Sep 28 |
Quercetin for COVID-19: real-time meta analysis of 11 studies | |
| Statistically significant lower risk is seen for ICU admission, hospitalization, recovery, cases, and viral clearance. 10 studies from 8 independent teams in 7 countries show statistically significant improvements. • Meta analysis using.. | ||
Sep 26 |
et al., Food Science & Nutrition, doi:10.1002/fsn3.3715 | The effect of quercetin supplementation on clinical outcomes in |
| Systematic review and meta analysis of 5 studies, showing significantly lower mortality, ICU admission, and hospitalization with quercetin treatment. | ||
Sep 19 |
et al., Makara Journal of Science, doi:10.7454/mss.v27i3.1609 | In-silico Approach for Predicting the Inhibitory Effect of Home Remedies on Severe Acute Respiratory Syndrome Coronavirus-2 |
| In Silico analysis showing that curcumin and quercetin may be beneficial for COVID-19 by binding to the main protease (Mpro), spike protein, and ACE2 receptor. Both compounds had suitable ADME properties and minimal predicted toxicity. | ||
Sep 5 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2309870120 | Reply to Yan et al.: Quercetin possesses a fluorescence quenching effect but is a weak inhibitor against SARS-CoV-2 main protease |
| In Vitro study [Yan] and associated response from the original authors [Xu], collectively showing that quercetin and echinatin had weak SARS-CoV-2 protease inhibition in SDS-PAGE assays [Xu], despite false positive FRET results from MCA-A.. | ||
Sep 5 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2309289120 | Reframing quercetin as a promiscuous inhibitor against SARS-CoV-2 main protease |
| In Vitro study [Yan] and associated response from the original authors [Xu], collectively showing that quercetin and echinatin had weak SARS-CoV-2 protease inhibition in SDS-PAGE assays [Xu], despite false positive FRET results from MCA-A.. | ||
Aug 3 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2023.1241016 | Association of dietary intake of polyphenols, lignans, and phytosterols with immune-stimulating microbiota and COVID-19 risk in a group of Polish men and women |
| Dietary analysis of 95 adults in Poland, showing lower risk of COVID-19 with higher intake of polyphenols, lignans, and phytosterols. Results were statistically significant for total phytosterols, secoisolariciresinol, β-sitosterol, matai.. | ||
Jul 13 |
et al., Journal of Traditional and Complementary Medicine, doi:10.1016/j.jtcme.2023.07.004 | In silico anti-viral assessment of phytoconstituents in a traditional (Siddha Medicine) polyherbal formulation – Targeting Mpro and pan-coronavirus post-fusion Spike protein |
| In Silico analysis of phytoconstituents of Kabasura Kudineer against SARS-CoV-2 spike protein and Mpro, showing that quercetin (Mpro) and gallic acid (spike) had the highest binding affinity and stability. | ||
Jun 30 |
et al., International Journal of Biological Macromolecules, doi:10.1016/j.ijbiomac.2023.125553 | Computational analysis of the phytocompounds of Mimusops elengi against spike protein of SARS CoV2 – An Insilico model |
| In Silico study finding that quercetin and hederagenin showed very high binding affinities for COVID-19 associated receptors MMP9 and IL6. | ||
Jun 22 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2023.1137407 | NASAFYTOL® supplementation in adults hospitalized with COVID-19 infection: results from an exploratory open-label randomized controlled trial |
| 91% lower combined mortality/ICU admission (p=0.02), 89% lower ventilation (p=0.05), 89% lower ICU admission (p=0.05), and 73% higher hospital discharge (p=0.07). RCT 49 hospitalized COVID-19 patients, 25 treated with curcumin and quercetin, shower lower mortality/ICU admission and improved recovery with treatment. All patients received vitamin D. 336mg curcumin, 520mg quercetin, and 18μg vitamin D.. | ||
