Tumor necrosis factor α (TNF-α), a pro-inflammatory cytokine, regulates inflammatory and immune responses by up-regulating gene expression in a manner that is dependent on the transcription factor ...nuclear factor κB (NF-κB). In the present study, we found that 4-hydroxypanduratin A and isopanduratin A, constituents of the rhizomes of Boesenbergia pandurata, inhibited the TNF-α-stimulated up-regulation of intercellular adhesion molecule-1 (ICAM-1) in human lung adenocarcinoma A549 cells. 4-Hydroxypanduratin A and isopanduratin A also reduced ICAM-1 mRNA expression and NF-κB-responsive luciferase activity in TNF-α-stimulated A549 cells. Moreover, 4-hydroxypanduratin A and isopanduratin A prevented the TNF-α-stimulated translocation of the NF-κB subunit p65 to the nucleus and the phosphorylation and proteasomal degradation of the inhibitor of the NF-κB α protein. The present results revealed that 4-hydroxypanduratin A and isopanduratin A inhibit TNF-α-stimulated gene expression and the NF-κB-dependent signaling pathway in A549 cells.
From the EtOAc extract of the wood of the stems of Taxotrophis ilicifolius (Moraceae), two new secondary metabolites, named taxotrophises A (1) and B (2), were isolated, together with five known ...compounds (3-7). Their chemical structures have been elucidated by extensive NMR spectroscopic analysis. All isolated compounds have been evaluated for α-glucosidase inhibitory activity. In the present work, compounds 1 and 4 showed the strongest α-glucosidase inhibitory activity with IC
50
values of 6.5 and 1.5 μM, respectively, and stronger than that of a positive control, acarbose (IC
50
; 214.5 μM).
Plants of the
family, specifically those belonging to the
species, are commonly under consideration as potential therapeutic agents for the management of gastrointestinal diseases. In this study, we ...carried out a phytochemical study on
Salisb. (or so-called "Nghe trang" in Vietnamese) grown in Vietnam, which yields three newly discovered 3,5-diacetoxy diarylheptanoids (1-3) and six known 3,5-dihydroxyl diarylheptanoids (4-9). The bioactivity assessment shows that all isolated compounds, except compounds 3, 7, and 8, could inhibit urease. Compounds 4 and 9 significantly inhibit urease, with an IC
value of 9.6 and 21.4 μM, respectively, more substantial than the positive control, hydroxyurea (IC
= 77.4 μM). The structure-activity relationship (SAR) of linear diarylheptanoids was also established, suggesting that the hydroxyl groups at any position of skeleton diarylheptanoids are essential for exerting anti-urease action. Through a comparative analysis of the binding sites of hydroxyurea and diarylheptanoid compounds
our constructed
model, the mechanism of action of diarylheptanoid compounds is predicted to bind to the dynamic region close to the dinickel active center, resulting in a loss of catalytic activity. Such insights certainly help design and/or find diarylheptanoid-based compounds for treating gastric ulcers through inhibiting urease.
From an ethyl acetate-soluble fraction of the leaves of Muntingia calabura, one new trimeric δ-tocopherol derivative named as tocomuntin A (1), together with three known δ-tocopherol derivatives ...(2-4) were isolated. Their structures were elucidated based on the interpretation of NMR and MS spectroscopic data. In this work, δ-tocopherol (3) was found to have α-glucosidase inhibitory activity for the first time (IC
50
, 47.3 μM).
Large-scale coastal erosion in the Mekong Delta has been dramatically increasing in severity in recent decades. There are several effective hard engineering solutions that have been implemented in ...this delta to efficiently prevent coastal erosion and stimulate sedimentation while supporting the local ecosystem conservation. These measures include Pile-Rock Breakwaters (PRBW), Hollow Triangle Breakwaters (HTB) and Semicircular Breakwaters (SBW). However, research on the sediment transport, morphological changes and toe erosion for these offshore breakwaters is very limited and is currently in the initial stages of understanding the specific conditions of sediment characteristics and foundations. The objective of this study was to reproduce the morphological changes and toe erosion of three breakwaters due to wave-structure interactions. This was investigated using 2D physical models with 3000 irregular waves during 8 experimental hours (equal to 15,000*Tp). To extract the bed morphological changes and toe erosion both specialized laser measurements (SW50M laser ruler) and analysis of high-speed video recording by images digitalization were applied. The experimental results show that the shape and structural design of offshore breakwaters can have a significant influence on the bed morphology on both the seaside and the leeside. We found that generally the toe of the construction on the seaside was eroded due to the occurrence of reflected waves, and that the flow is narrowed while passing through the construction, increasing the flow velocity and causing toe erosion. Additionally, the accretion of sediment at the leeside of the breakwaters was found to be mainly driven by the transport of sediment through the construction. Comparing the breakwater designs the experimental results showed that the HTB has the maximum accretion rate behind the structure, as well as the fastest accretion rate behind the breakwater. The SBW has high wave energy dissipation efficiency, although the toe erosion rate is faster than the other classes of breakwaters. The PRBW shows the fastest toe erosion rate in front of the structure and causes accretion at the leeside of the construction but at a lower rate than the HTB. The findings from this study will help practical designers to reinforce the foot of construction during real breakwater designing and inform stability calculations. We recommendation is to apply these three classes of breakwaters, especially the HTB and SBW, for stimulating sedimentation for mangrove restoration in the mangrove mud-coast delta.
