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[Display omitted] • A facile co-precipitation method is used to prepare catalysts with particles confined in cheap MOF. After calcination, more catalytic active sites could be exposed, which greatly improves the performance of the catalyst. • Compared with other methods, the co-precipitation method is simple, low-cost, and can better control the metal loading. At the same time, the problem of easy agglomeration of Cu nanoparticles and easy phase separation of Cu and ZnO at high temperature could be alleviated greatly. • The as-prepared Cu/ZnO x /ZrO 2 catalyst shows much better performance for CO 2 hydrogenation to methanol than the commercialized catalyst and catalyst prepared by double solvents method. The ternary Cu/ZnO/Al 2 O 3 catalyst is usually employed for producing methanol from syngas (CO/CO 2 /H 2) or from CO 2 hydrogenation in industry. However, this catalyst often suffers from the aggregation of Cu nanoparticles and the phase separation of Cu and ZnO. In this work, a highly efficient and stable catalyst (Cu/ZnO x /ZrO 2) for CO 2 hydrogenation to methanol is prepared via co-precipitation method with UiO-66 as structural template. Cu/Zn is effectively combined and encapsulated in the channels of UiO-66, which avoids the aggregation of metal particles. The ZrO 2 support derived from UiO-66 enhances the interaction between the support and Cu/Zn, and thus improves the catalytic performance significantly. This catalyst shows a high space–time yield of 216.7 g (MeOH) ·kg (cat) −1·h−1 at 260 °C, 4 MPa and GHSV = 12000 h−1. Furthermore, the catalyst shows good stability over a period of 50 h on stream. The performance of Cu/ZnO x /ZrO 2 is much better than that of commercial catalysts and most of catalysts previously reported. [ABSTRACT FROM AUTHOR]

The accumulation of heavy metal on catalysts during petrochemical process produces deactivated catalysts that cannot be directly disposed in nature, due to the high toxicity. The elimination of the detrimental effect of heavy metal ions can be achieved by immobilizing these ions in the form of spinel structure, yet this requires high-temperature calcination. Herein, Ni2+ ions are stabilized and confined within the surface NiAl 2 O 4 on Al 2 O 3 through hydrothermal process and subsequent low-temperature thermal treatment. The formation of nickel aluminum layered double hydroxide (NiAl-LDH) as intermediate favors the generation of surface aluminate spinel at the temperature as low as 450 ​°C. The formation of surface spinel is beneficial to restricting the mobility of Ni2+ ions. The growth and immobilization mechanisms of the surface spinel structure were proposed, which contributes to alternative and promising route for the low-temperature approach of the retention of the heavy metal ions mobility. Heavy metal Ni2+ ions are stabilized and confined within the surface NiAl 2 O 4 on Al 2 O 3 through hydrothermal process and subsequent low-temperature thermal treatment. [Display omitted] • The stabilization of Ni2+ ions is achieved by the surface NiAl 2 O 4 on Al 2 O 3. • NiAl-LDH facilities the presence of surface NiAl 2 O 4 at 450 ​°C. • The process of low-temperature nickel stabilization is discussed. • The surface amount of NiAl 2 O 4 reaches equilibrium above 450 ​°C. • The confined sample exhibited superior immobilization behavior of Ni2+ ions. [ABSTRACT FROM AUTHOR]

Microbially induced calcium precipitation (MICP) driven by denitrification has attracted extensive attention due to its application potential in nitrate removal from calcium-rich groundwater. However, little research has been conducted on this technique at the molecular level. Here, Pseudomonas WZ39 was used to explore the molecular mechanisms of nitrate-dependent MICP and the effects of Ca2+ on bacterial transcriptional regulation and metabolic response. The results exhibited that appropriate Ca2+ concentration (4.5 mM) can promote denitrification and the production of ATP, EPSs, and SMPs. Genome-wide analysis showed that the nitrate-dependent MICP was accomplished through heterotrophic denitrification and CO 2 capture. During this process, EPS biosynthesis and Ca2+ signaling regulation were involved in the nucleation template supply and Ca2+ homeostasis balance. Untargeted transcriptome- and metabolome-association analyses revealed that the addition of Ca2+ triggered the significant up-regulation in several key pathways, such as transmembrane transporter and channel activities, amino acid metabolism, fatty acid biosynthesis, and carbon metabolism, which played a momentous role in the mineral nucleation and energy provision. The detailed information provided novel insights for understanding the active control of bacteria on MICP, and has great significance for deepening the cognition of groundwater remediation using nitrate-dependent MICP technique. [Display omitted] • Nitrate-dependent MICP were first studied from multi-omics perspective. • Appropriate Ca2+ promoted denitrification and production of ATP, EPSs, and SMPs. • Metabolic pathways of strain WZ39 were revealed using genome-wide sequencing. • The up-regulation of EPS and fatty acid synthesis offered more sites for nucleation. • Carbon metabolism, and transport and channel activities played vital roles in MICP. [ABSTRACT FROM AUTHOR]