Jun 3 |
et al., Biotechnology & Biotechnological Equipment, doi:10.1080/13102818.2023.2222196 | Inhibitory potential of phytochemicals on five SARS-CoV-2 proteins: in silico evaluation of endemic plants of Bosnia and Herzegovina |
| In Silico study of phytochemicals from 28 plants identifying hesperidin and quercetin as having the highest binding affinity for SARS-CoV-2 RdRp. The highest affinity for Mpro was observed for genistein and hesperidin, with both compounds.. | ||
Jun 2 |
et al., 11th International Seminar on New Paradigm and Innovation on Natural Sciences and its Application, doi:10.1063/5.0140285 | Utilization of quercetin flavonoid compounds in onion (Allium cepa L.) as an inhibitor of SARS-CoV-2 spike protein against ACE2 receptors |
| In Silico study showing high affinity binding between the SARS-CoV-2 spike protein and quercetin, and analysis of the quercetin content of onion. | ||
May 18 |
et al., Frontiers in Pharmacology, doi:10.3389/fphar.2023.1188086 | In silico evidence implicating novel mechanisms of Prunella vulgaris L. as a potential botanical drug against COVID-19-associated acute kidney injury |
| In Silico study identifying quercetin, luteolin and kaempferol as potentially protective for COVID-19 acute kidney injury. | ||
May 15 |
et al., Journal of Modern Biology and Drug Discovery, doi:10.53964/jmbdd.2023004 | Use of Quercetin for Therapeutic Purposes in COVID-19 Infections: The Opinion of the Geriatrician Doctor |
| Review of the antiviral properties and potential benefits of quercetin for COVID-19. | ||
Apr 24 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2301775120 | Bioactive compounds from Huashi Baidu decoction possess both antiviral and anti-inflammatory effects against COVID-19 |
| In Vitro study of compounds from Huashi Baidu (Q-14), showing dose-dependent inhibition of SARS-CoV-2 with quercetin. Authors also perform a mouse study showing that Q-14 decreases SARS-CoV-2 viral load and reduces pulmonary inflammation... | ||
Mar 31 |
et al., Society of Toxicology Conference, 2023 | Computational Analysis of Lianhua Qingwen as an Adjuvant Treatment in Patients with COVID-19 |
| In Silico analysis of components of Lianhua Qingwen, identifying quercetin, luteolin, wogonin, and phillyrin as potentially beneficial for COVID-19. Authors note that quercetin bound to Mpro at the same inhibitory pocket as nirmatrelvir (.. | ||
Mar 22 |
et al., Informatics in Medicine Unlocked, doi:10.1016/j.imu.2023.101230 | Computational studies of potential antiviral compounds from some selected Nigerian medicinal plants against SARS-CoV-2 proteins |
| In Silico study identifying quercetin and naringenin as potent multitarget-directed ligands for 3CLpro, PLpro, and ACE2 with favorable ADME properties. | ||
Feb 13 |
et al., Reviews in Medical Virology, doi:10.1002/rmv.2427 | Quercetin for the treatment of COVID-19 patients: A systematic review and meta-analysis |
| Systematic review and meta analysis of 6 quercetin RCTs, showing significantly lower hospitalization and ICU admission. Differences for mortality and recovery were not statistically significant. | ||
Jan 26 |
et al., Aging Cell, doi:10.1111/acel.13771 | Treatment with the senolytics dasatinib/quercetin reduces SARS-CoV-2 related mortality in mice |
| K18-hACE2 mouse study showing reduced COVID-19 severity with quercetin and dasatinib, for both prophylaxis and early treatment. | ||
Jan 25 |