•Morphology and toe erosion of three breakwaters were tested using laboratory physical models.•Pile-rock (PRBW), hollow triangle (HTB), and semi-circular breakwaters (SBW) are compared.•PRBW had the largest front erosion and the slowest accretion rate behind the structure.•HTB demonstrates the fastest accretion rate and the largest sedimentation area behind the breakwater.•SBW had high wave energy dissipation efficiency, but a faster toe erosion rate.
From an EtOAc-soluble fraction of the roots of
, one undescribed chromene derivative, paratrimerin Z (
), was isolated. Its structure was elucidated on the basis of NMR spectroscopic interpretation. ...The absolute configuration of
was determined by the specific rotation analysis of its acid-catalyzed hydrolysis product. Paratrimerin Z (
), at a concentration of 100
M, did not show cytotoxicity against Hep3B human liver cancer cell line.
From a CH2Cl2‐soluble fraction of the stem barks of Taxus wallichiana, one new abeo‐icetexane‐type diterpenoid, taxamairin I (1), was isolated. Its absolute configuration was elucidated based on ...spectroscopic interpretation and time‐dependent density functional theory (TD‐DFT) calculation of optical rotation. In addition, the plausible biosynthesis pathway for the formation of the new abeo‐icetexane‐type diterpenoid was proposed. Taxamairin I (1), at a concentration of 100 μM, did not show cytotoxicity against Hep3B human liver cancer cell lines.
Bioactivity-guided fractionation of the CHCl
3
-soluble extract of the roots of Paramignya trimera was carried out to obtain a new acridone alkaloid, paratrimerin I. Its structure was elucidated ...based on NMR spectroscopic data interpretation. Paratrimerin I showed noteworthy cytotoxicity against the HepG2 human hepatocellular and MCF-7 human breast carcinoma cell lines, with the submicromolar IC
50
values of 0.43 and 0.26 µM, respectively. The N-methyl, C-4 methoxy, and C-5 hydroxy groups in the acridone skeleton can be proposed as a structural feature for good cytotoxicity.
The study of small RNAs is a field that is expanding quickly. Other functional short RNA molecules other than microRNAs, and gene expression regulators, have been found in animals and plants. ...MicroRNAs play a significant role in host-microbe interactions, and parasite microRNAs may affect the host's innate immunity. Furthermore, short RNAs are intriguing non-invasive biomarker possibilities because they can be found in physiological fluids. These trends suggest that for many researchers, quick and simple techniques for expression profiling and subsequent downstream analysis of miRNA-seq data are crucial. We selected sRNAtoolbox to make integrated sRNA research easier. Each tool can be used separately or to explore and analyze sRNAbench results in further depth. A special focus was placed on the tools' usability. We review available miRNA research tools to have an overview of the evaluation of the tools. Mainly we evaluate the tool sRNAtoolbox.
Background
Tyrosinase is an oxidoreductase that is very important in medicine and cosmetics because the excessive production of melanin causes hyperpigmentation. The development of novel, effective ...tyrosinase inhibitors has long been pursued. In preliminary tests, we found that an extract of the wood of
Artocarpus heterophyllous
(AH) potently inhibited tyrosinase activity.
Results
Two new flavonoids, artocaepin E (
1
) and artocaepin F (
2
), were isolated from the wood of AH, together with norartocarpetin (
3
), artocarpanone (
4
), liquiritigenin (
5
), steppogenin (
6
), and dihydromorin (
7
). Their structures were elucidated using one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and mass spectrometry. The absolute configuration of
2
was determined from the circular dichroism (CD) spectrum. Artocarpanone (
4
) had the most potent tyrosinase inhibitory effect, with an IC
50
of 2.0 ± 0.1 μM, followed by artocaepin E (
1
) and steppogenin (
6
), with IC
50
values of 6.7 ± 0.8 and 7.5 ± 0.5 μM, respectively. A kinetic investigation indicated that
1
showed competitive inhibition, with an inhibition constant (
K
i
) of 6.23 μM.
Conclusions
These results demonstrate that extracts of the wood of AH and its phytochemical constituents are potential sources for skin-whitening agents.
Graphical abstract
Artocarmin E (1) and artocarmin F (2) were isolated from the wood of
Artocarpus heterophyllous
. Their structures were elucidated using nuclear magnetic resonance analysis and mass spectrometric methods
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