Tea with Sage, perilla herbs Repress SARS-CoV-2 replication
Posted On December 11, 2020
The current situation of the SARS-CoV-2 or COVID-19 pandemic shows an unparalleled socioeconomic and medical crisis. There are highly efficient treatment options preventing mortality and morbidity that are not largely accessible and approved drugs are barely affordable in developing countries.
To spot cost-effective and universally available options, the researchers from the University of Duisburg-Essen, Germany, tested common dried herbs that are consumed globally as herbal teas.
Herbal teas are made from perilla and sage herbs from the mint family have revealed to hold back the SARS-CoV-2 replication in a laboratory study.
As per the study, aqueous infusions made by boiling leaves of the Lamiaceae plants, sage and perilla, extend strong antiviral activity against SARS-CoV-2 in human cells.
Both sage and perilla belong to the family of Lamiaceae which includes other significant aromatic spices such as mint, basil, marjoram, rosemary, lavender, oregano, and thyme.
Sustained antiviral activity was obvious even when cells were treated for only half an hour and in therapeutic and prophylactic regimens. The low cost and high availability of substances might give help during the pandemic, particularly in low-income regions.
Usage of non-pharmaceutical interventions important
The study conducted by seven researchers, also noted that even after vaccine approvals it will take several months until the convalescent and vaccinated individuals set up herd immunity. Non-pharmaceutical intervention and antiviral treatments are, thus, significant to restrain the death rate due to Covid-19.
However, they also said herbal teas consumptions cannot and should not restore clinically-approved drugs and non-pharmaceutical interventions.
The low-cost and universal availability of herbal teas may relieve or prevent some of the suffering prompts by the pandemic.
In the age of modern medicine, some people have reservations relating to traditional and herbal medicine usage. However, a highly pertinent fraction of newly approved modern therapeutics indirectly or directly initiate from natural products.
How the study was conducted
The researchers used an experimental setup for the short-term incubation of infected cells with herbal teas. For one hour the scientist infected highly SARS-CoV-2-permissive Vero E6 cells before removing the virus suspension. Then different dilutions of aqueous infusions of perilla and sage were added.
Aqueous infusions are then applied that were prepared by boiling up the coriander, perilla, and sage leaves and following simmering at 60°C for 2 hours to make sure complete extraction of the water-soluble components of the herbs.
Interestingly, the short-range treatment with perilla and sage infusions was adequate to drastically inhibit the replication of SARS-CoV-2.
To further validate the impact of herbal teas on SARS-CoV-2 replication, the researchers said they repeated the experiment with two different doses of the virus and stained infected cells for immunofluorescence microscopy. The number of infected cells clearly decreased after treatment with infusions of perilla and sage.
The researchers also used dried herbal material along with fresh ones. The study noted that herbal teas prepared from commercially available tea bags or dried herb leaves may also contain sufficient concentration of the antiviral compounds.
Dried sage leaves retained most of the antiviral component whereas dried perilla was less effective as compared to fresh perilla leaves although significant inhibition of viral replication was observed.
The growing research activities in exploring application area of dried herd in treating serious disease and infection is expected to create lot of opportunity for the dried herbs market key players across the globe.