et al., Emergent: Journal of Educational Discoveries and Lifelong Learning | Applications of quercetin for the prevention of COVID-19 in healthcare workers |
| 96% lower mortality (p<0.0001) and 98% fewer symptomatic cases (p<0.0001). Prospective study of healthcare workers in Uzbekistan showing lower mortality and cases with quercetin prophylaxis. Very minimal details are provided, there is no baseline information, and control mortality is very high. | ||
Jan 18 |
et al., bioRxiv, doi:10.1101/2023.01.17.524329 | Senolytic therapy alleviates physiological human brain aging and COVID-19 neuropathology |
| In Vitro and animal study showing that senolytics including dasatinib + quercetin improve survival and mitigate neuropathological sequelae of SARS-CoV-2. Authors show that SARS-CoV-2 can initiate cellular senescence in the brains of COVID.. | ||
Jan 18 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2022.1023997 | The possible therapeutic role of curcumin and quercetin in the early-stage of COVID-19—Results from a pragmatic randomized clinical trial |
| 29% improved recovery (p=0.11) and 91% improved viral clearance (p=0.05). Small RCT with 50 outpatients, 25 treated with curcumin, quercetin, and vitamin D, showing improved recovery and viral clearance with treatment. 168mg curcumin, 260mg, 360IU vitamin D3 daily for 14 days. | ||
Jan 17 |
et al., Molecules, doi:10.3390/molecules28030938 | Quercetin: A Functional Food-Flavonoid Incredibly Attenuates Emerging and Re-Emerging Viral Infections through Immunomodulatory Actions |
| Review of the antiviral properties of quercetin and derivatives, and potential mechanisms of action. | ||
Jan 16 |
et al., The Gazette of Medical Sciences, doi:10.46766/thegms.pubheal.22120905 | Intravenous high dose vitamin C and ozonated saline effective treatment for Covid -19: The Evolution of Local Standard of Care |
| Retrospective 479 high risk outpatients in the USA treated with a protocol including intravenous vitamin C, vitamin D, zinc, quercetin, bromelain, lactoferrin, HCQ, ivermectin, ozonated saline, azithromycin, ceftriaxone, methylprednisolon.. | ||
Jan 13 |
et al., Frontiers in Pharmacology, doi:10.3389/fphar.2022.1096853 | Quercetin as a possible complementary agent for early-stage COVID-19: Concluding results of a randomized clinical trial |
| 37% improved recovery (p=0.007) and 58% improved viral clearance (p<0.0001). RCT 100 outpatients in Pakistan, 50 treated with quercetin phytosome, showing faster viral clearance and improved recovery with treatment. Patients in the treatment group were significantly younger (41 vs. 54). | ||
Jan 12 |
et al., Bioinformatics and Biology Insights, doi:10.1177/11779322221149622 | The Potential of Ameliorating COVID-19 and Sequelae From Andrographis paniculata via Bioinformatics |
| In Silico study of components of andrographis paniculata, identifying multiple components including quercetin as promising inhibitors of SARS-CoV-2. Authors note the potential synergistic effect with multiple compounds. | ||
Dec 12 2022 |
et al., Molecular Therapy, doi:10.1016/j.ymthe.2022.12.002 | Treatment with Quercetin inhibits SARS-CoV-2 N protein-induced acute kidney injury by blocking Smad3-dependent G1 cell cycle arrest |
| Mouse study showing quercetin can significantly inhibit SARS-CoV-2 induced acute kidney injury via blocking of SARS-CoV-2 N-Smad3-mediated cell death. | ||
Nov 29 2022 |
et al., Biomedicines, doi:10.3390/biomedicines10123074 | Interaction of Epigallocatechin Gallate and Quercetin with Spike Glycoprotein (S-Glycoprotein) of SARS-CoV-2: In Silico Study |
| In Silico study suggesting efficacy of epigallocatechin gallate and quercetin for SARS-CoV-2. | ||
Oct 18 2022 |
