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61.
62.
Hyejin Hyeon Ho Bong Hyun Boram Go Sung Chun Kim Yong-Hwan Jung Young-Min Ham 《Molecules (Basel, Switzerland)》2022,27(1)
Magnolia flower buds are a source of herbal medicines with various active compounds. In this study, differences in the distribution and abundance of major essential oils, phenolic acids, and primary metabolites between white flower buds of Magnolia heptapeta and violet flower buds of Magnolia denudata var. purpurascens were characterised. A multivariate analysis revealed clear separation between the white and violet flower buds with respect to primary and secondary metabolites closely related to metabolic systems. White flower buds contained large amounts of monoterpene hydrocarbons (MH), phenolic acids, aromatic amino acids, and monosaccharides, related to the production of isoprenes, as MH precursors, and the activity of MH synthase. However, concentrations of β-myrcene, a major MH compound, were higher in violet flower buds than in white flower buds, possibly due to higher threonine levels and low acidic conditions induced by comparatively low levels of some organic acids. Moreover, levels of stress-related metabolites, such as oxygenated monoterpenes, proline, and glutamic acid, were higher in violet flower buds than in white flower buds. Our results support the feasibility of metabolic profiling for the identification of phytochemical differences and improve our understanding of the correlated biological pathways for primary and secondary metabolites. 相似文献
63.
Gopal Lamichhane Prakash Raj Pandeya Ramakanta Lamichhane Su-jin Rhee Hari Prasad Devkota Hyun-Ju Jung 《Molecules (Basel, Switzerland)》2022,27(3)
Background: Ponciri Fructus, a crude drug consisting of the dried immature fruits of Poncirus trifoliata (L.) Raf., is a popular folk medicine used for the treatment of allergy and gastrointestinal disorders in Korea and China. In this study, the anti-adipogenic activity of extracts and isolated compounds were evaluated using 3T3-L1 preadipocytes. Methods: Dried immature fruits were extracted and fractionated into n-hexane, ethyl acetate (EtOAc), n-butanol and water-soluble fractions. The ethanol extract and fractions were tested for anti-adipogenic activity in the 3T3-L1 cell line. The active fractions (n-hexane and EtOAc fractions) were further subjected to chromatographic techniques to isolate and identify active compounds. Furthermore, the isolated compounds were evaluated for their anti-adipogenic activity. Results: Altogether, seven compounds, including two flavonoids, one phytosteroid and four coumarin derivatives, were isolated. Ethanol extract, n-hexane fraction, EtOAc fraction and three isolated compounds (phellopterin, oxypeucedanin and poncirin) showed significant anti-adipogenic activity as observed by reduced lipid deposition in differentiated 3T3-L1 cells. Further, oxypeucedanin downregulated the key adipogenic markers, such as peroxisome proliferator-activated receptors proteins γ (PPAR-γ), sterol response element binding proteins-1 (SREBP-1), CCAAT/enhancer binding proteins-α (C/EBP-α), adipocyte-specific lipid binding proteins (FABP-4), adipocyte fatty acid binding proteins (aP2), lipoprotein lipase (LPL) and leptin. Conclusion: This study indicated that the ethanol extract, hexane fraction and ethyl acetate fraction of P. trifoliata fruits possess strong anti-adipogenic activity, containing the active compounds such as phellopterin, oxypeucedanin and poncirin. Further research is recommended to explore their efficacy and safety in animal and clinical models. 相似文献
64.
65.
Hue Thi Buu Bui Phuong Hong Nguyen Quan Minh Pham Hoa Phuong Tran De Quang Tran Hosun Jung Quang Vinh Hong Quoc Cuong Nguyen Quy Phu Nguyen Hieu Trong Le Su-Geun Yang 《Molecules (Basel, Switzerland)》2022,27(7)
Epigenetic alterations found in all human cancers are promising targets for anticancer therapy. In this sense, histone deacetylase inhibitors (HDACIs) are interesting anticancer agents that play an important role in the epigenetic regulation of cancer cells. Here, we report 15 novel hydroxamic acid-based histone deacetylase inhibitors with quinazolinone core structures. Five compounds exhibited antiproliferative activity with IC50 values of 3.4–37.8 µM. Compound 8 with a 2-mercaptoquinazolinone cap moiety displayed the highest antiproliferative efficacy against MCF-7 cells. For the HDAC6 target selectivity study, compound 8 displayed an IC50 value of 2.3 µM, which is 29.3 times higher than those of HDAC3, HDAC4, HDAC8, and HDAC11. Western blot assay proved that compound 8 strongly inhibited tubulin acetylation, a substrate of HDAC6. Compound 8 also displayed stronger inhibition activity against HDAC11 than the control drug Belinostat. The inhibitory mechanism of action of compound 8 on HDAC enzymes was then explored using molecular docking study. The data revealed a high binding affinity (−7.92 kcal/mol) of compound 8 toward HDAC6. In addition, dock pose analysis also proved that compound 8 might serve as a potent inhibitor of HDAC11. 相似文献
66.
