Research over the past two decades shows that certain plant and algae compounds may be able to fight the new COVID-19 coronavirus. Let’s review the evidence showing how some plant medicines inhibit similar coronavirus infections such as SARS, MERS and Ebola, and why this may also apply to the SARS-CoV-2 coronavirus.
(Note: The research illustrated in this article is not to be considered a substitute for medical treatments or vaccination against COVID-19. See your doctor if you have symptoms or tested positive for COVID-19.)
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What is COVID-19?
The virus was initially named novel coronavirus of 2019 (nCoV-2019 or 2019-nCoV) as of now. This has now been renamed as SARS-CoV-2.
The condition that is caused by SARS-CoV-2 is now called COVID-19.
Sequencing of the virus has determined it to be 75 to 80 percent match to SARS-CoV (the first one) and more than 85 percent similar to multiple coronaviruses found in bats.
Investigators suspect that the virus originated at the Huanan Seafood Wholesale Market. The market’s vendors have been selling live or butchered animals in addition to fish and other marine life.
SARS stands for severe acute respiratory syndrome. It is a coronavirus or CoV. Coronaviruses also include cold viruses and influenza viruses. They are called “corona” viruses because they have spikes on their surface. These spikes are one of the reason colds and flu coronaviruses (and SARS-CoV-2) are so infective.
Researchers from the Wuhan Institute of Virology published a paper on January 23, 2020. Their paper informs that COVID-19 has a 96 percent genome match with a bat coronavirus.
They also stated that COVID-19 utilizes the same cell entry receptor as the SARS-CoV of 2002-2004. The receptor is ACE2. We’ll discuss the importance of this later.
It has yet been determined whether the infection is as lethal as SARS. SARS is another outbreak that began in China in 2002, infecting people through 2004. More than 700 people died worldwide of SARS.
A study published on January 24 from the University of Hong Kong-Shenzhen Hospital in Shenzhen studied six patients of COVID-19. They also determined that the virus was most similar to a SARS coronavirus found in Chinese horseshoe bats.
Red algae for SARS and MERS coronavirus
A few years ago we published research showing that an extract from red algae – called Griffithsin – can fight SARS and MERS coronavirus infections. Red algae Griffithsin has also proven to be antiviral against HIV-1 (human immunodeficiency virus), HSV-2 (Herpes simplex virus), HCV (Hepatitis C) and the Ebola coronavirus.
What do these viruses have in common? Along with COVID-19, they all have glycoprotein shells around them. According to doctors at the University of California at Davis:
“Griffithsin is a marine algal lectin that exhibits broad-spectrum antiviral activity by binding oligomannose glycans on viral envelope glycoproteins.”
The researchers are discussing what is also called a mannose-binding lectin. Mannose-binding lectins have been shown to penetrate and break down the shells that surround this class of viruses – which includes COVID-19 virus.
The red algae extract above was found in the Griffithsia species of red algae. This is not the only species of red algae that contains mannose-binding lectins.
Another mannose-binding lectin found to be antiviral against these viruses is the Scytonema varium red algae, also called Scytovirin. Another one was found in the Nostoc ellipsosporum algae species – called Cyanovirin-N.
A 2019 study from France’s Institut de Recherche et Développement tested a number of other species, and found the Ulva pertusa algae species contained lectins that fight these coronaviruses. They also found the Oscillatoria agardhii blue-green algae halt the replication of these viruses.
A 2016 study from the University of Louisville School of Medicine also studied Griffithsin and found it also inhibited SARS-CoV as well as HIV and similar viruses. The researchers wrote:
“These findings support further evaluation of GRFT [Griffithsin] for pre-exposure prophylaxis against emerging epidemics for which specific therapeutics are not available, including systemic and enteric infections caused by susceptible enveloped viruses.”
Studies have found that these mannose-binding lectins break down the glycoprotein shells of the viruses mentioned above, including Ebola and SARS. A number of animal tests and human cell laboratory tests have shown that these mannose-binding lectins are successful in halting replication of the coronavirus.
In a study on mice with Ebola, researchers found that Griffithsin halted not only replication, but made mice immune to the virus. Similar results were found with SARS and MERS infections.
A 2018 study from New York’s Center for Biomedical Research tested the effectiveness of Griffithsin against enveloped viruses. The researchers found that Griffithsin extracts from red algae inhibited HIV infections, HPV (human papillomavirus) and herpes simplex-2 viruses. The researchers also found that Griffithsin protected monkeys from HIV and mice from being infected with HSV-2.