et al., Journal of Clinical Medicine, doi:10.3390/jcm11206138 | Early Outpatient Treatment of COVID-19: A Retrospective Analysis of 392 Cases in Italy |
| Retrospective 392 outpatients in Italy showing 0.2% mortality with early treatment, compared with >3% in Italy at the time. Treatment varied for individual patients and included HCQ, vitamin D, vitamin C, vitamin A, zinc, quercetin, bromh.. | ||
Aug 25 2022 |
et al., Pharmaceuticals, doi:10.3390/ph15091049 | Quercetin in the Prevention and Treatment of Coronavirus Infections: A Focus on SARS-CoV-2 |
| Review of the potential benefits of quercetin for COVID-19, including inhibitory effects on several stages of the viral life cycle, antioxidant, anti-inflammatory, and immunomodulatory effects, and synergistic effects with other treatments. | ||
Aug 10 2022 |
et al., Journal of King Saud University - Science, doi:10.1016/j.jksus.2022.102277 | Docking and molecular dynamics studies of human ezrin protein with a modelled SARS-CoV-2 endodomain and their interaction with potential invasion inhibitors |
| In Silico study of SARS-CoV-1&2 endodomains and ezrin docking, identifying ivermectin, quercetin, calcifediol, calcitriol, selamectin, and minocycline as potential therapeutic drugs with strong ezrin binding which may restrict viral endod.. | ||
Jun 16 2022 |
et al., International Journal of Translational Medicine, doi:10.3390/ijtm2020022 | Evaluation of the Clinical Effects of an Antiviral, Immunostimulant and Antioxidant Phytotherapy in Patients Suffering from COVID-19 Infection: An Observational Pilot Study |
| Retrospective case series of 240 patients in Italy in 2020, up to 96 years old, showing no mortality and 1.6% hospitalization with early treatment including vitamin C, quercetin, and green tea and red wine polyphenols. The formulation was.. | ||
May 20 2022 |
et al., medRxiv, doi:10.1101/2022.05.16.22275074 | Jinhua Qinggan Granules for Nonhospitalized COVID-19 Patients: a Double-Blind, Placebo-Controlled, Randomized Controlled Trial |
| 81% greater improvement (p<0.0001) and 8% worse viral clearance (p=0.48). RCT 300 outpatients in China, showing improved recovery with Jinhua Qinggan treatment, but no significant difference in viral clearance or radiographic findings. Jinhua Qinggan includes quercetin, rutin, luteolin, wogonin, myricetin, urso.. | ||
May 15 2022 |
et al., Life Research, doi:10.53388/life2022-0205-302 | The pharmacological mechanism of quercetin as adjuvant therapy of COVID-19 |
| Review of in silico and clinical evidence supporting the use of quercetin for COVID-19. | ||
May 1 2022 |
et al., Frontiers in Pharmacology, doi:10.3389/fphar.2022.898062 | Oral Co-Supplementation of Curcumin, Quercetin, and Vitamin D3 as an Adjuvant Therapy for Mild to Moderate Symptoms of COVID-19—Results From a Pilot Open-Label, Randomized Controlled Trial |
| 33% improved recovery (p=0.15) and 50% improved viral clearance (p=0.009). RCT 50 COVID+ outpatients in Pakistan, 25 treated with curcumin, quercetin, and vitamin D, showing significantly faster viral clearance, significantly improved CRP, and faster resolution of acute symptoms (p=0.154). 168mg curcumin, 260mg .. | ||
Apr 29 2022 |
et al., Antioxidants, doi:10.3390/antiox11050876 | The Therapeutic and Prophylactic Potential of Quercetin against COVID-19: An Outlook on the Clinical Studies, Inventive Compositions, and Patent Literature |
| Review of the evidence supporting the use of quercetin for COVID-19 from clinical studies and patents. | ||
Jan 21 2022 |
et al., European Journal of Microbiology and Immunology, doi:10.1556/1886.2021.00022 | Inhibitory effects of specific combination of natural compounds against SARS-CoV-2 and its Alpha, Beta, Gamma, Delta, Kappa, and Mu variants |