Miji Yeom Hyanggi Ji Jongheon Shin Eunae Cho De-Hun Ryu Deokhoon Park Eunsun Jung 《Molecules (Basel, Switzerland)》2022,27(4)
Striae distensae (SD) or stretch marks are common linear scars of atrophic skin with disintegrating extracellular matrix (ECM) structures. Although fibroblasts contribute to the construction of ECM structure in SD, some studies have reported that mast cell degranulation causes the disruption of ECM in early SD lesions. Lagerstroemia indica flower (LIF) has traditionally been used in India as a diuretic. However, little is known about the effect and molecular action of Lagerstroemia indica flower extract (LIFE) on alleviating SD. This study evaluated the effects of LIFE on mast cell degranulation and the synthesis of ECM components in fibroblasts. LIFE inhibits the adhesion of rat basophilic leukemia (RBL) cells, RBL-2H3 on fibronectin (FN) and the expression of integrin, a receptor for FN, thereby reducing focal adhesion kinase (FAK) phosphorylation. In addition, LIFE attenuated the allergen-induced granules and cytokine interleukin 3 (IL-3) through the adhesion with FN. Moreover, the conditioned medium (CM) of activated mast cells decreases the synthesis of ECM components, and LIFE restores the abnormal expressions induced by activated mast cells. These results demonstrate that LIFE suppresses FN-induced mast cell activation and promotes the synthesis of ECM components in fibroblast, which indicates that LIFE may be a useful cosmetic agent for SD treatment. 相似文献
67.
Seokwoo Kang Hayoon Lee Hyocheol Jung Donghee Shin Miyeon Park 《Molecular Crystals and Liquid Crystals》2018,662(1):96-101
ABSTRACTTIACA-I, TIACA-II were synthesized by changing the substitution position of the imidazole group in the diazocine core. TIACA-I, TIACA-II in the film state showed absorption in the range of 354 to 392 nm and exhibited blue photoluminescence (PL) emissions at 448 and 462 nm, respectively. The PL wavelength of TIACA-II is red-shifted by 14 nm than that of TIACA-I due to the electron-donating intensity depending on the position of the imidazole group. The use of TIACA-II in a non-doped OLED device resulted in blue emission with current efficiency of 2.84 cd/A and CIE of (0.15, 0.18). 相似文献
68.
Jung A. Jung Young Baek Kim Young A. Kim Seung Bum Ryu Veronica Kim 《Journal of nanoparticle research》2011,13(6):2361-2374
Functional spherical solid and hollow particles of polysilsesquioxanes (PSQs) containing amine, thiol, and vinyl groups were
prepared by polymerizing organotrialkoxysilanes (OTASs) containing corresponding chemical groups. Fluorescent PSQ particles
were prepared by physically entrapping Rhodamine 6G, Coumarin 7, and Fluoresceine sodium salts. The intensity of fluorescent
light increased initially with increasing amount of entrapped fluorophores and then leveled off or decreased slightly after
reaching a maximum value. PSQ particles containing gold nanoparticles (GNPs), both inside and on the surface, were prepared
by the in situ reduction of gold ions by the PSQ particles. When the reduction reaction was carried out for extended periods
of time, the GNP that had formed inside the poly(3-mercaptopropyl)silsesquioxane (PMPSQ) and polyvinylsilsesequioxane (PVSQ)
particles underwent interesting morphological changes. PSQ particles containing amine and thiol groups fixed the GNPs on the
surface, which could be utilized further in binding amine-modified oligo-DNA strands. The aggregation of PSQ/GNP particles
combined with complementary oligo-DNA strands was examined to demonstrate that these particles could be applied to DNA assays
and isolation. The particles were characterized by scanning electron microscopy, transmission electron microscopy, solid state
nuclear magnetic resonance spectroscopy, ultraviolet/visible spectroscopy, and fluorescence microscopy. 相似文献
69.
D.S. Jung S.K. Hong J.S. Cho Y.C. Kang 《Applied Physics A: Materials Science & Processing》2007,89(3):769-774
Fine-sized BaO-ZnO-B2O3-SiO2 (BZBS) glass powders were directly prepared by high temperature spray pyrolysis. The hollow glass powders prepared at low
preparation temperature of 1000 °C had a low density of 2.65 g/cm3. However, the densities of the BZBS powders obtained at preparation temperatures of 1200 and 1400 °C were each 3.92 and 4.13 g/cm3. The mean size of the BZBS glass powders prepared by spray pyrolysis at preparation temperature of 1400 °C was 0.98 μm. The
glass transition temperature (Tg) of the prepared BZBS glass powders was 518.9 °C. The dielectric layers formed from the prepared BZBS glass powders with
a dense structure had a clean surface and a dense inner structure without voids at the firing temperature of 580 °C. The transparencies
of the dielectric layers formed from the prepared BZBS glass powders were higher than 90% within the visible range.
PACS 42.70.Ce; 85.60.Pg; 71.55.Jv 相似文献
70.
The perovskite-type Ba- and Ti/Nb-doped (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) oxides were synthesized successfully by the solid-state reaction method. Crystal structure, elemental compositions, and oxygen nonstoichiometry of the as-synthesized (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) oxides were investigated by X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), inductively coupled plasma (ICP)-atomic emission spectrometry, thermogravimetry (TG), and iodometric titration. XRD results demonstrate that the as-obtained (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) oxides possess purely cubic perovskite-type structures. The temperature-swing oxygen sorption/desorption properties of the as-synthesized (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) perovskite-type oxides were studied by the dynamic TG. Results show that the structural stability of the co-doped (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) oxides is improved greatly, and the high oxygen sorption capacity for the perovskite-type (Ba0.15Sr0.85)(B0.15Co0.85)O3 ? δ (B = Ti, Nb) oxides is also obtained between 300 and 950 °C in air. 相似文献