Natural Product Research最新文献

Antimycins are a class of depsipeptide compounds that exhibit diverse bioactivities. However, their potential clinical applications are hampered by high cell toxicities. Glycosylation usually has profound impacts on the physicochemical properties, bioactivities and toxicities of natural products. In this study, we overexpressed an artificial glycosyltransferase (GT) gene sbmGT1 in deepsea-derived Streptomyces albus ZH66, leading to the discovery of three new antimycin derivatives glucosylantimycins A, B and C (1-3). Their structures were determined by a combination of spectroscopic methods, including high resolution electrospray ionisation mass spectrometry (HRESIMS) and nuclear magnetic resonance (NMR) analysis. The glycosylation remarkably improved the water solubility but simultaneously reduced the cytotoxicities of antimycins towards human cervix epidermoid carcinoma (HeLa) and human hepatic carcinoma (HepG2) cell lines.

In this study, antiulcer activity of ethanolic extract and solvent fractions of the aerial part of Calendula tripterocarpa was investigated using ethanol-induced model of gastric ulceration in rats. The results showed that ethyl acetate, non-polar components and diethyl ether fractions have a remarkable antiulcerogenic activity; because they exhibited control-ulcer protection by 85.2%, 77.7% and 62.9%, respectively. The acute toxicity study showed that the extract is highly safe; the median lethal dose (LD₅₀) was more than 5000 mg/kg. Moreover, the obtained results were confirmed by the sub-chronic toxicity and showed no alteration in the liver and kidney functions. Our data suggests that C. tripterocarpa possesses significant antiulcer activity and it can be used as a source for an antiulcer drug. Around 100 compounds are elucidated from this plant using direct analysis in real-time of flight-mass spectrometry for the first time, of which four well-known compounds were not isolated or reported previously.

Two undescribed compounds, including one monoterpene (1) and one sesquiterpene (2), together with eleven known compounds were isolated from Platycladus orientalis. The structures of the isolated compounds were determined by comprehensive spectroscopic analysis; the absolute configurations of these compounds were determined by ECD calculation. Some of the compounds were tested for anti-inflammatory activity. The results showed that compounds 5-6, 9 and 12 exhibited NLRP3-inflammasome inhibitory activity.

Drone larvae (DL) has many biological activities thanks to the bioactive components it contains, but there are very few studies on its antimicrobial activity. The aim of this research was to determine the antifungal activity of DL (raw and lyophilised) water and ethanol extracts against fluconazole (FLU) sensitive and resistant yeast strains. The 87 fungal strains obtained from clinical samples were identified by phenotypic and molecular methods, and broth microdilution test was used for antifungal activity. All DL extracts had antifungal activity. The ethanolic extract of lyophilised DL showed higher antifungal activity. Total phenolic substance content and antioxidant activity of lyophilised DL ethanolic extract were found to be higher than other extracts. According to these results, the observed antifungal activity of DL extracts can be attributed not only to phenolic components, but also to synergistic effect of phenolic components with other bioactive components it contains.

Sophaline B (SPB), extracted from the seeds of Sophora alopecuroides L., is a natural bioactive compound that effectively exerts antiviral activities against the hepatitis B virus. This is the first study to demonstrate that SPB exerts anti-tumor effects on NSCLC by inducing pyroptosis and autophagy. SPB promotes NSCLC cell death by increasing the reactive oxygen species (ROS) production to induce pyroptosis via activating the NLRP3/Caspase-1/GSDMD signalling pathway. Meanwhile, SPB inhibits cancer cell proliferation by activating autophagy via blocking the PI3K/AKT/mTOR signalling pathway. Further investigation indicates that SPB inhibits NSCLC cell migration and invasion by increasing E-cadherin while decreasing N-cadherin, vimentin, and snail at the protein level. In addition, our results show that SPB inhibits cancer cell colony formation and human umbilical vein endothelial cell angiogenesis. Our study revealed the mechanisms of SPB triggering pyroptosis and autophagy in NSCLC, thus providing evidence and information on the SPB as an anti-cancer agent in NSCLC.

