Colla Corii Asini(Ejiao)is an important Chinese medicine used in China for thousands of years, and is well known for its famous tonic properties. The herbalogical study was detailed carried out based on the naming, habitat, harvesting, processing, medicinal properties and clinical efficacy. The results showed that the name of Ejiao could be traced back to Shennong's Materia Medica, and various names of Lvpi Jiao, Penfu Jiao and Fuzhi Jiao were recorded in other ancient books. In the many intervening centuries, the main materials of Ejiao had been replaced from cow leather before Tang Dynasty to donkey skin in the middle to late Tang Dynasty. This phenomenon could be probably caused by complicated social factors of various periods and different efficacy of Ejiao made by all kinds of raw materials. Ejiao was merely processed with the simple methods before Tang Dynasty, which subsequently improved avariety of methods to enhance the supplementation action. Most importantly, Ejiao has a wide clinic application along with the development of processing theories and methods, which can be found in various Classics, especially in imperial medical case record in Qing Dynasty.

A Network Pharmacology Approach Used to Estimate the Active Ingredients of Moutan Cortex Charcoal and the Potential Targets in Hemorrhagic Diseases.

Moutan Cortex charcoal has been used to ameliorate blood heat symptoms and treat pathologic hemorrhage down the ages. Although well known as an agent with the effect of astringency and hemostasis, its active ingredients and action mechanism remain unclear. In the present study, molecular docking technology was employed to screen the potential hemostatic compounds in Moutan Cortex charcoal and their target proteins. Protein-protein-interaction (PPI) analysis was performed to explain the functions and enrichment pathways of the target proteins. The results showed that a total of 25 compounds were estimated as active constituents targeting multiple proteins related to hemostatic diseases, including 5 proteins (SERPINC1, FVIII, FX, FII and FXII) that were considered as the key targets. Then the drug-target (D-T) network was constructed to analyze the underlying hemostatic mechanism of Moutan Cortex charcoal, followed by a hierarchical cluster analysis (HCA) for compounds clustering, and a coagulation screening test for compound verification on their coagulation activities, with the results indicating that M15 (5-Tetradecenoic acid) and M31 (1-Monolinolein) might be the key compounds contributing to the hemostasis effect of Moutan Cortex charcoal by involving in the pathways related to complement, coagulation cascades and the platelet activation, particularly by activating FVIII, FX, FII and FXII and inhibiting SERPINC1. This study has demonstrated that Moutan Cortex charcoal may work as a hemostatic through the interaction between multiple-compounds and multiple-proteins, which provides the basis for further researches on the hemostasis mechanism of Moutan Cortex charcoal.

Mercury-Organic Matter Interactions in Soils and Sediments: Angel or Devil?

Many studies have suggested that organic matter (OM) substantially reduces the bioavailability and risks of mercury (Hg) in soils and sediments; however, recent reports have supported that OM greatly accelerates Hg methylation and increases the risks of Hg exposure. This study aims to summarize the interactions between Hg and OM in soils and sediments and improve our understanding of the effects of OM on Hg methylation. The results show that OM characteristics, promotion of the activity of Hg-methylating microbial communities, and the microbial availability of Hg accounted for the acceleration of Hg methylation which increases the risk of Hg exposure. These three key aspects were driven by multiple factors, including the types and content of OM, Hg speciation, desorption and dissolution kinetics and environmental conditions.

[Chemical constituents in chloroform fraction of Houttuynia cordata].

Nine compounds were isolated from chloroform fraction of Houttuynia cordata,and the isolates were identified as follows:( S)-5,6,6 a,7-tetrahydro-2,10-dimethoxy-4 H-dibenzo [DE,G] quinoline-1,9-diol( 1),( +)-isoboldine ß-N-oxide( 2),liriotulipiferine( 3),telitoxinone( 4),isoboldine( 5),(-)-clovane-2ß,9α-diol( 6),benzoic acid( 7),acantrifoside E( 8),and dibutyl phthalate( 9). Among them,compound 1 was new,and compounds 2-9 were reported from this species for the first time.

Functionalized Spiroindolines with Anticancer Activity through a Metal-Free Post-Ugi Diastereoselective One-Pot Cascade Reaction.

A post-Ugi diastereoselective one-pot cascade reaction requiring no metal catalyst was developed. The reaction scope was wide with mild conditions and good yields. A collection of spiroindolines was prepared by the protocol and screening tests in several difficult-to-inhibit cancer cell lines were conducted. The relationship of structure and anticancer activities was promising and in the Huh7 cell lines compound 16 j is more potent than Vinbalstine. The cyclization design strategy could be applicable to other multicomponent reactions (MCRs) for synthesizing bioactive and drug-like heterocycles.