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1.
Nat Commun ; 15(1): 525, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225267

RESUMO

Transport of rodlike particles in confinement environments of macromolecular networks plays crucial roles in many important biological processes and technological applications. The relevant understanding has been limited to thin rods with diameter much smaller than network mesh size, although the opposite case, of which the dynamical behaviors and underlying physical mechanisms remain unclear, is ubiquitous. Here, we solve this issue by combining experiments, simulations and theory. We find a nonmonotonic dependence of translational diffusion on rod length, characterized by length commensuration-governed unconventionally fast dynamics which is in striking contrast to the monotonic dependence for thin rods. Our results clarify that such a fast diffusion of thick rods with length of integral multiple of mesh size follows sliding dynamics and demonstrate it to be anomalous yet Brownian. Moreover, good agreement between theoretical analysis and simulations corroborates that the sliding dynamics is an intermediate regime between hopping and Brownian dynamics, and provides a mechanistic interpretation based on the rod-length dependent entropic free energy barrier. The findings yield a principle, that is, length commensuration, for optimal design of rodlike particles with highly efficient transport in confined environments of macromolecular networks, and might enrich the physics of the diffusion dynamics in heterogeneous media.

2.
Food Chem ; 429: 136821, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37478599

RESUMO

Blue honeysuckle (Lonicera caerulea L.) berries are nutritionally rich and unique in flavor. However, its aroma compounds have not been known well. In this study, the key aroma-active compounds in 8 different varieties of blue honeysuckle berries were studied by sensory-directed analysis. Sensory evaluation suggested that the aroma profile of blue honeysuckle berry was fruity, floral, grassy, sweet, and sour. A total of 68 aroma compounds were detected by two-dimensional comprehensive gas chromatography-olfactometry-mass spectrometry analysis (GC × GC-O-MS). Then, aroma extraction dilution analysis (AEDA) and odor activity value (OAV) showed that 12 compounds were indicated to be the major aroma contributors. According to the principal component analysis (PCA) results, eight varieties were divided into three categories for their differences on alcohols and terpenoids content. Finally, the aroma recombination and omission experiments determined that linalool, hexanal, eucalyptol, octanal, nonanal, and ethyl 2-methylbutyrate were the key aroma-active compounds in blue honeysuckle berries.


Assuntos
Lonicera , Compostos Orgânicos Voláteis , Odorantes/análise , Frutas/química , Olfatometria/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise
3.
J Pharm Biomed Anal ; 161: 455-463, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30216794

RESUMO

Gentianopsis barbata, Halenia corniculata, and Gentianella acuta were widely distributed throughout China and commonly used in traditional Chinese medicine. However, owing to similar living environments and morphological features, locals often had trouble distinguishing between these three species. In this present study, chromatograms at 350 nm were obtained and the composition and content of their chemical compounds determined using HPLC-DAD/ESI-MS2. In total, 35 chemical compounds were detected, 32 of which were identified, 25 of which were xanthones, 6 flavonoids, and 1 chlorogenic acid. The 350 nm chromatograms of these three species displayed evident differences. The individual compounds and their occurrence and content in different parts of the plant within different species were included in our results. This basic data will be useful for future pharmacological study. The total compositions of flavonoids and xanthones were approximately comparable in G. barbata and H. corniculata. Meanwhile, xanthones were predominant in G. acuta. From the perspective of chemical compound compositions, the leaf is recommended as the most valuable medicinal section for each of these three species.


Assuntos
Ácido Clorogênico/análise , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Gentianaceae/química , Xantonas/análise , Cromatografia Líquida de Alta Pressão , Estruturas Vegetais/química , Espectrometria de Massas por Ionização por Electrospray
4.
Food Chem ; 204: 150-158, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26988488

RESUMO

Various edible berries widely accessible in nature in Northeast China are poorly exploited. The compositions and contents of anthocyanins in black (Padus maackii, Padus avium, Lonicera caerulea, and Ribes nigrum) and red (Ribes rubrum, Sambucus williamsii, Rubus idaeus, and Ribes procumbens) wild berries in Northeast China were firstly characterized by HPLC-DAD/ESI-MS(2). Twenty-three anthocyanins were detected and identified. Cyanidin glycosides were dominant in both berries. Six anthocyanins were reported for the first time in P. avium, R. rubrum, and Sambucus. Total anthocyanin content (TAC) ranged from 10mg/100gfreshweight (FW) (R. procumbens) to 1058mg/100gFW (P. maackii) among berries. The TACs and antioxidant activities assessed by DPPH and FRAP assays were much higher in black than in red berries. Black-red berries, especially P. maackii and P. avium, can be used in developing functional foods and in improving breeding programs.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Frutas/química , Pigmentos Biológicos/análise , Ribes/química , Rosaceae/química , Antocianinas/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo/química , China , Frutas/crescimento & desenvolvimento , Lonicera/química , Lonicera/crescimento & desenvolvimento , Espectrometria de Massas , Picratos/química , Pigmentos Biológicos/farmacologia , Ribes/crescimento & desenvolvimento , Rosaceae/crescimento & desenvolvimento , Sambucus/química , Sambucus/crescimento & desenvolvimento , Especificidade da Espécie
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