Anti‐neuraminidase activity of chemical constituents of Balanophora involucrata

Abstract

Balanophora involucrata J. D. Hooker has been known to possess potential anti‐inflammatory and antibacterial activities; however, its antiviral activity has not been evaluated so far. In order to find new neuraminidase inhibitors (NAIs), the neuraminidase (NA) inhibition activity of different B. involucrata extracts was evaluated. In this study, an in vitro NA inhibition assay was performed to identify which extract of B. involucrata exhibits (maximal) inhibitory activity against NA. Ultra high performance liquid chromatography/quadrupole time‐of‐flight–tandem mass spectroscopy (MS/MS) and molecular docking techniques were used to identify the specific compounds responsible for the anti‐influenza activity of the extract, and to explore the potential natural NAIs. The ethyl acetate extract of B. involucrata exhibited significant inhibitory activity against NA with 50% inhibitory concentration (IC50) value of 159.5 μg/mL. Twenty compounds were identified according to the MS/MS spectra; among them two compounds (quercitrin and phloridzin) showed obvious inhibitory activity against NA, with IC50 of 311.76 and 347.32 μmol/L, respectively. This study suggested that B. involucrata can be a potential natural source of NAIs and may be useful in the fight against ferocious influenza viruses.

Comparative pharmacognosy and secondary metabolite analysis of Balanophorae herbs from different sources

“…As shown in Table S1 , 41 compounds were identified or characterized in the mixed extracts of 209 samples based on standards and relevant literature [ 3 , 23 – 27 ]. The 41 compounds included 17 phenolic acids and their derivatives, 19 flavonoids and their derivatives, and 5 others.…”

The antiviral activity of Thuja orientalis folium against Influenza A virus

“…HPLC analysis detected quercitrin, myricetin, afzelin, quercetin, and amentoflavone in TOF. Several researches showed that quercitrin blocks IAV infection by controlling TLR signaling and inhibiting NA and NS1 proteins in the docking studies ( Ahmad et al., 2015 ; Ling et al., 2020 ; Sun et al., 2020 ; Tang et al., 2023 ). Our previous study showed that quercetin inhibits IAV attachment and entry at an early infection ( Cho and Ma, 2022 ).…”

Phytochemicals with Added Value from Morella and Myrica Species

“…Antiviral Activity [37] Neuraminidase inhibition: IC 50 = 311.76 µM (Oseltamivir acid IC 50 = 280 µM). Myeloperoxidase inhibition [38] IC 50 = 2.0 ± 0.2 µM Prevention of metal toxicity effects [39] Almost 100% HepG2 cell line viability when treated with 1 µM + 15 µM MeHg (50% viability when only treated with 15 µM MeHg).…”

“…Further investigations are necessary to explain the cytoprotective mechanism of the compound. Quercitrin (9) also presents a moderate antiviral activity by inhibition of neuraminidase (NA) [37], a viral enzyme common in human influenza viruses, which is essential for the virus release from infected cells to the neighboring cells of the respiratory tract [69]. It has also been reported that quercitrin (9) inhibits the activity of myeloperoxidase, with an IC 50 of 2.0 µM [38], a result that hints at its possible role in reducing endothelial dysfunction and consequently that the protective effect of 9 should be evaluated in an atherosclerosis model.…”