This means that Griffithsin – from red algae – could make an effective vaccine of sorts. Are researchers testing this against COVID-19?
It is currently unknown what scientists are studying. But often the commercial focus is upon compounds that can be patented.
In the 2018 study from the University of California mentioned above, the researchers reviewed the technical ability to mass-produce Griffithsin, in this case, for HIV infections, using plants to produce the extract. They illustrated the end cost to be quite low:
“In this study, we conducted a techno-economic analysis (TEA) of plant-produced Griffithsin manufactured at commercial launch volumes for use in HIV microbicides. Data derived from multiple non-sequential manufacturing batches conducted at pilot scale and existing facility designs were used to build a techno-economic model using SuperPro Designer® modeling software. With an assumed commercial launch volume of 20 kg Griffithsin/year for 6.7 million doses of Griffithsin microbicide at 3 mg/dose, a transient vector expression yield of 0.52 g Griffithsin/kg leaf biomass, recovery efficiency of 70%, and purity of >99%, we calculated a manufacturing cost for the drug substance of $0.32/dose and estimated a bulk product cost of $0.38/dose assuming a 20% net fee for a contract manufacturing organization (CMO).”
This is the nature of treating disease with plant medicines: Plants are economical and productive on a large scale, as we know from food and herbal medicine production. (See last section below about commercial availability.)
What are mannose-binding Lectins?
The central qualifying characteristic of red algae according to the research summarized above is that they contain mannose-binding lectins. Griffithsin, for example, is a mannose-binding lectin.
Well, many other plants contain mannose-binding lectins according to scientific research.
We have published other research evidence showing that mannose-binding lectins from other plants can also fight SARS-related viruses. A number of studies have shown that plants that contain mannose-binding lectins can significantly stimulate the immune system and help prevent a number of infections.
A 2007 study from Belgium’s University of Gent tested plant-derived mannose-binding lectins on SARS (severe acute respiratory syndrome) coronavirus and the feline infectious peritonitis virus (FIPV).
The researchers studied known plant lectins from 33 different plants in the laboratory, using infected cells. The researchers wrote:
“A unique collection of 33 plant lectins with different specificities were evaluated. The plant lectins possessed marked antiviral properties against both coronaviruses with EC(50) values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC(50)) at 50-100 micrograms per ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding lectins.”
Of the 33 plants tested, 15 extracts inhibited the replication of both coronaviruses. Those antiviral lectins were successful in inhibiting the replication of the viruses.
The 15 coronavirus-inhibiting plants were:
• Amaryllis (Hippeastrum hybrid)
• Snowdrop (Galanthus nivalis)
• Daffodil (Narcissus pseudonarcissus)
• Red spider lily (Lycoris radiate)
• Leek (Allium porrum)
• Ramsons (Allium ursinum)
• Taro (Colocasia esculenta)
• Cymbidium orchid (Cymbidium hybrid)
• Twayblade (Listera ovata)
• Broad-leaved helleborine (Epipactis helleborine)
• Tulip (Tulipa hybrid)
• Black mulberry tree (Morus Nigra)
• Stinging nettles (Urtica dioica)
• Tobacco plant (Nicotiana tabacum)
With regard to the last plant mentioned, much of the research now in development for large scale production of Griffithsin is focused on utilizing tobacco plants. This is because tobacco is easily produced in grow operations. But it should be noted – contrary to some information found online – that the tobacco plant does not naturally contain Griffithsin. Researchers have genetically implanted the Griffithsin gene into some tobacco plants in order to possibly mass-produce the antiviral compound from these genetically modified tobacco plants.
But as we see from above, tobacco, along with taro, nettles, and leeks, is also antiviral against coronaviruses. This doesn’t necessarily mean that smoking tobacco will convey its antivirul properties, however.
Note about commercial availability of red algae
As mentioned in another article, Griffithsin extract is currently being pursued by commercial interests looking for a long term patent with a pharmaceutical model. Thus, this product is not available commercially at this time.
Red algae is a supplement that can be purchased in health food stores and online. Most of the commercial supplements labeled red algae utilize the Gigartina species of red algae (such as Gigartina skottsbergii). This species has been tested against HSV and HIV in laboratory testing, but not on CoVs to date.
These studies indicate that the ability to break down the glycoprotein shell of these enveloped viruses is also a feature of the Gigartina red algae.
Talk to your doctor if you or a family member has symptoms of COVID-19.
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