Anti-Viral Plants

Three recent studies reviewed the anti-viral activity of Japanese wasabi, the Chinese herb Elsholtzia rugulosa and the fruit Chaenomeles sinensis.

Influenza, commonly referred to as the flu, is a contagious infection of the respiratory system that is caused by influenza viruses, including types A, B and C.

Flu viruses are transmitted through the air in tiny droplets when an infected person coughs, sneezes or talks. Individuals are then exposed to the virus through inhalation or by contact with objects such as telephones, door handles, railings or computer keyboards. The virus may cause infection when it enters the eyes, nose or mouth.

In general, the flu is more debilitating than the common cold. Symptoms such as fever, body ache, extreme fatigue (tiredness) and dry cough are often more severe in flu than in the common cold.

A study conducted by researchers in Japan examined wasabi (Wasabia japonica), which has traditionally been used as a spice in Japanese foods for its pungent taste and flavor.

The wasabi roots (or rhizomes) and its winter leaves are used as a spice and for processed foods such as pickled wasabi. Because the summer leaves are much larger than winter leaves, the researchers investigated the summer leaves, which would otherwise be discarded.

Previous studies have shown the antiviral activity of the winter leaves. The researchers found that the extracts of summer leaves exhibited the same anti-influenza virus activity as winter leaves and showed a stronger activity than stems, roots and rhizomes.

The study authors concluded that a potent anti-influenza virus activity was discovered in summer leaves of Japanese wasabi; the extracts inhibited influenza virus replication regardless of the hemagglutinin antigen type. Hemagglutinin or haemagglutinin is a protein found on the surface of the influenza viruses responsible for binding the virus to the cell that is being infected.

In a related study, researchers from China examined Elsholtzia rugulosa, a common Chinese herb widely used in the treatment of cold and fever.

They found five active constituents, all flavonoids, possessed anti-influenza virus activity. The flavonoids apigenin and luteolin exhibited the highest activities against the influenza virus.

Finally, another Japanese study evaluated the anti-influenza virus activity of 50 percent ethanol extract of the fruit of Chaenomeles sinensis K(OEHNE), which is widely used as a traditional Chinese medicine to treat throat diseases.

Type A and B influenza viruses were exposed to the extract at various concentrations for one hour at room temperature; then the plaque titers of the treated viruses were determined.

The study found that treatment with the extract at concentrations greater than 5 milligrams/milliliter reduced the plaque titers of both viruses to less than 10 percent compared with untreated viruses. The treatment inhibited viral activity as well.

The authors concluded that high molecular weight polyphenols in the fruits of C. sinensis may neutralize the influenza virus.

Every year in the United States, on average 5-20 percent of the population gets the flu and more than 200,000 people are hospitalized from flu complications, such as dehydration, high fever and extreme fatigue. About 36,000 people die from flu every year.

Some patients, such as older people, young children and people with certain health conditions that lower immunity, including cancer, human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS), are at high risk for serious flu complications.

Children are two to three times more likely than adults to get sick with the flu. Children may also frequently spread the virus to others due to bad hygiene, such as sneezing without covering the nose and mouth.

Treatment for the flu includes bed rest and plenty of fluids, along with symptomatic treatment such as drugs to fight viral infections, reduce fever and help with sore throat and cough. Annual flu vaccinations may help reduce the risks of flu infection. For more information, please visit Natural Standard’s Medical Conditions database.

Comments

[Rufus]

The antiviral properties of various alternative therapies are indeed interesting. I wonder if these therapies need to be consumed long term in order to have an effect. I would also be curious as to whether the use of these herbs in immunocompromised individuals, who may be more susceptible to getting the flu, carries any risk. For example, wasabi is associated with several potential interactions with drugs and other herbs. It may increase the bleeding risk, inhibit COX-1 enzyme activity, affect bone metabolism and interact with agents broken down by the liver. As with all natural therapies, caution is warranted, especially in higher-risk populations.

[DT]

What is the duration of the treatment? How does this herb work? Maybe this herb can relieve flu symptoms, but I don’t know about influenza viruses (types A, B and C).

[molly]

I have found something a little off the topic. Wasabi, which we usually eat along with sushi here in America, is not entirely derived from Washabia japonica. Since the real ingredient is relatively expensive, what is supposed to be American wasabi is a combination of horseradish, mustard seed and green food coloring. You can read more at this link http://www.nutraingredients-usa.com/news/ng.asp?id=73408-biocell-technology-wasabia-japonica-i-sabi

[ATAD]

I was reading a Newsweek article, and apparently, wasabi is now a topping for hot dogs, popcorn and salad at a California-based company, Wasabi Watusi. This company is also planning on formulating wasabi-flavored cheese! The company was actually named after the facial contortion your nose makes after tasting this potent Japanese plant.

