https://www.rsc.org/suppdata/gc/b6/b615357g/b615357g.pdf

Green synthesis of silver nanoparticles using Capsicum annuum L. extract

Biofunctional magnetic nanoparticles for protein separation and pathogen detection

In this critical review the applications of gold catalysed reactions in total synthesis during the years since our last article are reviewed. At the end of this article a literature analysis is conducted to evaluate the progress in this field.

Gold catalysis in total synthesis – recent achievements

Inorganic semiconductor nanostructures are ideal systems for exploring a large number of novel phenomena at the nanoscale and investigating the size and dimensionality dependence of their properties for potential applications. The use of such nanostructures with tailored geometries as building blocks is also expected to play crucial roles in future nanodevices. Since the discovery of carbon nanotubes much attention has been paid to exploring the usage of inorganic semiconductor nanostructures as field-emitters due to their low work functions, high aspect ratios and mechanical stabilities, and high electrical and thermal conductivities. This article provides a comprehensive review of the state-of-the-art research activities in the field. It mainly focuses on the most widely studied inorganic nanostructures, such as ZnO, ZnS, Si, WO3, AlN, SiC, and their field-emission properties. We begin with a survey of inorganic semiconductor nanostructures and the field-emission principle, and then discuss the recent progresses on several kinds of important nanostructures and their field-emission characteristics in detail and overview some additional inorganic semiconducting nanomaterials in short. Finally, we conclude this review with some perspectives and outlook on the future developments in this area.

Inorganic semiconductor nanostructures and their field-emission applications

A review on recent developments of indole-containing antiviral agents.

Plant secondary metabolites play critical roles in plant-environment interactions. They are synthesized in different organs or tissues at particular developmental stages, and in response to various environmental stimuli, both biotic and abiotic. Accordingly, corresponding genes are regulated at the transcriptional level by multiple transcription factors. Several families of transcription factors have been identified to participate in controlling the biosynthesis and accumulation of secondary metabolites. These regulators integrate internal (often developmental) and external signals, bind to corresponding cis-elements--which are often in the promoter regions--to activate or repress the expression of enzyme-coding genes, and some of them interact with other transcription factors to form a complex. In this review, we summarize recent research in these areas, with an emphasis on newly-identified transcription factors and their functions in metabolism regulation.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1744-7909.2012.01161.x

Transcriptional regulation of plant secondary metabolism

Immunity deteriorates with age in animals but comparatively little is known about the temporal regulation of plant resistance to herbivores. The phytohormone jasmonate (JA) is a key regulator of plant insect defense. Here, we show that the JA response decays progressively in Arabidopsis. We show that this decay is regulated by the miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE9 (SPL9) group of proteins, which can interact with JA ZIM-domain (JAZ) proteins, including JAZ3. As SPL9 levels gradually increase, JAZ3 accumulates and the JA response is attenuated. We provide evidence that this pathway contributes to insect resistance in young plants. Interestingly however, despite the decay in JA response, older plants are still comparatively more resistant to both the lepidopteran generalist Helicoverpa armigera and the specialist Plutella xylostella, along with increased accumulation of glucosinolates. We propose a model whereby constitutive accumulation of defense compounds plays a role in compensating for age-related JA-response attenuation during plant maturation.

/pdf/jasmonate-response-decay-and-defense-metabolite-accumulation-20kiiw0m0q.pdf

Jasmonate response decay and defense metabolite accumulation contributes to age-regulated dynamics of plant insect resistance.

Three new indole alkaloids from Trigonostemon lii.

Salvia miltiorrhiza Bunge, a perennial plant of Lamiaceae, accumulates abietane-type diterpenoids of tanshinones in root, which have been used as traditional Chinese medicine to treat neuroasthenic insomnia and cardiovascular diseases. However, to date the biosynthetic pathway of tanshinones is only partially elucidated and the mechanism for their root-specific accumulation remains unknown. To identify enzymes and transcriptional regulators involved in the biosynthesis of tanshinones, we conducted transcriptome profiling of S. miltiorrhiza root and leaf tissues using the 454 GS-FLX pyrosequencing platform, which generated 550,546 and 525,292 reads, respectively. RNA sequencing reads were assembled and clustered into 64,139 unigenes (29,883 isotigs and 34,256 singletons). NCBI non-redundant protein databases (NR) and Swiss-Prot database searches anchored 32,096 unigenes (50%) with functional annotations based on sequence similarities. Further assignments with Gene Ontology (GO) terms and KEGG biochemical pathways identified 168 unigenes referring to the terpenoid backbone biosynthesis (including 144 MEP and MVA pathway genes and 24 terpene synthases). Comparative analysis of the transcriptomes identified 2,863 unigenes that were highly expressed in roots, including those encoding enzymes of early steps of tanshinone biosynthetic pathway, such as copalyl diphosphate synthase (SmCPS), kaurene synthase-like (SmKSL) and CYP76AH1. Other differentially expressed unigenes predicted to be related to tanshinone biosynthesis fall into cytochrome P450 monooxygenases, dehydrogenases and reductases, as well as regulatory factors. In addition, 21 P450 genes were selectively confirmed by real-time PCR. Thus we have generated a large unigene dataset which provides a valuable resource for further investigation of the radix development and biosynthesis of tanshinones.

/pdf/transcriptome-analysis-of-medicinal-plant-salvia-3x2bulg7f4.pdf

Transcriptome Analysis of Medicinal Plant Salvia miltiorrhiza and Identification of Genes Related to Tanshinone Biosynthesis

α-Al2O3 Nanobelts and nanosheets with different morphologies and sizes have been successfully synthesized by a simple chemical route from H2O and Al in an argon atmosphere. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations show that the as-synthesized α-Al2O3 nanostructures consist of nanobelts and nanosheets. We find that the temperature distribution inside the alumina tube is the critical factor determining the morphologies and sizes of the α-Al2O3 nanostructures. Photoluminescence measurements showed a blue luminescence band in the wavelength range of 400–500 nm, which can be attributed to F+ centers in the α-Al2O3 nanostructures. The growth of these products is believed to be mainly determined by growth kinetics as well as thermodynamics.

Xin Fang

Papers

Transcriptional regulation of plant secondary metabolism

Jasmonate response decay and defense metabolite accumulation contributes to age-regulated dynamics of plant insect resistance.

Three new indole alkaloids from Trigonostemon lii.

Transcriptome Analysis of Medicinal Plant Salvia miltiorrhiza and Identification of Genes Related to Tanshinone Biosynthesis

Temperature-controlled growth of α-Al2O3 nanobelts and nanosheets