Simultaneous Analysis of Six Polymethoxyflavones and Six 5‑Hydroxy-polymethoxyflavones by High Performance Liquid Chromatography Combined with Linear Ion Trap Mass Spectrometry

Polymethoxyflavones (PMFs) and monohydroxylated polymethoxyflavones (OH-PMFs) exist exclusively in the citrus genus, particularly in citrus peels. Currently, due to the broad application of PMFs and OH-PMFs in nutraceuticals, pharmaceuticals, and functional foods, their identification and quantification will be of great significance and the first criteria to meet. We have developed a validated method with high performance liquid chromatography coupled with linear ion trap mass spectrometry. The method was fully validated in linearity, precision, accuracy, and recovery. Six PMFs and their monohydroxyl counterparts, six 5-OH-PMFs, were simultaneous analyzed within 20 min for the first time. The LOD (limit of detection) and LOQ (limit of quantitation) were calculated as 0.02–0.23 and 0.05–0.76 μg/mL, respectively. The method was performed on the samples of acid treated citrus peel extracts. The citrus peel extracts with high content of PMFs and 5-OH PMFs may provide reliable and economical resources in biological activity studies and development of health beneficial products

An All-Photonic Molecule-Based D Flip-Flop

The photochromic fluorescence switching of a fulgimide derivative was used to implement the first molecule-based D (<i>delay</i>) flip-flop device, which works based on the principles of sequential logic. The device operates exclusively with photonic signals and can be conveniently switched in repeated cycles

An All-Photonic Molecule-Based Parity Generator/Checker for Error Detection in Data Transmission

The function of a parity generator/checker, which is an essential operation for detecting errors in data transmission, has been realized with multiphotochromic switches by taking advantage of a neuron-like fluorescence response and reversible light-induced transformations between the implicated isomers

Characterization of the Thermal and Photoinduced Reactions of Photochromic Spiropyrans in Aqueous Solution

Six water-soluble spiropyran derivatives have been characterized with respect to the thermal and photoinduced reactions over a broad pH-interval. A comprehensive kinetic model was formulated including the spiro- and the merocyanine isomers, the respective protonated forms, and the hydrolysis products. The experimental studies on the hydrolysis reaction mechanism were supplemented by calculations using quantum mechanical (QM) models employing density functional theory. The results show that (1) the substitution pattern dramatically influences the p<i>K</i>_a-values of the protonated forms as well as the rates of the thermal isomerization reactions, (2) water is the nucleophile in the hydrolysis reaction around neutral pH, (3) the phenolate oxygen of the merocyanine form plays a key role in the hydrolysis reaction. Hence, the nonprotonated merocyanine isomer is susceptible to hydrolysis, whereas the corresponding protonated form is stable toward hydrolytic degradation

Distribution of lengths of the assembled unigenes in wheat pericarps.

<p>Distribution of lengths of the assembled unigenes in wheat pericarps.</p

The expression differences of structural genes in the phenylalanine pathway.

<p>Arrow shows the metabolic stream, abbreviation left or upward arrows represent the genes catalyzing the progress, the light abbreviation means these genes were found in assembly unigenes, the number represent the in crease time of the expression in purple pericarp against white pericarp.</p

The length of unigenes in Gy115 and reference genes relative to flavonoids biosynthesis.

<p>The length of unigenes in Gy115 and reference genes relative to flavonoids biosynthesis.</p

Summary statistics of functional annotation for unigenes.

<p>Summary statistics of functional annotation for unigenes.</p

Gene Ontology (GO) classifications of differentially expressed unigenes.

<p>Unigenes were assigned to three categories: cellular components, molecular functions and biological process.</p

Transcriptome Analysis of Purple Pericarps in Common Wheat (<i>Triticum aestivum</i> L.)

<div><p>Wheat (<i>Triticum aestivum</i> L.) cultivars possessing purple grain arethought to be more nutritious because of high anthocyanin contents in the pericarp. Comparative transcriptome analysis of purple (cv Gy115) and white pericarps was carried out using next-generation sequencing technology. There were 23,642 unigenes significantly differentially expressed in the purple and white pericarps, including 9945 up-regulated and 13,697 down-regulated. The differentially expressed unigenes were mainly involved in encoding components of metabolic pathways, The flavonoid biosynthesis pathway was the most represented in metabolic pathways. In the transcriptome of purple pericarp in Gy115, most structural and regulatory genes biosynthesizing anthocyanin were identified, and had higher expression levels than in white pericarp. The largestunigene of anthocyanin biosynthesis in Gy115 was longer than the reference genes, which implies that high-throughput sequencing could isolate the genes of anthocyanin biosynthesis in tissues or organs with high anthocyanin content. Based on present and previous results, three unigenes of <i>MYB</i> gene on chromosome 7BL and three unigenes of <i>MYC</i> on chromosome 2AL were predicted as candidate genes for the purple grain trait. This article was the first to provide a systematic overview comparing the transcriptomes of purple and white pericarps in common wheat, which should be very valuable for identifying the key genes for the purple pericarp trait.</p></div