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91.
The objectives of this study were to produce sodium alginate (SA)-based cryogel beads filled with different concentrations (0, 0.4, 1.0, and 2.5%, w/w) of hydroxypropyl distarch phosphate (HDP) as a curcumin delivery system and to investigate the physicochemical, structural, and in vitro gastrointestinal tract release properties of the cryogel beads. According to FT-IR analysis, the formation of ionic crosslinking between SA and Ca2+ and the presence of HDP were found. XRD analysis demonstrated the successful encapsulation of curcumin in the beads by observing the disappearance of the characteristic peaks of curcumin. SEM analysis results revelated that SA-based cryogel beads exhibited a denser internal structure as the HDP concentration was increased. The encapsulation efficiency of curcumin in SA cryogel beads filled with HDP concentration from 0% to 2.5% was increased from 31.95% to 76.66%, respectively, indicating that HDP can be a suitable filler for the encapsulation of curcumin in the production of SA-based cryogel beads. After exposure to simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), the release rate of curcumin was decreased as HDP concentration was increased. Accordingly, SA-based cryogel beads filled with HDP can be utilized for the delivery system of curcumin in the food industry. 相似文献
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Byungju Kim Jincheol Seol Yoon Ki Kim Jong-Bong Lee 《Experimental & molecular medicine》2023,55(2):283
Translation is mediated by precisely orchestrated sequential interactions among translation initiation components, mRNA, and ribosomes. Biochemical, structural, and genetic techniques have revealed the fundamental mechanism that determines what occurs and when, where and in what order. Most mRNAs are circularized via the eIF4E–eIF4G–PABP interaction, which stabilizes mRNAs and enhances translation by recycling ribosomes. However, studies using single-molecule fluorescence imaging have allowed for the visualization of complex data that opposes the traditional “functional circularization” theory. Here, we briefly introduce single-molecule techniques applied to studies on mRNA circularization and describe the results of in vitro and live-cell imaging. Finally, we discuss relevant insights and questions gained from single-molecule research related to translation.Subject terms: Single-molecule biophysics, Ribosome 相似文献
93.
Suji Lee Ryeong Ha Kwon Ju Hyung Kim Hyemin Na So-Jeong Lee Yu-Mi Choi Hyemyeong Yoon So Young Kim Yong-Suk Kim Sang Hoon Lee Seon Mi Yoo Heon-Woong Kim Chi-Do Wee 《Molecules (Basel, Switzerland)》2022,27(13)
In this study, thirty-eight isoflavone derivatives were comprehensively identified and quantified from the raw, steamed and fermented seeds of four selected soybean cultivars based on UPLC-DAD-QToF/MS results with reference to the previously reported LC-MS library and flavonoid database, and summarized by acylated group including glucosides (Glu), malonyl-glucosides (Mal-Glu), acetyl-glucosides (Ac-Glu), succinyl-glucosides (Suc-Glu) and phosphorylated conjugates (Phos) in addition to aglycones. Among them, Suc-Glu and Phos derivatives were newly generated due to fermentation by B. subtilis AFY-2 (cheonggukjang). In particular, Phos were characterized for the first time in fermented soy products using Bacillus species. From a proposed roadmap on isoflavone-based biotransformation, predominant Mal-Glu (77.5–84.2%, raw) decreased rapidly by decarboxylation and deesterification into Ac-Glu and Glu (3.5–8.1% and 50.0–72.2%) during steaming, respectively. As fermentation continued, the increased Glu were mainly succinylated and phosphorylated as well as gradually hydrolyzed into their corresponding aglycones. Thus, Suc-Glu and Phos (17.3–22.4% and 1.5–5.4%, 36 h) determined depending on cultivar type and incubation time, and can be considered as important biomarkers generated during cheonggukjang fermentation. Additionally, the changes of isoflavone profile can be used as a fundamental report in applied microbial science as well as bioavailability research from fermented soy foods. 相似文献
94.
Wongi Park Minyong Yang Hyewon Park Dr. Joanna M. Wolska Dr. Hyungju Ahn Prof. Dr. Tae Joo Shin Prof. Dr. Damian Pociecha Prof. Dr. Ewa Gorecka Prof. Dr. Dong Ki Yoon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(24):7108-7113
Herein, it is reported that the polymorphism in the helical nanofilament (HNF, B4) liquid-crystalline phase depends on the fabrication methods, that is, UV-driven formation and template-assisted self-assembly in the nanoconfined geometry. As a result, uniaxially oriented HNFs with different helical structures were obtained, in which generation of the twisted-ribbon and cylindrical-ribbon polymorphs showed that even the molecular lattice has a different orientation. The detailed structures were directly observed by SEM and grazing-incidence X-ray diffraction with synchrotron radiation. The resultant polymorphs could be used in chiro-optical applications due to the capability for fine control of the helical structures. 相似文献
95.
Journal of Radioanalytical and Nuclear Chemistry - Tritium and stable isotopes contents in precipitation were analyzed on a monthly base at Hongseung which was located middle west of Korea... 相似文献
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