In vitro efficacy of Artemisia extracts against SARS-CoV-2

Abstract

Background Traditional medicines based on herbal extracts have been proposed as affordable treatments for patients suffering from coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Teas and drinks containing extracts of Artemisia annua and Artemisia afra have been widely used in Africa in efforts to prevent SARS-CoV-2 infection and fight COVID-19. Methods The plant extracts and Covid-Organics drink produced in Madagascar were tested for plaque reduction using both feline coronavirus and SARS-CoV-2 in vitro. Their cytotoxicities were also investigated. Results Several extracts as well as Covid-Organics inhibited SARS-CoV-2 and FCoV infection at concentrations that did not affect cell viability. Conclusions Some plant extracts show inhibitory activity against FCoV and SARS-CoV-2. However, it remains unclear whether peak plasma concentrations in humans can reach levels needed to inhibit viral infection following consumption of teas or Covid-Organics. Clinical studies are required to evaluate the utility of these drinks for COVID-19 prevention or treatment of patients.

Artemisia annua L. hot-water extracts show potent activity in vitro against Covid-19 variants including delta

“…The lowest ART content (BUR) yielded the greatest potency (the lower the IC 50 , the more potent the drug/extract), providing evidence that ART is not the only active antiviral agent in these extracts. Nie et al (2021) further validated that ART was not the only anti-SARS-CoV-2 compound in the extracts by showing that aqueous extracts of the PAR cultivar of Artemisia afra , an Artemisia species lacking ART, had an IC 50 of 4.1 mg/mL, within the range of 3.1–13.0 mg dried extract/mL of the A. annua cultivars studied therein. As already reported for extracts used in this study, no cytotoxicity was observed at a dry weight of ≤50 μg in the extract of any cultivar ( Nair et al, 2021 ).…”

“…Others also observed that compared to A. annua L., A. afra Jacq. ex Willd., a related perennial species lacking ART, was equally effective against SARS-CoV-2 with IC 50 values of 0.9–3.4 and 0.65 mg/mL extract, respectively ( Nie et al, 2021 ). Although those results indicated that both A. annua and A. afra have potent anti-SARS-CoV-2 activity in vitro and that the effect was not ART-dependent, it was unclear whether A. annua is effective against emerging variants.…”

Promising Antiviral Activity of Agrimonia pilosa Phytochemicals against Severe Acute Respiratory Syndrome Coronavirus 2 Supported with In Vivo Mice Study

“…However, effective antivirals are still needed for patients who are not vaccinated yet or when the vaccines fail to work efficiently. Treatment of COVID-19, unfortunately, remains largely supportive [27]. Many researchers have conducted studies on the antiviral activity of the currently utilized drugs for different diseases which are called drug repurposing.…”

Synthesis and in vitro Study of Artemisinin/Synthetic Peroxide‐Based Hybrid Compounds against SARS‐CoV‐2 and Cancer

“…[8] Recently, it has also been shown that plant extracts from Artemisia annua, which contain artemisinin, exhibit antiviral activity against SARS-CoV-2 in vitro. [9] These findings back the hypothesis, that African countries have been hit later and weaker by the pandemic than expected, due to widespread use of artemisinin based traditional antimalarial medicine or artemisinin-based combination therapy (ACT). [10] The anti-SARS-CoV-2 potential of artemisinins (Figure 1A) was also determined in a pharmacokinetic model in vitro.…”