Structures and formation pathways of compounds responsible for pink discoloration of onion and leek were studied. A procedure was developed for the isolation and purification of the color compounds from various model systems and their identification by HPLC-DAD-MS/MS. In total, structures of 15 major color compounds were tentatively determined. It was found that the pigment is a complex mixture of highly conjugated species composed of two N-substituted 3,4-dimethylpyrrole-derived rings linked by either a methine or a propenylidine bridge. These two-ring units are further modified by various C1- and C3-side chains. Experiments with isotope-labeled thiosulfinates revealed that the methine bridge and C1-side chains originate from the methyl group of methiin, whereas the C3 units are derived from the propenyl group of isoalliin.
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http://dx.doi.org/10.1021/acs.jafc.5b04564 | DOI Listing |
J Am Chem Soc
January 2025
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
The development of stable and tunable polycyclic aromatic compounds (PACs) is crucial for the advancement of organic optoelectronics. Conventional PACs, such as acenes, often suffer from poor stability due to photooxidation and oligomerization, which are linked to their frontier molecular orbital energy levels. To address these limitations, we designed and synthesized a new class of π-expanded indoloindolizines by merging indole and indolizine moieties into a single polycyclic framework.
View Article and Find Full Text PDFFor Res (Fayettev)
December 2024
State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China.
Polyphenols, as one of the primary compounds produced by plant secondary metabolism, have garnered considerable attention because of their non-toxic, environmentally friendly, and biodegradable properties, as well as their notable medicinal value. This study presents a metabolomic analysis of polyphenols from 11 woody plants, including , , and , investigating a total of 40 polyphenolic metabolites. A differential metabolite dynamics map highlighted the five most differentiated substances among the 11 plants, including vitexin, dihydromyricetin, genistin, resveratrol, and isorhamnetin.
View Article and Find Full Text PDFNanoscale
January 2025
Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, No. 2 ZhongGuanCun BeiYiJie, 100190, Beijing, P. R. China.
In recent years, the regulation of anion-mediated chiral assemblies has gained significant interest. This study investigated the modulation of supramolecular chiroptical signals and chiral assembled structures in a triarylamine system containing a urea moiety through fluoride ion-urea bond interactions, aiming to understand the chiral sense amplification in supramolecular assemblies. Chiral triarylamine derivatives containing urea or amide units were synthesized and the self-assemblies were examined in the absence and presence of fluoride ions.
View Article and Find Full Text PDFJ Texture Stud
February 2025
Department of Mathematics, Aditya University, Surampalem, Andhra Pradesh, India.
This study investigated the impacts of hot water treatment (HWT) at 50°C or 25°C for 5 min and high-temperature ethylene (HTE) exposure at varying temperatures (20°C, 30°C, or 35°C) and durations (24, 48, or 72 h) on the postharvest quality and antioxidant properties of mature green tomatoes (MG). Color changes, physicochemical characteristics, antioxidant compounds, and overall antioxidant ability were assessed. HWT increased β-carotene levels and oxygen radical absorbance capacity (ORAC) while preserving color metrics, despite later HTE exposure.
View Article and Find Full Text PDFBMC Genom Data
January 2025
Institute of Biotechnology and Food Science, Hebei Academy of Agriculture and Forestry Sciences/Hebei Key Laboratory of Plant Genetic Engineering, Shijiazhuang, 050000, China.
Background: Wheat seeds display different colors due to the types and contents of anthocyanins, which is closely related to anthocyanin metabolism. In this study, a transcriptomic and metabolomic analysis between white and purple color wheat pericarp aimed to explore some key genes and metabolites involved in anthocyanin metabolism.
Results: Two wheat cultivars, a white seed cultivar Shiluan02-1 and purple seed cultivar Hengzi151 were used to identify the variations in differentially expressed genes (DEGs) and differentially accumulated flavonoids (DAFs).
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