Japanese apricot is an imperative stone fruit plant with numerous processing importance. The failure of reproductive system is the most common cause of fruit loss, through which pistil abortion is the fundamental one. To understand this mechanism, we used a combination of transcriptomic and metabolomic approaches to investigate the biochemical and molecular basis of flavonoid biosynthesis. Due to the regulated expression of flavonoid pathway-related genes in plants, flavonoid biosynthesis is largely regulated at the transcriptional level. A total of 2272 differently expressed genes and 215 differential metabolites were found. The expression of the genes and metabolites encoding flavonoid biosynthesis was lower in abnormal pistils that are in line with the flavonoid quantification from abnormal pistils. Besides, a couple of genes were also detected related to MYB, MADS, NAC and bHLH transcription factors. Remarkably, we found 'hydroxycinnamoyl transferase (LOC103323133)' and flavonoid related metabolite '2-hydroxycinnamic acid' was lower expressed in abnormal pistil, proposing the cause of pistil abortion. Collectively, the present study delivers inclusive transcriptional and metabolic datasets that proposed valuable prospects to unravel the genetic mechanism underlying pistil abortion. [Display omitted] • The biochemical and molecular basis of flavonoid biosynthesis is studied using transcriptomic and metabolomics approaches • The expression of the genes and metabolites encoding flavonoid biosynthesis was lower in abnormal pistils • "Hydroxycinnamoyl transferase' and '2-hydroxycinnamic acid' was lower expressed might be the cause of pistil abortion [ABSTRACT FROM AUTHOR]

Mineral nutrition is the material basis for growth and quality improvement of fruit trees. In this study, artificial neural networks (ANNs) and Multiple linear regression (MLR) models were used to study the influence of mineral nutrient elements in fruits on the peach fruit quality. The results showed that four established ANN models of the fruit quality with the Log-sigmoid transfer function and the Levenberg-Marquardt back-propagation training function can obtain the highest accuracy (R2 =0.9243, 0.9260, 0.9536, and 0.9644 respectively). The results of the sensitivity and redundancy analysis indicated that the nitrogen, phosphorus, potassium, magnesium, and iron content in fruits had the greatest contribution to these fruit quality indicators of the peach, which was of great significance to the fertilization of peach orchards and the improvement of peach fruit quality. • The effects of mineral elements in fruits on the peach fruit quality were studied. • Four effective ANN models were established to predict the peach fruit quality. • The N, P, K, Mg, and Fe content had significant effects on peach fruit quality. [ABSTRACT FROM AUTHOR]

Variegation in flower is a special trait in ornamental peach ( Prunus persica L.). To investigate the mechanism of color variegation, we used a combination of two dimensional gel electrophoresis and mass spectrometry to explore the proteomic profiles between variegated flower (VF) and red flower (RF) buds of the peach cultivar ‘Sahong Tao’. More than 500 highly reproducible protein spots (P < 0.05) were detected and 72 protein spots showed a greater than two-fold difference in their values. We identified 70 proteins that may play roles in petal coloration. The mRNA levels of the corresponding genes were detected using quantitative RT-PCR. The results show that most of the proteins are involved in energy and metabolism, which provide energy and substrates. We found that LDOX, WD40, ACC, and PPO II are related to the pigment biosynthetic pathway. The activity of PPO enzyme was further validated and showed the higher with significant differences in RF compared with the VF ones. Moreover, the four UCH proteins are involved in protein fate and may be important in post-translational modifications in peach flowers. Our study is the first comparative proteomic analysis of floral variegation and will contribute to further investigations into the molecular mechanism of flower petal coloration in ornamental peach. [ABSTRACT FROM AUTHOR]

Abstract: Antimicrobial peptides (AMPs) are a group of immune proteins that protect the host from infection. In Drosophila, seven groups of inducible AMPs have been identified, with activities against fungi and gram-positive and gram-negative bacteria. On the basis of the silkworm genome sequence and expressed sequence tags, we identified 35 AMP genes, mostly belonging to the cecropin, moricin, and gloverin gene families. We predicted the core promoters required for gene transcription and the cis-regulatory elements for NF-κB/Rel and GATA transcription factors. The expression profiles of these genes after an immune challenge with lipopolysaccharide were examined by reverse transcription PCR. Members of the cecropin B and gloverin A subfamilies were intensely expressed in the fat body after induction. In contrast, those of the moricin B subfamily were not expressed under the same conditions. Such results suggest that these regulatory elements and their positions in the upstream regions play an important role in regulating the transcription of these defense genes. [Copyright &y& Elsevier]