Publications by authors named "Qing-Huang Wang"

is a destructive oomycete pathogen that causes devastating disease in black pepper, resulting in a significant decline in yield and economic losses. (black pepper) is documented as susceptible to , whereas its close relative is known to be resistant. However, the molecular mechanism underlying the resistance of remains obscure.

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Chitosan as a natural polysaccharide derived from chitin of arthropods like shrimp and crab, attracts much interest due to its inherent properties, especially for application in biomedical materials. Presently, biodegradable and biocompatible chitosan nanoparticles are attractive for drug delivery. However, some physicochemical characteristics of chitosan nanoparticles still need to be further improved in practice.

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Five new 2-(2-phenylethyl)chromone derivatives, qinanones A-E (1-5), together with eight known 2-(2-phenylethyl)chromone derivatives (6-13), were isolated from the Et2O extract of high-quality Chinese agarwood "Qi-Nan" originating from Aquilaria sinensis. The structures of the new 2-(2-phenylethyl)chromones were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses. In the bioassay for acetylcholinesterase inhibitors, compounds 1-6, 10, and 12 exhibited weak inhibitory activities (inhibition percentage ranged from 10 % to 24 % at the concentration of 50 µg/mL).

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A new denitroaristolochic acid, demethylaristofolin C (1), together with six known alkaloids, crebanine N-oxide (2), (-)-sukhodianine-β-N-oxide (3), palmatine (4), corydalmine (5), dehydrocorydalmine (6), and corynoxidine (7), was isolated from the tubers of Stephania succifera. The structure of demethylaristofolin C was elucidated by spectroscopic techniques (UV, IR, 1D, and 2D NMR) and HR-ESI-MS analyses. These compounds exhibited antibacterial activities against Staphylococcus aureus and methicillin-resistant S.

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A novel degraded sesquiterpene, named aquilarin B (1), together with two known compounds (2 and 3), was isolated from the EtOH extract of the fresh stem of Aquilaria sinensis (Lour.) Gilg. Their structures were elucidated by spectroscopic methods including 1D and 2D NMR (HMQC, (1)H-(1)H COSY, HMBC, and ROESY).

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Chemical investigation of the EtOH extract of the fresh stem of Aquilaria sinensis collected in Hainan Province of China resulted in the isolation of a new benzenoid, named aquilarin A (1), together with two known compounds balanophonin (2) and (+)-lariciresinol (3). Their structures were elucidated by a study of their physical and spectral data. Compounds 2 and 3 exhibited cytotoxicity against SGC-7901 and SMMC-7721 cell lines.

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