[S. Kalish]

Molly, even horseradish may have some medicinal properties. So maybe the fake wasabi can be therapeutic, if not as an anti-viral, then as something else. I’m always skeptical about anti-viral claims, and nothing in these articles changed my mind — way too preliminary at this point.

[Dr Brian Oates]

To read more about the health benefits of real wasabi (Wasabia japonica), please go to www.wasabia.com

[lana]

Excitingly, wasabi has not only anti-viral properties, but it also helps prevent tumor metastases. A study claimed that 6-(methylsulfinyl)hexyl isothiocyanate (6-MITC), a constituent from wasabi root, appeared to reduce metastasized lung foci in pulmonary melanoma cells of B16-BL6 mouse (http://www.ncbi.nlm.nih.gov/pubmed/16647224?ordinalpos=5&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum). Moreover, none of the tested objects showed signs of toxicity from 6 MITC.

[DNT]

Now a days, people are researching everything. Viral infection sometimes is very difficult to treat. Soon or later, all of the antibiotics will not able to kill those viruses due to resistances. Researchers are working very hard to find better antibiotics and treatments, especially for HIV infection.

[ley]

Not only is wasabi known to have anti-carcinogenic, anti-inflammatory and blood-thinning properties, but it also possesses anti-microbial characteristics. As a result of this newfound anti-microbial property, research was conducted in Japan. Nonetheless, after confirmation of this characteristic, it was actually added to some formulations of Japanese toothpaste to prevent tooth decay!

[Darcy]

It would be helpful to know if there are any downsides to these anti-viral plants. Do they fall into that category of herbs that have been used to treat illnesses in times before modern medicine? Would a visit to the "wise" woman or man in earlier eras have resulted in treatments with these Japanese and Chinese plants? What is the history of their use in healing the sick? It would be interesting to note these facts and if that information is what spearheaded the current scientific trials.

[Eva]

When I read about studies of long-existing plants providing significant healing properties, I wonder if we are going to be forever re-inventing the wheel. It is my understanding that indigenous healers throughout the ages have discovered (probably through trial and error, although regrettably using real humans as test subjects) the value and properties of hundreds, maybe even thousands of plants, that populate the various regions of the world. In our current era, so many of these findings are either ignored or rediscovered. I don’t know the history of the particular plants of this study, but I can easily imagine that this is not the first time that "medicine men" have learned of their healing ability.

What troubles me is that so many of these "talented" plants are not being protected and groomed to benefit the whole of society. Does it seem exaggerated to say that modern medicine is still catching up to ancient medical knowledge of nature’s bounty? Instead of looking to create some synthetic healing capability, why aren't we treasuring and exploring the possibilities of what we are already blessed with?

[AJ]

Chemicals that are found in wasabi have been portrayed to possess antifungal, antibacterial and antiviral properties. They may also retard platelet aggregation and protect against cancer. This agent has also been observed for its anticoagulant effects. For instance, it was illustrated that the essential oils prepared from the leaves, rhizomes, petioles and roots of the wasabi plant inhibit platelet aggregation. The study revealed that the effects were immediate, whereas aspirin would need 30 minutes to produce an effect. Alternatively, the potency of wasabi was only 1/10th of aspirin, but further research is being conducted.

[lilly]

There are few plants out there that have antiviral properties. For example, extracts of Hypericum perforatum (St. John’s wort) have antiviral effects against HIV, hepatitis and other diseases. However, its use is limited due to the interactions with other drugs and herbs/supplements. (http://www.intmedpress.com/Journal%20Management/display.cfm?viewinfo=3F74516309504A2F1B441B00401A641526542A285845171F074401400D31545E1A0C11464F275232551A155E1602110648545E07104209330C52)

[xuan-ngoc]

It might be a little off the topic, but I came across this article and found it quite interesting. The Chinese herb Elsholtzia rugulosa has been recently discovered to have two more glycosides, maltol 6'-O-beta-D-apiofuranosyl-beta-D-glucopyranoside and maltol 6'-O-(5-O-p-coumaroyl)-beta-D-apiofuranosyl-beta-D-glucopyranoside (http://www.ncbi.nlm.nih.gov/pubmed/18404347?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum). I wonder if these two have any contributions to its antiviral effect.

[Daddydoctor]

Something worth mentioning is that it looks like Buckwheat honey is the only honey that has been well studied for children’s could and cough. There are some good reasons why researchers are using buckwheat honey: It is darker and has more antioxidant properties (from phenolics, peptides, organic acids, enzymes, Maillard reaction products and possibly other minor components) than other honeys. There is a Web site that does a good job of bringing together the scientific research on this. There it has a lot of links directly referencing well-respected scientific articles. Check out http://www.honeydontcough.com

-Daddydoctor