The ongoing COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a globally leading public health concern over the past two years. Despite the development and administration of multiple vaccines, the mutation of newer strains and challenges to universal immunity has shifted the focus to the lack of efficacious drugs for therapeutic intervention for the disease. As with SARS-CoV, MERS-CoV, and other non-respiratory viruses, flavonoids present themselves as a promising therapeutic intervention given their success in silico, in vitro, in vivo, and more recently, in clinical studies. This review focuses on data from in vitro studies analyzing the effects of flavonoids on various key SARS-CoV-2 targets and presents an analysis of the structure-activity relationships for the same. From 27 primary papers, over 69 flavonoids were investigated for their activities against various SARS-CoV-2 targets, ranging from the promising 3C-like protease (3CLpro) to the less explored nucleocapsid (N) protein; the most promising were quercetin and myricetin derivatives, baicalein, baicalin, EGCG, and tannic acid. We further review promising in silico studies featuring activities of flavonoids against SARS-CoV-2 and list ongoing clinical studies involving the therapeutic potential of flavonoid-rich extracts in combination with synthetic drugs or other polyphenols and suggest prospects for the future of flavonoids against SARS-CoV-2.

Strain B66T was isolated from a marine water sample collected at Al Ruwais, located on the northern tip of Qatar. Cells were Gram-stain-negative, strictly aerobic and short- rod-shaped with a polar flagellum. The isolate was able to grow at 15–45 °C (optimum, 30 °C), at pH 5–11 (optimum, pH 6.5–8) and with 0–6 % NaCl. 16S rRNA gene sequence analysis revealed that strain B66T was affiliated with the family Alteromonadaceae , sharing the highest sequence similarities to the genera Alteromonas (93.7–95.4 %), Aestuariibacter (94.0–95.1 %), Agaribacter (93.3–93.7 %), Glaciecola (92.0–93.7 %), Marisendiminitalea (93.2–93.3 %) and Planctobacterium (92.9 %). In the phylogenetic trees, strain B66T demonstrated the novel organism formed a distinct lineage closely associated with Aestuariibacter and Planctobacterium . Major fatty acids were C16 : 0, summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c/iso-C15 : 0 2-OH and iso-C15 : 0 3-OH. The major respiratory quinone was ubiquinone-8 and the major polar lipids are phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content derived from the genome was 43.2 mol%. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic data, strain B66T is considered to represent a novel species and genus for which the name Ningiella ruwaisensis gen. nov., sp. nov., is proposed. The type strain is B66T (=QCC B003/17T=LMG 30288 T=CCUG 70703T).

No abstract

Since the discovery of the severe acute respiratory syndrome coronarvirus 2 (SARS‐CoV‐2) numerous research was undertaken to delineate the various effects of the virus which manifests in many ways all over the body. The association between the SARS‐CoV‐2 invasion mechanism and the RAAS receptors, created many debates about the possible consequences of using RAAS modulating drugs including the ACE inhibitors (ACEi) and the Angiotensin II Receptor Blockers (ARBs) during the pandemic. Many clinical studies were conducted to assess the outcomes of COVID‐19 in patients who use ACEi/ARBs following the arguments claiming to discontinue these drugs as a precautionary measure. While several studies mainly analyzed the outcomes of the disease, this review aimed at comparing specific blood markers in both groups of COVID‐19 patients in order to gain a better insight into the interaction of ACEi/ARBs with the different body functions during the infection. Several databases were searched using a combination of keywords followed by screening and data extraction. Only 28 studies met our inclusion criteria, the majority of which showed no significant difference between the inflammation markers of COVID‐19 patients who used or did not use ACEi/ARBs. Interestingly, six studies reported lower inflammatory markers in COVID‐19 patients who used ACEi/ARBs and ten studies reported better outcomes among the same group. We therefore conclude that the use of ACEi/ARBs may not lead to worse prognosis of COVID‐19 and may even play a protective role against the hyperinflammatory response associated with COVID‐19. This article is protected by copyright. All rights reserved

No abstract