| In Vitro study testing combinations of plant extracts and micronutrients with several variants of SARS-CoV-2. A combination of vitamin C, N-acetylcysteine, curcumin, quercetin, resveratrol, theaflavin, naringenin, baicalin, and broccoli e.. | ||
Jan 4 2022 |
et al., Life, doi:10.3390/life12010066 | Promising Effects of 3-Month Period of Quercetin Phytosome® Supplementation in the Prevention of Symptomatic COVID-19 Disease in Healthcare Workers: A Pilot Study |
| 93% fewer symptomatic cases (p=0.04). RCT 120 healthcare workers, 60 treated with quercetin phytosome, showing lower risk of cases with treatment. Quercetin phytosome 250mg twice a day. | ||
Dec 28 2021 |
et al., Research Square, doi:10.21203/rs.3.rs-1149846/v1 | Quercetin and Luteolin Are Single-digit Micromolar Inhibitors of the SARS-CoV-2 RNA-dependent RNA Polymerase |
| In Vitro and In Silico study showing quercetin and luteolin inhibiting SARS-CoV-2 RNA-dependent RNA polymerase (RdRp). | ||
Dec 14 2021 |
et al., Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, doi:10.1016/j.bbadis.2021.166322 | The spike protein of SARS-CoV-2 virus induces heme oxygenase-1: Pathophysiologic implications |
| In Vitro study transfecting SARS-CoV-2 viral spike protein in kidney cell lines, showing syncytia formation and upregulation of the cytoprotective gene HO-1, and that quercetin, which induces HO-1, can reduce syncytia formation. Authors c.. | ||
Dec 8 2021 |
et al., Medical Science Monitor, doi:10.12659/MSM.935379 | Retrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis of Early COVID-19 and Treated at Home Within 3 Days or After 3 Days of Symptom Onset with Prescribed and Non-Prescribed Treatments Between November 2020 and August 2021 |
| Retrospective 158 COVID-19 patients in Italy treated with hesperidin, quercetin, indomethacin, aspirin, omeprazole, azithromycin, LMWH, and betamethasone (treatment specific for each patient), showing significantly lower hospitalization a.. | ||
Dec 2 2021 |
et al., European Journal of Pharmacology, doi:10.1016/j.ejphar.2021.1746158 | The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial |
| 86% lower mortality (p=0.24) and 32% faster recovery (p=0.04). Small RCT with 60 severe hospitalized patients in Iran, 30 treated with quercetin, showing shorter time until discharge. All patients received remdesivir or favipiravir, and vitamin C, vitamin D, famotidine, zinc, dexamethasone, and magne.. | ||
Nov 14 2021 |
et al., Food Chemistry, doi:10.1016/j.foodchem.2021.131594 | Inhibition of the SARS-CoV-2 3CLpro main protease by plant polyphenols |
| In Silico and In Vitro study of plant polyphenols identifying quercetin, curcumin, ellagic acid, epigallocatechin gallate, and resveratrol as SARS-CoV-2 3CLpro inhibitors with IC50 between 11.8µM and 23.4µM. Real-time binding was analyzed.. | ||
Sep 29 2021 |
et al., Journal of Molecular Graphics and Modelling, doi:10.1016/j.jmgm.2021.108038 | In silico identification of SARS-CoV-2 cell entry inhibitors from selected natural antivirals |
| In Silico study identifying quercetin derivatives as SARS-CoV-2 spike protein, ACE2, and neuropilin inhibitors. | ||
Sep 1 2021 |
et al., Zaporozhye Med. J., doi:10.14739/2310-1210.2021.5.231714 | Quercetin effectiveness in patients with COVID-19 associated pneumonia |
| 29% improved recovery (p=0.5). RCT 200 patients in Ukraine, 99 treated with IV quercetin/polyvinylirolidone followed by oral quercetin/pectin, showing improved recovery with treatment. | ||
Jul 6 2021 |
et al., Journal of Evidence-Based Integrative Medicine, doi:10.1177/2515690X211026193 | 20-Week Study of Clinical Outcomes of Over-the-Counter COVID-19 Prophylaxis and Treatment |