Dermatophagoides farinae is a species closely linked to human health. This study investigated the acaricidal efficacy of methanol extracts from 18 traditional Chinese medicinal plants against D. farinae. The extract from Ligusticum striatum DC. exhibited the highest acaricidal properties. Sequential extraction was applied to reveal the active component in the ethyl acetate extract, identified as senkyunolide A (SEA) by liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR) analyses. Transcriptomic analysis was performed following SEA exposure for 6, 12, and 24 h, revealing a total of 8212, 4000, and 10 940 differentially expressed genes (DEGs) in D. farinae, respectively. Gene Ontology (GO) enrichment analysis indicated that the DEGs in the three time periods were mainly enriched in cellular processes, binding and catalytic activity, and cell and cellular parts. Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis identified substantial changes in the oxidative phosphorylation pathway over the three time periods. These findings suggest that the acaricidal mechanism of SEA may disrupt energy metabolism, leading to metabolic disorders. SEA also exhibited an inhibitory effect on carboxylesterase among the detoxification enzyme genes, as well as an up-regulatory effect on calmodulin (CaM), which may lead to nerve cell death, ultimately resulting in the mortality of D. farinae.

Cancer kills about 10 million people every year. Medicinal plants remain a major source in the global search for anticancer drugs. In this study, 3,4,3'-tri-O-methylflavellagic acid (MFA) was isolated from the methanol root extract of Anogeissus leiocarpus. The structure was determined by 1D- and 2D-NMR data. The cytotoxic effects of MFA were evaluated against human breast (MCF-7), colorectal (Caco-2), and cervical (HeLa) cancer cell lines using the 3-[4,5-dimethylthiazole-2-yl] 3,5-diphenyltetrazolium bromide assay. A multi-protein target screening via molecular docking was conducted against ten cancer-related proteins, and ADMET properties were evaluated. MFA exhibited the most potent activity against Caco-2 (IC₅₀: 46.75 ± 13.00 µM). Molecular docking analysis showed that MFA had a strong binding affinity for the colchicine-binding site of αβ-tubulin and polo-like kinase-1 (binding energies: -8.5 and -8.4 kcal/mol, respectively). MFA also satisfied the Lipinski's Rule of Five. MFA could, therefore, potentially serve as a scaffold for developing new anticancer molecules.

As part of our plan to discover new bioactive ingredients from entomophagous fungi, a new macrolide compound, talarolide (1), and a new bioactive natural product, talarenal (2), with two known compounds, WF-3681 methy ester (3) and aspergillumarin A (4) were isolated from an insect derived strain Talaromyces rugulosus GIZ45-A37. The structures were determined based on extensive comprehensive spectroscopic (NMR and HR-ESI-MS) analyses and compared with literature values. The relative configuration of 1 was defined by DFT-NMR chemical shift calculations and subsequent DP4/DP4+ probability methods. Compounds 1 and 2 showed inhibitory effect on IL-6 production at 10 and 20 μM in LPS-stimulated beas-2b cells, indicating their potential anti-inflammatory activity.

Phytochemical investigation of the roots of Adenophora triphylla yielded a new phenylpropanoid, adenophoride (1) and a new polyacetylene, adenylene (7) along with four phenylpropanoids and a polyacetylene. The structures were determined by spectroscopic analysis including NMR, MS, UV and IR. Among the isolated compounds, phenylpropanoids including a new compound showed mild α-glucosidase inhibitory activities.

Labdane diterpenoid lactone andrographolide has gained attention in medicinal research due to its potential anticancer properties in terms of suppression of the growth, propagation, and relocation of various types of cancerous cells. The current review provides deep insight into the pharmacological analysis of the anticancer secondary metabolite andrographolide. We have attempted to keep an overview on the interaction of promising drugs like ligand molecule andrographolide with various biological targets. The observation indicates that andrographolide significantly down-regulates the growth of cancer cells through various mechanisms via diminishing inducible nitric oxide synthase (iNOS) expression, attenuating Akt and JNK signalling cascade, inhibiting NF-κB activation, ROS generation in the neoplastic cells etc. This bio-molecule is a potent therapeutic agent that can be applied in treating and preventing inflammatory vascular diseases. This study may be beneficial in the area of drug development research, leading to better management of cancer and many other inflammatory diseases.