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Biology subjects

Zhang, G.-J.

Publications and source records attributed to Zhang, G.-J..

2 recordsLinked to original sources

Comparative Analysis of Phytochemical Constituents of Ginkgo Biloba Flowers and Leaves, and Evaluation of Their Biological Activities

BackgroundsGinkgo biloba L. has attracted much attention for its unique chemical composition and pharmacological properties, and most of the research focused on Ginkgo biloba leaves (GBL). Our preliminary research found that Ginkgo biloba flowers (GBF) were superior to GBL in terms of anti-radiation activity, but the underlying cause of this discrepancy in activity remains elusive. ObjectivesThe aim of this study was to systematically compare the chemical and nutritional composition of Ginkgo biloba flowers and leaves, to further elucidate the material basis of the medicinal and nutritional value of Ginkgo biloba flowers, and to conduct further comparative studies on the anti-ferroptosis activity and anti-radiation activity of the two. MethodsIn this study, the chemical constituents of GBF and GBL were identified by UPLC-Q-orbitrap HRMS, and the contents of amino acids, fatty acids, inorganic elements, purines, and ceramides of both were determined. Meanwhile, the anti-iron death activity and anti-radiation activity of GBF and GBL were comparatively studied by cellular experiments. ResultsThe results showed that the content of chemical components such as flavonoids and other nutrients such as amino acids, fatty acids, and ceramides were richer in GBF than in GBL, and GBF was indeed superior to GBL in terms of anti-radiation and anti-ferroptosis activity. ConclusionThrough in-depth analyses of the chemical and nutritional compositions of Ginkgo biloba flowers and leaves, the present study reveals the possible material basis for the stronger activity of GBF and provides theoretical support for its application in nutraceuticals and pharmaceuticals, especially in the development of functional nutraceuticals and anti-radiation drugs with higher health benefits.

biochemistry↗

Identification of bis-benzylisoquinoline alkaloids as SARS-CoV-2 entry inhibitors from a library of natural products in vitro

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a major public health issue. To screen for antiviral drugs for COVID-19 treatment, we constructed a SARS-CoV-2 spike (S) pseudovirus system using an HIV-1-based lentiviral vector with a luciferase reporter gene to screen 188 small potential antiviral compounds. Using this system, we identified nine compounds, specifically, bis-benzylisoquinoline alkaloids, that potently inhibited SARS-CoV-2 pseudovirus entry, with EC50 values of 0.1-10 M. Mechanistic studies showed that these compounds, reported as calcium channel blockers (CCBs), inhibited Ca2+-mediated membrane fusion and consequently suppressed coronavirus entry. These candidate drugs showed broad-spectrum efficacy against the entry of several coronavirus pseudotypes (SARS-CoV, MERS-CoV, SARS-CoV-2 [S-D614, S-G614, N501Y.V1 and N501Y.V2]) in different cell lines (293T, Calu-3, and A549). Antiviral tests using native SARS-CoV-2 in Vero E6 cells confirmed that four of the drugs (SC9/cepharanthine, SC161/hernandezine, SC171, and SC185/neferine) reduced cytopathic effect and supernatant viral RNA load. Among them, cepharanthine showed the strongest anti-SARS-CoV-2 activity. Collectively, this study offers new lead compounds for coronavirus antiviral drug discovery.

microbiology↗