| 94% fewer cases (p=0.003). Retrospective 113 outpatients, 53 (patient choice) treated with zinc, quercetin, vitamin C/D/E, l-lysine, and quina, showing lower cases with treatment. Results are subject to selection bias and limited information on the groups is provid.. | ||
Jun 15 2021 |
et al., Pathogens, doi:10.3390/pathogens10060758 | Bioactive Polyphenolic Compounds Showing Strong Antiviral Activities against Severe Acute Respiratory Syndrome Coronavirus 2 |
| Vero E6 In Vitro study showing curcumin, hesperidin, and quercetin significantly inhibited SARS-CoV-2 replication, and In Silico analysis with promising Mpro and spike docking results. | ||
Jun 8 2021 |
et al., International Journal of General Medicine, doi:10.2147/IJGM.S318720 | Possible Therapeutic Effects of Adjuvant Quercetin Supplementation Against Early-Stage COVID-19 Infection: A Prospective, Randomized, Controlled, and Open-Label Study |
| 86% lower mortality (p=0.25), 94% lower ICU admission (p=0.006), and 68% lower hospitalization (p=0.003). RCT 152 outpatients in Pakistan, 76 treated with quercetin phytosome, showing lower mortality, ICU admission, and hospitalization with treatment. | ||
Apr 8 2021 |
et al., Journal of Advances in Medical and Pharmaceutical Sciences, doi:10.9734/jamps/2021/v23i330222 | Oral Quercetin in Adult Patients as a Potential Nutraceutical against Coronavirus Disease 2019 (COVID-19) |
| Prospective study of 52 patients treated with quercetin. There was no control group. | ||
Jan 19 2021 |
et al., Turk. J. Biol., 45:518-529 (date from preprint) | Treatment of COVID-19 patients with quercetin: a prospective, single center, randomized, controlled trial |
| 94% lower ICU admission (p=0.39) and 78% higher hospital discharge (p=0.1). RCT 447 moderate-to-severe hospitalized patients in Turkey, 52 treated with quercetin, bromelain, and vitamin C, showing no statistically significant difference in clinical outcomes. NCT04377789. | ||
Nov 16 2020 |
et al., SSRN, doi:10.2139/ssrn.3682517 | Synergistic Effect of Quercetin and Vitamin C Against COVID-19: Is a Possible Guard for Front Liners |
| 92% fewer cases (p=0.03). Small prophylaxis RCT with 113 patients showing fewer cases with quercetin + vitamin C + bromelain prophylaxis. NCT04377789. Note that this paper disappeared from SSRN without explanation. | ||
Oct 9 2020 |
et al., Phytotherapy Research, doi:10.1002/ptr.6887 | A role for quercetin in coronavirus disease 2019 (COVID-19) |
| Review noting that quercetin has a theoretical, but significant, capability to interfere with SARS-CoV-2 replication, with results showing this to be the fifth best compound out of 18 candidates. | ||
Jun 19 2020 |
et al., Frontiers in Immunology, doi:10.3389/fimmu.2020.01451 | Quercetin and Vitamin C: An Experimental, Synergistic Therapy for the Prevention and Treatment of SARS-CoV-2 Related Disease (COVID-19) |
| Review of the evidence for the use of vitamin C and quercetin both for prophylaxis in high-risk populations and for the treatment of COVID-19 patients. | ||
Apr 24 2020 |
et al., ChemRxiv, doi:10.26434/chemrxiv.12181404.v1 | In-Silico Identification of Potent Inhibitors of COVID-19 Main Protease (Mpro) and Angiotensin Converting Enzyme 2 (ACE2) from Natural Products: Quercetin, Hispidulin, and Cirsimaritin Exhibited Better Potential Inhibition than Hydroxy-Chloroquine Against COVID-19 Main Protease Active Site and ACE2 |
| In Silico study of natural compounds identifying quercetin, curcumin, hispidulin, cirsimaritin, sulfasalazine, and artemisin as potential compounds that inhibit SARS-CoV-2. | ||
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